More Than Meets The EyeThe Stories Behind the Development of Plastic Lenses

About the Author

Joseph L. Bruneni is the author of "LOOKINGBACK, an illustrated history of the AmericanOphthalmic Indusl1}', II a hard cover book pub­lished in 1994 and still in print. He is a frequentcontributor to most of the major optical tradepublications and writes regularly-appearingcolunUls in a number of them. He serves as aspecial consultant to the Optical LaboratoriesAssociation (OLA) and is a member of the OcularHeritage Society. He currently serves as an assis­tant professor teaching ophthalmic optics at theSouthern California College of Optometry.

On the Cover

The cover illustrates key elements in thedevelopment of ophthalmic lenses.Upper rigbt: Tltis is the first known painting toshow someone wearing eyeglasses. It was paintedin the year 1252.Directly below: Pince-nez glasses were in voguearound the turn of the century. They often featureda chain or ribbon to catch them when they fell offthe nose.At left: Frank Strain was one of the two inventivechemists at PPG who developed and patented allyldiglycol carbonate (CR-39® monomer) in 1940.Due to the war, ule patent was not issued until 1945.Center: Amodel of the atomic structure ofCR-39 monomer.Bottom left: Tltis energy-efficient landmark glasstower in Pittsburgh, Pa., serves as internationalheadquarters for PPG Industries, a global manufac­turer of coatings, glass, fiber glass, and industrialand specialty chemicals.

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(Ue Beginning

By the time World War II began, the

plastics revolution was already well underway.Polystyrene resins had been producedconunercially since 1937 and nylon, the firsthigh-performance engineering plastic, was alsoa product of the 1930s. As the war began, boththe Allies and the Axis powers faced severshortages of natural raw materials. The plasticsindustly turned out to be a rich source ofacceptable substitutes. Realization of this factled to concentrated efforts by the industly todevelop other new plastics.

With tlus heightened interest in plastics,PPG Industries-known as Pittsburgh Plate

Glass Co. until 1965-began searching for away to create an allyl resin with low-pressurethermosetting properties. Rohm & Haas hadah'eady developed Plexiglas® resin and DuPont

chenusts had invented Lucite® resin, both ofthem thermoplastic materials. Pittsburgh PlateGlass Co. owned a subsidialy company inBarberton, Ohio, called Columbia SouthernChenucal Company where a research team was

assigned responsibility for investigating clearresins. The term' Columbia Resins" was

chosen to serve as the name of tms proje t.

As a cowpound was isolated and worked onby the team, it was identified by a codenumber. By May 1940, one of the compoundsshowed real pronuse. TIus particular resin wasan allyl diglycol carbonate (ADC) monomer

that Pittsourgh Plate Glass Co. trademarked

under the rna erial s batch name "CR-39.' In

future year , more than 180 differentcompounds of this clear resin wereindividually researched and investigated.

THE 39TH COMPOUND

The 39th attempt was the most promisingbecause it offered some unique characteristics.Among them was the fact that the resin couldbe combined with multiple layers of cloth,paper and other materials to produceexceptionally strong laminated productscapable of being molded into a variety of

reinforced shapes. Tlus discovelY marked thebeginning of what woul come to be majo~:,)

new induStly called "reinforced plastics."L..

"'0

The first conunercial use for PittsburghPlate Glass Co.'s new monomer iJwolvedcombining the resiJ1 with fiberglass (anotherPitts urgh Plate Glass Co. product) to form a)]

molded fuel tank for the B-17 bomber, the ( )famous Army Air Force plane that saw service

in evelY theater of operation during World WarII. The fuel tanks were molded of materialslan1inated with CR-39® resin and lined \\ith aspecial rubber compound that became self­sealing when the tank was pierced by bulletsor shell fragments. ReplaciJ1g conventional fueltanks with tanks lanunated USiJ1g CR-39 resinmade it possible to greatly reduce the plane'sweight, extending the bomber's range andcontributing substantially to the war effort.

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!...,I UNITED STATES PATENT OFFICE

2,370,565

THE SEARCH

FOR PEACETIME USES

Avariety of uldustries were contacted in asearch to find customers for the left-overCR-39® resul. Afew individuals in the

ophthalnuc industry indicated some initialinterest, particularly because of the material'sresistance to ullpact. One company wasinterested enough to set up a special researchdepartment to tty to develop plastic eyeglasslenses. The company was Uluvis LensCompany, at that time located Ul Dayton, Ohio.Univis was a leading lens producer illvestulglarge sums in an attempt to produce plasticlenses from CR-39 resin. Their efforts areexplained in greater detail Ul Robert Graham'sstOly (see page 14). Eventually Uluvis

abandoned the project. It's interesting to notethat, following successful production of

plastic lenses by Armorlite, SOLA and Essilor,Uluvis did eventually become a major plasticlens producer.

~~>< Patented Feb. 27, 1945

~--.;

did know that when it happened, ulstead of anexpensive railroad tank car, they would end up

with a useless steel-encased slab of plastic.

FUEL MONITORS

THE WAR ENDS

Another umovative use for the new CR-39®resul in aircraft was production of transparenttubes that were embedded ill fuelliIles runningthrough the flight enguleers' compartment,providillg the crew a visible gage to uldicate

fuel flow to each engule. These tubes made ofCR-39 resin replaced tubes made of glasswhich were often shattered during combat,spraying gasoliI1e throughout the cockpit.There was also some minor use of transparentCR-39 resm for makiIlg lenses during the warbut the lenses produced were Yz" to %" thickand prunarily used for reflector andsearchlight applications.

When the war ended Ul 1945, allgovernment contracts were cancelled, andPittsburgh Plate Glass Co. 's Barberton plantended up with a railroad tank car full of allyldiglycol carbonate (CR-39® resin), all that

was left from wartune production. The 38,000pounds of resin rema.iIung ill the tank carrepresented a costly mvestment for thecompany, so a search was launched for civilianmarkets that could use this transparent resin.PPG old-wners involved durillg that periodremember how tune-sensitive tius projectbecame. CR-39 reSUl rema.iIls a liquid until acatalyst is added. Eventually, however, thematerial polymerizes, or hardens, without acatalyst. In those early days, no one knew howlong that self-curing process would take. They

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Franklin Strain, standing at the right,wa the co-developer ofallyl diglycolcarbonate (CR-3~ mOnOlllel) alongwith Frank A1Ils/wt. He is seen heredi cussing the ojJticaljJrojJerties of CR­39 monomer with several PPCmarketing e:recutives. l\1uS/wt andStrain's originaljJatent application,dated October 15, 1940, stated,"Thus, we have been able to jJrejJarecomjJlex esters of various polyglycolssuch as diethylene, trieth)'lene,tetraethylene, jJentaet/l)'lene,dijJrojJ)'lene, triprojJylene,tetraprojJ)'lene, dibut)'lene, or otherpolygl) col. ' Who could have jJredicted

"'" how such an exotic chemicalv~

( co nbination would imjJact C)'ewear inth ~)'ears to come?

(. /J~~

,. J. l~fO.

FLAT SHEET MARKET

Until 1960-61, PPG's primaty CR-39® resinsales were for flat sheet applications. Thesesheets of transparent plastic were used forpersonal safety equipment and clothing such

as welding helmets, industrial goggles, gasmasks, etc. Another widespread use of CR-39resin during those post-war years was forwindshields of industrial crane cabs and othervehicles used in industrial plants. Much of theearly work in developing optical lenses wasconcentrated on strong correction lenses,primarily high plus lenses used for post­cataract patients. This was an inlportantsegment of the lens industly in those daysbefore development of the inter-ocular lens.

As the optical industly gradually learned

how to cast lenses from CR-39 resin, and howto edge and surface these new lenses, sales to

the optical industly grew slowly but steadilyuntil 1975, when more than 90 percent ofPPG's CR-39 resin sales were to the opticaltrade. In 1975, PPG's marketing expertspredicted that plastic lenses-at that timerepresenting 15 percent of all eyewear in the

.S.-would grow to 30 percent by 1978. Fewpeople outside of PPG believed that optimisticpredictiol'i. Today, plastic lenses representmore than 80 percent of the .S. market.

THE TANK CAR

Looking back to that tank car of CR-39®monomer sitting forlornly on a siding inBarberton, Ohio in 1946, the PPG employeeswho tried to sell the contents before the resinsolidified uncovered two important facts. Thefirst was that CR-39 monomer was remarkablystable with an amazingly long shelf life. Thesolidifying they feared never came to pass.Their other discovelY was that there wasindeed a viable market for a stable,transparent, inlpact-resistant material forproducing spectacle lenses.

PPG-The Company

The company known today as PPG

Industries, Inc. was founded by two velYdissimilar men. John Pitcairn was aconservative railroad official. In 1880, he

linked up with Captain John B. Ford, aflamboyant entrepreneur. For some reason,now forgotten, these two men came to theconclusion that they could produce andmarket plate glass. This was an ambitiousundertaking because, at that point in time,plate glass for the United States was almostentirely imported from Europe. More than adozen U.S. companies tried to compete in thismarket but all ended as financial failures.Belgium, England, France and Germanymonopolized both the machinely and the skilledtechnicians required to produce plate glass.

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PITTSBURGH PLATE GLASS

COMPANY

With Pitcairn as major stockholder, CaptainFord founded the lew York City Plate GlassCompany in 1880 and began building a plantin Creighton, Pa. It didn't take long for the pairto run out of money. To get needed capital, thecompany was reincorporated in 1883 as thePittsburgh Plate Glass Co. This also marked theyear the company produced their first plate

glass. Success soon followed those early effortsand by 1895, the company moved theircorporate headquarters to Pittsburgh, Pa. Bythis time, the company produced 20 millionsquare feet of plate glass annually.

Ford and his sons had a disagreement withPitcairn in 1896 and sold their interest inPittsburgh Plate Glass Co. They left to foundthe Edward Ford Plate Glass Company inToledo, Ohio. In 1930, tllis company mergedwith the Libbey-Owens Sheet Glass Company,forming the well-known Libbey-Owens-FordGlass Company.

PITCAIRN TAKES OVER

With Ford gone, Pitcairn took over aspresident and, in 1899, established anindependent company called ColumbiaChenlical Company, based in Barberton, Ollio.TIlis new operation was created to assure PPG

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a constant supply of soda ash, a major

component of glass. The Columbia ChenlicalCompany was responsible for inventing

CR-39® resin during World War II.,J.n 1951,Pittsburgh Plate Glass Co. became the soleowner of Southern Alkali and merged it withColumbia, forming the Columbia-Southern

Chemical Corporation. Tllis companyultimately became PPG's chenlical division.

By 1900, Pittsburgh Plate Glass Co. wasselling 13 million square feet of plate glassannually. The company had become thecountty's most successful producer of plateglass. Imported plate glass dropped to less

than 15 percent of what the nation consumed.That year, PPG bought a majority interest in

Patton Paint Company which became PPG'scoatings & resins division. In 1902, thecompany reversed tradition and expandedoperations to Europe by buying a glass factoryin Courcelles, right in the heart of the Belgianglass industty

PPC fOllnderJolm Pitcairn

PPC founder CaptainJohn B. Ford

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TODAY

PPG Industries, Inc. is a diversified globalmanufacturer and a leading supplier ofproducts for manufacturing, construction,automotive, chemical processing andnumerous other world industries. The

company produces protective and decorativecoatings, flat and fabricated glass products,continuous-strand fiber glass, and industrialand specialty chemicals. They operate 70major manufacturing facilities in Australia,Canada, China, England, France, Germany,Ireland, Italy, Mexico, the etherlands,Portugal, Spain, Taiwan and the United States.The company conducts research anddevelopment at eight facilities worldwide.

The Evolu~ion ofOph~halrnicLenses

The word "lens" comes from the Latin word"lentil," a species of bean that rather vaguelyresembles the shape of a lens. Single pieces ofconvex-shaped glass or rock crystal have beenfound in ruins dating back thousands of years.These primitive lenses were used as magnifiersbut it wasn't until the 13th century that anyonethought of combining them into spectacles.

READING STONES

The first mention of magnifying lenses isfound in a famous treatise on optics written byArab physicist, al-Hazen (996-1038). AI-Hazenobserved that a segment of a glass sphere, ineffect a plano-convex lens, would magnifyinlages. Later, Italians would call magnifyinglenses lapides ad legendum which translates to"stones for reading," most likely because theywere made from rock crystal rather than glass.

The very earliest spectacle lenses weremade of quartz crystal and were given thename "pebble lenses" in the optical trade.Other early lenses were created from hand­

blown glass. As the optical industry grew,hand-blown glass was gradually replaced bymore easily-formed lens blanks made from flatsheets of glass. These were called' dropped"lenses because of the process in which flatsheets of glass were heated until they softenedenough to drop into cavities that shaped theblanks to a rough curve.

The earliest origin of eyeglasses is a matterof some dispute. In his famous "Opus majus,"Roger Bacon described how a convex lensmagnified and offered a suggestion that such alens might help those with vision problems.\Vhile Bacon did not invent glasses, it is stronglybelieved that their first use undoubtedly startedduring his time (I214-1294).

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::Dit g~tufi \lonltllcr olltr 5)or111~rtl>n llit glMtr '))0 lim nnlllvorttl~atlurc~ mil" frcf}t/gar ~dll1t1ll rcf2<lrffl~it fInD /§r ~it I wrr tltr btl>ilrff.

This Middle AgesWOOdCllt shows acllstomer trying one)'eglasse from astreet merchant.WOOdCllt, Werke G.Rodenstoch,~IIllnchen.

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EARLY LENSES

Contemporaly writers tell us that the RomanEmperor ero viewed sporting events in hiscoliseum through an emerald lens. Theemerald was probably chosen because of itspleasing green color. Tllis was undoubtedly theworld's first tinted sun lens. It's also believedthat the stone cutter accidentally produced aslight concave shape to the stone wllich mayhave helped a near-sighted ero see better.

CRYSTAL LENSES

The earliest spectacles were produced byglaziers in Venice, Italy. Lenses in these firsteyeglasses were made from quartz or rockClystal and produced by gold craftsmenexperienced in working with rock Clystal whenproducing jewelty. Artisans at that time wereclosely governed by individual statutes thatapplied to evelyone engaged in a specific craft.The Cristallieri, as these craftsmen came to becalled, received their own code in the fall ofthe year 1284. Tllis seems to indicate thatspectacles must have been common by tIlisperiod if they required their own regulations.

One of the regulations governing spectaclemakers involved substituting rock Clystallenses with inferior glass lenses. Tllis wasstrictly forbidden. Rock Clystal was velYexpensive wIllie glass was considered a lessdesirable material for lenses. Early artisanswere pernlitted to make lenses out of glass butonly if they promised they wouldn't clain1 them

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to be quartz. On]une 5, 1301, the city ofVenice changed the rules and pernlittedpersons to make reading spectacles fromglass, providing they first took an oaU1 in frontof judges that they would never represent thelenses to be rock Clystal.

Bishop Ugone da Provenza, shown in this 13th centu1)!jJainting is the first historical figuTe known to wear glasses.The jJainting can still be seen in the chw'ch oj St. Nicolo inTreviso near Venice. His glasses aTe simjJle magnifiers withshort handles, riveted together so they could jJerch on his nose.Painting copy, Werke G. Rodenstock, Nlunchen.

THE FIRST EVIDENCE

OF EYEGLASSES

The earliest historical figure documentedwho wore glasses was Bishop Ugone daProvenza. This Dominican priest was portrayedin a painting by Tomaso da Modena in the year1252. The painting can still be seen in thechurch of St. Nicolo in Treviso, a city nearVenice. His glasses were really nothing morethan simple magnifying lenses with shorthandles, riveted together so they could perchon his nose (see illustration).

GLASSES AND

THE PRINTING PRESS

Spectacles did not come into conunon useuntil some time after Guttenberg invented the

printing press during the mid-1500s. Thatevent marked the real begiIming of the need to

correct vision with eyeglasses. Lenses usedduring that period were biconvex in form andused primarily to correct presbyopia. Sometime later, it was found that biconcave lenseswould help nearsighted persons see moreclearly in the distance. It wasn't until 1500 thatlenses were graded by their focal power. Thiswas the idea of a man named ]ohaImes Kepler.Prior to Kepler, lens powers were defil\ed bythe age of the person wearing them.

By the time the 19th century began, mostglasses were sold in hardware stores:Gradually, gold and silver were used is frame

materials, aIld jewelers bec e logicalsuccessors to hardware mercH . er allselling glasses purchased them as r ad -madeglasses, usually one dozen to the box, aIld soldthem under an "inch-number" system. Awayfrom large cities, itinerant eyeglass peddlerswere the primary method of eyeglassdistribution. Most of their wares wereproduced by EuropeaIl sources. People whothought they needed glasses would tryonready-made glasses, one after another, untilthey found a pair that helped. The lenses inthese factOly-made glasses were always the

SaIne power for each eye.

LENSES

Bausch & Lomb aIld American Optical werethe first AmericaIl compaIlies to iIlitiate massproduction of glass spectacle lenses. Prior to

that time, most lenses were imported fromEurope, either as rough blanks or in uncutform. No optical glass was maIlUfactured in theUllited States until World War I cut offtraditional import glass sources for tIlis countly.

PEBBLE LENSES

Lenses made of rock crystal were origillallyintroduced in England under the name ofScotch Pebble and later as Brazilian Pebble,naInes indicating their country of origin.Crystals are found all over the world, but thoselarge enough to make into eyeglass lenses are

During the eighteenthcentury when wigswere cOJJwwnly wornby IJerso17s ojsubstance, eyegLassFames Jea tured specialsl)[lhlLa tYIJe tempLesthat wOllldJit underthe wig, as seen here.During this period,many len es were madeojnattlral roc/( cI)lstal(jJebble). The stoneswere only Jound insmall sizes andolJticians ofteninserted the Lenses i17circuLar shells made ojleat/leI; hom or woodso theFames could beLa 'gel; as seen here.

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only found in a few countries. During theperiod when pebble lenses were popular,spectacle lenses were about the size of a halfdollar coin. The best crystals were found inBrazil, and interestingly, no rock crystals inpaying quantities were ever found in the UnitedStates. Pebble lenses normally costconsiderably more than glass lenses. Theywere much harder than glass and, as aconsequence, much more difficult to grind andpolish. Their harder surface made them lastlonger without accumulating scratches. Tllis

was highly valued by consumers.

Even when glass lenses becanle plentiful,

pebble lenses continued to be sold as superiorlenses because of their longer wearingqualities. It wasn't uncommon for eyeglasses to

be passed on from one generation to another.The cost for pebble lenses kept rising as thesupply of rock crystal dinlinished, but theywere still being sold well into the 1920s.

FLAT LENSES

Early lenses, whether made of pebble orglass, were all made in flat form, or biconvexfor plus powerslbiconcave for minus. Flatlenses were easier to manufacture, and no onethought to mal<e dIem any other way. Flat lenseswere still widely used into the 20th century.

The next evolution in lens form came aboutwhen lens designers tried to elinlinate visualproblems created with flat optics use. Lens

makers found dlat lenses ground with aconcave curve on the back side and convex onthe front surface were positioned further fromthe eye and, as a consequence, would provide.,a considerably wider field of view. Tills had the

additional benefit of reducing contact betweenthe lens and the wearer's eyelashes, sometlling

that had always been a problem with flatlenses. Meniscus lenses were described asearly as 1645 but not used for eyeglasses untilthe periscopic lens was introduced in 1804.These lenses had a standard -1.25 back curvefor all powers. Conventional six base melliscuslenses first became available around 1890.

LENS TINTS

Early in the evolution of ophthalnlic lenses,lens producers looked for ways to increaseprofits, for them and for their retailers. Thefirst lens "add-on' was simply adding color toraw glass. Some of the early uses of color inlenses included treatment of disease and evenclaimed improvement of vision. Early in the19th century, blue, pink and green lenses wereintroduced. Later, Dr. William Crookes, anerninent British scientist, developed a specialcolor that filtered infra-red rays and wasnamed "Crookes" after the inventor. This coolblue/gray shade was quite effective butunfortunately gave wearers a rather ghastlylook, with unattractive shadows beneath theeyes. American Optical produced a moreattractive pink shade called "Cruxite." Betweenthe two World Wars, pink lenses became very

popular. Soft-Lite® lenses by Bausch & Lombultimately became the top-selling premiumlens. Later BM developed Ray-Ban® andG-1S® proprietaly sunglass lenses. Ray-Ban is

today on the ten best-known trademal'ksin the world.

listed a +0.50 +0.50 compound correctedcurve uncut lens at $1.80 per pair. The samelens in toric form (non-corrected curve) was

$1.55 a pair. The difference was only 25 cents,but it was more than thirty years before old­fashioned toric lenses were totally eliminated.

This was also a time when labs first startedusing automatic bevel edgers for finishinglenses. One of the major benefits of beveledgers was the ability to apply a special 'hide­a-bevel" to high minus lenses. This is anautomatic way of applying most of the bevel tothe back side of the lens, hiding the lensthickness behind the frame. Plus cylinders,especially in higher cylinders, produced anunattractive bulge in the front rim of theframe, follmving the mds of the cylinder. When

As fused multifocals gradually took over themultifocal mal'ket, replacing old-fashionedone-piece lenses like the ltex, a new problemarose. Fused multifocals were surfaced on theback side which meant labs surfaced themwith the cylinder on the back surface. Singlevision stock lenses at that time were all

produced with plus cylinders on the front side.As patients aged and went from single visionlenses to bifocals, they often experienceddifficulty adjusting to visual differences createdin switching from plus cylinders to minus

cylinders.

The tough job then became convincing

eyecal'e p¥ofessionals to prescribe correctedcurve lenses rather than the less desirabletoric lenses. To provide an idea of thedifference in cost between toric and corrected

curve lenses, American Optical's 1935 prices~

This led to the development of correctedcurve lenses. These modern lenses changed

base curves for evelY one to two diopters ofower. Before long evelY lens

manufacturer was producing standard' aselenses, called ' toric len ong with aseparate line of corrected curve lenses.

Lens designers found that changing a lensdesign from biconvex or biconcave to a 6.00diopter curve provided a wider field of viewfor the wearer. They also found other inherent

optical distortions that cropped up as eyeglasslenses grew larger with increasing frame size.

It was determined that changing front curvesas lens powers changed would minimizemarginal distortions, producing better acuityfor the weal'er.

The use oj colored glass lenses Jor impliedtherapeutic pmjloses or simplyJor the visualcomJort they provided was the firstenhancement Jor ophthalmic len es. One ojthe most exciting asjlects oj lenses made fromCR-Y~ resin was their ability to be tinted toany color oj the rainbow, an imjlossibilit)with glass lenses. Best oj all, the tintingcould be done in a retail oJfice, oJJering newProfit ojlportll nities Jor evel}one.

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cylinders are ground on the back side of thelens, tltis cylinder bulge is completely hiddenby the frame. Tltis provides a considerablecosmetic advantage for minus cylinders, inaddition to their visual advantages.

Minus cylinder lenses were more expensiveto produce than plus, but their advantageswere too obvious to ignore. Lensmanufacturers, facing the heavy costs ofconverting production equipment to minuscylinders decided to convert their lenses tocorrected curve form at the same time. Thisconversion to single vision minus cylinderstock lenses effectively doomed toric lenses, toeveryone's great relief. Today, all single visionlenses are produced in minus cylinder formand are also considered corrected curve.

PLASTIC LENSES

Agreat deal of work was done in Englandbefore and during World War IT in an effort todevelop a lightweight, shatter-proof plasticlens. Most of tltis work resulted from theBritish experience working with acrylic(polymethyl-methacrylate), a material widelyused in Great Britain before and during thewar for aircraft windsltields. IGard, a divisionof Combined Optical Industries, Ltd., aprominent British lens manufacturer, beganproducing prescription lenses made of acrylic.

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These enjoyed modest distribution in theUnited States before World War II. After thewar, McLeod Optical of Providence, R.I., begandistributing inlported acrylic lenses tb otherlabs located in the United States. These IGard®lenses were produced only in finished uncutform and could not be surfaced. They werelightweight but proved to be brittle, subject to

scratching and prone to yellowing after a fewmonths in inventOly.

There were other attempts to utilizeacrylic materials but the plastic lensrevolution was virtually dormant untilPittsburgh Plate Glass Co. came up withCR-39® resin. That event eventually madelightweight plastic lenses a reality.

During the scramble to findjleacetime uses for CR-YfFJresin, some innovative PPCscientists projlosed thatcolorful, long-lastingfishinglures could be made from thematerial. Fortunatel), wiserheads concluded thatojlhl/wlmic lenses offeredgreater opjlortunities.

The Ques~ forPlas~ic Lenses

PART ONE

As the country came out from the depths ofthe depression, popular magazines of the daywere filled with stories of the wonders of newplastic materials that promised to create awhole new world for consumers. Housewives

began discovering the benefits of sturdy,lightweight housewares made from Bakelite®

synthetic resin, the convenience of cellophanefood wrappings and the ease of self-stickScotch® tape. The 1939 World's Fair in ewYork carried the theme "World of Tomorrow,"

and much of the world they predicted involvedthe benefits and glories of plastics.

One familiar plastic developed during thethirties was polymerized methyl methacrylate(PMMA), introduced in 1937 as Lucite® andPlexiglas® resins. This material had excellentoptical properties and was considered suitablefor eyeglass and camera lenses, and forproducing special effects in highway andadvertising illumination. Another plastic waspolytetrafluoroethylene, first made in 1938 andeventually produced conunercially as Teflon®

resin in 1950. Also develop~d during the1930s was the synthesis of nylon.

There were a few far-sighted people in theoptical industry who were convinced that oneof these exciting man-made materials wouldeventually prove to be a suitable material for

ophthalmic lenses. 1\vo basic factors motivatedthis desire for a plastic lens. One was the safetyissue (greater resistance to impact). The otherwas comfort (lighter weight lenses).

SAFETY ISSUES

Auto manufacturers faced a similar safetyissue with automobile windshields. The auto­driving public grew concerned over theserious cuts and injuries that were theinevitable result of broken car windows, oftenin the most minor of traffic accidents. Acleverglass maker found that lan1inating d1in sheetsof plate glass over a strong inner layer ofplastic minimized injuries from broken glass.The first lan1inated automobile windshieldshad an interlayer of cellulose acetate.Pittsburgh Plate Glass Co. produced a superiorwindshield with a polyvinyl butyral interlayerwhich was more yielding, and therefore safer,than cellulose acetate. When laminatedwindshields broke, shards of glass were held

together by the plastic core. Laminated glasswindshields worked so well that someone in

the optical industly decided to adapt a similarlaminated process to ophthalmic lenses.

Called "Motex," these safer laminated lenseswere moderately successful during the thirtiesand forties. They were widely advertised as a"non-shatterable" lens and used mostly forchildren's eyewear. Each pair of lenses camewith a $15,000 insurance policy against eyedamage~ Since there were two layers of glass ineach lens, the layers were kept thin in an effort

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to keep down the weight. Unfortunately, thesethin wafers made the lenses considerably morefragile than conventional lenses, and they oftencracked under normal handling. Theimportant thing, however, was that theirconstruction prevented pieces of glass fromentering the wearer's eyes, making for lessdanger to the wearer.

PLASTIC LENSES

The first serious work in developing anophthalmic lens made from lightweight plasticwas undertaken by an English company,Combined Optical Industries Limited (COIL).COIL developed a plastic lens made from

PMMA in the 1930s. Afew of these early lenseswere distributed in the United States under thename IGard® prior to World War II. Followingthe war, COIL decided there were realopportunities in the States and attempted tomarket their lenses in this country. They met

with little success until 1949 when McleodOptical in Providence, RI., was established asthe exclusive distributor in the U.S. for IGardlenses.

orm Mcleod knew most lab owners in thecountty, so his company enjoyed moderatesuccess in selling IGard lenses to majorindependent labs. It turned out to be a hardsell, primarily because the lenses were so easilyscratched and relatively expensive. Anotherunfortunate attribute of these early lenses was a

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tendency to nu'n a rather ghastly shade ofyellow, even when stored in stock drawers.

During that earlier pre-war perio"- (1938),another company in the United States wasworking on development of a plastic lens.Located in Beverly Hills, Calif., the company

name was "The Unbreakable Lens Company ofAmerica," later shortened to "TULCA." Thecompany was acquired by the Univis Lens

Company and moved to Dayton, Ohio, in hopesthat TULCA's research would give Univis a lead

in development of plastic lenses.

TULCA followed the same path as COIL byutilizing PMMA for their lenses. In ovember1938, M. H. Stanley, president of Univis, sentthree letters to Mcleod Optical, one of the firstAmerican labs to offer plastic lenses to theiraccounts. Mcleod was advised that TULCAlenses were not available for generaldistribution, but Univis was prepared toprovide TULCA lenses for "emergency caseswhere the safety factor predominates." First

division spheres, cylinders and compoundswere priced at $4.00 (with a 15 percentdiscount for Mcleod) with a suggestedminimum retail price to consumers of $10.00to $11.00. TULCA was never able to solve thescratching problem, and Univis ultimatelyclosed the company when they abandonedtheir research and development efforts to

produce plastic lenses.

The famous railroad tanl{carjilled with 38,000jJounds of CR-39J9 monomerthat prompted the search forcivilian 'uses for all)'l digl)'colcarbonate (ADC) can be seenin this 1945 plwtograjJh ofthe shijJjJing ),ard at PPC'sBarberton, Ohio, plant.These marketing efforts led tothe successful develojJment oflightweight jJlasticojJhtlwlmic lenses.

In spite of these disappointments, many in theindustry were fascinated by the crystal clearproperties of PMMA and continued struggling tomake ophthalmic lenses from the material.Ironically, PMMA would later prove to be the idealmaterial to use in fashioning corneal contact lenses(prior to the development of soft contacts).

WORLDWIDE DEVELOPMENT OF

PLASTIC LENSES

Development of what led to today's plastic lenses

came primarily from the efforts of threemanufacturers. The earliest pioneer was RobertGraham, first with the Dnivis Lens Company andlater with ArmorLite, the company he founded inCalifornia. For a period of sLx years, Graham wasthe only source for plastic lenses made of CR-39®resin. Later, SOLA in Australia began experinlentsfor producing plastic lenses, and during that sametime franle, Essilor in France began working toproduce a lightweight organic lens.

The story of how each of these innovativecompanies solved the problems of producing

plastic ophthalmic lenses follows .

•

PART TWO

DR. ROBERT GRAHAM &

ARMORLITE

Graduating from Ohio State University with a

degree in applied optics, Robert Graham tooka position with Bausch & Lomb, at the time,the second largest optical manufacturer in theworld. On learning that nivis was conductingexperinlents to make ophthalmic lenses out of

PMMA, Graham was asked to visit Univis andreport back to B&L on the progress of the

Univis project. Several months following hisUnivis visit, Grallam was contacted by Univis

President Jack Silverman and offered a job inthe sales depat1ment. Largely because of hisstrong interest in the company's experiments in

the field of plastic lenses, Grahanl joined Univis.

UNIVIS LENS COMPANY

nivis was a fast-growing multifocalmanufacturer. Their product line of Flat topmultifocals had become the industry's leading

products and were much favored byindependent laboratories, always in fiercecompetition with the industry giants, Bausch &

Lomb and American Optical. Univis Lensproducts had become the industiy's premiermultifocalline. Grallam was attracted to thecompany because of what he heard about theirinterest in developing plastic lenses. SLx yearsafter joining Univis, he advanced to theposition of company sales manager. Theproject in which he was most interested,

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however, was simply having no success inachieving marketable plastic lenses. By thistime, Univis had spent a third of a milliondollars-a considerable sum for tha~ time­and the company had virnlally nothing to showfor their investment.

TULCA

In their quest for a practical lightweightlens, Univis acquired a company in BeverlyHills, Calif., called TULCA (The UnbreakableLens Company of America). Tllis company hadbeen compression-molding lenses made ofPlexiglas® resin, using metal molds. Univis

purchased TULCA for their technology but sixyears after taking over the company, Ullivisdiscovered they were being sued by CombinedOptical Industries, Ltd. (COlL), the Englishcompany that produced IGard® lenses. COILclaimed to have conceived the TULCAproduction method wllich involved injectionmolding. This process used lligh chrome­

content steel molds, necessalY because of theextreme heat andlligh pressure created duringthe molding process. Highly discouraged bythe whole experience, Ullivis turned their backon the entire plastic lens project.

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Robert Klar/l GrahamJounded theAnllorlite Com/Jan) in Pasadena, Calif.For a period oj six years, he and hiscompany were the world's only sourceJorlenses made ojCR-3~ m01101l1eJ:

E 0 E TO CAL FO

Tlus was a bitter pill for Graham. Hebelieved UIuvis was giving up too easily. Thetecl1Jucians who had been working withGraham on the plastic lens project felt thesame way. When luvis shut down the project,these tecl1Jucians lost their jobs. Bob Lanmanhad been involved with casting lens researchand anti-reflection coating technology at Uluvisand was one of the ones who was let go.Grahanl suggested he and Lanman set up a labof their own to work on the plastic lensproject. Both men moved their fan1ilies fromDayton, Oluo, to Califonua, taking all but oneof the Uluvis lens researchers with them. Theyset up their new company in Pasadena.Graham and Lanman agreed to each draw asalary equivalent to what they had earned at

luvis. Whenever there were no dollars to paythem, they would take the equivalent in shares.Initially the new company was called PlasticLens Company, but the name was later changedto Armorlite.

The terms of their agreement also pernuttedGralulill to fit contact lenses on the side whenthere was no money for salaries. For severalyears, the Graham family was supportedprimarilYl,by contact lens fees (Grallam was aconsultant to Kevin Tuohy, inventor of plasticcorneal lenses) . Grallam's accumulated stockownerslup and Ius cash investment evennlallymade him Armorlite's largest stockholder.

The first plastic lenses produced by theArmorlite Lens Company were made ofpolymethyl-methacrylate (PMMA) , a materialbetter known by the trade names Lucite® andPlexiglas® resins. Injection-molding of PMMAlenses had also been tried but was never

satisfactOlY because of striae introduced duringthe injection process. The required metalmolds were expensive and had a short life.

Graham's team developed a differentprocess wluch involved machining discs madeof PMMA to the approximate desired curves ona lathe. These turned blanks were polished bypressing them between lughly polished glassmolds, using moderate heat and pressure. Tlusminimum-flow process produced a fine­looking lens that was optically clear with nomachining grooves or residue marks.

nfornmately, the lenses enjoyed onlymoderate success. The company had earliertried malting lenses out of styrene butabandoned that material because it was too softand prone to scratclling. The new PMMA lenseshad the sanle problem. Excessive scratcllinghad become the insurmountable problem.

CR-39® RESIN

For some time Dr. Graham had knownabout CR-39® resin, the allyl resin initially

developed by PPG as a bonding solution forwar planes. CR-39 resin had first been usedduring World War II for fuel tanks in bombers.Sheets of tItis new plastic had also beensandwiched between thin pieces of glass andused for bomber windows, strengthening theglass sheets and, in effect, reducing theirweight. Tltis lowering of gross weight extended

the bombers' flight range. CR-39 resin hadbeen classified as a militat)' property duringthe war and, as a consequence, \\ asunavailable to Ultivis. Graham (still at nivis)managed during the war to gain access to fivegallons wltich he used for experimentalpurposes. With the war at an end, andPittsburgh Plate Glass Co. sitting with a

railroad tank car full of the material, word ofits availability reaclIed Pasadena whereGraham jumped at the opportllltity to tl)' itonce again for ophthalmic lenses.

Uke PMMA, CR-39 resin was optically clearbut turned out to be tItirty times moreabrasion-resistant than Plexiglas® or Lucite®

resin. There were, however, certain inherentproblems in casting lenses with CR-39 resin.The first one is easy to understand. The

original design function of CR-39 resin was toact as a bonding agent for gluing togetherlaminated multi-ply materials. This proved tobe a less than desired property for lens

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casting because the resin tended to bond tothe mold, particularly when the mold wasmade of metal. Fortllllately, Graham's groupfavored glass molds.

SHRINKAGE

An equally serious problem was that lensescast from CR-39® monomer experienced a 14percent shrinkage as the material cured. Tltiswasn't a problem when casting plano lenses,since the shrinkage merely made the lensedges retract slightly. When lenses were castwith corrective power, however, a variance intItickness between the center and the edge wascreated. Tltis resulted in a differentialslu'inkage wltich inevitably created opticaldistortions in the finished lens. Grallam's

answer to tltis innate property of CR-39 resinwas to cast tItick blanks in wltich the backcurve matched the finished front curve. Tltisform allowed uniform shrinkage during curingwith no induced distortion. Armorlite wouldthen grind and polish the back surface to therequired curve and tItickness.

Graham would later write about thosetraumatic days. "We will never forget thosenights, month after month, when we sat by theovens listening to the sound of cracking glassmolds!" Breaking of glass molds resulted fromthe combined action of the resin's sluinkingfactor (14 percent) and its adhesive properties(sticking to the mold). Eventllally, after a greatdeal of trial and error, Graham's persistence

J\!Iost of those involved incasting lenses made from

CR-39J9 monomer duringthe first several years werefully convinced that no onewould be able to cast bifocalsin this new lightweightresin. As a result, everyoneconcentrated on singlevision blanh. Here, aflortion of the da) 'sproduction is seen on it'sWO)l to jloc!wging.

A TRIP TO PITTSBURGH

During this period, PPG invited Graham tovisit the Pittsburgh office in appreciation forhelping them find a major peacetinle use forCR-39® resin. Dr. Dial, one of the originalpatent-holders of CR-39 resin, hosted aluncheon at Pittsburgh's Duquesne Club. Therewere many flattering speeches about Graham singenuity, accompanied by awards andsouvenirs. When Graham left the dining roomafter lunch, he found a bright red carpetstretching down the hall and down the steps tothe curb where a long black limousine waited.Dr. Graham tells the story himself in Iusautobiography, "RK.G."

For sLx years, Armorlite had a worldmonopoly on lenses with CR-39 resin. Thisexclusivity e ed when Essilor, then SOLA,followed by American Optical, beganproducing hard re in lenses made of CR-39monomer. Dr. Graham poifits out todaywhen American Optical introduced their ownplastic lenses, Annorlite s business doubled.Plastic l~nses had come of age!

I thought, ow, these PPG men reallyknow how to make a fellow feel ood. I hadn'tgone far on the red et before militaryofficers hustled me off into a side vestibule.

1 adjoining room, a meeting "as being held" 'tfi e1 on ockefeller, vice president of theUnited States. Jus for a little while there, I

enjoyed his red carpet." ~---.::-

paid off when his team found a better glass formaking molds and was able to add a releaseagent to the monomer. Finally, they successfullycasted lenses with CR-39® resin.

The year 1947 saw the Armorlite Companyincorporated and the beginning of lensesproduced with CR-39® resin. For the next sLxears Graham's company was the worldwide

sou ce for hard resin lenses. During thisp riod, Armorlite was forced to act as bothmanufacturer and lab processor. ab duringthat period were neither trained nor equippedto pro s plastic lenses, so the only availapleprescriptions were those that fell withinArmorlite's stock lens range. To produc non­stock corrections, r\rmorlite was the Illysource for surfaced plastic lenses. Eventually,

am had to face a decision. Was Armorliteto e a 'ocessing laboratory or amanufacturer? The company had to decide

Iwhere the' skills re of t value.

Grah cho manufacturing, bettiIi that withplastic lenses now a reality, processing labs forRlastic lenses would spring up. Armorliteclosed their laboratory and, from tha p6ll1ton, devoted the plant solely...to manufacturinglenses with CR-39 resin.

THE START-UP

M LI E L N C '. I

SCRATCHES

The only down side in comparing plasticlenses to glass was plastic's susceptibility toscratching. Armorlite's scientists triedeverything to improve scratch resistance,reviewing more than 2,000 patent abstracts intheir quest for a suitable abrasion-resistant

treatment. The basic problem was thedifference in thermal-coefficient of expansionbetween coatings and lenses made withCR-39® resin. This usually resulted in crazedsurfaces after exposure to temperaturevariations.

In the early 1970s, the famous MinnesotaMining and Manufacturing company (3M)came to the conclusion that they had theanswer. Coatings had always been one of 3M'stechnological strengths, but finding the rightcoating for lenses made from CR-39 resin waseluding even these innovative scientists. Amongtheir researchers' discoveries was that thecleanliness requirements for productioncoating of ophthalmic lenses exceededanything the company had previouslyexperienced. The ultimate answer to thecleanliness problem turned out to be aproduction facility that reduced airborneparticles to a minimum.

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From 1974 to 1976, 3M refined theircoating process. They set up special testlaboratories to evaluate treated lenses. Lenses

that looked fine to the 3M chemists w~rldng

on the project were totally unacceptable to labtechnicians who had a better understanding ofwhat was required. Eventually 3M offered thecoating service they developed to labs in fivestates on a test market basis.

More than 25,000 pairs of hard resin lenseswith the new 3M treatment were sold in thetest market from April 1978 to December

1979. At the end of the 20 month test, 3Mfound that all the test labs wanted to continueselling the coated lenses. Just prior to tltistime, 3M, concluding they had a real handleon the optical business, bought the ArmorliteCompany and transferred the scratch-coatingteclmology to Armorlite. The 3M coatingteclmology was introduced nationally underthe trade nanle RLX Plus®.

When Armorlite was sold to 3M, theoriginal investors who had paid $1.00 pershare for their stock received $4,164.88 pershare under the terms of the sales agreement.

Final insjJection of sellli­finished blan!<s made fromCR-35fJ9 Tesin as they fJass outof the annealing ovenfollowing the manufacturingfJrDcess.

SIGNET UPTOW

Signet ptown was an all-plastic wholesalelaboratory, a rarity at the time the companywas formed. They also casted lens blanks andsoon becanle a major lens manufacturer. By1971, they produced single vision, bifocal andtrifocal lenses, as well as an innovative newpost-cataract lens design called hyperaspheric.

In 1976, the company was sold to AmericanHospital Supply Corporation who sent RichardOrmsby to serve as general manager. In 1981,Ormsby, along with Robert Jepson, purchasedSignet from American Hospital Supply

Corporation. Later that sanle year, Ormsby andJepson also purchased Armorlite from the 3MCorporation. The two companies were mergedto form Signet Armorlite, Inc. From that pointon, the company was an affiliate ofJepsonCOl1JOration. Signet Annorlite was later

purchased from Jepson by the Eagle Corporation.In 1993, Signet Armorlite formed a jointalliance with lndustrie Ottiche Europee. Eachcompany continues to operate independently.

SOLA OPTICAL

Today, SOLA Optical is recognized as one ofthe worl~'s major manufacturers of spectaclelenses, but the company evolved from humblebegimtings. The first experiments of castinglenses made of CR-39® resin in Australiabegan in 1956. The company founders were a

group of men led by oel Roscrow whoworked for a prominent optometric practicenamed Laubman & Pank in the City ofAdelaide. Roscrow and his associates begantheir efforts in a garage by using a gas ring anda saucepan, experimenting in an effort toproduce plastic lenses. Hard resin lenses werejust beginning to make inroads in othercountries, prinlarily the United States andFrance. Tltis small group of Australianentrepreneurs was determined to cast lenses intItis new CR-39 material.

By 1960, Noel Roscrow convinced theowners of the optometric practice to let himspin off his small group and form a newcompany they would call Scientific OpticalLaboratories of Australia (the company nowknown as SOLA). As a means of producingcash flow during those early years, theemployees also performed a number of othertasks. They did binocular repairs for theAustralian army, vacuum coated ophthalnticlenses, made optical instruments and,somewhat incidentally, manufactured all rearvision mirrors used for cars produced inAustralia. Whenever they could steal some timeaway from these tasks, they worked on castinglenses with CR-39 resin. They established abranch in Melbourne in 1965 formanufacturing and repairing instruments butlater converted that plant for the purpose ofprescription surfacing and glass mold-making.

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PLANO LENSES MARKETING LENSES WITH

CR-39® RESIN

Initially, the company concentrated on

casting to prescription completely finishedlenses. They found surfacing and polishjnglenses made with CR-39® monomer difficult, if

not impossible, so casting finished lenses

seemed to be the" ay to go. Gaskets forseparating the molds were made by hand, andthe lens molds were hand filled individually bysyringe. It was a very slow process. eedinganother product, the company began mass­producing plano lenses for sunglass andindustrial use. Manufacturing lenses withCR-39 resin was still a new process, andRoscrow and hjs team had no one to tell themhow to do it.

SOLA concentrated on plano lenses for h\oreasons. First pIanos were easier tomanufacture and the owners believed

producing pIanos would provide training tohelp their people solve the greater problems ofcasting prescription-power lenses. At that timethe common opinion of most casters was thatmanufacturing senti-finished blanks \\ as 10times more difficult than pIanos and makingfinished prescription lenses 10 times moredifficult than senti-finjshed. The second

reason, and perhaps more important reasonfor producing pIanos, was their belief thatbroad distribution of plano plastic lenses bSOLA would help convert the world to thebenefits of these new, lighh\ eight lenses.

To establish plastic lenses as a via~le

alternative to glass, SOLA first had to convincethe eyecare professionals in Australia. One ofthe early marketing promotions the companyimplemented \\ as making thousands of clip-onsunglasses with plano lenses and bundlingthem into batches of five. These bundles \\eresltipped out to hundreds of opticians andoptometrists throughout Australia. One pair wasfree and the other four were billed at a speciallow price. Seventy percent of the retailersreceiving these bundles kept and paid for thesunglasses, 15 percent kept them and didn'tpay, and five percent wrote to SOLA to say howimpressed they were with the company'spositive attitude regarding plastic lenses. Thebalance complained bitterly about the use ofsuch 'cheeky' sales tactics. The end result, ofcourse was a steadily growing acceptance oflenses with CR-39 resin in Australia.

WORLD PRODUCTIO

At this time, there were only threecompmties worldwide making any seriousattempt to manufacture plastic lenses. Thesewere Essilor in France, Armorlite in the nitedStates and SOLA in Australia. For reasons thatno one has ever determjned, each companycarved out their own niche in concentratingproduction efforts. Essilor's efforts were aimedat producing firtished lenses Armorlite

Casting lenses from CR-3gJ9 resinrequires meticulous cleaning andcareJor the jJrecise glass molds inwhich they are cast. JVIclll)' stejJs inthe jJrocess are accomjJlished in a"clean room' environment. In thisjJhotograjJh, trays ojfinished stocklenses are removed Jrom the ovenJollowing curing oj the lenscoating.

concentrated on semi-finished blanks andSOIA zeroed in on plano lenses.

Wlen SOIA began manufacturing senli­finished lenses with CR-39® resin, they founda new problem. Due to the material'sshrinkage when casted, the lens curveschange. In the early days, calculating thecurves that each mold should have to acllievethe desired front curve was an extremelydifficult task. Seven-figure logaritlmls wererequired for the calculations. One of Laubman& Pank's people was a rna ematician who" aspersuaded to join Roscrow's group at SOIA.He was to spend tlle rest of his life calculatingcurves or tlle company's Igrowing asso 'tmentof lenses.

SOLA soon realized that, as big as Australiawas, the Australian market could not supportme kind of manufacturing plant meyenvisioned for themselves. As a result, tlley

focused on export sales. In 1968, a foreignoperation was opened in Japan, expanding inthe early 1970s to the luted Kingdom, Italy,Brazil and finally, the United States in 1975. Bytlus time SOIA had evolved into a globalnetwork of companies. Their senli-finished

'fline was manufactured with a 68 mmdiameter, at that time, the largest availableblanks in the world.

OPENING THE U.S. MARKET

When SOIA came to the Uluted States, theyopened a 15,000 square foot facility inSllI1Jlyvale, Calif. At this time, the U.S. lensmarket was still donlinated by glass lenses,representing 70 percent of the market at thetime SOIA's American plant opened. As aresult, the company's marketing efforts duringthe '70s were devoted to aggressivelyconverting the market to lighter, more impact­resistant lenses. Growing rapidly, the companymoved their .S. manufaculring operations toa much larger facility in Petaluma, Calif., andbroadened the product line. An additionalproduction site was set up in Mexico in themid-1980s.

One of the main linutations in SOIA'sgrowth was the lead time for expanding andmaintaining the wide range of precision molds

required for casting. In 1975 a specialistcenter was established in Singapore to supplyglass molds to plants in Italy, Brazil, the nitedStates and Australia.

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PILKINGTO GROUP

In 1979, SOLA was acquired by thePilkington Group of the United Kingdom. Oneof the reasons for SOLA's remarkable growthwas the U.S. market's shift from glass to plasticlenses. By 1983, the U.S. market was over 50percent plastic and by 1992, more than 80percent. SOLA took evelY advantage of tilisgrowing market.

In 1987, SOLA's parent company, Pilkington,acquired the vision care business owned byRevlon, including Coburn Optical. The formerRevlon operations were operated separatelyfrom SOLA. One exception was the Coburnglass lens business wllich was added to SOLA'sorganjzation.

NEW OWNERS

In 1993 the SOLA Group was purchased byAEA Investors, Inc. Tilis privately-heldcompany, founded in 1968 as AmericanEuropean Associates, Inc., invests insuccessful, industly-Ieading compallies forlong term growth.

Today, SOLA's operations span the globe,operating 12 manufacturing sites on fivecontinents with sales offices in 16 countries.EvelY 'week, SOLA customers, located in some

70 nations, order more than one millionlenses. The company estimates that more than

one hundred million people around the worldare wearing SOLA lenses today. Even thoseoptimistic dreamers in Adelaide couldn't have

foreseen what w~uld result from those primitiveattempts to make plastic lenses in a garage.

Essilor Int"ernat"ional

To understand Essilor's role in thedevelopment of plastic lenses, it's necessalY toreview the origins of what has become thelargest optical company in the world.

ESSILOR FAMILY TREE

The Lissac Company was founded in 1931by George Lissac, an entrepreneur whointroduced marketing to the conservativeEuropean optical industry. Lissac later createdSlL (Societe Industrielle de Lunetterie) in1946 and a separate company, LOS (LentillesOphtalnliques Speciales), in 1948. These twocompanies included frame and lens researchand development, manufacturing anddistribution operations. SIL, the frame division,created the revolutionaLy AMOR rimless framein 1949. "AMOR" is a condensed version ofthe French word "amortisseur" wllich meansshock absorbing.

Rene Grandperret, with LOS, developed anearly interest in plastic lenses, dating back tothe late 1940's. In 1952, LOS introduced the

d

ORMA® 500 lens made from Plexiglas® resin,

marking the beginning of plastic spectaclelenses in France. Lenses made from Plexiglasresin were only marginally successful becauseof the familiar problem of scratching. LOSeventually found what they decided was theideal resin in the United States and beganexperimenting with PPG's CR-39® monomer.

After years of continuing research, LOSeventually mastered the difficulties of casting

lenses from CR-39 monomer and introducedthe ORMA® 1000 lens with CR-39 resin in

1956. This lens was patented and introducedworldwide in 1959. The following year, thename of the lens division was changed fromLOS to LOR (Lentilles Ophtalmiques

Rationnelles). By 1961, SIL had introduced thepolymil frame. In 1966, the Lissac groupmerged with Telegic, a company specializing inthe production of corrective lenses. Then in1969, Lor-Telegic joined the other division ofthe Lissac group, SIL (Society Industrial deLunettegy) to form a French company with thenow familiar name of Silor. ORMA 1000 lensesmade with CR-39 resin were introduced in theUnited States by Silor's American subsidiaty, LaLunette de Paris.

ESSEL

Meanwhile, another significant Frenchcompany, Essel, began to use the company'sname in marketing ylor® frames, an

inlproved version of the AMOR

frame created by Lissac in 1955 andVarilux® optical lenses, introduced in

1959. Essel was formed in 1848 inFrance during the Spirit of LaborCooperation, the revolutionary sociopoliticalworker's cooperative. In 1955, Essel createdthe ylor frame which enjoyed huge success.The cash flow generated by ylor frameshelped finance the Varilm~® I optical lens.

The "marriage" of these two companies(Silor and Esse}) brought together recognized

ophthalmic brand names ( ylor, AMOR,Varilux I and ORMA 1000), research anddevelopment teams, and major manufacturingand distribution networks. The two mostimportant optical companies in France mergedto become Essilor International.

PLASTIC LENSES

The company's first successful correctivelenses were cast on April 29, 1954 by BernardMignen when he successfully polymerizedlenses with CR-39® resin in glass molds. Hisexperiments took place in the kitchen of afactOly in St. Maur, France, which had beenrecently purchased by Georges Lissac. Earlyefforts were unproductive, primarily becauseof problems with breakage of the glass moldsand great difficulty in separating lenses fromtheir glass molds. Eventually, in 1959, thecompany successfully launched commercial

The introduction ojlightweight lenses madefrom CR-3~ resin had amajor imjJact on eyeglassframe Jashions. As the lensesgrew in jJoplilarity, so didthe size ojframes and beforelong, stylish oversizef!)'egla ses became the leaderin f!)'ewearJashions.Attractive f!)'ewear like thatworn b)' the model wouldhave been imjJossible withglass lense .

•

production of lenses made with CR-39® resinunder the trade name ORMA® 1000. That

became possible when Jean Boudet andBernard Mignen developed an improvedmolding process.

EARLY ATTEMPTS

In 1941, Rene Grandperret, 20 years oldand a new employee at Lissac Brothers, visited

a laboratory in Colombes, France, where twoengineers with the lational Conservatory of

Careers were trying to produce lenses made ofPlexiglas® resin cast in molds instead of using

heat compression. They used spring-actuatedmolds that allowed the mold walls to followthe retraction of the Plexiglas resin as itsolidified (the material shrank 22 percentduring polymerization).

SECOND ATTEMPT ­

SU NGLASS LENSES

Following World War IT, Georges Lissacbegan producing sunglasses using lenses madeof Plexiglas® resin. In 1946, Sovis, a branch ofSaint-Gobain, transformed sheets of coloredPlexiglas resin into sunglass lenses by cuttingthe sheets into circles which were then heatedand pressed into plano lenses. Because thelens surfaces were parallel, tllis was arelatively easy way to produce lenses made ofPlexiglas resin.

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THIRD ATTEMPT - PLEXIGLAS®

RESIN MOLDED THROUGH HEAT

The IGard® lens process involved ~heets ofPlexiglas® resin that ,,,ere compressed in

heated iron molds. Alicense for tltis processwas granted in 1937 to Peter Koch of Goreyn.Tllis was the process used by COIL in England.In 1946, another license was requested byArthur Kingston who also experimented withPlexiglas resin and polystyrene. Georges Lissacwas ulitially in favor of negotiating a license formolding lenses made from Plexiglas reSUl butchangedltis mind after talking to enguleerswho described the process used by COIL. Hedidn't believe the COIL process was sufficientlyumovative. In 1950, a mechaIlic naInedBorulion received approval from Lissac tobegin production of lenses made fromPlexiglas resin. The lenses were reasonablyunpact-resistaI1t but very susceptible toscratching aIld yellowing with age. These earlyplastic lenses, called ORt\1A® 500 lenses, wereused primarily for children.

CR-39® RESIN - MILITARY

AND OPTICAL USES

One day GraIldperret received a transparentsheet that seemed to have interestingmechanical and optical properties. Thematerial had good traI1Sparency and resistaIICeto scratclting 40 tiJnes that of Plexiglas® resin.The commercial name was Homallte®, and itwas made of CR-39® resin. The material hadbeen used as windows for AmericaIl taIlksduring the war. In 1953, Grandperret ordereda half liter of CR-39 reSUl for experiments.

The Men Who MadeLenses With CR-39®Monomer A Reality

Robert K. Graham grewconvinced that jJlastic lellseswere jJossible while workingJor Univis Lens Compall}

That vi ion became a realitybut 0111) after )'ear oj

heartbreakingJailures andcountless nights oj listening

to the sound oj breal<ingmold caused by heat from

the jJolymerizillg process.

"t\oel Roscrow was making plastic lenseson a gas ring in a garage when he andhis grou.jJ Jormed Scientific OjJticalLaboratories ojAustralia, the companyIwowll worldwide today as SOLA. Uponhis retirement, Chainl/anDavid L. Pankcredited Roscrow's mix oj knowledge,entrejJreneurial drive, energy and sheercheell as contributors in helping achievethe comjJany's success.

Rene Grand/Jerret was 20 )'ears old when hefirst became involved in an attemjJt to/Jroduce lightweight lenses from Plexiglaresin in 1941. Twelve years latel; hediscovered some interesting sheets ojtrans/Jarent material that had been 'Used inAmerican tanllS during World Har II Thematerial was made oj CR-39'J9 resin, a nd heimmediately ordered a half liter oj materialfrom ppc. Two )'ears later Lissac wasmailing sun lenses Jrom CR-39 monomel:

THE FIRST LENS MADE WITH

CR-39® RESIN

Saint-Gobain accepted an order to delivercircular blanks made of Pyrex® glass for usein building molds. Plastisol was used formaking gaskets to hold the molds. The processof polymerization was new to Grandperret'speople, and initially, all the cast lenses brokeduring polymerization due to lack ofventilation. They soon discovered they had tofind a way to control the rise in temperature

during polymerization. If the temperature rosetoo much, the lenses turned yellmv and broke.On April 29, 1954, for example, they producedthree good lenses and one broken lens.

Pittsburgh Plate Glass Co. referred them to twopeople who had been working on plasticlenses for several years. One was a man namedJolm O. Beattie; the other was Robert Grallatllin the United States. In June of 1954,Grandperret spent three weeks in the UnitedStates learning the methods being used byGrahatll.

SOLAR ORMA® 1000 LENSES

In 1955, IJssac, Inc. decided to make sunlenses of CR-39® monomer. The resin wasordered a,nd production methods similar tothose observed in the United States wereinitiated. There were still problems controllingpolymerization, but eventually these were

resolved. nfortunately, they had homogeneityproblems in the first batch of sun lenses. 1heresult was a variation in color.

ORMA® 1000 LENSES ­

THE ULTIMATE GOAL

In the meantime, matlY production methodsfor casting lenses with CR-39® resin weretried. One was suggested by Jolm O. Beattiewhich involved partially polymerizing the lensand removing it from the mold to continuepolymerization in a large pan. Later,polymerization in the mold was tried. Generalconsensus deemed that molding lenses with

CR-39 resin would never be adaptable tobifocals. By this time, both the English atld theFrench were convinced that the ultimateanswer would be a lens made of Plexiglas®

resin covered with a veneer of CR-39 resin forscratch protection. Gratldperret tried aradiochemical process for linking Plexiglas

atld CR-39 resins but the resulting lenses wereunsatisfactory.

By 1959, however, the company successfullyproduced ORMA® 1000 lenses with CR-39

resin. In the early 1960s, the COmpatlY beganexporting lenses to Germatly, Spain, Italy andSwitzerland. In Great Britain, ORMA Optical

opened in 1965 to produce prescriptionorganic lenses. The company's major success,however, was in the United States. Aproduction platlt under the name Silor openedin Florida in 1972. This facility wouldeventually become the largest producer oforganic lenses in the world.

•

PART THREE

OPTICAL LABORATORIES

Converting lens production from glasslenses to casting lenses from CR-39®monomer involved a variety of newtechnologies for lens manufacturers. It alsorequired new equipment and new employee

skills. For a number of years, most lensmanufacturers maintained two diverselydifferent production lines, one for glass andone for plastic. As lenses made from CR-39resin came to dominate the market, lensmanufacturers began dropping out of the glass

market altogether.

Tllis changing market impacted opticallaboratories in even more dranlatic ways. Atthe tinle Armorlite began producing lensesmade from CR-39 resin, no labs had the abilityto surface plastic lenses. During the late 1940sand 1950s, a few progressive laboratoriesdistributed I-Gard® acrylic stock lensespurchased from Mcleod Optical (see "PlasticLenses," page 10). Labs learned to edgeplastic lenses, but they had no experience withgrinding and polishing them. Armorlite, thefirst successful manufacturer of plastic lenses,eventually (and secretly) set up a surfacing

laboratory to provide practitioners withsurfaced lenses. Armorlite was convinced tlliswas the only way they could create a marketfor their new plastic lenses.

THE PIED PIPER

By now, laboratories began to receive

occasional orders for post-cataract la,l1sesmade from CR-39® resin. It seemed obviousthat labs would eventually have to surface thisnew material. As it turned out, the role ofconvincing and teaclling labs to process lenseswith CR-39 resin fell in the unlikely hands ofan ex-Canadian Air Force World War II pilotnamed Forbes Robertson. Robertson was hiredby Armorlite in 1959 to sell the company'slenses. Iilitially, llis job consisted of detailingdoctors for ordering plastic lenses. The factthat many of the lenses Armorlite sold weresurfaced in their lab was, for the most part, adark secret. Robertson grew convinced thatthe only way to build national demand forlenses made from CR-39 resin was to get labssurfacing plastic lenses as quicldy as possible.His was a minority opillion at Armorlite, buteventtlally he prevailed and was authorized toshow lab owners how to process lenses with

CR-39 resill. Soon he began calling on evelYmajor laboratOlY ill orth America, hying toestablish a market for Armorlite senli-fulishedlenses. Fil'st, he had to teach labs how tosmface plastic lenses. His sample bag consistedof a few senli-finished blanks and a box of tin

oxide.

It was the desire for lightweight, lligh plus,post-cataract lenses that created illitial interestin lenses made from CR-39 resin. This came

Forbes Robertson was convinced the onlyway to malle lenses with CR-3919 resinsuccessfu.l was to get laboratories involved.The hundreds of sales lJitJS he madecan)lingfew lens blanlls and a can of tinoxide resulted in JJwn} major wholesalelaborat01ies biting the bullet and becominginvolved in plastic lens jJroduction.

•

mostly from large wholesale and retailorganizations such as Benson Optical,

Uhlemann Optical and others who had largenumbers of ophthalmologists as customers.Ophthalmologists wanted their patients to havethe new lightweight cataract lenses theylearned about at the Academy ofOphthalmology (from Armorlite's Bob Graham,

who lectured on lightweight lenses made fromCR-39 resin at Academy meetings).

Among the first companies to take upplastic surfacing at Robertson's urging wereUhlemaIU1 Optical and Boll & Lewis, twoprominent Chicago retail orgaIlizations, andWllite Haines, a major wholesale laboratorychain based in Ollio. Around that same time,Robertson heard that the three partners atParaIll0unt Optical in SaIl FraI1Cisco werebreaking up, and one planned to set up a

laboratOlY in PortlaIld, Ore. He flew toPortlaIld aIld called on Lawrence "Larry'Wheelon. He gave Larry and llis partners, Otto

Wagner and son Robert Wheelon, llis standardpitch on the advaIltages of processing plasticlenses, aIld left town without knowing whetherllis sales efforts worked.

1\vo weeks later he received a call fromWheelon with the astOllishing. news that thepartners decided their new lab, called Opti­Craft, would process only plastic lenses. LanyaIlIlounced that he and llis partners WaIl ted tocome down to Pasadena aIld spend a week

The only source for teclmical hel

time was Armorlite, and it turned out tnat theyhad only just started surfacing. In Wheelon swords, it was "the blind leading the blind."During llis visit to Armorlite, Wheelon toldGrahaIll he waIlted to be GrallaI11'S bestcustomer. Grallam responded by offering llima job, but Wheelon decided that Pasadena wasno substitute for the natural charms of thenorthwest and PortlaIld. He returned toOregon, and Opti-Craft soon becanleArmorlite's best customer. Opti-Craft's salesefforts, in effect, opened up the whole WestCoast for Armorlite. Other wholesalelaboratories began surfacing plastic lenses intlle hopes of salvaging business tlley were losingto Opti-Craft. (See "The First All-Plastic Lab,"

page 30)

LENSES MADE FROM CR-39®

RESIN INTRODUCED AT THE OLA

The 1961 Optical Laboratories Association(OLA) convention in Chicago was a majorevent for Robertson. This would be the labs'

illitial introduction to lenses made from CR-39resin. Sillce Armorlite hadn't sold senli­filushed lenses before, there was a madscraIllble to get lens boxes printed so thelenses could be displayed at the OLA ill a

•

.~

reasonably professional way. On the way to theLos Angeles airport, Mrs. Robertson hung overthe back of the car seat tlying to match andinsert lens blanks into the proper printedboxes. She managed to sort the lenses and boxthem by the time they reached the airport. ThatOLA convention paved the way for theindustry's slow transformation from glasslenses to lenses made from CR-39® resin.

OTHER LAB EXPERIENCES

Another early convert who responded toRobertson s sales efforts in a positive way was

Bill LowLY of LowLY Optical in Florida, a lablater acquired by Milroy. Aggressive labsacross the countLy began experimenting, tryingany way they could think of to surface plastic(some ways were rather bizarre). William C.Seibert, owner of Three Rivers OpticalCompany in McKees Rocks, Pa., remembers

those days well. In the mid-1950s, he workedfor American Optical as a lab supervisor. Mostmachinely used in American Optical labs wasmanufactured by AO but was hardlyconsidered state-of-the-art, even for that day.

As demand for lenses made from CR-39® resinincreased, American Optical fell behind

independent labs in processing plastic lenses.Seibert remembers the tortures of tlying todevelop techniques for grinding plastic lenses.

Wire mesh pads were tried with 145 gritemery, resulting in 30 minutes fining for eachlens. Polishing was done on white felt pads.

•

Seibert's Anlerican Optical branch never didreach a point where they could produce plasticlenses with the ease of glass. Problemscontinued in one form or another until

1975-76 when American Optical installedCoburn surfacing equipment. Even with thenew equipment, they were still plagued withwaves and distortion. Evennlally theydiscovered a yellow felt pad from Econ-o-cloththat worked. They tried one-step pads,

two-step pads and even diamond pads. It was aconunon experience to produce one good lensand discover they were unable to repeat theprocess for the other eye. Lenses ended upwith gray edges or swirl marks. It wasn't at all

unusual to produce a good-looking lens thatcouldn't be read in the lensometer.

DIFFERENCE BETWEEN

GLASS AND PLASTIC

Most surfacing problems were created, inSeibert's opinion, because labs wanted toprocess plastic the way they did glass.Surfacing blocks were small in diameter anddesigned for glass, offering no support beyondthe center of the lens. Plastic lenses flexedduring surfacing, creating multiple waves anddistortion. Sales engineers at Coburn Opticalwere helpful during this period, but evenCoburn was feeling their way in this new field,much like their customers. Eventually, Coburncame out with larger blocks and eliminatedone cause of distortion.

POST-CATARACT LENSES

Agood set of glass molds, however, could

replicate the most sopltisticated asphericcurves over and over in CR-39 resin. It wascomparatively easy for labs to convincedoctors arld consumers of the advantages oflightweight plastic lenses for cataract patients.Labs found this a ready market arId beforelong, labs were scattered around the countrythat routinely surfaced plastic cataract lenses.Expertise gained with cataract lenses helped

establish plastic lenses for all patients.

The fate of glass lenses was largely sealedwhen the Food and Drug Administration (FDA)decreed in 1972 that all glass lenses sold in

THE FINAL STRAW

lltitially, labs concentrated their plasticproduction on producing post-cataract lenses.Plastic lenses were too new arId too prone toscratching for most patients. With post-cataractpatients, it was a different stOlY. During thatperiod before the development of inter-ocularlenses, two factors made lenses casted fromCR-39® resin an ideal lens for post-cataractpatients. The first was weight. Strong pluslenses of IOta 14 diopters were eX1remelyheavy when made up in glass, a situation thatconcerned every wearer of these awkwardlenses. The second factor was the recentdevelopment of sophisticated aspheric post­cataract designs that proved extremely difficultand costly to produce in glass.

One day Forbes received a call from Allan

Kosh, father of Jeff and Stuart Kosh. KoshOptical (then in ew York City) had been arlearly convert to CR-39® resin. Allan calledcomplaining about a rash of surfacingproblems that had recently cropped up. Forbessaw on TV that morning that a heat wave hadltit ew Y~rk City. He asked Allan if he air­conditioned the lab as he had prontised. Theanswer was," at yet. We have the equipmentordered but it s not installed. ' Forbesreminded ltim how heat affected plasticsurfacint eedless to say, Allarl quickly hadthe air conditioning equipment installed.

Forbes Robertson was convinced that plasticlenses would only succeed if labs couldprocess them on equipment they alreadyowned. The problems carne in convincing labsthat to do this, they had to completely cleanthe existing equipment and maintain a degreeof cleariliness they weren't used to. Labs in theearly 1960s looked far different tharl today'slabs. Robertson's greatest problem was simplytheir dirty condition. He undoubtedly offendedsome labs when he told them, "The first thingou have to do is clean up." Another issue was

that t created many problems related to

~.~&lJl~;ag plastic. Air conditioned labs wereco paratively rar that tinle, arld Robertsoncontinually ur that plastic production lines

e ·tioned. Eventually, tItis wasced labs. They begarl totic on separateair conditioning for the

Lenses made from CR-3939 resin were themajor influence on e;eglass fashionsduring the seventies and eighties. Theirlight weight made stunning oversizeframes a reality. The profusion of solidand gradient tints of ever)' hade andhue that could be jJroduced throughartistic tinting of the lens made those),ears unforgettable to those who livedthrough them.

•

THE FIRST

ALL-PLASTIC LAB

In June, 1962, Lawrence Wheelon, anexperienced lab man with more couragethan most lab people of that day, decidedthere was a rosy future for plastic lenses.Wheelon had an aunt who underwentcataract surgelY at the University ofWashington. Her new plastic cataract lenseswere ordered from Armorlite. It took threemonths to get them. WheelQn decidedanything that difficult to obtain would be agood business to get into. Along with IllS wife;IllS son Bob; Steve Willtman, an experiencedlab man who had worked for Riggs Optical;and Otto Wagner, an experienced surfaceman, Wheelon set up a new laboratOly inPortland. Equipment was purchased from arecently-closed lab in Montana.

Wheelon initiated a relationship with PPGand investigated the possibilities of castinglenses. By the time PPG engineers pointedout all the ramifications required to castlenses, \Vheelon decided it made more senseto fabricate lens blanks cast by someoneelse. FolloWing a sales call from Armorlite'sForbes Robertson, he flew to Pasadena andmet with Bob Grallanl. When the Opti-Craftlab opened, they made lllstory by beconllllgthe first plastic-only laboratOly.

Footnote: CustOtners liked Opti-Craft'sservice and wanted to order all theirlenses from the same source. Thesedoctors weren't, howeveJ; ready to switchfrom glass to plasticfor conventionallenses. Within ayeal; Opti-Craft facedreality and set up a separate division forprocessing glass lenses. As the yearspassed, howeveJ; Opti-Craft eventuallyconvinced customers ofthe advantages oflenses madefrom CR-39® resin, and thecompany became a leading laboratoJJ onthe West Coast. They are presently part ofthe Omega LaboratoJJ' Group, a divisionofEssilor ofAmerica. For slightly less thanayeal; however Opti-Craft was the onlyall-plastic lab in the UJorld.

•

the United States would have to be a minimumof 2.2 mm at their thinnest point, be heat­treated or chemically tempered and pass adrop ball test performed by the lab 011 theperson edging the lenses. Previously, mostglass lenses had centers or edges (dependingon the power) well under 1.5 mm, some withcenters as thin as 1.0 mm. Tllis new rulingeffectively meant that glass lenses would be 30to 50 percent heavier than in the past.

Tllis couldn't have happened at a worsetime for glass because frame styles were juststarting to grow in size. These factorseffectively combined to give lenses made fromCR-39®monomer the boost that would

ultimately make CR-39 resin the dominant lensmaterial in the United States. The rest, as theysay, is llistory.

Dwing the seventies and eighties, theone item on evelyone's "olJtical wishlist" was a lightweightjJlwtochrollliclens that would work. SeveraljJromisi'l'/'gphotochmmic jJlastic lenses showed ttjJdUTi'ng the eighties but none oj themsatisfied the jJroJessions' eXjJectations. Ittool< the introduction oj Tra:nsitionS®lenses in 1991 to satisf)' the need.Instead oj replacing glass photochromiclenses (less than 10 jJercent oj themarl<et), Tramitions lenses 'replacedcosmetic tints, 1lsheling in a totally newcategol)l ojjJremill:m lens Jor the eyecarejJroJessions.

The St-ory ofP hot-ochro7nicPlast-ic Lenses

THE CONTINUING EVOLUTION

OF CR-39® RESIN

Almost from the day photochromic glasslenses were first introduced, lensmanufacturers received requests for aphotochromic lens made in a lightweightplastic. From the mid-sixties on, evel)'gathering of optical people would usuallyinclude discussions of, "When are we going tohave plastic photochromic lenses?" During theentire fifty years CR-39® resin has been usedfor ophthalmic lenses, PPG researchers havecontinually searched for ways to increase itsversatility. The most dramatic result of thiscontinuing research was the development of an

effective photochromic process based on avariation of CR-39 resin called CR-307™monomer. The StOl)' of how the Transitions®

lenses process evolved is best told in timelinefashion, beginning in 1973.

1973

The first reported work on photochromicsby PPG takes place at the cOQ'lpany's BarbertonTechnical Center in 1973. From then until1980, photochromic research & developmentbecame part of a number of different CR-39®monomer projects. These efforts remained

comparatively low-key, and no synthesis of newcompounds was involved.

1981

American Optical introduces their Photolitelens. The industt)' excitement prompted by thisproduct release galvanized the scientists at PPGinto another flurry of photochromic research.The American Optical lens turns out to be acommercial failure because of poorproperties, short lifetime and an unattractiveblue color. Anew specialist with a backgroundin photocluomics is added to PPG's staff, andsynthesis of new photochromics combinedwith testing of known photochromics in matrixfrom CR-39® monomer begins.

1983 - PVRIDOBENZOXAZINES

This year is a photochromic milestone

because of the discovel)' of a new family ofphotochromics called pyridobenzoxazines.This year also marks the discovel)' of theunique inlbibition process for incorporatingphotoclu'omic properties in polymers andcopolymers made from CR-39® monomer.

1984

PPG starts a joint venture with Intercast­Europe to manufacture and sell photochromicsunlenses called Attiva. These are stillmanufacnlred by Intercast, using PPG's blue

•

photochromics. Research in this teclmology

continued, and by 1985, production of Attivalenses reached 3,150 per day. In 1986,marketing of the Visenza lens, an all-PPGventure, begins. Avariety of prototype lenssystems were produced and tested on PPGemployees and consumers during the next

three years.

1986 - TRANSITIONS

PPG authorizes $1 million for testing thetechnical and marketing feasibility of plastic

photoclu'omic lenses. Between July 1987 andMay 1988, the company assesses theacceptance of prototype lens systems throughemployee and consumer use tests. In the fall of

1987, 30 persons wear the lenses for onemonth. Atypical comment about thoseprimitive lenses comes from one wearer, "Theyworked pretty well... could get a lot darker,and, boy, are they an ugly yellow in the

bleached state." In 1988 a pair is given toanother employee to wear on a trip to Hawaii.His comment: "If you can't make them get anydarker, you're out of business." Additional

consumer-use tests are conducted inMitmeapolis, Miami and San Diego, andgradually, the consumer responses improve.

•

1988

On May 1, PPG gives the go-ahead to

proceed to the next step which cons~sts ofsetting up test markets for the newphotochromic lenses. This is considered amilestone by the company's ophthalmic

photochromics group, and a special picnic isheld at Lake Dorothy, Ohio, near PPG'sBarberton Technical Center. Eighty-eightpeople show up for a special catered meal ofbarbecued ribs. Shortly after the picnic, PPGProject Director John Crano hand-carries 100lenses to Vermont and southern ewHampshire for the first tests. Later, additionaltest markets are established in Memphis andPittsburgh.

1990

Substantial progress is made, and by 1990,Transitions Optical Inc. (TOl) is formed and amanufacturing facility established in PinellasPark, Fla., for producing photochromic lenses.By this tinle, PPG invested more than $8.5million in developing the new Transitions®

photochromic lens.

To firm up the industry's shaky confidencein such a new technology, TOI wisely decidesto offer a patient satisfaction guarantee on

their new lenses. During the first three years of

distribution, their return rate runs less thanone percent, a remarkable record for such anew technology.

The technology used to producephotochromic plastic is totally different fromphotochromic glass. The chemistry is based onorganic, rather than inorganic, compounds.When Transitions® lenses are exposed to theultraviolet rays in sunlight, the photochromic

compound is activated to a form that absorbsvisible light, causing the lens to darken. Whensunlight is removed, the photochromiccompound converts back to its colorlessform, and the lenses return to their originalclear state.

Other plastic photochromic lenses haveeen introduced, but none have enjoyed theccess of Transitions comfort lenses, dating

to their introduction in 1990. Transitionsare made of a lightweight polymer,to CR-39® resin.

While their technologies are completelydifferent, photochromic glass andphotochromic plastic share certainharacteristics. Both are activated by the

violet component of the solar spectrum.Both photochromics are temperature­dependent. Another distinct advantage ofphotochromic plastic compared to

photochromic glass is that Transitions lensesdarken uniformly, regardless of the

prescription of lens design. Thicker portionsof photochromic glass lenses darken more

than thin areas, creating an unattractive,uneven density.

1992

The first Transitions® lenses formulation isreplaced by the new Transitions® Plus. This

second generation provides greater activationspeed, darkening more and faster than the

original lens. In 1993, Transitions Plus lensesreceive the prestigious Optical LaboratoriesAssociates (aLA) Award for Best Lens Treatment.

1996

The newest generation of Transitions®

lenses is unveiled to the eyecare professionthrough a series of galas held in major U.S.cities. The result is overwhelming approval ofTransitions® III lenses which darken faster,darken more and achieve a true gray colorthat most consumers prefer. This newest Talproduct is also available in a mid-index,opening a totally new market forphotochromic plastic lenses.

•

THE END (NOT YET IN SIGHT)

THE IMPORTANCE OF

POSITIONING

At the time Transitions® comfort lenses\\ere introduced the lens market in the

nited States was approximately 80 percentplastic and 20 percent glass. Half of all glasslenses sold were photochromic. With theintroduction of Transitions len es manydoctors and dispensers assumed the marketfor these new lenses would be those patientswho had been \\ earing heavy photoclu'onlicglass (10 percent of the market).

Marketing people at TOI thoughtdifferently. "Go after the consumers whoalready wear plastic lenses (80 percent ofthe market), and go after those who wearfixed tints (60 percent of the market) , wastheir advice. That huge untapped segment ofthe market hlrned out to be exactly right forTransitions lenses. Further, offering theseconsumers photochromic lenses opened upa completel) new premium lens market forthe eyecare profession. The rest is historyTransitions lenses hlrned out to be the mostsuccessful and fastest-growing segment ofthe entire premium lens field all madepossible because of proper positioning of abrand new technology.

•

With the experience of fifty years of majorparticipation in the ophthalmic len~industry

what does the future in this important segmentof the health care industry hold for PPG?

Some industry observers have tracked thesteady growth of alternative plastic lensmaterials such as high index and polycarbonate,and have predicted a gradual decline of marketshare for lenses made of CR-39® monomer.Executives in PPG's optical products business

are quick to point out that the market for lensesmade of CR-39 resin has never been stronger.Willie usage in the nited States has flattenedsomewhat, continuing conversion from glass to

CR-39 resin is rising dramatically worldwide.They remind listeners that major highly­

populated countries such as India and China arejust at the threshold of a major conversion fromglass to plastic. The general expectation is thatthis trend added to all the third-world countriesentering a similar conversion phase predictshealthy increases in worldwide sales of lensescast from CR-39 resin for years to come.

John Crano, PPG s associate director ofoptical products, was asked recently what hesees in PPG's future for the optical productsbusiness. ' Our initial major contribution to theophthalmic industty was the development ofCR-39® monomer-chemistt) that ultimately

The one individual at PPC who wasjJersonally involved in the quest for ajJhotochromic plastic lens from the verystart wasJol1l1 Crano. Once his re earchchemist were convinced that they hadfound the answel; a jJrimitive j)roductionline was set 1Ij), andJohn j)ersollallycarried the first 100 lenses jJroduced toBeta Site Labs in Vermollt and ewHa mjJsh ire.

-

became the major substrate for ophthalmic

lenses in every developed countty. PPG s

continuing investment in technology led to thedevelopment of photochromic Transitions®

lenses. This lIe\\ technology has ah'eady

proved to be a major profit contributor for the

eyecare professions.'

To quote Peggy Lee, Dr. Crano was asked

, Is that all there is?' He laughed and

proceeded to project. some of the areas inwhich he believes PPG \\ill playa major role.

Dr. Crano contemplates higher index materials

for Transitions lenses and suggests those could

include polycarbonate. There is a viable

market for more easily cured high indexsubstrates utilizing ultraviolet (UV) light for

curing. This is an area that will certainly be

considered. Development of -cured high

index resins will lead to more cost-effective

manufacturing and this will ultimatel benefit

eVel)One in the supply chain from

manufacturer to consumer. The development

of modified CR-39 resins that will produce

thinner lenses in 1.50 index with improved

impact resistance are definitely under

consideration.

Whether Dr. Crano's predictions come to

pass or not, PPG Industries llfs proven thevalue of their contributions to the eyecare

professions and the spectacle-wearing public

during the past fifty) ears. It \\ ould be

fascinating to have the abili~' to project into

the year 2047 and observe how PPG celebrates

the lOath amllVerSal)' of their majorcontribution to mankind and the field of

ophthalmic optics.

PPC headquarters are based ill the world­Ja11l0u ix-buildillg gla c011l/Jlex located atOlle PPC Place ill Pittsblllgh. O/Jelled ill 1983alld de iglled b) rellowlI architect Phili/JJohll 011, thi totally ellerg)'-eJJiciellt buildillg habec011le a Pellll )'Iva Ilia la lid11Iarl<.

•

THE EVOLUTION OF LENSES MADE WITH CR-39® MONOMER

1938

1937

1941

1940

Combined Optical In@lstries Ltd. (COIL) starts production of IGard® lenses made fromPlexiglas® resin. ~

TULCA (The Unbreakable Lens Company of America) begins producing injection-molded

lenses made from PMMA.CR-39® monomer developed by research team at Columbia Southern ChemicalCompany, a wholly-owned subsidialY of Pittsburgh Pla~ Glass Co. (now PPG).PPG researchers discover CR-39 resin and apply for patent. They discover the materialcan be combined with paper, cloth, pigments and other materials, and molded intofinished, shaped, laminated products.CR-39 resin used for producing transparent gauge tubes in aircraft to prevent breakageand fuel spills associated with glass tubes.France's 'ational ConservatOlY of Careers tries casting Plexiglas resin in spring-actuatedmolds.CR-39 resin first used for reflector and searchlight applications.CR-39 monomer patent awarded to PPG's Irving E. Muskat and Franklin Strain.Univis closes their plastic lens division.Robert Grahanl and ex-Univis team move to California.Lissac produces sunglass lenses from flat circles of Plexiglas resin pressed into

plano lenses.Armorlite Corporation forms and begins experinlenting with CR-39 resin.McLeod Optical becomes exclusive .S. distributor for IGard lenses.Lissac sets up to produce lenses made from Plexiglas resin in France.LOS introduces ORMA® 500 lenses made from Plexiglas resin in France.Lissac's Rene Grandperret orders a half liter of CR-39 resin for experiments.Grandperret spends three weeks in the .S. with Robert Grallam.Lissac's Bernard Mignen successfully polymerizes lenses made from CR-39 resin.Lissac, Inc. makes sun lenses from CR-39 monomer.ORMA 1000® lenses made from CR-39 resin introduced worldwide.

First plastic bifocals are cast.SOLA Optical formed and begins producing lenses made from CR-39 resin in Australiawith 10 employees.

1961-66 SOLA begins exporting lenses made from CR-39 resin to Japan, England, France, Italy,India and other countries.SOLA's Japan operation opens (the first totally foreign-owned operation in Japanfollowing World War II). SOLA introduces Spectralite® optical lenses, the firstphotochromic high index lens.

1968

194719491950195219531954

19431946

195519591960

•

1969 La Lunette de Paris introduces ORMA® 1000 lenses to the United States.Lenses made from CR-39® resin tested on U.S. pilots.

1970 SOLA's UK operation opens.1971 Food & Drug Administration passes impact-resistance regulations for

eyeglass lenses.Signet Uptown begins casting bifocals, trifocals and post-cataractlens blanks.

1972 Silor opens lens casting plant in Florida.1973 PPG's Barberton Technical Center conducts the first photochromic

experinlents with CR-39 monomer.1974 3M develops scratch-resistant coating for lenses made from CR-39 resin.1975 Lenses made from CR-39 resin now account for 15 percent of all lenses

in the U.S.SOLA opens operations in U.S.

1976 SOLA begins casting lenses in the United States.1978 Armorlite Corporation sold to 3M.1979 SOLA is acquired by England's Pilkington.1981 Signet and Armorlite are merged into Signet-Armorlite.

American Optical introduces Photolite photochromic lenses.1983 PPG discovers new fanlily of photochromics, the blue pyridobenzoxazines.1984 PPG forms joint venture with Intercast-Europe to manufacture and sell

photochromic sunlenses called Attiva lenses.1986 PPG starts a one year $1 million program to test technical and marketing

feasibility of plastic photochromic lenses.

1987 PPG launches employee and consumer use test of prototypephotochromic lenses.

SOLA acquires Coburn lens business.1988 PPG researchers at the company's technical center in Monroeville, Pa.,

produce a prototype of a plastic photoclu'ornic lenses, a precursor toTransitions® comfort lenses.

1989 Transitions lenses introduced in test markets - Vermont, ew Hampshire,Memphis and Pittsburgh.

1990 Transitions Optical Inc. (TOl) is formed as a joint-venture between PPGIndustries and Essilor International, and begins manufacturingTransitions lenses.

1992 Researchers in Monroeville develop Transitions® Plus comfort lenses, afaster acting photoclu'omic lens.

1993' TOI opens sales and marketing office in Paris.1994 Transitions Optical, Ltd. opens a new plant in Thanl, Ireland, to supply the

European market.SOLA introduces Spectralite® optical lenses, the first photochromic high

index lens.1995 TOI begins construction of fnanufacturing facility in Australia and opens

sales office in Brazil.1996 The third generation, Transitions® ill lenses, is introduced in Spectralite

lens and 1.56 high index.1997 PPG celebrates the 50th anniversary of lenses made from CR-39 resin.

2639B 25M 0497CR-39 is a registered trademark of PPG Industries, Inc.

PPG Industries, Inc.One PPG Place

Pittsburgh, Pennsylvania 15272-0001 USA