aerosol containers
DESCRIPTION
aerosol can, spray, how deo worksTRANSCRIPT
Submitted To: - Submitted By: -Mr. Madhab Chakraborty SandeepDeputy Director Roll No. 1116IIP 1st Sem, 27th BatchDelhi IIP, DELHI
What is Aerosols and Aerosol Spray?
An aerosol is a suspension of fine solid particles or liquid droplets in a gas.Example: - Smoke, smog, mist from an aerosol can etc.
Aerosol Spray is a type of dispensing system which creates an aerosol mist of liquid particles. Example : - Spray from deodorant, paints etc.
Timeline Of Aerosol Technology 1929: Invented by Norwegian chemical engineer, Erik Rotheim
1942: Aerosol spray can of insect repellent developed
1947: Aerosol technology introduced in air conditioners, refrigerators and spray cans
1974: Discovered that CFCs deplete ozone layer
1978: Use of CFC propellant banned
1987: The Montreal Protocol signed by 24 countries
1996: CFC propellant production in industrial countries was fully phased out
2005: The ODC methyl bromide phased out
2020: Expect phase out of ODC HCFCs under The Montreal Protocol
Working Principle of Aerosol Can
Components of Aerosol Can Can The Head Space Fluid The Curved Base Valve
1. Can
The pressure inside an aerosol can is 2-8 times higher than that of the atmospheric pressure. So Can is to be very strong to withstand the pressure difference between inside and outside it.
Manufacturing of Can Usually made from thin sheet of steel Coating of another material is done on steel to stop rusting
or reacting with product or the propellant. Usually the coating is Tin, often applied by electroplating,
which turns steel into a metal called Tinplate. Tinplate is wrapped into cylinder that has a top and a bottom
to ensure can is completely leak-proof. Tinplate is also replaced by aluminium can which is made
through a Die so as to make single piece can. Product labelling and printing is done by Offset printing
process. Some aerosol cans are also made from plastic polymers and
glass.
TYPES OF AEROSOL CAN
I. Three Piece Tinplate Aerosol Can
II. Two Piece Aerosol Can
III. Single Piece Aerosol Can
THREE PIECE TINPLATE AEROSOL CAN Most widely used Made by seaming together
three components. The body cylinder which is
welded from pre-printed plate
The cone and dome are made by tinplate are flanged by double seam operation
TWO PIECE AEROSOL CAN Cone and body is
a single piece made from aluminium
Dome is made up of tinplate and is double seamed
SINGLE PIECE AEROSOL CAN Also termed as Monoblocks as made
entirely in one piece from aluminium
2. The Head Space
When the can is filled, there is space left at the top to allow for some of the propellant to remain as gas.
3. Fluid
An aerosol can contains two fluids, one which boils well below room temperature (called the propellant) and the other which boils at much higher temperature (called the product).
The Product
It is the substance which we actually use. It is also called the active ingredient which is
dissolved in propellant using other inert ingredients.
Once sealed inside the can, the product is safe from evaporation and contamination.
The Propellant
It is means of getting the product out of the can.
It is the driving force behind the aerosol can.
There are two types of propellants: Liquefied Propellant Compressed Gas Propellant
Representation of Propellants inside Can
Formulation of Product & Propellant
Sr. No. Product Ratio(Product : Propellant)
1 Space Sprays 20:80
2 Surface Sprays 75:25
3 Shaving Foams 95:05
4 Hair Sprays 70:30
Typical Propellants Being Used Liquefied Petroleum Gas: - These are flammable
and used in most aerosols today including household products.
Di-Methyl Ether: - It is an alternative to LPG and is more commonly used in personal care products and air fresheners.
Chlorofluorocarbons: - CFCs were used very commonly but after the discovery that they depletes ozone layer, their use has been banned. But they are still used in inhalation aerosols, as
used in treatment of asthma.
Non-Soluble Compressed Gas: - They are used in consumer products as an environmental alternative to LPG. Example is nitrogen.
Soluble Compressed Gas: - It is also an alternative to LPG but have very limited use mainly with alcoholic system such as air treatment products, deodorants and personal care products.
4. The Curved Base
The unusual curved bottom of aerosol container performs two functions: -
Strength of Can
Ease of Complete Consumption of Product
5. Valve It is a complex little thing fitted at the top of the
can. It is attached to the dip tube. It can work in two ways, one is when actuator is
pressed to open the valve and other is valve is pushed to the side in case of foam.
Components of Valve
Method of Filling Aerosol ContainerThis process involves four operations: - Product FillingRemoval of Air From Head SpaceBy evacuating air from head spacePurging (Addition of few drops of propellant)Sparging (Blowing of inert gas from product)
SwagingPropellant FillingLiquefied Gas PropellantPressure FillingUnder Cup Filling
Compressed Gas Propellant
Shake Well Before Use
Few aerosol products need to be shaken well before they can be use. This is to make sure that the product and propellant are well mixed. Many propellants aren’t miscible in product and makes two different layers of liquid. Without a good shake, there will be just a pool of propellant when the product runs out.
Advantages of Aerosol Containers Long shelf life of product Odour is preserved No contamination of product from bacteria or dust Contents do not evaporate Can dispense variety of products like gels,
powder, foams, gases, liquids etc. Cans are strong and safe Convenience to use Provides even coatings of paints Product can be sprayed at large distance
Disadvantages of Aerosol Containers
Use of CFCs Losses efficiency when compressed gas
propellant is used Complex design High manufacturing cost Highly flammable
Applications of Aerosol Cans Asthma inhalers Cleaning products Insect repellents Food products Deodorizers Disinfectants Paints Fire extinguishers Hair spray Shaving foam Room fresheners Rust lickers etc.
Latest Developments
In Relation to the New Formulation Incorporation of water to limit flammability of pack due to
butane propellant In India, pilot scale plants have been developed to
produce deodorized LPG
In Relation to the New Products Edible creams Antistatic sprays for cloths and carpets Fire extinguishers