Colour Scene Investigation Colour Communication

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Colour Communication in Fashion and Textile Design

Describing colour is extremely difficult, if you have ever tried to accurately describe a colour to someone then you will know just how tricky it is!

Clear and accurate colour communication is essential within the colour using industry so we need an effective way of describing colours. Most systems agree on three attributes of colour, but the names for these attributes vary from one industry to the next. The most recognised method for describing colour is the Munsell system which uses the terms hue, value and chroma.

This workshop is tailored to make you think about your designs in the context of how to promote colour constancy in a chosen product.

Context of the Investigation Communicating colour with accuracy and precision to facilitate colour constancy in product production on a global scale.

Objectives ✓ Understand the meaning of the terms of hue, value and chroma and their use in colour

communication. ✓ Identify fibre types, their properties and the consequent dyes / dyeing processes required. ✓ Evaluate how colour constancy affects environmental impact of your product in

production and end use.

Skills

✓ Communication ✓ Rationalisation ✓ Decision making ✓ Evaluation

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The Task: ✓ Watch the videos and answer the appropriate sets

of questions on the following pages. ✓ Identify the 3 types of fabric you have been

given. ✓ Key words beyond hue, value and chroma are

available for students who wish to challenge themselves in the understanding of vocabulary used in colour communication.

Resources 1. Workbook. 2. On-line materials. 3. Fibre samples – nylon, polyester and

cotton.

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Key words

• Chroma: The saturation or brightness of a colour. Chroma can also describe a hue’s or colour’s strength

• Hue: The identification or name of a colour • Value: The lightness or darkness of a colour • Additive colour: The process of mixing the colours of light together • Subtractive colour: The process of mixing dyes or pigments together • Cones: Cells in the retina that are sensitive to bright light and colour • Colour deficiency: The inability to distinguish one or more of the three colours red, green

and blue • Metameric pair: Two colours that match under the same light source as viewed by the

same observer • Metamerism: Occurs when two or more similar hues appear to match under one light

source but then mismatch under another. • Incandescent light: A type of artificial light that bathes the area in a yellowish glow. It is

often referred to as “warm light” • Spectrophotometer: A tool for measuring colour. The spectrophotometer measures and

determines each wavelength of light absorbed by a coloured sample • Wavelength: A measure of light. The distance between crests in a wave of energy • Colour Constancy: Colour constancy is the perception that an individual object’s colour is

constant and unchanging regardless of changes in the lighting conditions. • Colour Vision: The way a person views colour and is unique to every individual.

Metamerism in more detail: Metamerism occurs when two or more similar colours appear to match under one light source but then mismatch under another light source. For example, colours may look the same in natural daylight and then look different under fluorescent light or other forms of artificial light. The colourist can check samples for metamerism by viewing the samples in a light cabinet. The light cabinet is a viewing box containing different light sources, such as daylight (D65), incandescent light (tungsten filament) and fluorescent light.

The common lightbulb is referred to as an incandescent light source and it produces a warm light (red to yellow range of the spectrum) and so incandescent light intensifies warm hues. Fluorescent light tubes produce a light that is predominately blue-violet and so works well rendering cool hues.

Sunlight is constantly changing and so will change the appearance whether colour is viewed at dawn, midday or dusk. Furthermore, colours appear different when viewed at the equator or at the north pole and, finally, the distance between two closely matched colour samples can create the illusion of them appearing the same or different.

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1.0 Colour Communication: Video Questions.

1. What is the most recognised system for describing colour?

2. What are the 3 terms that this system uses to communicate colour?

3. Describe the meaning of ‘hue’.

4. Describe the meaning of ‘value’.

5. Describe the meaning of ‘chroma’.

6. Name 2 other systems which are used to communicate colour.

7. What is the RGB colour system used for and what are the primary colours?

8. What is the CMYK colour system used for and what are the primary colours?

9. Name the graphical image used to give us a visual illustration of a colour.

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2.0 Sustainability: Video Questions.

1. Name 3 types of sustainability?

2. Give 4 key factors involved in environmental sustainability in the textile industry.

3. What is meant by social sustainability?

4. What is meant by financial sustainability?

5. In groups, discuss ways in which you might reduce the environmental impact of the textile

industry.

Note your shared ideas below.

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3.0 Cotton Fibres and Reactive Dyes: Video Questions.

1. From which part of the plant is cotton obtained?

2. What does the process of ‘scouring’ remove from the seed?

3. What type of dyes does scouring allow to be used on cotton?

4. What type of fibres make up cotton?

5. What are the basic building blocks of cellulose?

6. Give 3 other examples of natural plant based fibres.

7. What types of dyes can be used for cotton?

8. What types of bonds form between reactive dyes and cotton?

9. Are these bonds strong or weak and what does this mean in terms of wet fastness?

10. What are the main advantages of using reactive dyes on cotton?

11. What is the main disadvantage of using reactive dyes on cotton.

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4.0 Polyester Fibres and Disperse Dyes: Video Questions.

1. What is polyester derived from?

2. Polyester is hydrophobic: what does this mean?

3. What type of dyes are used for polyester fibres?

4. Give 2 examples of polyester fibres in terms of their physical characteristics?

5. State one use for each of the different fibres in your answer to question 4?

6. In what form are disperse dyes added to polyester fibres.

7. Why is an extremely high temperature of up to 130oC required for this process?

8. What types of bonds are formed between disperse dye and polyester fibre molecules and

are these bonds weak or strong?

9. Why do disperse dyes give good wash fastness when applied to polyester?

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5.0 Nylon and Acid Dyes: Video Questions.

1. What is nylon derived from?

2. Name the process used to extrude nylon.

3. What type of dyes are used for nylon fibres?

4. Give 2 examples of nylon fibres?

5. Give 2 different properties of the fibres named in Question 4?

6. Name a fibre other than nylon on which acid dyes are used.

7. Which chemical group on nylon fibres attracts the negatively charged (anionic) acid dyes?

8. Name the type of bond formed between acid dyes and fibres?

9. Are these bonds weak or strong and what does this mean in terms of wet fastness?

10. Give 4 examples of acid dyes.

11. Levelling acid dyes consist of small molecules. Give one advantage and one disadvantage of

this characteristic.

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Properties and Uses of Fibres.

1. Look for fibres within the room you are working or from your personal belongings.

2. Write down as many properties of these as you can, using your prior knowledge and that gained from this course so far.

3. Identify similarities and differences between them such as elasticity, strength and handle.

4. Use these properties to evaluate why each one would have been the fibre of choice for the product considered.

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Summary.

The most recognised system for describing colour is the _______________ ______________ which

uses the terms:

1. Hue – meaning ______________________________________________________________

2. – meaning __________________________________________________________

and

3. – meaning ___________________________________________________________

The 2 primary colour systems are __________, which is used for ______________ ___________ and

__________, which is used for _____________ ___________.

In the Textile Industry, 3 types of sustainability are considered; these are:

1. S _________________________

2. F _________________________

3. E _________________________

From your post-video discussions on the subject, write down what, in your view, are the 2 most

important ways of minimising the environmental impact of the Textile Industry for the future.

1. ___________________________________________________________________________

___________________________________________________________________________

2. ___________________________________________________________________________

___________________________________________________________________________

Cotton is obtained from the _______ of __________ ___________. Cotton consists of ____________

fibres, the basic building blocks of which are ____________ molecules. The seed must be _________

before processing to remove the _______ ___________ in order that ______ __________ dyes may

be used. ______________ dyes are most commonly used on cotton because they are ____________

which means ‘________ ____________’. Strong ______________ bonds are formed between the

dye and the fibre giving good ________ fastness.

Polyester is derived from _________ ______. It is __________________ in nature which means

‘_______ __________’. ____________ dyes are used to colour polyester and are applied in the form

of __ _______ ______________ at up to ________oC. ______________ bonds and V___ ____

W______ forces link disperse dyes to polyester fibres. These bonds are weak but still allow good

______ fastness because they ________ ________.

Nylon is a synthetic fibre extruded, like polyester, by a process called _________. It is coloured using

mainly ________ dyes. Two examples are Nylon 6 and Nylon 6,6; example properties of these are:

__________________________________________________________________________________

__________________________________________________________________________________

Nylon molecules are rich in amino (NH+) groups and, therefore, attract acid dyes which are

______________ charged or ______________. The type of bonds formed here are _____________.

In general, this produces good _______ fastness but this is capability is _______________ in lower

molecular weight acid dyes.

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To conclude: This short course has provided an insight into the complexity of describing colour and the 3-

dimentional nature of this process. There are a number of reasons why colour communication is

difficult, for example:

1. Perceptions and interpretations of colour are very subjective.

2. Physiological and psychological factors can influence colour perception.

3. Perception is altered depending on surroundings, particularly lighting conditions and

adjacent colours.

A set of international standards is therefore required in order to ensure colour constancy in any

given product anywhere in the World. This is achieved by use of the Munsell System (originating in

1905) which sets numerical values to the terms hue, value and chroma and is utilised in the

Archroma Color Atlas on-line which offers dedicated colour pages with ‘dyeing recipes, technical

support, and visual representation of similar colours’ to that chosen for a particular product or

design.

During the course you have looked at 3 different fibres and the dyeing process of choice for each.

Colour constancy of a product relies on using the correct fibre / dye combination and the optimum

shade referenced from the Color Atlas. This will not only give you a better quality-controlled

product, but it will reduce the negative environmental impacts, both in production and end use, as

summarised in the following diagram:

End user satisfaction

Repurchase of the same and / or associated

products of the same shade

Greater efficiency in production -

more reproduction of quality products

Less waste through

production

Less waste from end-user

Colour Constancy

Lower negative environmental impact!

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Table 1. Revisiting the Learning Objectives and Skills.

Use a scale from 1 -3 to indicate the extent to which you feel you have achieved the learning objectives where 1 is the highest.

Learning Objective Achieved 1 2 3

Skill Acquired Used Developed

Distinguish and compare colours using the terms ‘hue’, ‘value’, and ‘chroma’.

Identify fibre types, their properties and the consequent dyes / dyeing processes required.

Evaluate any relationship you can deduce between colour constancy and environmental impact of your product in production and end use.

Communication Rationalisation Decision making Evaluation

Table 2. Structured Reflection.

Date Description of event What did I learn?

Short term implications

Long term implications

Feedback from other students

What will I do differently?

Notes / targets

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