• It is essential to remember that color is subjective.
• It is not possible to eliminate the subjectivity with spectrophotometer.
• The subjective parameters:
• The light source
• The part finish
• The observer
• The type of polymer
• The configuration of the part
• The non-subjective parameters:
• The base resin
• The opacity

For example: if you tried to use the same color concentrate for a homopolymer polypropylene and co-polymer polypropylene, you are not likely to achieve the same color.

COLOR PROBLEMS
EASY TO OVERLOOK VARIABLES:

• Part gloss: The more gloss the darker the color will appear
• Reference Standards (masters) Do we all have the same standard? How are they stored? They should be kept in a dark places, as color will fade with time.
• Have you changed your base resin?
• Melt temperature: Is the mold in a different machine than previously used? Different screw geometry will produce a different heat profile.

COLOR IS WHAT WE SEE, NOT WHAT WE MEASURE!

WHERE DO WE BEGIN?
One must supply all the necessary information and materials in order to successfully match your color and processing requirements.

• The specific type, grade and manufacturer of the plastic to be used.
• A good standard (e.g. existing color concentrate vs. a leaf).
• Your manufacturing process: (e.g. Injection blow molding, hot runner mold, temperature inside your barrel).
• The end product: (Indoor/outdoor use, FDA, light exposure, bottles etc...).
• Your budget.

WHY IS ALL THIS INFORMATION NECESSARY?

• Every pigment and dye will have different heat parameters, light fastness, price tag and ability to make your manufacturing process and end product a great success.
• On the other hand not enough information can make color the "necessary evil".
• Always provide as much information as possible.
• It is our aim to incorporate the correct processing and additive aids to simplify your manufacturing needs.

WHY ISN'T MY COLOR MATCH EXACT?
It all starts at the beginning of a new project. "The Design Stage"

The initial match may have been a pantone number (paper), a painted part, fabric or a different grade of plastic than you are using. When there is a problem, the solution is to COMMUNICATE. We must all work together to understand and resolve the issue.

There are three major classes of problems:

• Cosmetic
• Mechanical
• Dimensional

COSMETIC PROBLEMS
Metamerism when a color looks different under different light sources.
When we match the color using two different types of resin, we experience metamerism as well. It is not possible to do an exact match (e.g. A GPPS standard to a TPE part.) These have different textures making is impossible to achieve a 100% perfect match.

WHY DOES THIS HAPPEN?
When light hits the surface of the part, the angle of refraction is different for each family of plastic. Consequently, the human eye will see the difference.

MECHANICAL PROBLEMS

• It is not possible to avoid the reduction of mechanical properties of a colored part to a part molded with natural resin.
• Color is a contaminant and will reduce the mechanical properties differently.
• The resolution of most color problems is dependent on communication with everyone involved.

DIMENSIONAL PROBLEMS

• Some colors will nucleate and the cycle time can be shortened.
• Some colors will require different heating band setting profiles due to heat sensitive pigments. This is normal.
• Some color will cause shrinkage. warpage, plate-out and blanching. This will require a rematch in order to reformulate by using pigments and additives to prevent these problems.

IT IS OUR JOB TO PREVENT PROBLEMS. YOU CAN RELY ON FERCO COLOR AS YOUR DEPENDABLE SOURCE FOR COLOR AND COMPOUNDING.

UNDERSTANDING PIGMENTS AND DYES
Pigments: A pigment is a colorant, insoluble in the medium in which it is used. A pigment is classified in two types: Organic and Inorganic. Most pigments will give you opaque color. Pigments range in thermal stability, heat stability, FDA, heavy metal free and those containing heavy metal. Ferco Color always matches with heavy metal free pigments unless otherwise specified by our customer.

Dyes: Heat stable and light stable. Generally used for transparent applications. They are heavy metal free.
Dyes are limited in use. They cannot be used in TPE's, TPU's, Polyolefin's, or plasticized PVC's, as they will leach. There are very few dyes available that are FDA or non-leaching.

HOW DO WE MAKE COLOR?
Dry Color: A composition of pigments and/or dyes and additives blended in a ten-liter high intensity mixer for optimum dispersion success. This is the most cost effective method of coloring plastic, however also the messiest

Color Concentrate: A dry color blended with the required carrier system for use in your plastic and necessary additives to aid your processing. These materials are blended in a high intensity mixer, and then extruded on extruders varying from 2.5" to 6". This is considered the most practical means of coloring plastic in terms of cost and efficiency.

Liquid Color: A dispersion of pigments or dyes blended with specialized liquid vehicles. Liquid Colorants can be extremely clean when used properly and facilitate fast color changes between production runs resulting in excellent productivity and efficiency for the manufacturer. The liquid vehicle is usually compatible with all polyolefin, styrenic and engineering resin systems. High letdown ratios arc achieved by loading up to 75% pigment (by weight) in the liquid vehicle resulting in significant cost savings.

Precolor: A dry color is added to your base resin blended and extruded. This eliminates operator error, dispersion problems and ensures color consistency. This is the most expensive route of coloring your plastic.