H O W G.E.'S RECORDING SPECTROPHOTOMETER HELPS YOU
Make Color Formulations at Lowest Cost HERE'S HOW
PROBLEM 1 You are bidding on a job which requires you to match the color of a customer's sample. In order to get the job, you must give the customer an acceptable match (light, fast, etc.) at the lowest possible cost.
Analyze the sample with the General Electric Recording Spectrophotometer using the color matching " R " (reflect ance) cam. The resultant curve (black dot-dash line) is the "shape" of the sample in question. Segments of this curve tell us that the color is composed of two color ants (red line and dash line). These two colorants can be positively identified since each colorant has a characteristic "optical fingerprint" which can be identified by checking reference transmission curves of colorants available to you. This check may reveal several other color curves which closely approximate the exact color ants which you want to replace with a less expensive one. For example, the red line represents a transmission measurement of one of the colorants used to make the customer's
POSSIBLE SUBSTITUTES
sample. Below, the log density (log log10 (1/T) curve of this same colorant is shown with black curves which are near matches. A simple plastic scale can be used over any colorant curve to show price of the colorant at the concentration needed to match your color. Therefore, you can compare the near matches on the basis of nearness and of cost. Doing this for each colorant in the mixture, you can then compute the least costly of the avail able combinations. It is often possible to reduce the number of colorants required to match the customer's sample to his satisfaction and to find cheaper colorants than were originally used. Manufacturers in such industries as textiles, printing inks, dyestuffs, plastics and paper substantially decrease manu facturing costs and produce products of more consistent quality with General Electric's Recording Spectrophotometer.
AND THEIR
RELATIVE COSTS
Be Sure You Don't Have a Metameric Match PROBLEM 2 A customer has submitted a sample of green material. You have mixed a formula which matches the customer's sample under daylight but which shows up as distinctly brown when placed under tungsten light. Your problem is to determine how the colorant formula can be adjusted to obtain an exact visual match under all light conditions.
bination of green and red or brown. Be sides helping you understand mismatches when they happen, familiarity with curves from the G-E Spectrophotometer helps you avoid choosing wrong colorants in any color matching problem. For information call your G-E Appa ratus Sales Office or write Dept. 585-69, General Electric, Schenectady, Ν. Υ. For news on color control ask to be added to mailing list No. 79.
HERE'S HOW Measure both samples on the General Electric Recording Spectrophotometer using the color matching " R " cam. The G-E Spectrophotometer gives you, in only 54 seconds, a curve for each sample. Com parison of these curves will show you how the color composition of the customer's sample differs from your formula. The problem stated above is solved in our graph. The customer's sample (red line) will be green under all illuminants since its curve peaks in the green and has a low red tail. Our formula (black line) peaks in green and also shows a lot of red. Daylight (predominately blue) would "dilute" the red so that our eye would see a green color. Tungsten light (predomi nately red) would emphasize the red colorant so that our eye would see a com
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