Color Comparator

Titanates trigger peroxide-initiated curing of unsaturated polyesters to give products of superior color, compared to conventional cobalt-initiated... 

Color. Color is deterrnined through the use of a Nessler-type visual color comparator as described in ASTM Designation D1209. 

Colorimeter Also called color comparator or photoelectric color comparator. An instrument for matching colors with results about the same as those of visual inspection, but more consistent. Basically the sample is illuminated by light from the three primary color filters and scanned by an electronic detecting system. It is sometimes used in conjunction with a spectrophotometer, which is used for close control of color in production. 

Referring back to our Color Comparator of 7.8.19., we use these concepts to calibrate our lamps in terms of spectra and relative energy in terms of these standard sources. EUununant - B, by the way, was originally defined as... 

Nonetheless, while determining color by the color- comparator mode was a distinct improvement over prior methods of color comparison, the method was... 

Azo dyes are one of the most important types of dyes that are extensively used in textile, leather, food, cosmetics, and paper product industries due to a more economical synthesis, firmness, and greater variety of color compared to natural... 

The United States production of amino plastics was more than 3 billion pounds in 2001. The urea-formadehyde polymers account for slightly more than 85% of the total. The amino plastics are similar in properties to the phenolics but are clearer and colorless. They are also harder but have somewhat lower impact strength and resistance to heat and moisture. The melamine resins are better than the ureas in hardness and resistance to heat and moisture. The melamine and urea resins are rated for continuous use at temperatures of 130-150°C and 100°C, respectively. The general applications of the amino and phenolic plastics are the same but there are uses where the amino plastics are superior. The melamine resins find an important niche due to their combination of clarity and lack of color compared to the phenolics and their superior hardness and heat and moisture resistance compared to... 

Color Compare the color with soln prepd by adding 0.5ml of 0.1N iodine soln to 100ml distd w... 

The ratio of jy -epoxide (shown above) to anti-epoxide is 10—25 1 with TYZORTPT catalysis, whereas vanadylacetylacetonate is less selective and / -chloroperoxybenzoic acid gives the reverse 1 25 ratio. It is supposed that TYZOR TPT esterifies the free hydroxyl, then coordinates with the peroxide to favor syn-epoxidation (135). This procedure is related to that for enantioselective epoxidation of other allylic alcohols in 9—95% enantiomeric excess (135). Titanates trigger peroxide-initiated curing of unsaturated polyesters to give products of superior color, compared to conventional cobalt-initiated... 

Color of the uncured epoxy resins is an indication of contamination, incomplete polymerization, oxidation, and other factors. Aromatic resins with lower molecular weight generally have better (lower) color. Color is usually reported in terms of the Gardner liquid color standards or the Hellige color comparator or by means of the APHA number. 

Asphalt (Natural) A natural mineral pitch, tar or bitumen composed principally of hydrocarbons a natural bituminous rock that is dark colored, comparatively hard and nonvolatile. Does not include asphalt, bitumen, tar or other substances, derived from petroleum processing. 

These oils are characterized structurally by a large number of paraffinic side chains (55% min. Cp), and thus are highly saturated. They excel in initial color. Compared to naphthenic and aromatic oils they are most resistant to oxidation and color degradation by ultraviolet light. Their resistance to oxidation increases as their molecular weight increases. SONPAR oils are de-waxed to low pour points, and their volatility is quite low compared to the naphthenics and aromatics, as indicated by their higher flash points. 

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