Document R2pxVGBZGR31N0nMBQmKBVM6X

GROSS REFERENCE PUNCH CARD INDEX C" / RETURN 10 MARSHALL LABUBATORT 0, R. B. MerkXe, Lab, I St. Lowell, Lais* O, F* Osborn3 Lab. R. T. Bucks , Parlin J, D. Pickens, Flint "INQPED" Marshall Laboratory October 19, 1951 MEMORANDUM REPORT NO M-395 INTRODUCTION THE IMPROVED GLOSS OF 895 LINE WHIT**p yn*.<tw _*U 1 4%"*vtli NOT FOR CIICIMHm In order to revise the 295 Lln| White, previously meeting Specification 52-L-26, to conform to Specification HIL-L-7178, it was necessary to have a minimum gloss of SO* The current paste-type dispersion for the white pigment (WX-003} is unable to consistently give this minimum gloss in the finished product It has been long established that a roll stock dispersion, though more expensive, gives a higher glo'ss than the past type In the attempt to raise the gloss and to maintain minimum cost, blends of roll stock and paste dispersions were formlatsd to pro duce the same ultimate compositions. CONCLUSION ! In the 295 line vehicle when small increments of white roll stock were added to the paste-type dispersion, the gloss was raised at a rather high rate, tending to level off as the roll stock increased. In the above problem, it was found that if 20$ of the pigment was added by roll stock dispersion, the gloss was increased from 73 to 89, although further additions of roll stock did not appreciably effect the gloss. It is evident that if this system can be applied to other vehicles and pigments, the following effects may be realized: 1, A less expensive product with no sacrifice in gloss by substituting piste dispersion for a large part of the roll stock In 100$ roll stock formulations. ; 2. An Increase in gloss in existing paste dis persions at a small increase in cost byadding a small amount of roll stock**type dispersion. EXPERIMENTAL The 295 line vehicle is composed of nitrocellulose. Duraplex ND-77-B and trieresylphosphate at a ratio of 10/18.8s3.6 Since this specification is of the composition typo,, no attempt was made to evaluate the results in any other type of vehicle N35433 2- Memorandum Report No. M-5S5 October 19,, 1951 All gloss determinations were made by the pour method, conforming to TM-920,, The composition of the finished product would be the same In all cases, making allowances for the extra cellulose nitrate and plasticizer added by the roll stock. The roll stock, now coded RX-1250, was formulated to have the maximum pigment content consistent with good rolling and gloss. The results obtained in these various compositions and gloss readings are found in the attached graph* MARSHALL LABORATORY R. A, ROBIQHABD RARsaig 10/17/51 Attach. DUP030003309  rsss<! > ".3,-iin3S DUP030003310