Document QMqKzmKoLZ3GVQkELbyqwyoEo

APPENDIX IV F.J. STOKES CORPORATION 8800 TABOR ROAD, PHILADELPHIA 20, PENNSYLVANIA CUMBERLAND 8*010.0 October 18, l?6l Mr, A. M. Auster Technical Section E. 1, duPont- deNemours Company, Incorporated Pigments Department Newport, Delaware Dear Mr. Auster: Thank you for your letter of October U, 1961, in which you included a copy of the drying questionnaire for the second material -which we discussed in my recent visit to your plant. The information on the first product which we discussed has been conveyed to our Laboratory personnel prior to this time, and they have shown a reluctance to run your product in the laboratory. 2h reviewing this with Mr. William Hamilton, director of our laboratory, we find that in the past when running dyes, we have had the difficulty of cleaning up after the test for an extensive period of time while not being fully able to remove the dye from our process lines. Under the circumstances, all subsequent tests show traces of the dye material which was run in the equipment. in reviewing 'this with Mr. Hamilton, I assured him that this was a dye, the type of which could be readily desolved with moisture for removal from the equipment. This, however, was not sufficient for him, and under the circumstances, he does not feel that he can jeopardize our equipment and eventual future customer tests by having dye stuffs processed: in the rotating and rotary vacuum dryers. Since, you have no doubt come across this problem before, we are wondering what your feelings are on the aspects of complete clean up and. removal of your product from the dryers. Please do not consider this letter a firm indication that we will not test this material, since perhaps you have information which would alleviate Mr. Hamilton's fears. 3h any event, I will plan to contact you again very Shortly to again review this with you. WJL/gin Very truly yours, F. J. STOKES CORPORATION <7 f 1 if William J, Leighton District Sales Engineer Vacuum Division r ) N39940