Document 2Ryadm7Yv4goOKJvYOVjwx3oa

FROMlMT. S. T. Bowell ) CITY* Strongsville, DPJRC SUBJECT* LEAD REMOVAL GLIDDEN-DURKEE Jan. 4# 1973 FOR* Mr. G. L Bechtel - UCB CC* Mr. E. B Buchner Mr. W. M Tome Mr. J. E Southwlck Dr. H. J Kiefer - UCB Here is a table giving esoentially the dry times involved for Endurance House Paints at a very lovf level of cobalt plus zirconium drier and at the recommended level of cobalt and zirconium. It is compared to our present lead-containing drier system and to Sherwin-Williams' current dry capability. 50 70* Sherwin-Williams 36 Hours (7) 18 Hours .01 Cobalt 26-30 Hours 20-22 Hours .03 Cobalt (recommendation) 19-20 Hours 17 (7) Hours present .5 maximum Lead Just barely overnight Normal (16 Hours) You will see that our present lead-containing drier system gives satisfactory overnight dry at 70 and just barely satisfactory dry at 50. Our recommended level of cobalt and sirconium for paint to be sold in Chicago is slightly slower, and at lower temperatures can give problems with regards to overnight recoat ing. With cobalt at the 0.0i?6 level the dry would be extended even at 70 to such an extent that a person would not receive sufficient dry overnight to render a satisfactory film and to permit recoating. The dry of an oil house paint is something that proceeds slowly, and can be rated only with difficulty at 'standard'* points (out of dust, tack-free, dry-to-touch, etc.). The nature of the dry with cobalt-zirconium is different than that with lead, and direct comparisons cannot be made. The figures given are not to be taken as accurate to the nearest hour, but are the best statements we can make of the relative drying times of these systems. STB/ab S. T. Bowell GLD007126