Document ByjOo9vQ721GEYbq2Bj44an7j

ISER CEAcNT & GYPSUM COkPORATION INTER-OFFICE MEMORANDUM date October 31, 1975 copies TO I r-Mr-Wartsufi FROM G. B. SUBJECT ACCESSORIES STATUS REPORT (W/0 696-314) DUAL PURPOSE PREMIX' Job complaints about hard to mix, gummy, jell-like, inconsistent Dual Purpose Premix are being corrected by two changes: 1. Formula change adding a second thickener. This change has been successfully field tested and new operating bulletin issued. 2. Manufacturing procedure change: Batch is started by adding water and liquid raw materials to the mixer, add the dry materials, and mix for ten minutes. The change is to let the wet mix soak for five minutes. Then . add 2 to 3 gallons water to get the mixing going again. During the next few minutes the mix will become a workable and creamy paste. Check Vicat and add water if necessary until desired Vicat spec, reading is obtained at the mixer. Then pump the paste over for packaging. The five minute soak does not delay the batch production schedule. The soak time does wetout the mix and minimizes the thickeningup problem. It is still necessary for the contractor to mix the dual purpose product on the job prior to adding water. Shadowing complaints of K-Spray ceiling texture over Dual Purpose Premix are being investigated in the E&D lab, Antioch using the water absorption test method. Formula changes tried to date have not improved the water resistance of the Dual Purpose. We have several more changes under test with results due early next month. rom* no Accessories Status Report October 31, 1975 Page 2 TOPPING PREMIX No change needed inr manufacturing procedure needed for Topping. Shadowing complaints of K-Spray ceiling texture over Topping using the water absorption test - show that a formula change is needed for the Topping. Good water resistance obtained by deleting Nopco NXZ and increasing Min-U-Gel from 10 to 25 pounds/batch. The additional 'Min-U-Gel is expected to provide storage life stability in place of Nopco NXZ. . This change will be made in a production batch and field tested during early-November. K-SPRAY CEILING TEXTURE No change in K-Spray formula is recommended at this time since we expect to correct the shadowing problem by changes in formula of Dual Purpose and Topping. COVER-TEX . Grit complaint on painted walls in San Diego still being investigated. Tests are being run in E&D lab, Antioch on retained Cover-Tex samples from Santa Ana. Part of the gypsum board sample from the job; Cover-Tex, and job paint are also being examined by Isaac Awabdy, St. Helens Paint Chemist. THREE PURPOSE COMPOUND, JFT-, ANTIOCH Formulation of a non-asbestos Three Purpose Compound using attagel clay has been unsuccessful. While attagel clay is helpful in non asbestos premix products, attagel clay does not provide adequate "body" and shrinkage control in the dry powder product. We will now try replacing asbestos fiber with Crown Zellerbach's relatively new SWP fiber. Synthetic wood pulp is made from polyethylene in Japan and imported as wet lap. Price about 60/lb. Sheets of SWP wet lap are fed through a hammer mill to fluff the fiber. We will have to determine if the fluffed fiber requires drying prior to batch mixing in the Three Purpose Compound. . GBK/lz