Patent GB-921071-A (GB)
Title: Subbing layer for hydrophobic, dimensionally stable, inert-surfaced filmbase
Inventor: WINCHELL ALAN M
IPC: C08L63/02
Filed: 1961-05-11
Abstract: A solution for subbing a hydrophobic inert-surfaced film base, e.g. polyester, polycarbonate or polystyrene film, comprises an aqueous-organic solvent solution containing gelatin, an alkylene carbonate containing 2 to 4 carbon atoms in the alkylene group, cellulose nitrate, and an epoxy resin as its essential components. The alkylene carbonate, e.g. ethylene or propylene carbonate, may be present in an amount ranging from 8 to 25% by volume of the solution. The epoxy resin is prepared by the reaction of bisphenol A with epichlorohydrin and may have a melting point as high as 155 DEG C. The resin, which may be present from 0,2 to 0,4 gram per 100 c.c. of solution, may be cured, after the subbing of the film base, by allowing the resin to stand, by heating to a temperature of about 100 DEG C., or preferably by the use of curing agents which may be present from 0,004 to 0,006 gram per 100 c.c. of solution.  Curing agents specified are organic amines, e.g. diethylaminopropylamine, 3-dimethylaminopropylamine, isopropylaminopropylamine, 3,31-iminobis(propylamine), ethylene diamine, diethylene triamine, the complex of boron trifluoride with monoethylamine, and peroxides, e.g. benzoyl peroxide or t-butyl peroxide.  The cellulose nitrate may be present in about the same quantities as the epoxy resin.  Gelatin may be present from 1 to 0,5 gram per 100 c.c. of solution.  A small amount, i.e. 0,003 to 0,0075 gram per 100 c.c. of solution, of glyoxal dissolved in an aqueous-organic solvent, e.g. a water-methanol mixture, may be added to the solution. Dispersing agents, e.g. phthalic, acetic or salicylic acid, may be present in an amount of 0,5 to 0,2 gram per 100 c.c. of solution.  Specified organic solvents are diacetone alcohol, propylene dichloride, mesityl oxide, methanol and glacial acetic acid.  The quantity or organic solvent may vary from 8 to 65% by volume of the solution.  The solution may be prepared by adding a solution containing gelatin, after warming, to a solution of the alkylene carbonate and the curing agent for the epoxy resin, and thereafter adding a solution of the cellulose nitrate and epoxy resin.ALSO:A solution for subbing a hydrophobic inertsurfaced film base e.g. polyester, polycarbonate or polystyrene film, comprises an aqueousorganic solvent solution having gelatin, an alkylene carbonate containing 2 to 4 carbon atoms in the alkylene group e.g. ethylene or propylene carbonate, cellulose nitrate, and an epoxy resin as its essential components.  Gelatin may be present from 1 to 0.5 gram per 100 cc. of solution.  The cellulose nitrate may be present in about the same quantities as the epoxy resin, i.e. from 0.2 to 0.4 gram per 100 cc. of solution.  The solution may also contain glyoxal, dispersing agents, and curing agents for the epoxy resin.  The solution may be prepared by adding a solution containing the gelatin, after warming, to a solution of the alkylene carbonate and the curing agent for the epoxy resin, and thereafter adding a solution of the cellulose nitrate and epoxy resin.  Specified organic solvents are diacetone alcohol, propylene dichloride, mesityl oxide, methanol or glacial acetic acid.