Patent GB-693051-A (GB)
Title: Improvements in or relating to resinous compositions and to laminated products utilizing the same
IPC: C08L61/26
Filed: 1950-12-07
Abstract: A synthetic resin composition comprises (1) a resin obtained from a 4,6-di-primary-amino-triazine and an aldehyde, and (2) from about 10-40 per cent based on the total weight of (1) and (2) of a polyvinyl plasticizer having a hydroxyl content of from about 3.5-25 per cent and selected from polyvinyl acetals and partially hydrolysed polyvinyl acetates.  The resin (1) is made by heating the 4,6-di-primary amino-triazine and the aldehyde in a molar ratio of 1 : 1 to 1 : 4 at pH 4-11 and at 60-200 DEG  C. till a condensation product is formed, a 50 per cent solution of which in ethyl alcohol is stable at 20-25 DEG  C.  Catalysts for the reaction are sodium, potassium or ammonium hydroxide; sodium carbonate; sodium or potassium bicarbonate; diethylaminoethanol or triethanolamine. Specified 4 : 6 diaminotriazines are n-butyroguanamine; isobutyroguanamine; n-valeroguanamine; caproguanamine; heptoguanamine; D 3 - tetrahydrobenzo - guanamine; 3 - methyl - D 3 - tetrahydrobenzoguanamine; 3 - methyl - hexahydrobenzoguanamine; 3,4 - dimethyl - D 3 - 1,2,5,6 - tetrahydrobenzoguanamine; 3,4 - dimethylhexahydrobenzoguanamine; phenylacetoguanamine; benzoguanamine; o-, m-, or p-xyloguanamines; alpha- or betanaphthoguanamines; 2-phenoxy - 4,6 - diamino - 1,3,5 - triazine; N - butylmelamine; N - phenylmelamine; N - cyclohexylmelamine; N,N - diallymelamine; and N,N-dibenzylmelamine.  Mixture of the above with melamine, dicyandiamide, thiourea, guanylurea or guanidine may be used. Specified aldehydes are formaldehyde, paraformaldehyde, acetaldehyde, trioxane, paraldehyde and benzaldehyde.  Specified polyvinyl acetals are the formal, the acetal and the butyral. Dyes, pigments and fillers may be included in the composition, e.g. ochre, carbon black, malachite green, prussian blue, ultramarine, zinc oxide, ferric oxide, zinc sulphide, titanium dioxide, cellulosic or glass or asbestos fibres and pearlescent or fluorescent material. The compositions may be formulated in the absence of a solvent, in presence of water, in presence of an organic solvent such as alcohols, e.g. ethanol; ketones, e.g. methyl ethyl ketone; esters, e.g. ethyl acetate or hydrocarbons, or in presence of an emulsifying agent, e.g. the sodium salt of carboxy - methyl - cellulose. Specified curing agents for the composition are benzoic, salicylic, phthalic and hydrochloric acids.  In examples, "Resins A-E" are made by condensing in presence of caustic soda, formaldehyde and (A) benzoguanamine, (B) benzoguanamine, (C) N,N-diallymelamine, (D) phenylacetoguanamine, (E) toluguanamine.  In examples: (1) resin "A", polyvinyl butyral and phthalic anhydride are dissolved in benzene-denatured alcohol; (2) resin "A" is dissolved in a mixture of ethyl lactate and methyl isobutyl ketone, polyvinyl butyral and benzoic acid added, the resin dried, dissolved in water and the di-2-ethylhexyl ester of sodium sulpho-succinate added; (3) resin "A", polyvinyl butyral and benzoic acid are dissolved in a mixture of n-butanol and xylene and titanium dioxide added; (4) a mixture of resin "B," polyvinyl butyral, water and phthalic anhydride is prepared; (5) a mixture of resin "C," polyvinyl butyral and phthalic anhydride is dissolved in benzene-denatured alcohol; (6) resin "O", hydrolysed polyvinyl acetate and phthalic anhydride are dissolved in benzene-denatured alcohol; (7) resin "E," polyvinyl butyral and phthalic anhydride are dissolved in benzene-denatured alcohol.  The compositions of examples (1)-(6) are coated on to paper impregnated with a melamine-formaldehyde resin and the sheets used as outside plies for a core of 12 plies of phenolic laminating stock (see Group VIII).