Patent GB-1007469-A (GB)
Title: Manufacture of coated paper
IPC: B41M5/124
Filed: 1962-07-02
Abstract: A coating on paper for printing has a microporous structure and consists essentially of non-plastic, preferably highly polymerized, organic substance deposited from solution by flocculation and precipitation as microscopic grains agglomerated to each other, but separated by intervals.  In the Examples:  (1) cellulose acetate is dissolved in acetone, toluene is added and the mixture used to coat paper; alternatively other esters or ethers of cellulose may be used, the solvent may be ethyl acetate or methyl acetate, and the non-solvent may be xylene, heavy oil, turpentine or ethyl alcohol; (2) polyvinyl acetate-chloride is dissolved in acetonel alcohol is added and the mixture used to coat paper; alterntively one may use polyvinyl chloride, polyvinyl acetal or butyral, the solvent may be tetrahydrofurane, dimethylformamide or dimethylsulphoxide, and the non-solvent may be isobutyl alcohol; (3) cyclohexarone resin is dissolved in alcohol, an aliphatic hydrocarbon is added, and the mixture used to coat paper (4) polystyrene is dissolved in benzene, alcohol is added, and the mixture used to coat paper; (5) paper is coated with an aqueous solution of gum arabic and before evaporation it is passed through a bath of alcohol to flocculate the gum; (6) polybutadiene resin is dissolved in trichlorethylene, an alcohol is added and the mixture used to coat paper; and (7) paper is coated with one of the above solutions, and a current of gas saturated with the vapour of the non-solvent is passed over it.ALSO:A coated paper for printing consists essentially of a paper base and a uniformly light-coloured, hard, thin coating film adhering thereon.  The film has a microporous structure and consists essentially of a non-plastic, preferably highly polymerized, organic substance deposited from solution by flocculation and precipitation as microscopic grains agglomerated to each other, but separated by intervals.  In the Examples: (1) cellulose acetate is dissolved in acetone, toluene is added and the mixture used to coat paper; alternatively other esters or ethers of cellulose may be used, the solvent may be ethyl acetate or methyl acetate, and the non-solvent may be xylene, heavy oil, turpentine or ethyl alcohol; (2) polyvinyl acetate-chloride is dissolved in acetone, alcohol is added and the mixture used to coat paper; alternatively one may use polyvinyl chloride, polyvinyl acetal or butyral, the solvent may be tetrahydrofurane, dimethylformamide or dimethylsulphoxide, and the non-solvent may be isobutyl alcohol; (3) cyclohexarone resin is dissolved in alcohol, an aliphatic hydrocarbon is added, and the mixture used to coat paper; (4) polystyrene is dissolved in benzene, alcohol is added, and the mixture used to coat paper; (5) paper is coated with an aqueous solution of gum arabic and before evaporation it is passed through a bath of alcohol to flocculate the gum; (6) polybutadiene resin is dissolved in trichlorethylene, an alcohol is added and the mixture used to coat paper; and (7) paper is coated with one of the above solutions, and a current of gas saturated with the vapour of the non-solvent is passed over it. Specification 868,579 is referred to.