Patent GB-978265-A (GB)
Title: Method for coating tablets
IPC: A61K9/28
Filed: 1961-05-19
Abstract: A composition suitable as a glossing agent for tablets comprises hydroxypropyl methyl cellulose containing 5-15% by weight of 2-hydroxypropoxyl groups and 27-32% by weight of methoxyl groups, and/or ethyl cellulose containing 42 to 49.5% by weight of ethoxyl groups, and a non-aqueous solvent.  Film-forming polymers other than said glossing agent and plasticizers may be also present.  Polymers specified include a carboxylated polyvinyl acetate copolymer, polyvinyl pyrrolidone, cellulose acetatephthalate, acetate-propionate, and acetate-butyrate; maleic anhydride-ethylene copolymers; carboxylated styrene copolymers; ethylene oxide copolymers; polyvinyl pyrrolidone-vinyl acetate copolymers; polyvinyl acetate copolymers; lower alkyl methacrylates; copolymers of lower alkyl acrylates with lower alkyl methacrylates; and copolymers of lower alkyl methacrylates with methacrylic acid.  A water soluble wax, e.g. polyethylene glycol may also be used.  Specified plasticizers include triethyl citrate, ethylene oxide-polypropylene glycol condensation products especially those sold under the Registered Trade Mark "Pluronic", glycerine, propylene glycol, polyethylene glycols, ethyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate, and acetyl triethyl citrate. Specified solvents include mixtures of ethanol with any of the solvents methylene chloride, chloroform, acetone, ethyl lactate, methyl salicylate and benzene.  In preferred compositions (a) ethyl cellulose and hydroxypropyl methyl cellulose are present in a 3:1 ratio by weight, (b) carboxylated polyvinyl acetate copolymer and hydroxypropyl methyl cellulose are present in a ratio of 1:1 to 1:10 parts by weight, the copolymer having preferably 3-5% carboxyl groups and a molecular weight range of about 45,000-100,000, (c) ethyl cellulose and polyvinyl pyrrolidone are present in a ratio of 1:100 to 2:1 parts by weight, (d) ethylene oxide-polypropylene glycol condensation products are present in a ratio of 0.1-5%w/v of the fluid composition, (e) triethyl citrate is present in a ratio of 0.1-10%w/v of the fluid composition. For the method of applying the composition, see Division A5. Specifications 762,229, 785,387, 978,264 and U.S.A. Specification 2,648,609 are referred to.ALSO:A composition suitable as a glossing agent for tablets comprises hydroxypropyl methyl cellulose containing 5-15% by weight of 2-hydroxypropoxyl groups and 27-32% by weight of methoxyl groups, and/or ethyl cellulose containing 42 to 49.5% by weight of ethoxyl groups, and a non-aqueous solvent.  Film-forming polymers and plasticizers may also be present. Polymers specified include a carboxylated polyvinyl acetate copolymer, polyvinyl pyrrolidone, cellulose acetate-phthalate, acetatepropionate, and acetate-butyrate; maleic anhydride - ethylene copolymers; carboxylated styrene copolymers; ethylene oxide copolymers; polyvinyl pyrrolidone-vinyl acetate copolymers; polyvinyl acetate copolymers; lower alkyl methacrylates; copolymers of lower alkyl acrylates with lower alkyl methacrylates; and copolymers of lower alkyl methacrylates with methacrylic acid.  A water-soluble wax, e.g. polyethylene glycol may also be used.  Specified plasticizers include triethyl citrate, ethylene oxide-polypropylene glycol condensation products especially those sold under the Registered Trade Mark "Pluronic," glycerine, propylene glycol, polyethylene glycols, ethyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate, and acetyl triethyl citrate.  Specified solvents include mixtures of ethanol with any of the solvents methylene chloride, chloroform, acetone, ethyl lactate, methyl salicylate and benzene.  In preferred compositions (a) ethyl cellulose and hydroxy propyl methyl cellulose are present in a 3 : 1 ratio by weight; (b) carboxylated polyvinyl acetate copolymer and hydroxypropyl methyl cellulose are present in a ratio of 1 : 1 to 1 : 10 parts by weight, the copolymer having preferably 3-5% carboxyl groups and a molecular weight range of about 45,000-100,000, (c) ethyl cellulose and polyvinyl pyrrolidone are present in a ratio of 1 : 100 to 2 : 1 parts by weight; (d) ethylene oxide polypropylene glycol condensation products are present in a ratio of 0.1-5% w./v. of the fluid composition; (e) triethyl citrate is present in a ratio of 0.1-10% w./v. of the fluid composition.  The composition is air-coated on to previously coated tablets in known manner, and imparts a gloss and a protective coat thereto.  Specifications 762,229, 785,387, 978,264 and U.S.A. Specification 2,648,609 are referred to.