Patent GB-820207-A (GB)
Title: Vinylic filler pigments
IPC: C09C1/00
Filed: 1955-08-31
Abstract: A pigment comprises a "vinylic filler" in colloidal sized particles in combination with an organic and/or inorganic colouring material. By "vinylic filler" is meant the homopolymerization and multipolymerization products, in the form of substantially rigid particles obtainable from polymerizable substances containing one or more polymerizable unsaturated linkages providing the products therefrom are crosslinked within the particles to a condition of substantially complete insolubility in organic solvents generally. The "vinylic fillers" may be chemically after-treated to introduce reactive or polar groups.  This term also includes as a multi-polymerization product the "interpolymer" type of filler, i.e. by the term "interpolymer" is meant the polymerization product produced when two or more monomers are polymerized sequentially or one or more monomers are polymerized in the presence of a polymer or when a condensation polymer is formed in the presence of a polymer, and when the components of an interpolymer are inseparable because of chemical combination the resultant polymer is known as a graft polymer.  The colouring matter may be in admixture with the filler, chemically combined with the filler or adsorbed on the surface of the filler particles.  The colouring matter may be subsequently "fixed" on the particles.  "Vinylic fillers" specified are (1) copolymers of styrene, methacrolein and divinyl benzene, (2) styrene and divinyl benzene, (3) styrene, dimethylaminoethylmethacrylate, and divinyl benzene, (4) styrene, methacrylic acid, and divinyl benzene, (5) styrene, divinyl benzene, and 4-vinylpyridine, (6) styrene, acrylonitrile, and divinyl benzene, (7) vinyl acetate and ethyleneglycoldimethacrylate, and butadiene and 4-vinyl-pyridine polymerized in the presence of (1) above, methylmethacrylate polymerized in presence of (2) above, styrene and methacrolein polymerized in presence of (3), polymer (5) above reacted with propylene oxide, butadiene polymerized in the presence of (5) above, and a condensate of urea, and formaldehyde effected in the presence of polymer (4) above and a basic catalyst.  When the colouring matter is chemically combined with the filler the reaction may be effected between an acidic polymer and a basic dyestuff or vice versa, or between a filler containing aldehyde groups and a dyestuff containing amine groups, or by coprecipitating the filler and dyestuff with a polyvalent metal or compound such as aluminium, aluminium acetate, cobalt, barium chloride, lead, lead nitrate, stannous chloride or salts of manganese, antimony, copper, or chromium and mixtures.  The pigment is generally formed in aqueous media and water-soluble acid or basic polymers may be added during or after the formation of the pigment, e.g. polyvinyl pyridine hydrochloride or sodium polyacrylate.  Condensation polymers, e.g. phenoplasts or aminoplasts, may be formed in situ during or after the preparation of the pigment.  The colouring matter may be formed in situ.  The pigment may be recovered from the aqueous medium by spray drying. The colouring matter may be organic or inorganic or a mixture. The Specification contains an extensive list of dyestuffs selected from the following classes:-acid, basic, direct, direct and development, azo, metal mordants, vat dyes including leuco esters and sulphur dyes.  All these classes of dyestuff are exemplified.  The dyestuffs may be "fixed" with salts such as the ammonium and sodium salts of tungstic, molybdic or complex phosphotungstomolybdic acid.  The Specification also contains an extensive list of inorganic pigments. Exemplified pigments are chrome yellow, Cadmium orange, Iron blue, titanium white, chrome green, silver, e.g. the nitrate, and palladium, e.g. the chloride. The "vinylic filler" pigment can be used as reinforcing fillers for natural and synthetic rubbers and resins, and thermosetting polymers such as polymers of styrene, vinyl chloride, ethylene or acrylates.  The filler may be mixed with the rubber, resin, or polymer as latices.  The polymer may be an aminoplast or phenoplast.  Latices of the "vinylic filler" pigment admixed with other film-forming latices may be used as coatings on textiles, paper, or leather.  The Specification contains a long list of suitable rubbers, resins, and polymers.  The "vinylic filler" pigment may be utilized in printing pastes for printing on textiles, paper, plastics, or leather.  The "vinylic filler" pigment can also be used in conjunction with well-known organic and inorganic pigments including metal powders and flake pigments. An extensive list of these additional pigments is given in the Specification.  The "vinylic filler" pigment may be used in paints containing drying oils, styrenated oils, maleic acid modified drying oils, and alkyd resins.