| 摘要 |
<p>1463134 Absorbent laminated pads ROHM & HAAS CO 15 March 1974 [24 April 1973 5 Sept 1973] 11587/74 Heading B5N [Also in Divisions B1-B2] A flexible absorbent pad comprises a top layer of polymeric foam material which is permeable to liquids, an underlying layer of liquid absorbent material and a bottom layer of flexible material, the polymeric foam material being a crushed foam of addition polymer which has been crushed to a thickness of from 1 to 10 mils after drying to at least a touch-dry state. The liquid absorbent material may be cellulose wadding made from wood pulp, cotton or rayon, garnetted cotton, wood or rayon fibres, crepe or tissue or organic fibres, e.g. polyolefine, polyester, acrylic or polyvinyl fibres. The bottom layer is preferably liquid impermeable and may comprise polyethylene or polypropylene. The pad may be made by forming a foam layer on a release paper, drying the foam, applying the resultant composite to the other components and passing the resultant assembly through a heated nip to crush the foam and bond the components prior to stripping off the release paper; alternatively, the foam-forming reactants may be applied to the liquid absorbent material overlying the flexible material, the foam dried and the resultant assembly passed through a heated nip. The foam, which may be pigmented, may contain conventional additives, e.g. cross-linking agents, catalysts and thickeners may be thermoplastic, cross-linkable or thermosetting and may be a copolymer of a monomer of the formula where R is hydrogen or a C 1 to C 4 alkyl and R<SP>1</SP> is a straight or branched radical of a primary or secondary alkanol, alkoxyalkanol or alkylthio alkanol, the alkanol having from 2 to 14 carbon atoms, butadiene, ethylene, propylene, vinyl acetate or vinyl chloride and a monovinyl aromatic monomer, an acrylic and/or methacrylic acid ester, a vinyl halide, vinyl nitrile, an unsaturated monocarboxylic acid, a half ester or half amide of anα,#-unsaturated dicarboxylic acid or a salt thereof. Many suitable monomers are listed, preferred monomers having the Formulae (II) where R‹ is hydrogen or a C 1 to C 4 alkyl and n is 1 to 4; (II) CH=C(R)AYNR<SP>1</SP>R<SP>2</SP>, where R is hydrogen or methyl, A is O, S, Y is a C 2 to C 4 alkylene group, R<SP>1</SP> and R<SP>2</SP> are each hydrogen or a C 1 to C 4 alkyl, (III) where R is as defined above and Z is a C 2 or C 3 alkylene group, (IV) where R and Z are as defined above and (V) where A is a C 2 to C 10 alkylene group of which at least 2 carbon atoms extend in a chain between the adjoining oxygen atoms.</p> |
