Transparent liquid absorbent materials for use as ink-receptive layers

Claim 2

A recording sheet comprising a transparent support bearing on at least one major surface thereof a transparent ink-receptive layer comprising: (1) from about 92 to about 99.5% by weight of a water-soluble copolymer; and (2) from about 0.5 to about 8% by weight of a polyfunctional aziridine crosslinking agent; said water-soluble copolymer having been crosslinked after being coated onto said support.

Claim 3

A recording sheet comprising a transparent support bearing on at least one major surface thereof a transparent ink-receptive layer comprising: (1) from about 92 to about 99.5% by weight of a water-soluble copolymer; and (2) from about 0.5 to about 8% by weight of a polyfunctional aziridine crosslinking agent said water-soluble copolymer having been crosslinked after being coated onto said support, said water-soluble copolymer comprising: (a) from about 0.5 to about 20% by weight of at least one ethylenically unsaturated monomer having acidic groups, up to 100% of said acidic groups being present as an ammonium salt or a salt prepared from a volatile amine; (b) from about 10 to about 99.5% by weight of at least one monomer selected from the group consisting of polar compounds containing nitrogen groups; and (c) up to about 70% by weight of a hydrophilic, ethylenically unsaturated alkylester.

Claim 4

A recording sheet comprising a transparent support bearing on at least one major surface thereof a transparent ink-receptive layer comprising: (1) from about 92 to about 99.5% by weight of a water-soluble copolymer; and (2) from about 0.5 to about 8% by weight of a polyfunctional aziridine crosslinking agent said water-soluble copolymer having been crosslinked after being coated onto said support, said water-soluble copolymer comprising: (a) from about 0.5 to about 20% by weight of at least one ethylenically unsaturated monomer having acidic groups, up to 100% of said acidic groups being present as an ammonium salt or a salt prepared from a volatile amine; (b) from about 10 to about 99.5% by weight of at least one monomer selected from the group consisting of polar compounds containing nitrogen groups; and (c) up to about 70% by weight of a hydrophilic, ethylenically unsaturated alkylester.

Claim 5

The recording sheet of claim 2, wherein said at least one ethylenically unsaturated monomer having acidic groups are selected from the group consisting of: (a) acrylic acid, methacrylic acid, p-styrene sulfonic acid, 2-acrylamido-2-methyl propane sulfonic acid; (b) quaternary ammonium salts of acids described in (a); (c) salts prepared from a volatile amine of acids described in (a); and (d) ammonium salts of acid monomers having the structure: ##STR11## wherein R 1 represents H or --CH 3 , R 2 represents H or an alkyl group having up to 10 carbon atoms, and X represents --COONH 4 , or --SO 3 NH 4 .

Claim 6

The recording sheet of claim 2, wherein said polar compounds containing nitrogen groups are selected from the group consisting of: (a) vinyl lactams having the repeating structure: ##STR12## wherein n represents the integer 2 or 3, and (b) amides, having the structures: ##STR13## wherein R 1 represents H or --CH 3 , R 2 represents H or an alkyl group having up to 10 carbon atoms, and R 3 represents H, alkyl group having up to 10 carbon atoms, hydroxyalkyl group, or alkoxyalkyl group having the structure --(CH 2 ) m --OR 2 where m represents an integer from 1 to 3, inclusive.

Claim 7

The recording sheet of claim 4, wherein said polar compound is N-vinyl-pyrrolidone.

Claim 8

The recording sheet of claim 2, wherein said hydrophilic, ethylenically unsaturated alkylester is selected from the group consisting of: (a) alkoxy alkylacrylates, hydroxy alkylacrylates, alkoxy alkylmethacryaltes, or hydroxy alkylmethacrylates having the structure: ##STR14## wherein p represents an integer from 1 to 4, inclusive, R 1 represents H or --CH 3 , and R 4 represents H or alkyl group having 1 to 4 carbon atoms; and (b) alkoxy acrylates or alkoxy methacrylates having the structure: ##STR15## wherein q represents an integer from 5 to 25, inclusive, and R 1 represents H or --CH 3 .

Claim 9

The recording sheet of claim 1, wherein said polyfunctional aziridine crosslinking agent is selected from the group consisting of trimethylolpropane-tris-(β-(N-aziridinyl)propionate), pentaerythritol-tril-(β-(N-aziridinyl)propionate), and trimethylolpropane-tris-(β-(N-methylaziridinyl propionate).

Claim 10

The recording sheet of claim 1, wherein the weight of said polyfunctional aziridine crosslinking agent ranges from about 1.0 to about 6.0% by weight of the layer.

Claim 11

The recording sheet of claim 1, wherein said transparent support is a polyester film.