Cellulose substrates with transparentized area and method of making same

Claim 3

A method according to claim 1 wherein the polyepoxide is selected from ##STR16## wherein R is a straight or branched chain, saturated or unsaturated C 1 -C 6 alkylene.

Claim 4

A method according to claim 1 wherein the vinyl ether is selected from vinyl pyrrolidone, hydroxybutyl vinyl ether, cyclohexandimethanol divinyl ether, polyester vinyl ether, fluoroalkyl vinyl ether, urethane divinyl ether, triethyleneglycol divinyl ether, vinyl/ether terminated urethane monomers and oligomers, or vinyl ether terminated ester monomers and oligomers.

Claim 5

A method according to claim 1 wherein the free radical catalyst is selected from 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane, benzoin ether benzophenone, methyl diethanolaminedimethylquinoxiline 4,4'-bis (dimethylaminebenzophenone, 2,2-diethoxyacetophenone, or t-butyltrichloroacetophenone.

Claim 6

A method according to claim 1 wherein the living cationic catalyst is a triarylsulfonium salt or a diaryl iodonium salt of the formula: [Ar.sub.x Q.sup.+ ].sub.y Z.sub.y.sup.- where Ar is an aromatic radical, each independently having optional substitution; Q is a sulfur atom or iodine atom; x is 3 when Q is a sulfur atom; x is 2 when Q is an iodine atom; y is 1 or2; and Z is SbF 6 or PF 6 .

Claim 7

A method according to claim 5 wherein the wherein the living cationic catalyst is selected from: ##STR17##

Claim 8

A method according to claim 1 wherein the transparentizing composition further includes an oligomer, a prepolymer, or mixtures thereof.

Claim 9

The method of claim 7 wherein the prepolymer is selected from the group styrene-maleic anhydride prepolymer, styrene-acrylic acid prepolymer, or styrene-methacrylic acid prepolymer.

Claim 10

The method of claim 7 wherein the oligomer is selected from styrene-acrylic acid oligomer or urethane acrylate oligomer.

Claim 11

A method according to claim 1 wherein the transparentizing composition further includes an additive or mixture of additives.

Claim 12

A method according to claim 10 wherein the additive is a fluorocarbon or a silicon prepolymer.

Claim 13

A method according to claim 10 wherein the transparentizing composition further includes an oligomer, prepolymer, of mixtures thereof.

Claim 14

A method according to claim 1 wherein the cationic catalyzable constituent comprises at least one of a polyepoxide.

Claim 15

A method according to claim 1 wherein the cationic catalyzable constituent comprises at least one of a vinyl ether in admixture with at least one of a polyepoxide.

Claim 16

A method according to claim 1 wherein the cationic catalyzable constituent comprises at least one of a vinyl ether.

Claim 17

A method according to claim 1 wherein the transparentizing composition comprises: a) from about 30% to about 40% of at least one of a polyepoxide; b) from about 50% to about 60% of at least one of a compound of Formula I; c) from about 3% to about 8% of at least one of a free radical catalyst; and d) from about 3% to about 8% of at least one of a living cationic catalyst.

Claim 19

A method according to claim 17 wherein the radiation-curable transparentizing composition of the present invention comprises: a) from about 30% to about 32% of a polyepoxide of the formula ##STR20## b) from about 52% to about 55% of tripropyleneglycol diacrylate; c) from about 4% to about 5% of pentacrylate; d) about 4.5% of 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula ##STR21##

Claim 20

A method according to claim 18 wherein the radiation-curable transparentizing composition of the present invention comprises: a) about 31.5% of a polyepoxide of the formula ##STR22## b) about 54% of tripropyleneglycol diacrylate; c) about 4.5% of pentacrylate; d) about 4.5% of 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula ##STR23##20.

Claim 21

A method according to claim 1 wherein the composition is applied to the substrate as a 100% solids liquid.

Claim 22

A method according to claim 1 wherein the composition has a refractive index of about 1.5 when cured.

Claim 23

A cellulosic substrate having at least one transparentized portion, said transparentized portion comprising an area of said substrate which has been impregnated with a polymerizable transparentizing material comprising: i) a cationic catalyzable constituent selected from a vinyl ether, 2) a polyepoxide, 3) a mixture of vinyl ethers, 4) a mixture of polyepoxides, or 5) a mixture of at least one of a vinyl ether and at least one of a polyepoxide; ii) a free radical catalyzable constituent selected from at least one compound of the Formula I: ##STR24## wherein, R" is any mono- or polyfunctional organic radical; R is H or CH 3 ; R' is H or --C(O)C(R)═CH 2 , with the proviso that --C(O)C(R)═CH 2 occurs at least once; x is an integer 0-4 and indicates the number of functional groups on R" which are reactive with ethylene or propylene oxide; z is an integer 1-4 and may vary independently of x and n; n is an integer 0-20 and is independent of x and z; and wherein if any of R, R', or R" are greater than one, their identities and the number of each may be the same or different; iii) a catalyst constituent comprising at least one free radical catalyst and at least one living cationic catalyst; wherein the transparentizing composition has been cured with radiation.

Claim 24

A cellulosic substrate having at least one transparentized portion, said transparentized portion comprising an area of said substrate which has been impregnated with a polymerizable transparentizing material comprising: i) a cationic catalyzable constituent selected from a vinyl ether, 2) a polyepoxide, 3) a mixture of vinyl ethers, 4) a mixture of polyepoxides, or 5) a mixture of at least one of a vinyl ether and at least one of a polyepoxide; ii) a free radical catalyzable constituent selected from at least one compound of the Formula I: ##STR24## wherein, R" is any mono- or polyfunctional organic radical; R is H or CH 3 ; R' is H or --C(O)C(R)═CH 2 , with the proviso that --C(O)C(R)═CH 2 occurs at least once; x is an integer 0-4 and indicates the number of functional groups on R" which are reactive with ethylene or propylene oxide; z is an integer 1-4 and may vary independently of x and n; n is an integer 0-20 and is independent of x and z; and wherein if any of R, R', or R" are greater than one, their identities and the number of each may be the same or different; iii) a catalyst constituent comprising at least one free radical catalyst and at least one living cationic catalyst; wherein the transparentizing composition has been cured with radiation.

Claim 25

A cellulosic substrate according to claim 22 wherein the transparentizing composition comprises: a) from about 30% to about 40% of at least one of a polyepoxide; b) from about 50% to about 60% of at least one of a compound of Formula I; c) from about 3% to about 8% of at least one of a free radical catalyst; and d) from about 3% to about 8% of at least one of a living cationic catalyst.

Claim 26

A cellulosic substrate according to claim 23 wherein the transparentizing composition comprises: a) from about 30% to about 40% of a polyepoxide of the formula ##STR25## b) from about 50% to about 60% of tripropyleneglycol diacrylate; c) from about 3% to about 6% of pentacrylate; d) about 4.5% of 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula ##STR26##

Claim 27

A cellulosic substrate according to claim 24 wherein the radiation-curable transparentizing composition of the present invention comprises: a) from about 30% to about 32% of a polyepoxide of the formula ##STR27## b) from about 52% to about 55% of tripropyleneglycol diacrylate; c) from about 4% to about 5% of pentacrylate; d) about 4.5% of 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula ##STR28##

Claim 28

A cellulosic substrate according to claim 25 wherein the radiation-curable transparentizing composition of the present invention comprises: a) about 31.5% of a polyepoxide of the formula ##STR29## b) about 54% of tripropyleneglycol diacrylate; c) about 4.5% of pentacrylate; d) about 4.5% of 2-hydroxy- 1-[4-(hydroxy-ethoxy)phenyl]-2-methyl- 1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula ##STR30##

Claim 29

A cellulosic substrate according to claim 26 wherein the transparentizing composition comprises: a) about 31.5% of a polyepoxide of the formula ##STR31## b) about 54% of tripropyleneglycol diacrylate; c) about 4.5% of pentacrylate; d) about 4.5% of 2-hydroxy-1-[4-(hydroxy-ethoxy)phenyl]-2-methyl-1-propane; and e) about 5.5% of a triarylsulfonium hexafluorophosphate salt of the formula: ##STR32##

Claim 30

The substrate of claim 22 wherein the transparentized portion has a thickness in the range of from about 0.0005 to about 0.002 inches.

Claim 31

The substrate of claim 22 wherein the substrate is in the form of an envelope or mailer having at least a first ply and a second ply, with the transparentized portion on the first ply.

Claim 34

A method according to claim 30 wherein the cationic catalyzable constituent comprises at least one of a polyepoxide.

Claim 35

A method according to claim 30 wherein the cationic catalyzable constituent comprises at least one of a vinyl ether in admixture with at least one of a polyepoxide.