Imageable element and composition comprising thermally reversible polymers
View Patent ↗The present invention also includes an imageable element, comprising a substrate and a thermally imageable composition comprising a thermally sensitive polymer which exhibits an increased solubility in an aqueous developer solution upon heating. The thermally sensitive polymer includes at least one covalently bonded unit and at least one thermally reversible non-covalently bonded unit, which includes a two or more centered H-bond within each of the non-covalently bonded unit. The present invention also includes a method of producing the imaged element. The present invention still further includes a thermally imageable composition comprising comprising a thermally sensitive polymer according to the present invention and a process for preparing the thermally sensitive polymer, which is a supramolecular polymer. The process includes contacting a hydrocarbyl-substituted isocytosine and a diisocyanate to produce a mono-adduct and contacting the mono-adduct and a polyfunctional material to produce the supramolecular polymer.
1. An imageable element comprising:
a substrate; and
a thermally imageable composition coated on a surface of said substrate; wherein said thermally imageable composition comprises
a thermally sensitive supramolecular polymer which exhibits an increased solubility in an aqueous developer solution upon heating, said thermally sensitive supramolecular polymer comprising:
at least one covalently bonded unit; and
at least one thermally reversible non-covalently bonded unit, which includes a two or more centered H-bond within each said non-covalently bonded unit.
2. The imageable element of claim 1 , wherein said two or more centered H-bond is a four centered H-bond.
3. The imageable element of claim 2 , wherein said four-centered H-bond comprises two isocytosine groups.
4. The imageable element of claim 1 , wherein said covalently bonded unit is derived from a polyfunctional material selected from the group consisting of: polyfunctional phenolic resin, acrylic resin, polyester resin, polyurethane resin, and a combination thereof.
5. The imageable element of claim 4 , wherein said polyfunctional phenolic resin is selected from the group consisting of:
phenol/cresol novolak, polyvinyl phenol polymer, vinyl phenol/hydrocarbyl acrylate copolymer, and a mixture thereof.
6. The imageable element of claim 1 , wherein said thermally sensitive polymer comprises a supramolecular polymer derived from a monomer of the formula:
wherein each R 1 and R 2 is independently selected from the group consisting of: hydrogen and hydrocarbyl;
Y is a hydrocarbyl one derived from a diisocyanate represented by the formula Y(NCO) 2 ;
R 3 is a phenolic residue derived from a polyfunctional phenolic resin represented by the formula R 3 (OH) n ; and
n is at least 1.
7. The imageable element of claim 6 , wherein said polyfunctional phenolic resin is selected from the group consisting of phenol/cresol novolak, polyvinyl phenol polymer, vinyl phenol/hydrocarbyl acrylate copolymer, and a mixture thereof.
8. The imageable element of claim 6 , wherein said diisocyanate is selected from the group consisting of: isophorone diisocyanate, methylene-bis-phenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, tetramethylxylylene diisocyanate, dimers thereof, adducts thereof with diols, and mixtures thereof.
9. The imageable element of claim 6 , wherein n is 1, 2 or 3.
10. The imageable element of claim 1 , further comprising a photothermal converter material.
11. The imageable element of claim 1 , further comprising between said substrate and said thermally imageable composition a bottom layer that is soluble or dispersible in a developer.
12. A thermally imageable composition comprising: a thermally sensitive supramolecular polymer of the formula:
wherein
each R 1 and R 2 is independently selected from the group consisting of hydrogen and hydrocarbyl;
Y is a hydrocarbylene derived from a diisocyanate represented by the formula Y(NCO) 2 ;
R 3 is a phenolic residue derived from a polyfunctional phenolic resin represented by the formula R 3 (OH) n ; and
n is at least 1.
13. A process for preparing a thermally sensitive supramolecular polymer, said process comprising:
contacting a hydrocarbyl-substituted isocytosine and a diisocyanate to produce an isocytosine/isocyanate mono-adduct; and
contacting said isocytosine/isocyanate mono-adduct and a polyfunctional material selected from the group consisting of:
polyfunctional phenolic resin, acrylic resin, polyester resin, polyurethane resin, and a combination thereof,
at a temperature and for a period of tune sufficient to produce said thermally sensitive supramolecular polymer.
14. The process of claim 13 , wherein said hydrocarbyl is an alkyl of 1 to 22 carbon atoms.
15. The process of claim 13 , wherein said diisocyanate is selected from the group consisting of: isophorone diisocyanate, methylene-bis-phenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, tetramethylxylylene diisocyanate, dimers thereof, adducts thereof with diols, and mixtures thereof.
16. The process of claim 13 , wherein said polyfunctional phenolic resin is selected from the group consisting of: phenol/cresol novolak, polyvinyl phenol polymer, vinyl phenol/hydrocarbyl acrylate copolymer, and a mixture thereof.
17. A thermally sensitive supramolecular polymer derived from a monomer of the formula:
wherein each R 1 and R 2 is independently selected from the group consisting of hydrogen and hydrocarbyl;
Y is a hydrocarbylene derived from a diisocyanate represented by the formula Y(NCO) 2 ;
R 3 is a phenolic residue derived from a polyfunctional phenolic resin represented by the formula R 3 (OH) n ; and
n is at least 1.