Photoimageable compositions having improved chemical resistance and stripping ability

A negative-acting photoimageable composition, comprising:

• I) between about 30 wt % and 100% based on total weight of I) plus II) plus III) of a binder polymer having sufficient acid functionality to render the photoimageable composition developable in alkaline aqueous solution;
• II) between 0 and about 70 wt % based on total weight of I) plus II) plus III) of an addition-polymerizeable, .alpha., .beta.-ethylenically unsaturated compound(s) capable of forming a high polymer by free-radical initiated chain-propagating addition polymerization with said binder polymer I);
• and,
• III) between about 0.1 and about 20 wt % based on total weight of I) plus II) plus III) of a photoinitiator chemical system, wherein said binder polymer comprises a backbone having between about 10 and 90 mol. % anhydride residues, said anhydride residues being half-esterified to at least about 10 mol % total of said anhydride residues with a hydroxy-functional momomer or oligomer, all or a portion of said half-esterification being with a (meth)acrylate-functional hydroxy-terminated oligomer having the formula:
• ##STR5## wherein (A), (B) and (C) are in any order, (A) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms,
• (B) is either absent or comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms, the monomer composition of (B) being different than the monomer composition of (A), (A) plus (B) being formed from at least 2 monomers,
• (C) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, lactone monomers having between about 2 and 21 carbon atoms.

A binder polymer for negative-acting photoimageable compositions, comprising:

• a backbone having between about 10 and 90 mol. % anhydride residues, said anhydride residues being half-esterified to at least about 10 mol % total of said anhydride residues with a hydroxy-functional momomer or oligomer, all or a portion of said half-esterification being with a (meth)acrylate-functional hydroxy-terminated oligomer having the formula:
• ##STR6## wherein (A), (B) and (C) are in any order, (A) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms,
• (B) is either absent or comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms, the monomer composition of (B) being different than the monomer composition of (A), (A) plus (B) being formed from at least 2 monomers,
• (C) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, lactone monomers having between about 2 and 21 carbon atoms,
• said binder polymer capable of being incorporated into an alkaline aqueous developable photoimageable composition and rendering said photoimageable composition readily strippable in alkaline aqueous stripping solutions.

A negative-acting photoimageable composition, comprising:

• I) a binder polymer having sufficient acid functionality to render said photoimageable composition developable in alkaline aqueous solution;
• II) either absent or a photopolymerizable material for said binder polymer;
• and,
• III) a photoinitiator chemical system, wherein said binder polymer comprises a backbone having between about 10 and 90 mol. % anhydride residues, said anhydride residues being half-esterified to at least about 10 mol % total of said anhydride residues with a hydroxy-functional momomer or oligomer, all or a portion of said half-esterification being with a (meth)acrylate-functional hydroxy-terminated oligomer having the formula:
• ##STR7## wherein (A), (B) and (C) are in any order, n is an integer from 1 to 40,
• (A) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms,
• (B) is either absent or comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, alkoxylate monomers having between about 1 and 20 carbon atoms, the monomer composition of (B) being different than the monomer composition of (A), (A) plus (B) being formed from at least 2 monomers, and
• (C) comprises a chain formed of between about 1 and 40, linear or branched, unsubstituted or substituted, lactone or lactam monomers having between about 2 and 21 carbon atoms.

A negative-acting photoimageable composition, comprising:

• I) a binder polymer having sufficient acid functionality to render said photoimageable composition developable in alkaline aqueous solution;
• II) a photopolymerizable material for said binder polymer;
• and,
• III) a photoinitiator chemical system,
• wherein the binder polymer comprises an anhydride-functional backbone, all or a portion of said backbone being half-esterified with a (meth)acrylate functional hydroxy-terminated oligomer, in which the (meth)acrylate functionality is separated from the half-ester linkage by at least two alkoxylate groups and at least one ring opened lactone or lactam group.