Dry-film negative photoresist having amidized styrene-maleic anhydride binder material

Claim 2

A DRY-FILM NEGATIVE PHOTORESIST COMPRISING (1) A CARRIER FILM, (2) A PHOTOSENSITIVE LAYER CARRIED ON THE CARRIER FILM THAT IS HEAT-SOFTENABLE AND ADHEREABLE TO A METAL SUBSTRATE, REACTS WHEN EXPOSED TO AN IMAGEWISE PATTERN OF LIGHT TO PROVIDE IMAGEWISE DIFFERENTIAL REMOVABILITY FROM THE METAL SUBSTRATE IN AN AQUEOUS DEVELOPING BATH, AND COMPRISES (A) 100 PARTS BY WEIGHT OF THE REACTION PRODUCT OF A STYRENE-MALEIC ANHYDRIDE COPOLYMER AND DIALKYLAMINE IN WHICH THE ALKYL GROUP HAS 4 TO 8 CARBON ATOMS, THE STYRENE-MALEIC ANHYDRIDE MER HAS A MOLECULAR WEIGHT OF ABOUT 1.000 TO 10.000, AND BETWEEN ABOUT ONE-THIRD AND TWO-THIRDS OF THE ANHYDRIDE GROUPS ARE REACTED WITH THE DIALKYLAMINE, (B) ABOUT 50 TO 200 PARTS BY WEIGHT OF COMPATIBLE PHOTOPOLYMERIZABLE MONOMER DISPERSED IN THE BINDER MATERIAL, AND (C) A CATALYTIC AMOUNT OF A PHOTOINITIATOR FOR INITIATING IMAGEWISE REACTION OF THE PHOTOPOLYMERIZABLE MONOMER UPON IMAGEWISE REACTION OF THE PHOTOPHOTOSENSITIVE LAYER TO LIGHT, AND (3) A PROTECTIVE COVER FILM DISPOSED OVER THE PHOTOSENSITIVE LAYER.

Claim 3

A photoresist of claim 1 in which the photopolymerizable monomer comprises a chemically mixed acrylic acid/methyacrylic acid ester of tris-(2-hydroxyethyl)isocyanurate.

Claim 4

A photoresist of claim 1 in which the dialkylamine is di-n-hexylamine.

Claim 5

A photopolymerizable composition useful as a negative photoresist, and that in film form is heat-softenable and adhereable to a copper substrate, and reacts when exposed to an imagewise pattern of light to provide imagewise differential removability from the copper substrate iN an aqueous developing bath, comprising (a) 100 parts by weight of the reaction product of a styrene-maleic anhydride copolymer and dialkylamine in which the alkyl group has 4 to 8 carbon atoms, the styrene-maleic anhydride copolymer has a molecular weight of about 1,000 to 10, 000, and between about one-third and two-thirds of the anhydride groups are reacted with the dialkylamine; (b) about 50 to 200 parts by weight of a compatible photopolymerizable monomer dispersed in the binder material, said monomer having on the average between about 2 and 4 terminal ethylenically unsaturated groups by which the photopolymerizable monomer undergoes chain-propagating addition polymerization in the presence of actinic radiation; and (c) a catalytic amount of a photoinitiator that initiates and promotes imagewise reaction of the photopolymerizable monomer upon imagewise exposure of the photopolymerizable composition to light.

Claim 6

A photopolymerizable composition useful as a negative photoresist, and that in film form is heat-softenable and adhereable to a copper substrate, and reacts when exposed to an imagewise pattern of light to provide imagewise differential removability from the copper substrate iN an aqueous developing bath, comprising (a) 100 parts by weight of the reaction product of a styrene-maleic anhydride copolymer and dialkylamine in which the alkyl group has 4 to 8 carbon atoms, the styrene-maleic anhydride copolymer has a molecular weight of about 1,000 to 10, 000, and between about one-third and two-thirds of the anhydride groups are reacted with the dialkylamine; (b) about 50 to 200 parts by weight of a compatible photopolymerizable monomer dispersed in the binder material, said monomer having on the average between about 2 and 4 terminal ethylenically unsaturated groups by which the photopolymerizable monomer undergoes chain-propagating addition polymerization in the presence of actinic radiation; and (c) a catalytic amount of a photoinitiator that initiates and promotes imagewise reaction of the photopolymerizable monomer upon imagewise exposure of the photopolymerizable composition to light.

Claim 7

A photopolymerizable composition of claim 4 in which the photopolymerizable monomer comprises a chemically mixed acrylic acid/methacrylic acid ester of tris-(2-hydroxyethyl)isocyanurate.

Claim 8

A photopolymerizable composition of claim 4 in which the dialkylamine is di-n-hexylamine.