The present invention relates to a method for manufacturing a cliché for offset printing and a cliché for offset printing.

A low dielectric constant (Dk) and dissipation factor (Df) of solder resistant mask composition having excellent photo and thermocurability, and high developability resolution with an alkaline aqueous solution, wherein the dielectric constant is below 3.20 (1 GHz), and the dissipation factor is less than 0.015 (1 GHz); and wherein the composition comprises (A) a photopolymerizable prepolymer; (B) a photopolymerizable vinyl monomer; (C) an epoxy compound; (D) a photopolymerization initiator; (E) an inorganic filler; (F) a catalyst; and (G) an organic solvent.

Compositions including hard magnetic photoresists, soft photoresists, hard magnetic elastomers and soft magnetic elastomers are provided.

Provided is a photosensitive resin composition that contains (A) a photobase generator and (B) an alkali-soluble epoxy compound, wherein the photobase generator (A) contains a compound represented by formula (2-1) and the alkali-soluble in epoxy compound (B) is an epoxy compound obtained by reacting (c) a polybasic acid anhydride with a product of a reaction between (a) an epoxy compound having two or more epoxy groups in the molecule and (b) a compound having one or more by hydroxyl groups and one carboxyl group in the molecule.

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Disclosed is a photosensitive resin composition for an optical waveguide containing a resin component and a photoacid generator. In the photosensitive resin composition, the resin component is constituted of an epoxy resin component containing both an aromatic epoxy resin and an aliphatic epoxy resin, and the content of the aromatic epoxy resin is 55 wt. % or more and less than 80 wt. % of the entirety of the epoxy resin component and the content of the aliphatic epoxy resin is more than 20 wt. % and 45 wt. % or less of the entirety of the epoxy resin component. Accordingly, for example, when a core layer of an optical waveguide is formed using the disclosed photosensitive resin composition for an optical waveguide, a core layer of an optical waveguide having satisfactorily low tackiness and high transparency while maintaining satisfactory roll-to-roll compatibility and a high resolution patterning property can be formed.

A resin composition and a use thereof are provided. The resin composition includes, in parts by weight, 100 parts of an alkali-soluble resin, 5-30 parts of acrylate monomers, 0.1-10 parts of photoinitiator, 10-30 parts of a first epoxy resin and 0-15 parts of a second epoxy resin. The first epoxy resin is a low-dielectric epoxy resin with a dielectric constant of <3.5 and the second epoxy resin is different from the first epoxy resin. With the addition of the low epoxy resin with the dielectric constant of >3.5, and by adjusting the ratio of the components, the resin composition significantly reduces the dielectric constant and dielectric loss, the dielectric constant is reduced to 3.0 or less, and the dielectric loss is reduced to 0.008 or less.

The present invention relates to provision of a photosensitive resin composition, a photosensitive resin composition for photo via formation, and a photosensitive resin composition for interlayer insulating layer, each of which is excellent in resolution of via, adhesion strength to plated copper, crack resistance, and electrical insulation reliability. In addition, the present invention relates to provision of a photosensitive resin film and a photosensitive resin film for interlayer insulating layer, each of which is composed of the aforementioned photosensitive resin composition. Furthermore, the present invention relates to provision of a multilayer printed wiring board and a semiconductor package, and to provision of a method for producing the aforementioned multilayer printed wiring board. Specifically, the photosensitive resin composition is a photosensitive resin composition containing (A) a photopolymerizable compound having an ethylenically unsaturated group and (B) a polymerization initiator, wherein the photopolymerizable compound (A) having an ethylenically unsaturated group includes (A1) a photopolymerizable compound having an acidic substituent and an alicyclic structure together with an ethylenically unsaturated group.

A protective film formation composition contains a polymer having a unit structure represented by formula (1-1), a compound or a polymer having phenolic hydroxy group other than catechol, (C) a thermal acid generator, and (D) a solvent.

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(Ar represents a benzene, naphthalene, or an anthracene ring; R1 represents a hydroxy, mercapto,amino, halogeno, or an alkyl group that has 1-10 carbon atoms and that may be substituted or interrupted by a hetero atom and may be substituted by a hydroxy group; n1 represents an integer of 0-3; L1 represents a single bond or an alkylene group having 1-10 carbon atoms; E represents an epoxy group; when n2=1, T1 represents a single bond or an alkylene group having 1-10 carbon atoms and may be interrupted by an ether bond, an ester bond, or an amide bond; and when n2=2, T1 represents a nitrogen atom or an amide bond.)

A purpose of the present invention is to provide a photosensitive resin composition which retains satisfactory image resolution and gives cured objects reduced in wet-heat dissolution or contamination and having satisfactory wet-heat adhesiveness. The photosensitive resin composition of the present invention comprises: (A) a cationic photopolymerization initiator which comprises a salt of a cation with an anion represented by formula (1) (wherein R.sub.1 to R.sub.4 each independently represent a C1.sub.−18 alkyl or C.sub.6-14 aryl group, provided that at least one of R.sub.1 to R.sub.4 represents a C.sub.6-14 aryl group); and (B) an epoxy compound. R.sub.1 to R.sub.4 may be each independently either a phenyl group having one or more perfluoroalkyl groups as substituents or a phenyl group having one or more fluorine atoms as substituents. R.sub.1 to R.sub.4 may be each independently a pentafluorophenyl or bis(trifluoromethyl)phenyl group. ##STR00001##

A photosensitive epoxy resin composition for formation of an optical waveguide is provided, which contains an epoxy resin component, and a photo-cationic polymerization initiator, wherein the epoxy resin component includes a solid semi-aliphatic bifunctional epoxy resin. The optical waveguide formation photosensitive epoxy resin composition is usable as an optical waveguide forming material having higher R-to-R (roll-to-roll) adaptability (lower tackiness and uncured-state flexibility), a lower refractive index, excellent patternability, and excellent laser processability mirror forming processability).