A photosensitive resin composition comprises a component (A): a resin having a phenolic hydroxyl group; a component (B): an aliphatic compound having two or more functional groups, the functional groups being one or more group selected from an acryloyloxy group, a methacryloyloxy group, a glycidyloxy group and a hydroxyl group; a component (C): a photosensitive acid generator; and a component (D): an inorganic filler having an average particle diameter of 100 nm or less.

A radiation curable inkjet ink comprising a polymerizable compound, a photoinitiator characterized in that the inkjet ink further comprises a di- or multifunctional alkoxysilane and a monofunctional alkoxysilane functionalized with a group selected from the group consisting of an epoxide and an oxetane.

A circuit board according to an embodiment comprises: an insulating layer including first to third regions; an outer layer circuit pattern disposed on the upper surface of the first to third regions of the insulating layer; and a solder resist including a first part disposed in the first region of the insulating layer, a second part disposed in the second region, and a third part disposed in the third region, wherein the outer layer circuit pattern has a first height, the third part of the solder resist is disposed on the upper surface of the outer layer circuit pattern to have a second height, the first region includes a first sub-region and a second sub-region, the first part includes a first sub-part disposed in the first sub-region and a second sub-part disposed in the second sub-region, the upper surface of the first sub-part is located to be higher than the upper surface of the outer layer circuit pattern and lower than the upper surface of the third part, the upper surface of the second sub-part is located to be lower than the upper surface of the outer layer circuit pattern, and the surface roughness of the third part of the solder resist is different from the surface roughness of the first part of the solder resist.

Provided is a curable composition for inkjet which can have a prolonged pot life even under an environment in an inkjet device that is warmed to 50° C. or higher and which can be cured into a cured product having improved heat resistance and insulation reliability, in spite of the fact that a thermally curable compound is used in the curable composition. The curable composition for inkjet according to the present invention contains a photocurable compound, a thermally curable compound, a photopolymerization initiator and a thermal curing agent and does not contain a solvent or contains the solvent, wherein the content of the solvent in 100% by weight of the curable composition is 1% by weight or less when the curable composition for inkjet contains the solvent, the photocurable compound contains a polyfunctional compound having at least two (meth)acryloyl groups, and the thermal curing agent is an aromatic amine having at least one benzene ring and at least two amino groups.

A printed wiring board includes a laminated base material including an insulating layer and a conductor layer formed on the insulating layer, and a solder resist layer laminated on the laminated material and including photosensitive resin. The resist layer has surface portion and portion in contact with the laminated material, the conductor layer has pattern including conductor pads in contact with the resist layer such that the pads are positioned in openings in the resist layer, and the resist layer satisfies a first condition that a chemical species derived from a photopolymerization initiator has concentration higher in the portion in contact with the laminated material than concentration in the surface portion and/or a second condition that the chemical species derived from the initiator in the portion in contact with the laminated material has photopolymerization initiating ability higher than a chemical species derived from a photopolymerization initiator in the surface portion.

An ultraviolet curing type coating resin composition having all of respective beneficial features of excellent state in chemical resistance, under high temperature, against human skin protection creams containing a mixture of alkyl esters of benzoic acid, as represented by Neutrogena Cream (registered trademark), excellent state in gas barrier property against metal-corrosive gases as represented by sulfur-containing gases, and excellent state in flexibility that accommodates three-dimensional shape forming processing is demanded, includes an ultraviolet curing type coating resin composition containing an unsaturated-group-containing acrylic resin, with a weight average molecular weight of 5000 to 70000, a number of (meth)acrylate functional groups per molecule of 5 to 40, a hydroxyl value of 2 to 200 mgKOH/g, and with a glass transition temperature of 20 to 90° C., a volatile organic solvent, and a photopolymerization initiator.

Provided is a method for manufacturing a substrate having a concave pattern to be used for forming a high-definition pattern while suppressing wet-spreading and bleeding of a film-forming ink, provided is a composition to be used for manufacturing the substrate, and provided are a method for forming a conductive film, an electronic circuit, and an electronic device. The method for manufacturing a substrate having a concave pattern includes: (i) a step of applying, on a substrate 1, a composition containing a polymer having an acid-dissociable group and an acid generator to form a coating film 2 and (ii) a step of irradiating a predetermined portion of the coating film 2 with radiation. The method for forming a conductive film includes applying a conductive film-forming ink on the concave pattern formed in the exposed portion of the coating film 2 and heating the ink to form a pattern 6. The electronic circuit and the electronic device are provided by using the method for forming a conductive film.

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 invention provides an inkjet method for producing a solder mask in the manufacture of a Printed Circuit Board. By using a solder mask inkjet ink containing at least one photoinitiator, at least one free radical polymerizable compound and at least one mercapto functionalized carboxylic acid as adhesion promoter, a high quality solder mask withstanding the high thermal stress during the soldering process while maintaining excellent physical properties, may be produced.

A laminated structure for use as a thy film photoresist, which includes a supporting layer, a photosensitive resin layer and a protective layer. The protective layer is a polyester film that has a maximum surface roughness between 1,500 nm and 2,500 nm, and a sheet resistance between 1×10.sup.8Ω/□ and 1×10.sup.12Ω/□. The laminated structure is particularly applicable to the manufacture of a photosensitive device and a circuit of a printed circuit board or a lead frame.