A negative-working photosensitive resin composition including an epoxy group-containing resin, a metal oxide, and a cationic polymerization initiator, in which a photosensitive resin film having a film thickness of 20 μm obtained by applying the negative-working photosensitive resin composition onto a silicon wafer and performing a bake treatment at 90° C. for 5 minutes has a Martens hardness of less than 235 [N/mm.sup.2], and when a viscoelasticity of a cured film, which is obtained by exposing the photosensitive resin film to i-rays at an irradiation amount of 200 mJ/cm.sup.2, performing a bake treatment after the exposure at 90° C. for 5 minutes, and then performing a bake treatment at 200° C. for 1 hour to cure the photosensitive resin film, is measured at a frequency of 1.0 Hz, a tensile elastic modulus (E*) of the cured film at a temperature of 175° C. is 2.1 [GPa] or more.

A negative-working photosensitive resin composition including an epoxy group-containing resin, a metal oxide, and a cationic polymerization initiator, in which a photosensitive resin film having a film thickness of 20 μm obtained by applying the negative-working photosensitive resin composition onto a silicon wafer and performing a bake treatment at 90° C. for 5 minutes has a Martens hardness of less than 235 [N/mm.sup.2], and when a viscoelasticity of a cured film, which is obtained by exposing the photosensitive resin film to i-rays at an irradiation amount of 200 mJ/cm.sup.2, performing a bake treatment after the exposure at 90° C. for 5 minutes, and then performing a bake treatment at 200° C. for 1 hour to cure the photosensitive resin film, is measured at a frequency of 1.0 Hz, a tensile elastic modulus (E*) of the cured film at a temperature of 175° C. is 2.1 [GPa] or more.

A photosensitive composition capable of forming a cured product with high transparency, a cured product of the photosensitive composition, and a method for producing the cured product using the photosensitive composition. In a photosensitive composition including a base component having photopolymerizability and a photopolymerization initiator, a phosphine oxide compound and an oxime ester compound as a photopolymerization initiator are used in combination such that the ratio of the mass W2 of the oxime ester compound is 35% by mass or more relative to sum of a mass W1 of the phosphine oxide compound and the mass W2 of the oxime ester compound.

The present invention relates to a method for manufacturing a flexible photo-patterned mask. The method includes a) coating a photoresist composition on a substrate to form a photoresist film, b) exposing the photoresist film to pattern the photoresist film, c) developing the patterned photoresist film, and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings.

A new photosensitive resin composition based on a polysiloxane, that is, a negative photosensitive resin composition is provided. A negative photosensitive resin composition includes (A) a polysiloxane compound containing a first structural unit represented by the following general formula (1), (B) a photoinduced curing accelerator, and (C) a solvent.

[(R.sup.x).sub.bR.sup.1.sub.mSiO.sub.n/2]  (1)

A new photosensitive resin composition based on a polysiloxane, that is, a negative photosensitive resin composition is provided. A negative photosensitive resin composition includes (A) a polysiloxane compound containing a first structural unit represented by the following general formula (1), (B) a photoinduced curing accelerator, and (C) a solvent.

[(R.sup.x).sub.bR.sup.1.sub.mSiO.sub.n/2]  (1)

A photosensitive material includes: a compound A having a carboxy group, in which the compound A includes a polymer including a repeating unit derived from (meth)acrylic acid, and a content of the carboxy group in a photosensitive layer which is formed from the photosensitive material is reduced by irradiation with an actinic ray or a radiation.

A photosensitive material includes: a compound A having a carboxy group, in which the compound A includes a polymer including a repeating unit derived from (meth)acrylic acid, and a content of the carboxy group in a photosensitive layer which is formed from the photosensitive material is reduced by irradiation with an actinic ray or a radiation.

A method to control the density of a three-dimensional photonic crystal template involves changing the irradiation time from at least four laser beams to yield a periodic percolating matrix of mass and voids free of condensed matter from a photoresist composition. The photoresist composition includes a photoinitiator at a concentration where the dose or irradiation is controlled by the irradiation time and is less than the irradiation time that would convert all photoinitiator to initiating species such that the density of the three-dimensional photonic crystal template differs for different irradiation times. A deposition of reflecting or absorbing particles can be patterned on the surface of the photoresist composition to form a template with varying densities above different areas of the substrate.

A siloxane polymer comprising polysiloxane, silphenylene, isocyanuric acid, and polyether skeletons in a backbone and having an epoxy group in a side chain is provided. A photosensitive resin composition comprising the siloxane polymer and a photoacid generator is coated to form a film which can be patterned using radiation of widely varying wavelength. The patterned film has high transparency and light resistance.