Abstract: A problem is to provide a fine resin particle formed by a simple method and capable of preventing fine resin particles from dropping out from substrates or binders and imparting scratch resistance to films, and a fine resin particle-containing composition. A solution is to provide a fine resin particle obtained by polymerizing one or two or more vinylic monomers and, in an infrared spectrum measured by an ATR method with an infrared spectrophotometer, having an absorbance ratio (B)/(A) in a range of 0.020 to 0.060 between the maximum peak height (maximum absorbance) (A) in a wavenumber range from 1700 cm?1 to 1800 cm?1 and the maximum peak height (maximum absorbance) (B) in a wavenumber range from 1600 cm?1 to 1700 cm?1.

Abstract: There are provided a resin composition for a solder resist, a solder resist film, and a circuit board that exhibit an excellent low dielectric property by a non-conventional new approach. A resin composition for a solder resist according to an embodiment of the present invention contains a thermosetting resin, an inorganic filler, and hollow resin particles, in which the hollow resin particles are contained in the resin composition for a solder resist in an amount of 1% by weight to 50% by weight.

Abstract: Provided is a hollow resin particle that has a hollow portion therein and that can exhibit excellent heat resistance. In addition, a method for producing such a hollow resin particle in a simple manner is provided. Furthermore, use of such a hollow resin particle is provided. A hollow resin particle according to an embodiment of the present invention is a hollow resin particle including a hollow portion therein, has an ether structure represented by formula (1), and has an average particle diameter of 0.1 ?m to 100 ?m. [Chem.

Abstract: There is provided hollow resin particles used in a resin composition for semiconductor members, which can be used in a resin composition for semiconductor members to provide a semiconductor member capable of exerting excellent low dielectric properties. The hollow resin particles used in a resin composition for semiconductor members according to an embodiment of the present invention are hollow resin particles having a hole part inside the particle, wherein a decreasing rate of a relative dielectric constant Dk1 of a film (F1) formulated with 80 parts by weight of polyimide and 20 parts by weight of the hollow resin particles to a relative dielectric constant Dk0 of a film (F0) formed with only the polyimide is 3% or more.

Abstract: There are provided a laminate and the like and a circuit board including the same that exhibit an excellent low dielectric property by a non-conventional new approach. The laminate according to an embodiment of the present invention is a laminate used for a core layer of a circuit board, in which the laminate does not include a buildup layer, the laminate is obtained by laminating a plurality of prepregs including a fiber base material layer and a resin layer (A) so that the prepregs are in direct contact with each other, the resin layer (A) contains an inorganic filler and hollow resin particles, and the hollow resin particles are contained in the resin layer (A) in an amount of 1% by weight to 50% by weight with respect to the total amount of the resin layer (A).

Abstract: There are provided a resin composition for semiconductor sealing, an underfill, a mold resin, and a semiconductor package that exhibit an excellent low dielectric property by a non-conventional new approach. A resin composition for semiconductor sealing according to an embodiment of the present invention is a resin composition for semiconductor sealing containing a thermosetting resin, a curing agent, an inorganic filler, and hollow resin particles, in which the hollow resin particles are contained in the resin composition for semiconductor sealing in an amount of 1% by weight to 50% by weight.

Abstract: This invention provides hollow particles having a shell containing at least one layer and having an average particle diameter of 10 to 150 nm, wherein a ratio ? between absorbance at 908 cm?1 (A908) and absorbance at 1722 cm?1 (A1722) in an infrared absorption spectrum obtained by measuring the hollow particles by ATR-FTIR (absorbance ratio ?: A908/A1722) is 0.1 or less.

Abstract: The invention has a problem of providing a fine resin particle that is useful as an anti-blocking agent or other agents, has sufficient resistance to the thermal load applied when compounded with resins, shows sufficiently lowered residual amount of unreacted monomers in the fine resin particle, and, furthermore, has a color tone that does not affect optical properties even when used in optical members, to which very high optical characteristics (colorless transparency) are required, or other members.

Abstract: Provided is a hollow resin particle that has a shell portion and a hollow portion surrounded by the shell portion and that can achieve reductions in dielectricity and dielectric loss tangent and can exhibit excellent heat resistance. In addition, a method for producing such a hollow resin particle in a simple manner is provided. Furthermore, use of such a hollow resin particle is provided. A hollow resin particle according to an embodiment of the present invention is a hollow resin particle including a shell portion and a hollow portion surrounded by the shell portion, wherein the shell portion has an ether structure represented by formula (1).

Abstract: An ester-based elastomer expanded molded article comprising a fusion of expanded particles that contain an ester-based elastomer as a base resin.

Abstract: A thermoplastic resin foam including a thermoplastic resin, wherein: the thermoplastic resin includes a polyester resin and a polyimide resin, and the thermoplastic resin foam shows a single glass transition temperature Tg. The glass transition temperature of the thermoplastic resin is preferably 80 to 130° C. An absolute value of difference between heat absorption and heat generation, each determined by heat flux differential scanning calorimetry at a heating rate of 10° C./min, is preferably 3 to 35 J/g.

Abstract: The present invention provides polymer particles capable of being dissolved in a dissolving medium without generating an unmixed lump and capable of uniformly improving the viscosity of a composition, and a thickener using the polymer particles. The polymer particles of the present invention have a number average particle diameter of 1 to 50 µm and a coefficient of variation in a number-based particle size distribution of 30% or more, wherein where the weight average molecular weight of the whole polymer particles is defined as A, the weight average molecular weight of small particles having a cumulative number percentage of 5% or less counted from the smaller diameter side in the number-based particle size distribution of the polymer particles is defined as B, and the weight average molecular weight of large particles having a particle diameter of 5 times or more the number average particle diameter of the polymer particles is defined as C, polymer particles satisfy the following formulas (1) and (2). 0.

Abstract: Provided is a hollow resin particle that can reduce the dielectricity and dielectric loss tangent of a resin layer by introducing an empty area thereinto, and can be obtained by forming a hollow portion in a simple manner. Also provided is a method of producing such hollow resin particle in a simple manner. A hollow resin particle according to an embodiment of the present invention is a hollow resin particle including a shell portion and a hollow portion surrounded by the shell portion, wherein the shell portion contains an aromatic polymer (P1) obtained by polymerizing a monomer composition containing an aromatic crosslinkable monomer (a), an aromatic monofunctional monomer (b), and a (meth)acrylic acid ester-based monomer (c) having a specific structure.

Abstract: Biodegradable resin particles including a polyhydroxy alkanoate. In the biodegradable resin particles, an amount of a Ca component present in the particles is 10 to 10,000 ppm, the biodegradable resin particles have a volume average particle diameter of 2 to 50 ?m, the biodegradable resin particles have a BET specific surface area of 0.8 to 10 m2/g, and the biodegradable resin particles have a linseed oil absorption of 50 to 300 ml/100 g. The resin particles of the present invention can be suitably used by being included in an external preparation, such as a cosmetic or a quasi-drug.

Abstract: A hydrogel comprising a polymer matrix formed from a copolymer of an acrylic monomer and a crosslinkable monomer, a water-soluble polymer, water, and a polyhydric alcohol, the hydrogel having a tensile strength of 0.5 N/20 mm to 3.0 N/20 mm.

Abstract: An object is to provide fine resin particles that have solvent resistance sufficient to withstand a heating step after solvent dispersion and that generate few bubbles during dispersion and have high dispersibility in a solvent, and a method for producing the fine resin particles. As a solution, fine resin particles obtained by polymerizing a vinyl monomer, the fine resin particles having a gel fraction of 93% or more and a solvent resistance index of 50 or less, and fine resin particles obtained by polymerizing a vinyl monomer, in which the vinyl monomer contains a reactive surfactant having a polyoxyalkylene chain in a molecule thereof, and a vinyl polymer chain of the fine resin particles is terminated with a hydroxy group derived from a polymerization initiator, are provided.

Abstract: An ester-based elastomer expanded molded article comprising a fusion of expanded particles that contain an ester-based elastomer as a base resin.

Abstract: Fluorescent resin particles which comprise a water-soluble fluorescent dye and a polymer made from a monomer mixture.

Abstract: The present invention relates to a method for producing a biodegradable resin expanded sheet, by which a biodegradable resin expanded sheet immediately after extrusion is brought into a predetermined cooled state in an extrusion expansion method, whereby good formability can be exerted.

Abstract: Biodegradable resin particles including a recessed portion in a surface of the particles; and a hollow portion within the particles. The biodegradable resin particles of the present invention can be used in external preparations, such as cosmetics and quasi-drugs; coating materials, such as powder coating compositions and matting agents for coating compositions; rheology modifying agents; anti-blocking agents; smoothing agents; light-diffusing agents; additives for advanced ceramics sintering; fillers for adhesives; and agents for medical diagnosis and examination and can also be used by being added to a resin composition for automotive materials, construction materials, or the like or to a molded product thereof.