The powder adhesive comprises a thermoplastic resin and particles of an aromatic compound, wherein the particles of an aromatic compound are particles of a compound that has an aromatic ring and an azo bond bonded to the aromatic ring, or are particles of a compound comprising a heteroaromatic ring comprising nitrogen atom; the thermoplastic resin comprises an ester group; and, designating Es (mmol/g) as an ester group concentration in the thermoplastic resin, M (mass %) as a content of the aromatic compound particles in the powder adhesive, and N (mmol/g) as a nitrogen atom concentration in the aromatic compound particles, Es is from 1.0 mmol/g to 4.5 mmol/g, M is from 1.0×10.sup.−4 mass % to 1.0×10.sup.0 mass %, and N is from 5.0 mmol/g to 15.0 mmol/g.

The powder adhesive comprises a thermoplastic resin and particles of an aromatic compound, wherein the particles of an aromatic compound are particles of a compound that has an aromatic ring and an azo bond bonded to the aromatic ring, or are particles of a compound comprising a heteroaromatic ring comprising nitrogen atom; the thermoplastic resin comprises an ester group; and, designating Es (mmol/g) as an ester group concentration in the thermoplastic resin, M (mass %) as a content of the aromatic compound particles in the powder adhesive, and N (mmol/g) as a nitrogen atom concentration in the aromatic compound particles, Es is from 1.0 mmol/g to 4.5 mmol/g, M is from 1.0×10.sup.−4 mass % to 1.0×10.sup.0 mass %, and N is from 5.0 mmol/g to 15.0 mmol/g.

Modelling material which includes (a) at least one radically polymerizable monomer, (b) at least one initiator for the radical polymerization and (c) at least one inert component. The inert component (c) is soluble in the polymer formed by polymerization of the monomer (a), wherein the solubility of component (c) decreases as the temperature increases, with the result that a phase separation takes place above a particular temperature. The material is suitable in particular for the production of models of dental restorations for investment casting processes.

The present invention provides a resin composition comprising a thermoplastic resin comprising a constituting unit (A) derived from a compound represented by the following general formula (1), wherein the resin composition comprises an ultraviolet absorber in an amount of 2,000 ppm to 40,000 ppm: ##STR00001##

Provided is a resin composition which makes it possible to improve the resistance to a flux to be used in soldering and the resistance to reflow, and which, when used as a photosensitive resin composition, can be cured into a film capable of being imparted with such thick film processability that the film can be processed with high sensitivity even when the thickness of the film is as high as 15 m or more. A resin composition comprising (A) a resin having a structural unit represented by general formula (1) and/or general formula (2), (B) a phenolic resin and (C) an antioxidant agent, wherein the phenolic resin (B) contains a structure represented by general formula (3).

Provided is a resin composition which makes it possible to improve the resistance to a flux to be used in soldering and the resistance to reflow, and which, when used as a photosensitive resin composition, can be cured into a film capable of being imparted with such thick film processability that the film can be processed with high sensitivity even when the thickness of the film is as high as 15 m or more. A resin composition comprising (A) a resin having a structural unit represented by general formula (1) and/or general formula (2), (B) a phenolic resin and (C) an antioxidant agent, wherein the phenolic resin (B) contains a structure represented by general formula (3).

Modelling material which includes (a) at least one radically polymerizable monomer, (b) at least one initiator for the radical polymerization and (c) at least one inert component. The inert component (c) is soluble in the polymer formed by polymerization of the monomer (a), wherein the solubility of component (c) decreases as the temperature increases, with the result that a phase separation takes place above a particular temperature. The material is suitable in particular for the production of models of dental restorations for investment casting processes.

A photochromic mixture including a photochromic material and a thermosetting transparent polymer material, which are uniformly mixed and dissolved in a solvent, is provided. A formation method of a photochromic device based on the photochromic mixture and a light-transmissive head-mounted display device with the photochromic device are further provided. In the photochromic mixture, the change in the structure of the photochromic material under UV light and room light causes a significant change in its absorption spectrum so the color changes. This property is utilized for the benefits: First, the contrast of the head-mounted display device under strong light irradiation is improved. The display effect is enhanced. Second, the damage to human eye by UV light at the natural environment is reduced. Third, under the same optical requirement, the required energy consumption of self-light-emitting elements in the light-transmissive head-mounted display device is correspondingly reduced. It's more energy saving and environmental protecting.

A photochromic mixture including a photochromic material and a thermosetting transparent polymer material, which are uniformly mixed and dissolved in a solvent, is provided. A formation method of a photochromic device based on the photochromic mixture and a light-transmissive head-mounted display device with the photochromic device are further provided. In the photochromic mixture, the change in the structure of the photochromic material under UV light and room light causes a significant change in its absorption spectrum so the color changes. This property is utilized for the benefits: First, the contrast of the head-mounted display device under strong light irradiation is improved. The display effect is enhanced. Second, the damage to human eye by UV light at the natural environment is reduced. Third, under the same optical requirement, the required energy consumption of self-light-emitting elements in the light-transmissive head-mounted display device is correspondingly reduced. It's more energy saving and environmental protecting.

Provided is an electrically conductive resin composition with which the characteristics inherent in a thermoplastic resin are easily retained and which exhibits more excellent electrical conductivity even if the blending amount of an electrically conductive filler is small. This electrically conductive resin composition contains a thermoplastic resin, such as a polycarbonate or a polyolefin, and an electrically conductive filler, such as a carbon nanotube. This electrically conductive resin composition further contains a dye, such as a perinone-based dye or a disazo-based dye, which is a component for improving electrical conductivity, and this electrically conductive resin composition can be obtained by kneading or molding a raw material mixture containing a thermoplastic resin, an electrically conductive filler, and a dye under a condition of a temperature equal to or higher than the melting point of the thermoplastic resin.