Abstract: The present invention provides a urethane resin composition including a urethane resin that is a product of reaction of at least one polyol (A) including a polycarbonate polyol (a1) with a polyisocyanate (B), in which the polycarbonate polyol (a1) is a compound produced using, as a raw material, at least one hydroxy compound (C) including a hydroxy compound (c1) represented by general formula (1) below. The urethane resin composition is capable of forming a urethane resin-molded article having high solvent resistance and high hydrolysis resistance.

Abstract: An active-energy-ray-curable hot-melt urethane resin composition contains a hot-melt urethane and an active energy ray polymerization initiator, the hot-melt urethane being obtained by converting more than 50% and 100% or less of the total number of isocyanate groups in an isocyanate group-terminated urethane prepolymer into terminal (meth)acryloyl groups by a reaction with hydroxyl groups in a reactive functional group-containing (meth)acrylic compound, the isocyanate group-terminated urethane prepolymer being obtained by reacting a polyisocyanate component with a polyol component that contains an aromatic polyester polyol containing a 2,2-dimethyl-1,3-propylene structure in its molecule in an amount of 90% by mole or more of a glycol component and a polyol other than the aromatic polyester polyol.

Abstract: A radical-curable hot-melt urethane resin composition includes 100 parts by mass of a hot-melt urethane (X) having a (meth)acryloyl group and 0.5 to 5.0 parts by mass of a radical polymerization initiator (Y), wherein the hot-melt urethane (X) is obtained by introducing, using a (meth)acrylate compound (D) having an active-hydrogen-containing group, a (meth)acryloyl group into a hot-melt urethane prepolymer (C) that has isocyanate groups at its terminals and is obtained by a reaction of a polyol (A) and an alicyclic polyisocyanate (B), the polyol (A) containing an aliphatic polycarbonate polyol (a1), an alicyclic polycarbonate polyol (a2), or an aliphatic polyether polyol (a3), in an amount of more than 50 mol % and 100 mol % or less of the total number of isocyanate groups of the urethane prepolymer (C).

Abstract: A radical-curable hot-melt urethane resin composition includes 100 parts by mass of a hot-melt urethane (X) having a (meth)acryloyl group and 0.5 to 5.0 parts by mass of a radical polymerization initiator (Y), wherein the hot-melt urethane (X) is obtained by introducing, using a (meth)acrylate compound (D) having an active-hydrogen-containing group, a (meth)acryloyl group into a hot-melt urethane prepolymer (C) that has isocyanate groups at its terminals and is obtained by a reaction of a polyol (A) and an alicyclic polyisocyanate (B), the polyol (A) containing an aliphatic polycarbonate polyol (a1), an alicyclic polycarbonate polyol (a2), or an aliphatic polyether polyol (a3), in an amount of more than 50 mol % and 100 mol % or less of the total number of isocyanate groups of the urethane prepolymer (C).

Abstract: An active-energy-ray-curable hot-melt urethane resin composition contains a hot-melt urethane and an active energy ray polymerization initiator, the hot-melt urethane being obtained by converting more than 50% and 100% or less of the total number of isocyanate groups in an isocyanate group-terminated urethane prepolymer into terminal (meth)acryloyl groups by a reaction with hydroxyl groups in a reactive functional group-containing (meth)acrylic compound, the isocyanate group-terminated urethane prepolymer being obtained by reacting a polyisocyanate component with a polyol component that contains an aromatic polyester polyol containing a 2,2-dimethyl-1,3-propylene structure in its molecule in an amount of 90% by mole or more of a glycol component and a polyol other than the aromatic polyester polyol.

Abstract: A device for detecting and controlling developing agent toner density includes a rotating magnet for forming a magnetic brush of developing agent and an electrically conductive glass plate for separating the toner from the carrier so that the density of the toner can be optically measured and used to control the addition of toner to the developing agent.

Abstract: A magnetic brush developing device for a xerographic copying machine is constructed to prevent toner from being leaked out of the developer housing. A magnetic brush roll is provided opposite to a photosensitive member, and at least one air current blade is provided along the lower outer periphery of the surface of the magnetic brush roll. One end of the air current blade is closely adjacent the surface of the photosensitive member, and the other end of the air current blade projects back toward the interior of the developer housing. An air circulating path is defined between the air current blade and the lower outer wall of the developer housing. This air circulating path is effective to conduct entrained air carrying excess toner back into the developer housing.

Abstract: A development apparatus in which particles stored in a chamber of a housing are deposited on a latent image. Air flow is controlled to prevent leakage of the particles from the chamber of the housing.