Sanyo Chemical Industries, Ltd.

Hideaki Saito

Koichi Saito

Yasuhiro Tsudo

Masaki Inaba

Takanori Yamamoto

Masanori Koike

The present invention is urethane resin particles (C) for slush mold which contain a urethane resin (D) and an additive (N), wherein the particles have a shape factor SF1 of 101 to 200, a shape factor SF2 of 120 to 240, and a central particle diameter of 20 to 500 &#x3bc;m. It is preferred that the urethane resin (D) has a concentration of urea groups of 0.5 to 10% by weight, a total of the concentration of urethane groups and that of the urea groups of 4 to 20% by weight, a melting point of 160 to 260&#xb0; C. and a glass transition temperature of &#x2212;65 to 0&#xb0; C.

Process for producing urethane resin particles for slush molding

Provided are urethane resin particles for slush molding which make it possible that inconveniences based on the slip-down of a pigment, on the aggregation of particles of the pigment, and on other causes are removed although this coloring is coloring onto the resin particle surfaces. The present invention is urethane resin particles for slush mold which contain a urethane resin and an additive, wherein the particles have a shape factor SFof 101 to 200, a shape factor SFof 120 to 240, and a central particle diameter of 20 to 500 &#x3bc;m. It is preferred that the urethane resin has a concentration of urea groups of 0.5 to 10% by weight, a total of the concentration of urethane groups and that of the urea groups of 4 to 20% by weight, a melting point of 160 to 260&#xb0; C. and a glass transition temperature of &#x2212;65 to 0&#xb0; C.

Urethane resin particles for slush molding

The object is to develop a resin for a toner, which has both of hot offset resistance and a low-temperature fixing property even when used in a high-speed and energy-saving toner. Thus, disclosed is a resin for a toner, which comprises a polyester resin (A) having a THF insoluble fraction content of 1 to 36 wt %, a peak top molecular weight of 4500 to 20000 as measured by gel permeation chromatography on a THF soluble fraction, and a softening point of 120 to 180&#xb0; C., and meeting the requirements represented by the following formulae (1) and (2):(Acid value)/(hydroxyl value)&#x2267;1 (acid value=15 to 80 mgKOH/g, hydroxyl value&#x2267;3.0 mgKOH/g)&#x2003;&#x2003;Formula (1)(A numeric value of the THF-insoluble fraction content expressed in % by weight)/(a numeric value of the softening point expressed in degree &#xb0; C.)&#x2266;0.2&#x2003;&#x2003;Formula (2).

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Kyoto, Japan

Hideaki Saito