Kanzaki Paper Manufacturing Co., Ltd.

Sanko Kaihatsu Kagaku Kenkyusho

Tetsuo Shiraishi

Makoto Miyake

Hiroshi Iwasaki

Tomoharu Shiozaki

Kiyoshi Yasui

Mitsuru Kondo

Toranosuke Saito

Takashi Ishibashi

Shunsuke Shioi

Shoji Aoyagi

Eiji Kawabata

Takao Matsushita

Mitsura Kondo

Shouichi Murata

A developer comprising at least one polyvalent metal salt of a nuclear substituted salicylic acid of the following general formula is provided. ##STR1## In the formula, R.sub.1 represents an alkyl group having from 1 to 12 carbon atoms, R.sub.2 represents a hydrogen atom or an alkyl group having from 1 to 12 carbon atoms, R.sub.3 represents a hydrogen atom or a methyl group provided that at least one of R.sub.1 and R.sub.2 is a secondary butyl group, a secondary hexyl group, an isohexyl group, a secondary octyl group, an isononyl group, a secondary decyl group, a secondary dodecyl group or an isododecyl group and the total number of the carbon atoms in R.sub.1, R.sub.2 and R.sub.3 is from 9 to 18, M is a polyvalent metal atom, and m is a valence of M. An aqueous dispersion containing the developer and a method for preparing the developer are also described.

Developer for pressure-sensitive recording sheets, aqueous dispersion of

An aqueous dispersion of a developer for pressure-sensitive recording sheet, having superior handling performance and storage stability in a high concentration and a process for producing the dispersion are provided, which developer is expressed by the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be the same or different and represent H, halogen, alkyl of 1 to 9 carbon atoms, alkylene, cycloalkyl, cycloalkylene, phenyl, nucleus-substituted phenyl, aralkyl or nucleus-aralkyl; adjacent two of R.sub.1 to R.sub.4 may form a ring; n is an integer of one or more; and M is Mg, Ca, Zn, Al, Fe, Co, Ni or a basic ion of the foregoing, and which developer has a softening point of 30.degree. C. or higher and is dispersed in water, containing a dispersing agent, the size of particles of the developer being 0.3 to 5.mu. in terms of average particle diameter, and the proportion of right spherical particles in the total particles being 50% or more; and which process comprises emulsifying-dispersing the developer in water containing a dispersing agent at a temperature higher by at least 30.degree. C. than the softening point of the developer, follower by cooling, or dissolving the developer in an organic solvent, emulsifying-dispersing the solution in water containing a dispersing agent and distilling off the solvent from the dispersion on heating, or using a polyvinyl alcohol having a polymerization degree of 500 or more and a saponification degree of 70% or more.

Aqueous dispersion of a developer for pressure-sensitive recording sheet

A pressure sensitive manifold paper is prepared with use of microcapsules having enclosed therein an organic solvent, a color former contained in the solvent, and an alkylphenol compound and/or a mercaptan added to the solvent. The paper affords prints resistant to light and has a color forming layer which remains free of coloration and gives prints of original color even when exposed to light.

Pressure sensitive manifold paper

A process is described for preparing triarylmethane derivatives of a high purity in an extremely high yield from 3-phenylphthalide derivatives and aniline derivatives or indole derivatives with Friedel-Crafts type catalyst or Friedel-Crafts type catalyst and an oxidizing agent.

Triarylmethane derivatives

Process for preparing triarylmethane derivatives

The method of making oil-containing microcapsules comprises the steps of (1) preparing an aqueous system comprising an aqueous solution of at least two kinds of hydrophilic colloid materials with opposite electric charges and oil droplets dispersed in said solution (2) causing coacervation in said aqueous system at a temperature above the gelation points of said hydrophilic colloid materials to form a coacervate suspension in which each of said oil droplets is surrounded by a coacervate and (3) cooling said coacervate suspension to a temperature below the gelation points of said hydrophilic colloid materials to form multi-nucleus capsules. During the step of cooling the coacervate suspension, aggregation of particles of oil droplets each having a coacervate therearound is controlled by an agitation flow so as to allow formation of multi-nucleus microcapsules having an average diameter within the range of 3 to 20 microns. Aggregation of particles of oil droplets each having a coacervate therearound is controlled by an agitation flow produced by rotating at least one agitator in a vessel containing the coacervate suspension under the special conditions.

Method of making oil-containing microcapsules

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Hyogo, Japan

Tetsuo Shiraishi