Ciba Specialty Chemicals Corporation

Guo-Hua Hu

Zhimin Hao

Philippe Bugnon

Franck Rey Flandrin

The invention relates to the use of compounds of the formulaR, R, Rand Rindependently of one another are hydrogen, halogen, R, ORor SR, Ris hydrogen or linear or branched C-Calkyl, benzyl or phenethyl, and Ris an apolar group which is unsubstituted or substituted one or more times by halogen or by OC-Calkyl, with the proviso that if Ris hydrogen, R, R, Ror Ris R, ORor SR, as additives in the pigmentation of partially crystalline plastics, especially those processed by injection moulding, with pigments containing at least one each of groupswhich are joined to one another asor are in conjugation with one another. Preferred pigments are quinacridone pigments, disazo condensation pigments, isoindolinone pigments and pyrrolo[3,4-c]pyrrole pigments, especially pyrrolo[3,4-c]pyrrole pigments. Corresponding formulations and novel compounds are likewise claimed. By these means it is possible to avoid warping.

Warp-free pigment compositions comprising diaryldiketopyrrolo[3,4-c]pyrroles

Warp-free pigment compositions comprising diaryldiketopyrrolo&lsqb;3,4-c&rsqb;pyrroles

An injection-molding process using warp-free pigment compositions including diaryldiketopyrrolo&lsqb;3,4-C&rsqb;pyrroles to improve the dimensional stability of the injection molded product by decreasing warping wherein the constituents of the formulation being injection molded are added into an injection molding machine in ready-premixed form or simultaneously as individual components. Preferred pigments are quinacridone pigments, disazo condensation pigments, isoindolinone pigments and pyrrolo&lsqb;3,4-C&rsqb;pyrrole pigments with pyrrolo&lsqb;3,4-C&rsqb;pyrrole pigments being especially preferred.

Injection molding process using warp-free pigment compositions comprising diaryldiketopyrrolo-&lsqb;3,4-c&rsqb;pyrroles to improve dimensional stability

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Nancy, France

Guo-Hua Hu