Ciba-geigy Corporation

Ciba Specialty Chemicals Corporation

Basf Aktiengesellschaft

Japat Limited

Jin Mizuguchi

Alain C Rochat

Abul Iqbal

Gerald Giller

Olof Wallquist

Zhimin Hao

Remy Jeanneret

Nobuya Shimo

Walter Fischer

Edward E Jaffe

Peter Erk

Marcus Baumann

Beat Schmidhalter

John S Zambounis

Annemarie Wolleb

Arno Boehm

Andreas Stohr

Walter Kurtz

Heinz Spahni

Jurgen Vogt

Jean-Luc Budry

Hiroshi Yamamoto

Benno Sens

G&eacute;rald Giller

Seiji Homma

Takashi Deno

Hanspeter Stricker

Black perylene pigments which comprise one of the isomers of the formula Ia or Ib in which

Black perylene pigments

A black perylene-based pigment produced by calcining at least one compound selected from the group consisting of diimide derivatives of perylene tetracarboxylic acid and diimide derivatives of perylene diiminodicarboxylic acid, at a temperature of 200 to 600&#xb0; C. in vacuum or in an inert gas atmosphere, exhibits an excellent blackness, an excellent heat resistance and an excellent weather fastness as well as a high resistance and a high safety.

Black perylene pigment and process for producing the same

A black perylene-based pigment comprising a solid solution obtained by calcining a mixture of at least two compounds selected from the group consisting of anhydrides of perylene tetracarboxylic acid, diimide derivatives of perylene tetracarboxylic acid and diimide derivatives of perylene diiminodicarboxylic acid, exhibits an excellent blackness, an excellent heat resistance and an excellent weather fastness as well as a high resistance and a high safety.

Black perylene-based pigment and process for producing the same

The invention relates to an optical storage medium comprising a substrate and a storage layer, wherein the storage layer comprises a compound of the formula (I) or (II)

Writable and erasable high-density optical storage media

A process for the preparation of compounds of formula I ##STR1## by reacting a pyrrolopyrrole of formula ##STR2## wherein X.sub.1 is a group selected from ##STR3## X.sub.2 is a group selected from ##STR4## or has the same meaning as X.sub.1, with a secondary amine of formula ##STR5## in the molar ratio 1:2, in the presence of an anhydrous dipolar aprotic solvent and of an amount 0.1 to 15 times in excess of stoichiometric proportion, based on the amine of formula III, of an anhydrous organic base, in the temperature range from 50.degree. to 230.degree. C. and under a pressure from 0 to 10 bar. The substituents R.sub.1 to R.sub.8, Y and Hal are as defined in claim 1. The compounds of formula I are especially suitable for use as photoconductive substances.

Process for the preparation of aminated diketobis (aryl or

A process for the preparation of mixed crystals of 1,4-diketopyrrolo�3,4-c!pyrroles, consisting of 1 mol each of two different compounds of formula ##STR1## by heating a corresponding mixture in solid form to the temperature range from 220.degree. to 380.degree. C.

Preparation of mixed crystals and solid solutions of

Mono-N-alkyl-quinacridone pigments

A process for the preparation of mixed crystals of 1,4-diketopyrrolo�3,4-c!pyrroles, consisting of 1 mol each of two different compounds of formula ##STR1## by heating a corresponding mixture in solid form to the temperature range from 220.degree. to 380.degree. C. A and B are, for example, each a group of formula ##STR2## wherein R.sub.1 and R.sub.2 are each independently hydrogen, chloro, bromo, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylamino, phenyl or --CN, G is --O--, --NR.sub.7 --, --N.dbd.N-- or --SO.sub.2 --, R.sub.3 and R.sub.4 are hydrogen, and R.sub.7 is hydrogen, methyl or ethyl. The mixed crystals and solid solutions obtained are excellently suited for pigmenting high molecular weight material.

Preparation of mixed crystals and solid solutions of 1,

A process for the optical recording and storage of information in the form of bits by irradiating a recording material comprising a substrate coated with at least one layer of a pigment selected from the group of the dithiopyrrolopyrroles, dithioquinacridones, phthalocyanines or mixtures of several of these pigments as recording layer dotwise or linearly with laser light in the near infrared range (NIR range), which pigment (a) has a crystal modification having an absorption band in the NIR range, and (b) is in contact with a solid organic compound that changes the crystal modification of the pigment upon irradiation with laser light, so that (c) after irradiation the absorption in the NIR range is reduced, while the organic compound exhibits no absorption in the NIR range before and after irradiation.

Material for storing information

A coated material comprising a substrate which is coated with a layer of a pyrrolopyrrole of formula I ##STR1## wherein R.sub.1 and R.sub.2 may be 4-pyridyl and X.sub.1 and X.sub.2 are O, said compound of formula I being at least partially in the form of a salt of a strong acid, is suitable for use as an optical recording material and, owing to its electrical conductivity and photoconductivity, as antistatically treated material, as sensor, photoreceptor and solar battery.

Process for storing information and a material having information

Process for storing information

A process for storing information in an organic recording layer which, when treated locally with an organic solvent in accordance with the input of information, is able to change its absorption spectrum and/or its photoconductivity such that information can be produced or stored at the treated areas of said layer, wherein the organic solvent is solid at room temperature and is present in the recording layer, or by decomposition of a solid organic precursor which is present in the recording layer, and said solvent is vaporized or melts by the action of laser beams in accordance with the input of information, or said precursor is decomposed by the action of laser beams in accordance with the input of information. The stored information can be read out with a photodetector in the visible or near NIR range or with a built-in electrode system.

Process for storing information with high storage density

Coated material and the use thereof

Novel electrochromic compositions based on diketopyrrolopyrroles

Compounds of the formula I ##STR1## in which R is the group --OC.sub.m H.sub.2mn R.sub.1 and M is two H or is Cu or Ni, R.sub.1 is --OH, --Cl, --Br, C.sub.1 -C.sub.30 alkoxy or --OC(O)R.sub.2, m is an integer from 2 to 6 and n is a number from 1 to 20, and R.sub.2 is C.sub.1 -C.sub.20 alkyl, C.sub.2 -C.sub.20 alkenyl, cyclopentyl, cyclohexyl or C.sub.6 -C.sub.10 aryl or C.sub.6 -C.sub.10 arylmethyl which is unsubstituted or substituted by C.sub.1 -C.sub.18 alkyl. The compounds are dyes and IR absorbers and can be used for optical information storage systems employing diode lasers.

Substituted naphthalocyanines and their use

Growing community of inventors

Fribourg, Switzerland

Jin Mizuguchi