Basf Aktiengesellschaft

Peter Hauser

Gerhard Wagenblast

Peter Neumann

Erwin Hahn

Wolfgang Schrott

Volker Radtke

Manfred Patsch

Bernhard Albert

Helmut Barzynski

Georg Henning

Klaus D Schomann

Harald Kuppelmaier

Matthias Dust

Manfred Mielke

Michael Acker

Heinrich Kowarsch

Heidi Benthack-Thoms

Manfred Maier

A stationary container equipped with an inlet and an outlet and filled with grinding medium encloses a drivable, rotatably mounted stirrer whose active surfaces are formed as impellers for the grinding medium which are closely adjacent to the inner surface of the container.

Stirred ball mill for grinding pigments

An optical recording medium contains a transparent base, a dye-containing layer which is sensitive to laser light and a reflector layer which contains a silicon-phthalocyanine derivative of the formula ##STR1## where R.sup.1 is hydrogen, alkyl, alkoxy, halogen or trialkylsilyl, n is 1, 2, 3 or 4 and A and B are identical or different and independently of one another are each alkyl, halogen or unsubstituted or substituted alkoxy or trialkylsilyloxy.

Optical recording medium which has a reflector layer containing a

A tetrachloroperylene-3,4,9,10-tetracarboxylic acid diimide pigment which contains not less than 85% by weight of the tetrachloro compound of the formula ##STR1## which is present to the extent of not less than 95% by weight in the .beta.-modification and which, in an X-ray spectrum, exhibits 2.sup..crclbar. CuK.sub..alpha. main lines at 9.0.degree., 13.3.degree., 15.0.degree., 16.8.degree., 19.1.degree., 21.5.degree., 24.2.degree., 25.4.degree., 26.5.degree., 27.0.degree. and 27.5.degree.. In finishes, the pigment gives very brilliant colorations which are very highly lightfast and fast to weathering and which, upon weathering, neither bleach nor darken up.

Tetrachloroperylene-3,4,9,10-tetracarboxylic acid diimide pigment and

Naphtholactamsquaric acid dyes of the formula ##STR1## where R.sup.1 and R.sup.2 independently of one another are each unsubstituted or substituted C.sub.3 -C.sub.22 -alkyl, in which the alkyl chain may be interrupted by oxygen atoms, or are each unsubstituted or substituted C.sub.1 -C.sub.4 -aralkyl, unsubstituted or substituted C.sub.5 -C.sub.7 -cycloalkyl or unsubsituted or substituted phenyl, and the rings A, B, C and D are unsubstituted or substituted and/or benzofused, and optical recording materials consisting of a base and a layer which is sensitive to laser light and is composed of a thermoplastic or crosslinked polymer and one or more dyes (I). Because of the high light absorption of (I), the recording materials are very sensitive to light from the GaAlAs semiconductor laser. An excellent signal-to-noise ratio is obtained on reading the recordings.

Naphtholactamsquaric acid dyes and optical recording materials

An optical recording medium containing a storage layer and, if required, one or two substrate layers, the storage layer containing graphite as the storage material, a process for the production of the novel optical recording medium, and its use as a Read Only Memory information carrier.

Optical recording medium, its preparation and its use as a read only

Finely divided, transparent, metal-free X-phthalocyanine has a specific surface area of from 75 to 120 m.sup.2 g and not less than 80% by weight of the phthalocyanine particles have a Stokes-equivalent diameter of .ltoreq.0.12 .mu.m. The phthalocyanine is very useful as a pigment for printing inks and finishes.

Finely divided transparent metal-free X-phthalocyanine

A compound having the formula (I): ##STR1## wherein D is a radical of a heterocyclic or aromatic component selected from the group of aniline, anthraquinone, phthalimide or aminobenzene radicals, wherein the radical is unsubstituted or is substituted by fluorine, chlorine, bromine, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, trifluoromethyl, cyano, C.sub.1 -C.sub.4 -alkylsulfonyl, carboxylic acid ester groups, carbamyl, sulfamyl, 1,3,4- or 1,2,4-oxadiazolyl or acylamino groups; X is CO-- or --SO.sub.2 --; and R is an aliphatic, aromatic or heterocyclic radical selected from the group of C.sub.1 -C.sub.20 alkyl which is unsubstituted or is substituted by chlorine, bromine, cyano or dialkylamino groups; or phenyl or methyl groups unsubstituted or substituted by fluorine, bromine, methyl, ethyl, methoxy, ethoxy, cyano, carbamyl, sulfamyl or acylamino groups; or amino group; or a radical of the formula: ##STR2## wherein ring a is unsubstituted or is substituted by nitro, fluro, bromine or methoxy groups; and ring b is unsubstituted or is substituted by chlorine, bromine or nitro groups. The majority of the compounds of the formula (I) have yellow hues and are used as pigments in printing inks and finishes, and as disperse dyes for synthetic fibers.

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Peter Hauser