1.
    发明专利
    未知

    公开(公告)号:BR7708795A

    公开(公告)日:1978-08-22

    申请号:BR7708795

    申请日:1977-12-30

    Applicant: HOECHST AG

    Abstract: 2,5-Bis-(4'-aminophenyl)-1,3,4-oxadiazoles which are chlorinated in the phenyl nuclei are obtained by condensing hydrazine or a hydrazine yielding agent with equal or different chlorinated benzoic acids or acylating acid derivatives having in para-position to the acid group an amino group or a group capable of being transformed into the amino group, and, thereafter, effecting ring closure of the so-obtained bis-hydrazide to yield the oxadiazole. The products are bis-diazo components, especially for pigments having a very high tinctorial strength, clear and pure shades, a good fastness to light, to heat and to solvents.

    10.
    发明专利
    未知

    公开(公告)号:BR7600681A

    公开(公告)日:1976-08-31

    申请号:BR7600681

    申请日:1976-02-03

    Applicant: HOECHST AG

    Abstract: N,N'-dimethyl-perylene-3,4,9,10-tetracarboxylic acid diimide is obtained as a valuable pigment of a pure red shade, by reacting perylene-3,4,9,10-tetracarboxylic acid anhydride at low temperatures with a dilute aqueous solution of at least the four-fold molar amount of methylamine. The so-obtained bis-ammonium salt of the bis-N-methyl amide is then heated without isolation to effect ring closure while splitting off two mols of water and two mols of methyl amine. The product can be used without any finish operation or can be after-treated to yield a pigment of an exceptionally high transparency or of a good hiding power.

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