Production of metal-containing azo dyestuffs

• US 2,856,397 A
• Filed: 10/07/1953
• Issued: 10/14/1958
• Est. Priority Date: 10/09/1952
• Status: Expired due to Term

• Current Assignee: Helmut Pfitzner, Otto Kaufmann
• Original Assignee: Helmut Pfitzner, Otto Kaufmann
• Inventors: HELMUT PFITZNER, Kaufmann, Otto
• Application Number:
  US03/384,764
• Time in Patent Office: 1,833 Days
• US Class Current: 534/588
• CPC Class Codes: C09B 45/14 Monoazo compounds

Claims

1. IN A PROCESS FOR THE PRODUCTION OF A METAL COMPLEX COMPOUND OF A MONOAZO DYESTUFF BY REACTION OF A METALFREE MONOAZO DYESTUFF OF THE GROUP CONSISTING OF O.O'"'"''"'"'-DIHYDROXY, O-METHOXY-O'"'"''"'"'-HYDROXY AND O-CARBOXY-O'"'"''"'"'-HYDROXY MONOAZO COMPOUNDS CONTAINING A SULFONIC ACID GROUP IN PARA-POSITION TO A HYDROXY GROUP WITH A COMPLEX FORMING METAL SALT WHEREIN THE METAL IS BOUND IN COMPLEX COMBINATION WITH SAID MONOAZO DYESTUFF WHILE SPLITTING OFF SAID SULFONIC ACID GROUP IN PARA-POSITION TO HYDROXY GROUP, THE IMPROVEMENT WHICH COMPRISES:

HEATING SAID METAL-FREE MONOAZO DYESTUFF TOGETHER WITH SAID COMPLEX FORMING METAL SALT IN A REACTION MEDIA CONSISTING ESSENTIALLY OF A POLYHYDRIC ALCOHOL AT ABOUT 100*C. TO 150*C., SAID POLYHYDRIC ALCOHOL ACTING TO SPLIT OFF A SULFONIC ACID GROUP IN PARA-POSITION TO A HYDROXY GROUP.