Process for producing pyrophosphate

Patent metadata

Field	Value
Publication number	US-9493353-B2
Application number	US-201414652797-A
Country	US
Kind code	B2
Filing date	Feb 14, 2014
Priority date	Mar 1, 2013
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

A process for producing a pyrophosphate, particularly melamine pyrophosphate useful as a flame retardant, efficiently in high yield is provided. The process includes firing an orthophosphate, preferably melamine orthophosphate, in the presence of a silicone oil, preferably methylphenyl silicone oil preferably at 120° to 350° C. Examples of useful firing equipment include a hot air dryer, a kneader, a Henschel mixture, a fluidized bed dryer, a rotary kiln, a paddle dryer, an extruder, a vibrating dryer, a far-infrared conveyor furnace, and a microwave firing furnace.

First claim

The invention claimed is:

1. A process for producing a pyrophosphate comprising firing an orthophosphate in the presence of a silicone oil, the pyrophosphate being selected from the group consisting of ammonium pyrophosphate, melamine pyrophosphate, acetoguanamine pyrophosphate, benzoguanamine pyrophosphate, acrylguanamine pyrophosphate, 2,4-diamino-6-nonyl-1,3,5-triazine pyrophosphate, 2,4-diamino-6-hydroxy-1,3,5-triazine pyrophosphate, 2-amino-4,6-dihydroxy-1,3,5-triazine pyrophosphate, 2,4-diamino-6-methoxy-1,3,5-triazine pyrophosphate, 2,4-diamino-6-ethoxy-1,3,5-triazine pyrophosphate, 2,4-diamino-6-propoxy-1,3,5-triazine pyrophosphate, 2,4-diamino-6-isopropoxy-1,3,5-triazine pyrophosphate, 2,4-diamino-6-mercapto-1,3,5-triazine pyrophosphate, 2-amino-4,6-dimercapto-1,3,5-triazine pyrophosphate, N,N,N′,N′-tetramethyldiaminomethane pyrophosphate, ethylenediamine pyrophosphate, N,N′-dimethylethylenediamine pyrophosphate, N,N′-diethylethylenediamine pyrophosphate, N,N-dimethylethylenediamine pyrophosphate, N,N-diethylethylenediamihne pyrophosphate, N,N,N′,N′-tetramethylethylenediamine pyrophosphate, 1,2-propanediamine pyrophosphate, 1,3-propanediamine pyrophosphate, tetramethylenediamine pyrophosphate, pentametylenediamine pyrophosphate, hexamethylenediamine pyrophosphate, 1,7-diaminoheptane pyrophosphate, 1,8-diaminooctane pyrophosphate, 1,9-diaminononane pyrophosphate, 1,10-diaminodecane pyrophosphate, piperazine pyrophosphate, trans-2,5-dimethylpiperazine pyrophosphate, 1,4-bis(2-aminoethyl)piperazine pyrophosphate, and 1,4-bis(3-aminopropyl)piperazine pyrophosphate.

2. The process according to claim 1 , wherein the orthophosphate is melamine orthophosphate and the pyrophosphate is melamine pyrophosphate.

3. The process according to claim 1 , wherein the silicone oil is methylphenyl silicone oil.

4. The process according to claim 1 , wherein the firing is at a temperature of 120° to 350° C.

5. The process according to claim 2 , wherein the silicone oil is methylphenyl silicone oil.

6. The process according to claim 2 , wherein the firing is at a temperature of 120° to 350° C.

7. The process according to claim 3 , wherein the firing is at a temperature of 120° to 350° C.

8. The process according to claim 5 , wherein the firing is at a temperature of 120° to 350° C.

9. A process for producing melamine pyrophosphate comprising firing melamine orthophosphate in the presence of a silicone oil.

10. The process according to claim 9 , wherein the silicone oil is methylphenyl silicone oil.

11. The process according to claim 9 , wherein the firing is at a temperature of 120° to 350° C.

12. The process according to claim 10 , wherein the firing is at a temperature of 120° to 350° C.

13. The process according to claim 1 , wherein the firing temperature is 150° to 300° C.

14. The process according to claim 1 , wherein the firing temperature is 160° to 280° C.

15. The process according to claim 9 , wherein the firing temperature is 150° to 300° C.

16. The process according to claim 9 , wherein the firing temperature is 160° to 280° C.

Assignees

• Adeka Corp

Inventors

• Harada Genta
• Yonezawa Yutaka
• Nakamura Michio
• Okamoto Yuri
• Omori Kohei

Classifications

• C07D295/02

  containing only hydrogen and carbon atoms in addition to the ring hetero elements · CPC title

• C01B25/42 Primary

  Pyrophosphates · CPC title

• C07F9/6509

  Six-membered rings · CPC title

• C07D251/54

  Three nitrogen atoms · CPC title