Anticorrosive Coating Compositions

• US 20080000383A1
• Filed: 11/16/2005
• Published: 01/03/2008
• Est. Priority Date: 11/17/2004
• Status: Active Grant

• Current Assignee: DAI Nippon Toryo Company Limited
• Original Assignee: DAI Nippon Toryo Company Limited
• Inventors: Matsuda, Takashi, Matsumoto, Tsuyoshi, Ogawa, Osamu, Nagai, Masanori
• Granted Patent: US 7,658,791 B2
• Time in Patent Office: Days
• US Class Current: 106/14.44
• CPC Class Codes: C09D 5/082 characterised by the anti-corrosive pigment
• CPC Class Codes: C09D 5/084 Inorganic compounds
• CPC Class Codes: C23C 22/23 Condensed phosphates
• CPC Class Codes: C23C 22/74 for obtaining burned-in conversion coatings
• CPC Class Codes: C23C 22/76 Applying the liquid by spraying
• CPC Class Codes: C23F 11/187 Mixtures of inorganic inhibitors

Abstract

It is an object of the present invention to provide an anticorrosive coating composition which uses a pollution-free (heavy metal-free) rust preventive pigment and exhibits anticorrosive performances equal or superior to those of lead compounds or chromic acid compounds even if the pigment is blended in various binder resins and also to provide an anticorrosive coating composition having excellent storage stability. The present invention relates to an anticorrosive coating composition comprising a binder resin and a pollution-free (heavy metal-free) rust preventive pigment containing a condensed calcium phosphate produced by baking a single substance or mixture of a calcium component and a phosphorous component in the following atomic ratio (Ca/P=m): 0.50<m<1.00, at 180 to 350° C.

Claims

1. An anticorrosive coating composition comprising a binder resin and a pollution-free (heavy metal-free) rust preventive pigment containing a condensed calcium phosphate produced by baking a single substance or mixture of a calcium component and a phosphorous component in the following atomic ratio (Ca/P=m):

0.50<

m<

1.00, at 180 to 350°

C.

2. An anticorrosive coating composition according to claim 1, wherein the condensed calcium phosphate is a compound represented by the following formula (1):

Ca_xH_y(P_nO_3n+1)_z 

 

(1)

wherein x denotes a real number from 1 to 4, y denotes a real number from 0 to 2, z denotes a real number from 1 to 2 and n denotes an integer from 2 to 6, provided that 2x+y=(n+2)z.

3. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment further contains an alkali earth metal compound.

4. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment further contains an organic phosphonic acid or a carboxylic acid having a chelating function or its neutralized salt.

5. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment further contains a silane coupling agent.

6. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment is the atomic ratio m of a calcium component to a phosphorous component is in the following range:

0.60<

m<

0.80.

7. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment is characterized in that it is a condensed calcium phosphate selected from the group consisting of CaH₂P₂O₇, Ca₂P₂O₇, Ca₃H₂(P₂O₇)₂, Ca4H₂(P₃O₁₀)₂ and Ca₄P₆O₁₉ and mixtures of these compounds.

8. An anticorrosive coating composition according to claim 1, wherein the pollution-free rust preventive pigment is obtained by baking the mixture at 200 to 290°

C.

9. An anticorrosive coating composition according to claim 1, wherein the condensed calcium phosphate is contained in an amount of 1 to 50 parts by weight based on 100 parts by weight of the solid content of the binder resin.

10. An anticorrosive coating composition according to claim 1, wherein the binder resin is selected from the group consisting of an oil resin, an alkyd resin, a chlorinated rubber resin, an acrylic resin, a polyester resin, an epoxy resin, an epoxy ester resin, a urethane resin, a fluororesin, a moisture-curable polyurethane resin, an acryl modified silicone resin and a butyral resin.