Coating composition

• US 20030073778A1
• Filed: 10/01/2002
• Published: 04/17/2003
• Est. Priority Date: 10/01/2001
• Status: Active Grant

• Current Assignee: Rohm and Haas Company (Dow, Inc.)
• Original Assignee: Rohm and Haas Company (Dow, Inc.)
• Inventors: Zhang, Wei, Pressley, Ozzie Moore
• Granted Patent: US 6,818,697 B2
• Time in Patent Office: Days
• US Class Current: 524/555
• CPC Class Codes: C08F 265/04 on to polymers of esters
• CPC Class Codes: C08F 265/06 Polymerisation of acrylate or methacrylate esters on to polymers thereof
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/24 Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C09D 133/00 Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 151/003 grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C09D151/04, C09D151/06 take precedence

Abstract

An improved aqueous coating composition which includes a bimodal copolymer. Methods of using an aqueous coating composition which includes a bimodal copolymer.

Claims

1. A coating composition comprising a bimodal aqueous emulsion copolymer, wherein said bimodal copolymer comprises as polymerized units from 0.1% to 10% by weight, based on the dry weight of said copolymer, of a compound selected from the group consisting of at least one strong acid monomer, and salts thereof;

wherein said copolymer comprises small mode particles having a diameter of from 50 to 150 nm;

wherein said copolymer comprises large mode particles having a diameter of less than 400 nm, and said large mode particles are larger in diameter than said small mode particles; and

wherein the ratio of said small mode particles to said large mode particles is from 10;

90 to 90;

10 by weight.

2. The composition, according to claim 1, wherein said strong acid monomer comprises from 0.5% to 10% by weight, of a phosphorous containing monomer.

3. The composition, according to in claim 1, wherein said ratio of said small mode particles to said large mode particles is from 30:

70 to 80;

20 by weight.

4. The composition, according to claim 1, wherein said copolymer is prepared by a one-pot process.

5. The composition, according to claim 1, wherein at least one mode of said copolymer is prepared by a multi-stage process.

6. The composition, according to claim 1, wherein said composition further comprises a pigment, wherein said pigment comprises at least one multivalent metal ion.

7. A method for blocking stains on a substrate comprising:

(a) forming a coating composition comprising a bimodal aqueous emulsion copolymer,

wherein said copolymer comprises as polymerized units from 0.1% to 10% by weight, based on the dry weight of said copolymer, of a compound selected from the group consisting of at least one strong acid monomer, and salts thereof;

wherein said copolymer contains small mode particles having a diameter of from 50 to 150 nm;

wherein said copolymer contains large mode particles having a diameter of less than 400 nm, and said large mode particles are larger in diameter than said small mode particles;

wherein the ratio of said small mode particles to said large mode particles is from 10;

90 to 90;

10;

(b) applying said coating composition to a substrate; and

(c) drying, or allowing to dry said coating composition.

8. A method for providing improved hiding comprising:

(a) forming a coating composition comprising a bimodal aqueous emulsion copolymer,

wherein said copolymer comprises as polymerized units from 0.1% to 10% by weight, based on the dry weight of said copolymer of a compound selected from the group consisting of at least one strong acid monomer, and salts thereof;

wherein said copolymer contains small mode particles having a diameter of from 50 to 150 nm;

wherein said copolymer contains large mode particles having a diameter of less than 400 nm, and said large mode particles are larger in diameter than said small mode particles;

wherein the ratio of said small mode particles to said large mode particles is from 10;

90 to 90;

10;

(b) applying said coating composition to a substrate; and

(c) drying, or allowing to dry said coating composition.

9. A method for providing improved block resistance comprising:

(a) forming a coating composition comprising a bimodal aqueous emulsion copolymer,

wherein said copolymer comprises as polymerized units from 0.1% to 10% by weight, based on the dry weight of said copolymer, of a compound selected from the group consisting of at least one strong acid monomer, and salts thereof;

wherein said copolymer contains small mode particles having a diameter of from 50 to 150 nm,

wherein said copolymer contains large mode particles having a diameter of less than 400 nm, and said large mode particles are larger in diameter than said small mode particles;

wherein the ratio of said small mode particles to said large mode particles is from 10;

90 to 90;

10;

(b) applying said coating composition to a substrate; and

(c) drying, or allowing to dry said coating composition.

10. A method for providing improved shear stability comprising, forming a coating composition comprising a bimodal aqueous emulsion copolymer,

wherein said copolymer comprises as polymerized units from 0.1% to 10% by weight, based on the dry weight of said copolymer, of a compound selected from the group consisting of at least one strong acid monomer, and salts thereof;

wherein said copolymer contains small mode particles having a diameter of from 50 to 150 nm;

wherein said copolymer contains large mode particles having a diameter of less than 400 nm, and said large mode particles are larger in diameter than said small mode particles; and

wherein the ratio of said small mode particles to said large mode particles is from 10;

90 to 90;

10.