POWDER COATING MATERIAL, METHOD FOR PRODUCING SUBSTRATE PROVIDED WITH COATING FILM, COATED ARTICLE AND FLUORINATED POLYMER

• US 20190322873A1
• Filed: 07/03/2019
• Published: 10/24/2019
• Est. Priority Date: 01/12/2017
• Status: Active Grant

• Current Assignee: AGC, Inc.
• Original Assignee: AGC, Inc.
• Inventors: HASEGAWA, Yui, Hara, Yuji, Sumi, Naoko, Saito, Shun
• Granted Patent: US 11,130,870 B2
• Time in Patent Office: Days
• CPC Class Codes: B05D 7/24 for applying particular liquids or other fluent materials
• CPC Class Codes: B32B 27/30 comprising vinyl (co)polymers; comprising acrylic (co)polymers
• CPC Class Codes: C08F 214/24 Trifluorochloroethene
• CPC Class Codes: C08F 214/245 with non-fluorinated comonomers
• CPC Class Codes: C08F 214/247 with non-fluorinated vinyl ethers
• CPC Class Codes: C08F 216/1416 Monomers containing oxygen in addition to the ether oxygen, e.g. allyl glycidyl ether
• CPC Class Codes: C08F 218/04 Vinyl esters
• CPC Class Codes: C08F 218/08 Vinyl acetate
• CPC Class Codes: C08F 218/10 of monocarboxylic acids containing three or more carbon atoms
• CPC Class Codes: C08F 220/04 Acids; Metal salts or ammonium salts thereof
• CPC Class Codes: C08F 220/64 Acids; Metal salts or ammonium salts thereof
• CPC Class Codes: C08K 5/1515 Three-membered rings
• CPC Class Codes: C08K 5/20 Carboxylic acid amides
• CPC Class Codes: C08L 63/00 Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C09D 127/12 containing fluorine atoms
• CPC Class Codes: C09D 131/02 Homopolymers or copolymers of esters of monocarboxylic acids
• CPC Class Codes: C09D 5/03 Powdery paints

Abstract

To provide a powder coating material capable of forming a coating film excellent in impact resistance, flexibility and adhesion to substrate and excellent in surface smoothness even when formed under low temperature film-forming conditions.

The powder coating material of the present invention is a powder coating material comprising a fluorinated polymer having units based on a fluoroolefin, units based on a monomer represented by the formula X—Z and units based on a monomer represented by the formula CHR²¹═CR²² (CH₂)_nCOOH, wherein the content of the units based on a monomer represented by the formula X—Z is from 5 to 20 mol % to all units in the fluorinated polymer, and the fluorinated polymer has a melt viscosity at 170° C. of from 20 to 100 Pa·s (in the formulae, X is a specific monovalent polymerizable group, Z is a specific alkyl group, a specific cycloalkyl group or a specific aryl group, R²¹ and R²² are each independently a hydrogen atom or a specific alkyl group, and n is an integer of from 0 to 12.

Claims

1. A powder coating material comprising a fluorinated polymer having units based on a fluoroolefin, units based on a monomer represented by the following formula (1) and units based on a monomer represented by the following formula (2),

wherein the content of the units based on a monomer represented by the formula (2) is from 5 to 20 mol % to all units in the fluorinated polymer, and

the fluorinated polymer has a melt viscosity at 170°

C. of from 20 to 100 Pa·

s;

X—

Z 

 

formula (1);

CHR²¹═

CR²²(CH₂)_nCOOH 

 

formula (2);

wherein X is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

,

Z is a C_4-8 alkyl group represented by the formula —

C(Z¹)₃, a C_6-10 cycloalkyl group, a C_6-10 cycloalkylalkyl group, a C_6-10 aryl group or a C_7-12 aralkyl group, provided that three Z¹'"'"'s are each independently a C_1-5 alkyl group, and the total number of carbon atoms of the three Z¹'"'"'s is an integer of from 3 to 7,

R²¹ and R²² are each independently a hydrogen atom or a C_1-3 alkyl group, and

n is an integer of from 0 to 12.

2. The powder coating material according to claim 1, wherein the fluorinated polymer has a glass transition temperature of from 45 to 120°

C.

3. The powder coating material according to claim 1, wherein the fluorinated polymer has a weight average molecular weight of from 15,000 to 75,000.

4. The powder coating material according to claim 1, wherein the content of the units based on a fluoroolefin is from 20 to 60 mol %, and the content of the units based on a monomer represented by the formula (1) is from 5 to 60 mol %, to all units in the fluorinated polymer.

5. The powder coating material according to claim 1, wherein the fluorinated polymer further has units based on a monomer represented by the following formula (3), and the content of the units is more than 0 mol % and at most 40 mol % to all units in the fluorinated polymer:

X³—

Z³ 

 

formula (3);

wherein X³ is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

, and

Z³ is a C_1-3 alkyl group.

6. The powder coating material according to claim 1, wherein the fluorinated polymer contains no units based on a monomer represented by the following formula (4), or contains the units in a content of less than 5 mol % to all units in the fluorinated polymer:

X⁴-Q⁴-OH 

 

formula (4);

wherein X⁴ is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

, and

Q⁴ is a C_2-20 alkylene group which may contain a cyclic structure.

7. The powder coating material according to claim 1, wherein the fluorinated polymer contains no units based on a monomer represented by the following formula (5), or contains the units in a content of less than 8 mol % to all units in the fluorinated polymer:

X⁵—

Z⁵ 

 

formula (5);

wherein X⁵ is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

, and

Z⁵ is an alkyl group having at least 4 carbon atoms, excluding a C_4-8 alkyl group represented by the formula —

C(Z¹)₃,

provided that three Z¹'"'"'s are each independently a C_1-5 alkyl group, and the total number of carbon atoms of the three Z¹'"'"'s is an integer of from 3 to 7.

8. The powder coating material according to claim 1, which further contains a curing agent comprising a compound having in one molecule at least two epoxy groups, carbodiimide groups, oxazoline groups or p-hydroxyalkylamide groups.

9. The powder coating material according to claim 8, wherein the content of the curing agent is from 1 to 50 mass % to the fluorinated polymer.

10. The powder coating material according to claim 8, which is constituted by particles containing the fluorinated polymer and the curing agent.

11. A method for producing a substrate provided with a coating film, which comprises applying the powder coating material as defined in claim 1 to a substrate to form a powder coating material layer, and subjecting the powder coating material layer to heat treatment to form a coating film on the substrate.

12. A coated article comprising a substrate and a coating film formed from the powder coating material as defined in claim 1 on the substrate.

13. A fluorinated polymer having units based on a fluoroolefin, units based on a monomer represented by the following formula (1) and units based on a monomer represented by the following formula (2),

wherein the content of the units based on a monomer represented by the formula (2) is from 5 to 20 mol % to all units in the fluorinated polymer, and

the fluorinated polymer has a weight average molecular weight of from 15,000 to 75,000:

X—

Z 

 

formula (1);

CHR²¹═

CR²²(CH₂)_nCOOH 

 

formula (2);

wherein X is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

,

Z is a C_4-8 alkyl group represented by the formula —

C(Z¹)₃, a C_6-10 cycloalkyl group, a C_6-10 cycloalkylalkyl group, a C_6-10 aryl group or a C_7-12 aralkyl group, provided that three Z¹'"'"'s are each independently a C_1-5 alkyl group, and the total number of carbon atoms of the three Z¹'"'"'s is an integer of from 3 to 7,

R²¹ and R²² are each independently a hydrogen atom or a C_1-3 alkyl group, and

n is an integer of from 0 to 12.

14. A fluorinated polymer having units based on a fluoroolefin, units based on a monomer represented by the following formula (1) and units based on a monomer represented by the following formula (2),

wherein the content of the units based on a monomer represented by the formula (2) is from 5 to 20 mol % to all units in the fluorinated polymer, and

the fluorinated polymer has a melt viscosity at 170°

C. of from 20 to 100 Pa·

s;

X—

Z 

 

formula (1);

CHR²¹═

CR²²(CH₂)_nCOOH 

 

formula (2);

wherein X is CH₂═

CHC(O)O—

, CH₂═

C(CH₃)C(O)O—

, CH₂═

CHOC(O)—

, CH₂═

CHCH₂OC(O)—

, CH₂═

CHO—

or CH₂═

CHCH₂O—

,

Z is a C_4-8 alkyl group represented by the formula —

C(Z¹)₃, a C_6-10 cycloalkyl group, a C_6-10 cycloalkylalkyl group, a C_6-10 aryl group or a C_7-12 aralkyl group, provided that three Z¹'"'"'s are each independently a C_1-5 alkyl group, and the total number of carbon atoms of the three Z¹'"'"'s is an integer of from 3 to 7,

R²¹ and R²² are each independently a hydrogen atom or a C_1-3 alkyl group, and

n is an integer of from 0 to 12.