Process for producing silica-based fine particle dispersion sols, silica-based fine particle dispersion sol, coating composition containing the dispersion sol, curable coating film, and substrate having the curable coating film

Patent metadata

Field	Value
Publication number	US-9441139-B2
Application number	US-201514692110-A
Country	US
Kind code	B2
Filing date	Apr 21, 2015
Priority date	Jun 24, 2009
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

Provided are silica-based fine particle dispersion sols, processes for producing the sols, coating compositions containing the dispersion sol, curable coating films obtained from the coating composition, and substrates having the coating film. The process including (1) mixing an aqueous aluminate solution to an alkaline silica sol which contains water-dispersible silica fine particles in a given ratio; (2) heating the mixture liquid obtained in step (1) to 60 to 200° C. and stirring the mixture liquid at the temperature for 0.5 to 20 hours; and (3) contacting the mixture liquid obtained in step (2) with a cation exchange resin to remove by ion exchange alkali metal ions contained in the mixture liquid and thereby controlling the pH of the mixture liquid to be in the range of 3.0 to 6.0.

First claim

The invention claimed is:

1. A coating composition which comprises:
(A) a silica-based fine particle dispersion sol comprising silica-based fine particles having a negative charge on the surface and having a pH in an acidic region from 3.0 to 6.0, wherein the silica-based fine particles are chain particles having an average particle diameter in the range of 5 to 50 nm as calculated by the equation (L+D)/2 wherein L is a longitudinal length and D is a lateral length measured with respect to a transmission electron micrograph, and the surface of the silica-based fine particles, which has been modified with aluminum, comprises a composite oxide of silica-alumina and the amount of the modification by aluminum is in the range of 0.05×10 −6 to 2.0×10 −6 mol/m 2 in terms of Al 2 O 3 per unit surface area of the silica-based fine particle; and
(B) a binder component.

2. The coating composition according to claim 1 , wherein the binder component is an organosilicon compound represented by Formula (II) below and/or a hydrolysate thereof:
R 1 a R 2 b Si(OR 3 ) 4−(a+b)   (II)

(wherein R 1 is a C 1-6 alkyl group, a C 8 or lower organic group having a vinyl group, a C 8 or lower organic group having an epoxy group, a C 8 or lower organic group having a methacryloxy group, a C 1-5 organic group having a mercapto group, or a C 1-5 organic group having an amino group; R 2 is a C 1-3 alkyl, alkylene, cycloalkyl, halogenated alkyl or allyl group; R 3 is a C 1-3 alkyl, alkylene or cycloalkyl group; a is an integer of 0 or 1; and b is an integer of 0, 1 or 2).

3. The coating composition according to claim 1 , wherein the binder component is a thermosetting organic resin or a thermoplastic organic resin.

4. The coating composition according to claim 3 , wherein the thermosetting organic resin is at least one selected from urethane resins, epoxy resins and melamine resins.

5. The coating composition according to claim 3 , wherein the thermoplastic organic resin is at least one selected from acrylic resins, urethane resins and ester resins.

6. The coating composition according to claim 1 , wherein the coating composition is an optical substrate coating composition.

7. The coating composition according to claim 6 , wherein the optical substrate coating composition is a coating composition for forming a hardcoat layer.

8. A curable coating film which is obtained by applying the coating composition described in claim 1 onto a substrate.

9. A substrate having a curable coating film, which is obtained by providing the curable coating film described in claim 8 on a substrate.

Assignees

• Jgc Catalysts & Chemicals Ltd

Inventors

• Ishihara Yoichi
• Nishida Hiroyasu

Classifications

• C09D133/00

  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 title

• C09D183/04 Primary

  Polysiloxanes · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• C09D175/04

  Polyurethanes · CPC title

• C09D183/02

  Polysilicates · CPC title