# US 2019/0169462 A1 · Light-shielding paint, light-shielding paint set, light-shielding film, optical element, method for producing light-shielding film, and method for producing optical element

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- Number: US 2019/0169462 A1
- Document ID: US20190169462A1
- Status: Published application
- Kind: A1
- Application number: 16/265,899
- Filed: 2019-02-01
- Published: 2019-06-06
- Earliest claimed: 2014-08-08
- Assignees: Canon Kabushiki Kaisha
- Applicants: Canon Kabushiki Kaisha
- Inventors: Reiko Kubota; Yoji Teramoto; Shuhei Yamamoto
- Web page: https://patentgrep.com/patent/US20190169462A1

## CPC

- C09D 163/00: Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
- C08G 59/50: Amines
- C08G 59/686: {containing nitrogen}
- G02B 5/003: {Light absorbing elements}
- C08K 3/22: of metals
- C08K 2003/2241: {Titanium dioxide}
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09)

## Abstract

A light-shielding paint includes an epoxy group-containing compound, an inorganic fine particle, a coloring agent, and an amine curing agent. The ratio (A′/A) of the mass (A′) of the amine curing agent to the active hydrogen equivalent (A) of the amine curing agent and the ratio (E′/E) of the mass (E′) of the epoxy group-containing compound to the epoxy equivalent (E) of the epoxy group-containing compound satisfy 0.1≤[(A′/A)/(E′/E)]≤0.45.

## Claims

### Claim 1

A light-shielding film produced from a light-shielding paint that comprises an epoxy group-containing compound, an inorganic fine particle, a coloring agent, and an amine curing agent,
wherein a ratio (A′/A) of a mass (A′) of the amine curing agent to an active hydrogen equivalent (A) of the amine curing agent and a ratio (E′/E) of a mass (E′) of the epoxy group-containing compound to an epoxy equivalent (E) of the epoxy group-containing compound satisfy formula (1) below
0.1≤[(A′/A)/(E′/E)]≤0.45 Formula (1).

### Claim 2 (depends on 1)

The light-shielding film according to claim 1,
wherein the light-shielding paint comprises a curing catalyst.

### Claim 3 (depends on 2)

The light-shielding film according to claim 2,
wherein the curing catalyst is a tertiary amine or an imidazole compound.

### Claim 4 (depends on 1)

The light-shielding film according to claim 1,
wherein the inorganic fine particle has a refractive index of 2.2 or more and 3.5 or less.

### Claim 5

An optical element comprising a light-shielding film disposed on a portion of a base made of an optical material,
wherein the light-shielding film is produced from a light-shielding paint that comprises an epoxy group-containing compound, an inorganic fine particle, a coloring agent, an amine curing agent, and a curing catalyst, and
a ratio (A′/A) of a mass (A′) of the amine curing agent to an active hydrogen equivalent (A) of the amine curing agent and a ratio (E′/E) of a mass (E′) of the epoxy group-containing compound to an epoxy equivalent (E) of the epoxy group-containing compound satisfy formula (1) below
0.1≤[(A′/A)/(E′/E)]≤0.45 Formula (1).

### Claim 6 (depends on 5)

The optical element according to claim 5,
wherein the base is an optical lens or a prism.

### Claim 7

A method for producing a light-shielding film, comprising:
applying, onto a base, a light-shielding paint comprising an epoxy group-containing compound, an inorganic fine particle, a coloring agent, and an amine curing agent; and
curing the applied light-shielding paint in an atmosphere of 20° C. or more and 200° C. or less,
wherein a ratio (A′/A) of a mass (A′) of the amine curing agent to an active hydrogen equivalent (A) of the amine curing agent and a ratio (E′/E) of a mass (E′) of the epoxy group-containing compound to an epoxy equivalent (E) of the epoxy group-containing compound satisfy formula (1) below
0.1≤((A′/A)/(E′/E))≤0.45 Formula (1).

### Claim 8 (depends on 7)

The method according to claim 7,
wherein the light-shielding paint comprises a curing catalyst.

### Claim 9

A method for producing an optical element comprising a light-shielding film disposed on a peripheral surface of a base made of an optical material, the method comprising:
applying, onto the peripheral surface of the base, a light-shielding paint comprising an epoxy group-containing compound, an inorganic fine particle, a coloring agent, and an amine curing agent; and
curing the applied light-shielding paint in an atmosphere of 20° C. or more and 200° C. or less,
wherein a ratio (A′/A) of a mass (A′) of the amine curing agent to an active hydrogen equivalent (A) of the amine curing agent and a ratio (E′/E) of a mass (E′) of the epoxy group-containing compound to an epoxy equivalent (E) of the epoxy group-containing compound satisfy formula (1) below
0.1≤((A′/A)/(E′/E))≤0.45 Formula (1).

### Claim 10 (depends on 9)

The method according to claim 9,
wherein the light-shielding paint comprises a curing catalyst.

### Claim 11 (depends on 10)

The method according to claim 10,
wherein the curing catalyst is a tertiary amine or an imidazole compound.

### Claim 12 (depends on 9)

The method according to claim 9,
wherein the inorganic fine particle has a refractive index of 2.2 or more and 3.5 or less.

### Claim 13 (depends on 1)

An optical device comprising an optical element having the light-shielding film according to claim 1.