Layered sheet, electronic component packaging container, and electronic component packaging

Patent metadata

Field	Value
Publication number	US-11701874-B2
Application number	US-202017604341-A
Country	US
Kind code	B2
Filing date	Apr 16, 2020
Priority date	Apr 26, 2019
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A layered sheet has a substrate layer and surface layers provided on both surfaces of the substrate layer, wherein the surface layers contain 50 to 90 mass % of component (A) defined below and 10 to 50 mass % of component (B) defined below relative to the overall mass of the surface layer; the substrate layer is composed of a vinyl aromatic hydrocarbon resin composition containing monomer units derived from conjugated dienes; and a percentage of the monomer units derived from the conjugated dienes in the substrate layer is 6 to 14 mass % relative to all monomer units in the vinyl aromatic hydrocarbon-based resin composition. Component (A) is a rubber-modified (meth)acrylic acid ester-vinyl aromatic hydrocarbon copolymer in which the percentage of a conjugated diene rubber component is 5 to 25 mass %. Component (B) is a polymeric antistatic agent.

First claim

The invention claimed is:

1. A layered sheet having a substrate layer and surface layers provided on both surfaces of the substrate layer, wherein:
the surface layers contain 50 to 90 mass % of component (A) defined below and 10 to 50 mass % of component (B) defined below relative to the overall mass of the surface layer;
the substrate layer is composed of a vinyl aromatic hydrocarbon-based resin composition containing monomer units derived from conjugated dienes; and
a percentage of the monomer units derived from the conjugated dienes in the substrate layer is 6 to 14 mass % relative to all monomer units in the vinyl aromatic hydrocarbon-based resin composition;
the vinyl aromatic hydrocarbon-based resin composition contains 30 to 70 mass % of component (C) defined below, 30 to 70 mass % of component (D) defined below, and 0 to 40 mass % of recycled layered sheet material relative to the overall mass of the vinyl aromatic hydrocarbon-based resin composition;
component (A) being a rubber-modified (meth)acrylic acid ester-vinyl aromatic hydrocarbon copolymer in which a percentage of a conjugated diene rubber component is 5 to 25 mass %;
component (B) being a polymeric antistatic agent,
component (C) being a vinyl aromatic hydrocarbon-conjugated diene block copolymer; and
component (D) being at least one polymer selected from the group consisting of vinyl aromatic hydrocarbon polymers and rubber-modified vinyl aromatic hydrocarbon polymers.

2. The layered sheet according to claim 1 , wherein the polymeric antistatic agent is a block copolymer having, in a molecular chain, a hydrophilic block and at least one block selected from the group consisting of polyolefin-based blocks and polyamide-based blocks.

3. The layered sheet according to claim 1 , wherein the thickness ratio between the layers in the layered sheet, represented by surface layer/substrate layer, is 10/90 to 50/50.

4. The layered sheet according to claim 1 , wherein the layered sheet has an image clarity, as measured by a measurement method in accordance with the JIS-K-7374 standard, of 40% or higher.

5. The layered sheet according to claim 1 , wherein the layered sheet has a tensile modulus, as measured by a measurement method in accordance with the JIS-K-7127 standard, of 1200 to 2000 MPa.

6. The layered sheet according to claim 1 , wherein the layered sheet has a folding endurance, as measured by a measurement method in accordance with the JIS-P-8115 standard, of 30 times or more.

7. The layered sheet according to claim 1 , wherein a punching burr formation rate is less than 10%.

8. An electronic component packaging container using the layered sheet according to claim 1 .

9. The electronic component packaging container according to claim 8 , wherein the electronic component packaging container is a carrier tape.

10. The electronic component packaging container according to claim 9 , wherein the electronic component packaging container is a tray.

11. An electronic component packaging using the electronic component packaging container according to claim 8 .

Assignees

• Denka Company Ltd

Inventors

• YANAKA Ryosuke
• Fujiwara Junpei

Classifications

• B32B27/30 Primary

  comprising vinyl {(co)polymers; comprising acrylic (co)polymers} · CPC title

• B32B27/18 Primary

  characterised by the use of special additives · CPC title

• Y02W30/80

  Packaging reuse or recycling, e.g. of multilayer packaging (bio-packaging Y02W90/10) · CPC title

• B32B2250/24

  All layers being polymeric · CPC title

• B32B27/308

  comprising acrylic (co)polymers · CPC title