EP0083723A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electromagnetic wave-shielding materials
Assignee: Resonac Holdings Corp
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Filing: 1982-11-24
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Granted: —
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Expires: 2002-11-24
Abstract
Abstract An electromagnetic wave-shielding material is disclosed. The material is comprised of one or more electromagnetic wave-shielding layers and one or more surface layers. The shielding layers are comprised of a thermoplastic resin, an aluminum or aluminum alloy and electrically conductive carbon black. The surface layers are comprised substantially of thermoplastic resin. The proportion of the carbon black and aluminum in the shielding layer are from 5 to 50% by volume and 5 to 50% by volume, respectively, provided the total proportion of the carbon black and aluminum is 10 to 60% by volume. The different in solubility parameter between the thermoplastic resin of the surface layer and the thermoplastic resin of the shielding layer is 3.0 or less. The material has superior mechanical strength and electromagnetic wave-shielding properties.
Inventors
- 👤 Masahiro Kanda
- 👤 Tesuya Hatakeyama
- 👤 Yusuke Morito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 20:52
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0073; H05K9/0081; H05K9/0083
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
111 words
An electromagnetic wave-shielding material comprising: an electromagnetic wave-shielding layer comprised of: (A) a thermoplastic resin; (B) an aluminum or aluminum alloy; and (C) electrically conductive carbon black; and a surface layer comprised of a thermoplastic resin, wherein, the proportions of the electrically conductive carbon black and the metal in the electromagnetic wave-shielding layer are from 5 to 50% by volume, respectively, provided that the total proportion of the carbon black and the aluminum or aluminum alloy is from 10 to 60% by volume, and the difference in solubility parameter between the thermoplastic resin of the surface layer and the thermoplastic resin (A) of the electromagnetic wave-shielding layer is 3.0 or less.
Claim 2
Dependent Claim
111 words
An electromagnetic wave-shielding material comprising: an electromagnetic wave-shielding layer comprised of: (A) a thermoplastic resin; (B) an aluminum or aluminum alloy; and (C) electrically conductive carbon black; and a surface layer comprised of a thermoplastic resin, wherein, the proportions of the electrically conductive carbon black and the metal in the electromagnetic wave-shielding layer are from 5 to 50% by volume, respectively, provided that the total proportion of the carbon black and the aluminum or aluminum alloy is from 10 to 60% by volume, and the difference in solubility parameter between the thermoplastic resin of the surface layer and the thermoplastic resin (A) of the electromagnetic wave-shielding layer is 3.0 or less.
Claim 3
Dependent Claim
61 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the thermoplastic resin (A) is selected from the group consisting of: (i) modified polyolefins; (ii) copolymers of ethylene and unsaturated car- boxilic acids and/or anhydrides thereof; (iii) copolymers of ethylene and alkyl acrylate and/or alkyl methacrylate; (iv) styrene-based resins; (v) vinyl chloride-based resins; . (vi) polyamide resins; and (vii) polycarbonate resins.
Claim 4
Dependent Claim
30 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the aluminum or aluminum alloy is in the form of particles having a mean size of 250 to 20 mesh.
Claim 5
Dependent Claim
43 words
An electromagnetic wave-shielding material is claimed in Claim 1, wherein the aluminum or aluminum alloy is in the form of fiberous aluminum or fiberous aluminum alloy having a diameter of from 0.002 to 0.50 mm and a length of 10 mm or less.
Claim 6
Dependent Claim
23 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the aluminum alloy has an aluminum content of 80% by weight or more.
Claim 7
Dependent Claim
20 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the aluminum or aluminum alloy is in the form flake.
Claim 8
Dependent Claim
27 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the carbon black has a specific surface area of from 200 to 1200 m 2 / g.
Claim 9
Dependent Claim
37 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the difference in the solubility parameter between the thermoplastic resin in the surface layer and the thermoplastic resin in the electromagnetic wave-shielding layer is 2.7 or less.
Claim 10
Dependent Claim
37 words
An electromagnetic wave-shielding material as claimed in Claim 8, wherein the difference in the solubility parameter between the thermoplastic resin in the surface layer and the thermoplastic resin in the electromagnetic wave-shielding layer is 2.5 or less.
Claim 11
Dependent Claim
24 words
An electromagnetic wave-shielding material as claimed in Claim 1, wherein the material is comprised of the electromagnetic wave-shielding layer sandwiched with the surface layers.
References Cited (Backward Citations)
No citation records indexed.
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