Patent US4481241A successfully refreshed from Google Patents.
US4481241A
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Core material for fiber reinforced plastic and process for its production
Assignee: Asahi Fiber Glass Co Ltd
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Filing: 1982-09-13
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Granted: 1984-11-06
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Expires: 2002-09-13
Abstract
Abstract A core material for a fiber reinforced plastic comprises a glass fiber mat composed of glass fiber bundles and having a bulk density of from 50 to 150 kg/m3 and a porous material filled in void spaces in the glass fiber mat. The porous material is composed of a mixture of a thermoplastic resin and a filler such as a hollow inorganic filler. The core material is prepared by impregnating a glass fiber mat composed of elongated glass fiber bundles, with a mixture of the filler and a dispersion of the thermoplastic resin in a dispersing medium and their evaporating the dispersing medium from the impregnated glass fiber mat.
Inventors
- 👤 Sadao Kawashima
- 👤 Heiichi Takei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:09
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/26; B29; B29C; B29C70/00; B29C70/02; B29C70/021; B29C70/025; B29C70/58; B29C70/66; B32B27/00; B32B27/12; B29C67/00; B29C67/02; B29C67/06; B29K; B29K2067/00; B29K2067/06; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/0854; B29K2105/10; B29K2105/16; B29K2105/165; B29K2309/00; B29K2309/08; B29K2709/00; B29K2709/08; B32B2262/00; B32B2262/10; B32B2262/101; B32B2305/00; B32B2305/02; B32B2305/026; B32B2307/00; B32B2307/70; B32B2307/718; B32B2307/72; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24298; Y10T428/24322; Y10T428/24331; Y10T428/25; Y10T428/252; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2993; Y10T428/2996; Y10T428/31504; Y10T428/31536
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
72 words
A core material for a fiber reinforced plastic comprising a perforated glass fiber mat composed of glass fiber bundles and having a bulk density of from 50 to 150 kg/m 3 and a porous material filled in void spaced in the glass fiber mat, said porous material being composed of a mixture of a thermoplastic resin and a filler wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent.
Claim 2
Dependent Claim
72 words
A core material for a fiber reinforced plastic comprising a perforated glass fiber mat composed of glass fiber bundles and having a bulk density of from 50 to 150 kg/m 3 and a porous material filled in void spaced in the glass fiber mat, said porous material being composed of a mixture of a thermoplastic resin and a filler wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent.
Claim 3
Dependent Claim
14 words
The core material according to claim 1 wherein the filler is hollow inorganic particles.
Claim 4
Dependent Claim
24 words
The core material according to claim 1 wherein the bulk density of the glass fiber mat is from 75 to 120 kg/m 3 .
Claim 5
Dependent Claim
44 words
The core material according to claim 1 wherein each glass fiber bundle is composed of from 50 to 200 glass fibers each having a diameter of from 13 to 25 microns and has a weight of from 20 to 250 g per 1,000 m.
Claim 6
Dependent Claim
15 words
The core material according to claim 1 wherein the glass fiber bundles are continuous strands.
Claim 7
Dependent Claim
20 words
The core material according to claim 1 wherein the glass fiber bundles have a length of at least 1 m.
Claim 8
Dependent Claim
21 words
The core material according to claim 1 wherein the filler is hollow glass beads or silus balloons, or a mixture thereof.
Claim 9
Dependent Claim
34 words
The core material according to claim 1 wherein the weight ratio of the thermoplastic resin as a solid component to the filler in the mixture is within a range of from 100:150 to 100:800.
Claim 10
Dependent Claim
34 words
The core material according to claim 1 wherein the weight ratio of the glass fiber mat to the glass fiber mat plus the porous material is within a range of from 100:150 to 100:450.
Claim 11
Dependent Claim
43 words
The core material according to claim 1 wherein perforations are provided in the core material at a rate of from 0.5 to 5 perforations per cm 2 and each perforation has a cross sectional area of from 0.3 to 3 mm 2 .
Claim 12
Dependent Claim
17 words
The core material according to claim 1 or 12 wherein the perforations have a triangular cross section.
Claim 13
Dependent Claim
19 words
The core material according to claim 1 wherein the porous material has a porosity of from 30 to 60%.
Claim 14
Dependent Claim
87 words
A sandwich panel, comprising: (a) a core material comprising a glass fiber mat composed of glass fiber bundles and having a bulk density of from 50 to 150 kg/m 3 and a porous material filled in the void spaced in the glass fiber mat, said porous material being composed of a mixture of a thermoplastic resin and a filler wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent, and (b) a fiber reinforced plastic surface layer bonded to a surface of said mat.
Claim 15
Dependent Claim
87 words
A sandwich panel, comprising: (a) a core material comprising a glass fiber mat composed of glass fiber bundles and having a bulk density of from 50 to 150 kg/m 3 and a porous material filled in the void spaced in the glass fiber mat, said porous material being composed of a mixture of a thermoplastic resin and a filler wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent, and (b) a fiber reinforced plastic surface layer bonded to a surface of said mat.
Claim 16
Dependent Claim
18 words
The sandwich panel of claim 13, wherein the glass fiber mat is provided with a number of perforations.
Claim 17
Dependent Claim
92 words
A process for producing a core material for FRP which comprises: impregnating a glass fiber mat composed of long glass fiber bundles with a mixture of a filler and a dispersion of a thermoplastic resin in a dispersing medium wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent, evaporating the dispersing medium from the impregnated glass fiber mat, and needle piercing to provide a number of perforations in the core material, wherein the resulting core material has a bulk density of from 50 to 150 kg/m 3 .
Claim 18
Dependent Claim
92 words
A process for producing a core material for FRP which comprises: impregnating a glass fiber mat composed of long glass fiber bundles with a mixture of a filler and a dispersion of a thermoplastic resin in a dispersing medium wherein the thermoplastic resin is an unsaturated polyester resin containing no cross-linking agent, evaporating the dispersing medium from the impregnated glass fiber mat, and needle piercing to provide a number of perforations in the core material, wherein the resulting core material has a bulk density of from 50 to 150 kg/m 3 .
Claim 19
Dependent Claim
13 words
The process according to claim 15 wherein the filler is hollow inorganic particles.
Claim 20
Dependent Claim
23 words
The process according to claim 15 wherein the bulk density of the glass fiber mat is from 75 to 120 kg/m 3 .
Claim 21
Dependent Claim
43 words
The process according to claim 15 wherein each glass fiber bundle is composed of from 50 to 200 glass fibers each having a diameter of from 13 to 25 microns and has a weight of from 20 to 250 g per 1,000 m.
Claim 22
Dependent Claim
15 words
The process according to claim 15 wherein the glass fiber bundle ss are continuous strands.
Claim 23
Dependent Claim
19 words
The process according to claim 15 wherein the glass fiber bundles have a length of at least 1 mm.
Claim 24
Dependent Claim
20 words
The process according to claim 15 wherein the filler is hollow glass beads or silus balloons, or a mixture thereof.
Claim 25
Dependent Claim
33 words
The process according to claim 15 wherein the weight ratio of the thermoplastic resin as a solid component to the filler in the mixture is within a range of from 100:150 to 100:800.
Claim 26
Dependent Claim
33 words
The process according to claim 15 wherein the weight ratio of the glass fiber mat to the glass fiber mat plus the porous material is within a range of from 100:150 to 100:450.
Claim 27
Dependent Claim
42 words
The process according to claim 15 wherein perforations are provided in the core material at a rate of from 0.5 to 5 perforations per cm 2 and each perforation has a cross sectional area of from 0.3 to 3 mm 2 .
Claim 28
Dependent Claim
16 words
The process according to claim 15 or 24 wherein the perforations have a triangular cross section.
Claim 29
Dependent Claim
18 words
The process according to claim 15 wherein the porous material has a porosity of from 30 to 60%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-06 | 1988-05-07 | 1988-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-06 | 1992-05-07 | 1992-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-06 | 1996-05-07 | 1996-11-06 | $7700.00 | Window Closed / Lapsed |