US4447479A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastics sheet material and articles produced therefrom
Assignee: Plastona John Waddington Ltd
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Filing: 1980-10-28
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Granted: 1984-05-08
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Expires: 2000-10-28
Abstract
Abstract This invention relates to plastic sheet material, and in particular concerns the production of a plastics sheet material which has a wide range of uses, because of the properties thereof.
Inventors
- 👤 Peter Harrison
- 👤 Thomas N. Gaunt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:51
CPC Classifications
B; B65; B65D; B65D5/00; B29; B29C; B29C48/00; B29C48/022; B29C48/03; B29C48/07; B29C48/08; B29C48/25; B29C48/285; B29C48/297; B29K; B29K2105/00; B29K2105/06; B29K2105/12; B65D2301/00; B65D2301/20; Y; Y10; Y10S; Y10S273/00; Y10S273/12; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/1331; Y10T428/1352; Y10T428/1372; Y10T428/25; Y10T428/256; Y10T428/258; Y10T428/259; Y10T428/26; Y10T428/268; Y10T428/31504; Y10T428/31855; Y10T428/31938
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
119 words
A cardboard-like material free of styrene resins and elastomers that retains its dead-fold characteristics manufactured by compounding 5-70 parts by weight of inorganic particulate material with 95 to 30 parts by weight of polyolefin resin selected from polypropylene-ethylene sequential copolymer; polypropylene-ethylene random copolymer; or any mixture of these, the compounding being carried out essentially by mechanical working to generate heat, and to disperse the inorganic material evenly throughout the resin so as to produce a molten mass of uniform consistency having a melt flow index of between 0.55 and 2.2 cc/10 minutes at 230° C. under a load of 2.16 Kg and subsequently converting the mass into the sheet in a thickness of 0.1-1.2 mm by extrusion or calendering.
Claim 2
Dependent Claim
119 words
A cardboard-like material free of styrene resins and elastomers that retains its dead-fold characteristics manufactured by compounding 5-70 parts by weight of inorganic particulate material with 95 to 30 parts by weight of polyolefin resin selected from polypropylene-ethylene sequential copolymer; polypropylene-ethylene random copolymer; or any mixture of these, the compounding being carried out essentially by mechanical working to generate heat, and to disperse the inorganic material evenly throughout the resin so as to produce a molten mass of uniform consistency having a melt flow index of between 0.55 and 2.2 cc/10 minutes at 230° C. under a load of 2.16 Kg and subsequently converting the mass into the sheet in a thickness of 0.1-1.2 mm by extrusion or calendering.
Claim 3
Dependent Claim
24 words
Sheet material according to claim 1 wherein the resin is a sequential copolymer of polypropylene with from 10 to 35% by weight of ethylene.
Claim 4
Dependent Claim
23 words
Sheet material according to claim 1, wherein the solid particulate inorganic material has a hardness of less than 5.5 on the Moh's scale.
Claim 5
Dependent Claim
25 words
Sheet material according to claim 3, wherein the solid particulate inorganic material is capable of passing through sieve 140 as defined in ASTM Designation E11-61.
Claim 6
Dependent Claim
30 words
Sheet material according to claims 3 or 4, wherein at least 30% by weight of the particles of inorganic material have a largest dimensions of between 10 and 18 microns.
Claim 7
Dependent Claim
15 words
Sheet material according to claim 1, wherein the inorganic material is free from fibrous components.
Claim 8
Dependent Claim
29 words
Sheet material according to claim 1, wherein the sheet material includes a soap to reduce the co-efficient of friction of the particles of inorganic material one relative to another.
Claim 9
Dependent Claim
12 words
Sheet material according to claim 7, wherein the soap includes calcium stearate.
Claim 10
Dependent Claim
25 words
Sheet material according to claim 1, wherein the inorganic particulate material includes one or more of the following: talc; calcium carbonate; dolomite; kaolin; and gypsum.
Claim 11
Dependent Claim
30 words
Sheet material according to claim 1, wherein the sheet material includes from 1 to 3% by weight of a pigment having a hardness of less than 6.8 on Moh's scale.
Claim 12
Dependent Claim
12 words
Sheet material according to claim 10, wherein the pigment is titanium dioxide.
Claim 13
Dependent Claim
14 words
Sheet material according to claim 11, wherein the titanium dioxide is anatose titanium dioxide.
Claim 14
Dependent Claim
14 words
Sheet material according to claim 11, wherein the titanium dioxide is rutile titanium dioxide.
Claim 15
Dependent Claim
31 words
Sheet material according to claim 11, 12 or 13 wherein the titanium dioxide is coated with up to 5% by weight of alumina and up to 2% by weight of silica.
Claim 16
Dependent Claim
22 words
Sheet material according to claim 1 wherein the pigment is used in combination with up to 1/2% by weight of optical brightener.
Claim 17
Dependent Claim
19 words
Sheet material according to claim 1 wherein the surface of the sheet material is subjected to on oxidation treatment.
Claim 18
Dependent Claim
18 words
Sheet material according to claim 1, wherein surface of the sheet material is subjected to a corona discharge.
Claim 19
Dependent Claim
14 words
Sheet material according to claim 1, wherein the composition includes the anti-oxidant phenol thioester.
Claim 20
Dependent Claim
14 words
Sheet material according to claim 1, including a minor amount of a blowing agent.
Claim 21
Dependent Claim
24 words
Sheet material according to claim 19, wherein the blowing agent is introduced in solid form into the compounding operation in producing the molten mass.
Claim 22
Dependent Claim
26 words
Sheet material according to claim 19 or 20, wherein the blowing agent is introduced in an amount equal to 0.4% by weight of the molten mass.
Claim 23
Dependent Claim
14 words
Sheet material according to claim 21, wherein the blowing agent is P-toluene sulfonyl semicarbazide.
Claim 24
Dependent Claim
12 words
Sheet material according to claim 1, wherein the sheet material is extruded.
Claim 25
Dependent Claim
14 words
Sheet material according to claim 1, when cut and printed to define playing cards.
Claim 26
Dependent Claim
10 words
Sheet material according to claim 1, when thermoformed into articles.
Claim 27
Dependent Claim
18 words
Sheet material according to claim 1 when cut and creased to form packaging container or other article blanks.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-08 | 1987-11-07 | 1988-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-08 | 1991-11-07 | 1992-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-08 | 1995-11-07 | 1996-05-08 | $7700.00 | Window Closed / Lapsed |