Patent US4940558A successfully refreshed from Google Patents.
US4940558A
Expired / Lapsed
US
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Method for molding artificial urethane rock
Assignee: Illinois Tool Works Inc
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Filing: 1989-07-10
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Granted: 1990-07-10
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Expires: 2009-07-10
Abstract
Abstract A method for producing a simulated rock by spraying a high density polyurethane elastomer in a flexible rubber mold. The rubber may be natural rubber or synthetic rubber. A rock is produced in molded form, not limited in size. A flexible mold is prepared by applying numerous coats of liquid uncured rubber forming materials, such as latex rubber, upon the rock exterior in combination with a fabric embedded within the rubber latex layers. A supporting cradle for the rubber mold is produced by spraying a low density urethane foam composition over the mold. The mold and cradle are stripped from the rock and are sprayed with a two component structural urethane system employing an isocyanate component and a polyol component with appropriate catalysts, fillers and additives. The structural urethane elastomer is built up to substantial thickness to provide a strong rigid load bearing polyurethane molded rock simulating the original rock surface with curing taking place in a matter of seconds or minutes. After cooling, the molded urethane rock is removed and the mold may be reused for repeated molding operations. Where desired, the molded urethane rock may be reinforced with an inner layer of low density urethane foam to reduce the amount of structural urethane employed.
Inventors
- 👤 Enos D. Jarboe
- 👤 Rodney D. Jarboe
- 👤 Edward M. Barclay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:48
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/38; B29C33/40; B29C33/405; B29C33/3842; B29C33/3857; B29C33/56; B29C41/00; B29C41/003; B29C2033/3864; B29C41/02; B29C41/08; B29K; B29K2075/00; B29K2821/00; B29K2875/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
158 words
A method for molding an artificial urethane rock which comprises selecting a rock to be reproduced, creating a flexible rubber mold and supporting cradle having a mold cavity conforming to the exterior of said rock, said mold having a substantial degree of flexibility and being created by applying an uncured liquid rubber forming material to said rock, curing said uncured liquid rubber forming material to produce said rubber mold, said cradle being formed by applying by spraying a low density urethane foam forming mixture to the exterior of the rubber mold to provide a self-supporting cradle, spraying a two sided urethane composition into the mold cavity, said urethane composition comprising an isocyanate side and a polyol side and being mixed in a spray gun in a spray-in-mold process, carrying out said spraying to build up the molded artificial urethane rock to a desired thickness and stripping said cradle and mold from the molded artificial urethane rock after curing.
Claim 2
Independent Claim
158 words
A method for molding an artificial urethane rock which comprises selecting a rock to be reproduced, creating a flexible rubber mold and supporting cradle having a mold cavity conforming to the exterior of said rock, said mold having a substantial degree of flexibility and being created by applying an uncured liquid rubber forming material to said rock, curing said uncured liquid rubber forming material to produce said rubber mold, said cradle being formed by applying by spraying a low density urethane foam forming mixture to the exterior of the rubber mold to provide a self-supporting cradle, spraying a two sided urethane composition into the mold cavity, said urethane composition comprising an isocyanate side and a polyol side and being mixed in a spray gun in a spray-in-mold process, carrying out said spraying to build up the molded artificial urethane rock to a desired thickness and stripping said cradle and mold from the molded artificial urethane rock after curing.
Claim 3
Dependent Claim
18 words
The method of claim 1 in which the uncured liquid rubber forming material is a silicone forming material.
Claim 4
Dependent Claim
18 words
The method of claim 1 in which the uncured liquid rubber forming material is a urethane forming material.
Claim 5
Dependent Claim
38 words
The method of claim 1 in which the mold and supporting cradle is created by applying the liquid uncured rubber forming material on said rock in a multiplicity of layers, and a fabric is embedded between said layers.
Claim 6
Dependent Claim
17 words
The method of claim 1 in which selected pigments and fillers are added in the polyol side.
Claim 7
Dependent Claim
45 words
The method of claim 1 in which the artificial rock and rubber mold are removed from the cradle, the mold is then removed from the artificial rock and the mold is repositioned removed from the artificial rock and the mold is repositioned in the cradle.
Claim 8
Dependent Claim
32 words
The method of claim 1 in which the low density urethane foam has a density of one to ten pounds per cubic foot and is applied by spraying to a substantial thickness.
Claim 9
Dependent Claim
27 words
The method of claim 1 in which the molded urethane rock is reinforced by spraying a low density urethane foam upon an inner surface of said rock.
Claim 10
Dependent Claim
39 words
The method of claim 1 in which the two sides of the urethane composition are solvent free and are introduced separately into a reaction chamber of a spray gun to provide a 100% solids polyurethane artificial rock mold composition.
Claim 11
Dependent Claim
30 words
The method of claim 9 in which the isocyanate and polyol sides are introduced to the spray gun in a volume ratio of isocyanate to polyol of 1:1 to 1:8.
Claim 12
Dependent Claim
23 words
The method of claim 9 in which the isocyanate side comprises a polymeric 4-4'-diphenylmethane diisocyanate having a functionality of free NCO of 28-34%.
Claim 13
Dependent Claim
16 words
The method of claim 9 in which the polyol is a hydroxy containing polyester or polyether.
Claim 14
Dependent Claim
17 words
The method of claim 12 in which the polyol comprises a polyether triol, polyetherdiol and a polyethertetrol.
Claim 15
Dependent Claim
47 words
The method of claim 12 in which the polyol comprises substantially 22% polyethertriol having a hydroxy number of 250, 49% of a polyetherdiol having a hydroxy number of 28, 13% of polyethertetrol having a hydroxy number of 770, a glycol extender and a catalyst of dibutyltin dilaurate.
Claim 16
Dependent Claim
33 words
The method of claim 9 in which the isocyanate side comprises a polymeric 4-4'-diphenylmethane diisocyanate having a functionality of free NCO of 28-34% and the polyol is a hydroxy containing polyester or polyether.
Claim 17
Dependent Claim
46 words
The method of claim 15 in which the polyol comprises substantially 22% polyethertriol having a hydroxy number of 250, 49% of a polyetherdiol having a hydroxy number of 28, 13% of polyethertetrol having a hydroxy number if 770, a glycol extender and a catalyst dibutyltin dilaurate.
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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) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |