US4869909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing a medical vinyl chloride resin material
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1987-12-28
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Granted: 1989-09-26
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Expires: 2007-12-28
Abstract
Abstract A process for producing a medical resin material comprising the steps of (a) adding and dispersing a porous powder containing a pharmaceutical solution in the fine pores thereof to a solution of a polyvinyl chloride resin which is prepared by uniformly dissolving a polyvinyl chloride resin into an organic solvent, thereby preparing a uniform mixed solution; (b) shaping by utilizing the flow property of the mixed solution; and (c) solidifying the shaped mixed solution by evaporizing to remove the organic solvent.
Inventors
- 👤 Hideo Takahashi
- 👤 Kouichi Iwata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:16
CPC Classifications
A; A61; A61L; A61L33/00; A61L33/0005; A61L33/0047; A61K; A61K9/00; A61K9/14; A61K9/141; A61K9/143; A61L29/00; A61L29/12; A61L29/126; A61L33/0011
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
102 words
A process for producing a medical resin material comprising the steps of (a) adding and dispersing a porous powder containing a pharmaceutical solution in the fine pores thereof to a solution of a polyvinyl chloride resin which is prepared by uniformly dissolving a polyvinyl chloride resin having a polymerization degree of from 1,000 to 2,800 into an organic solvent, said pharmaceutical solution being insoluble or sparingly soluble in said organic solvent, thereby preparing a uniform mixed solution; (b) shaping by utilizing the flow property of said mixed solution; and (c) solidifying said shaped mixed solution by evaporation to remove said organic solvent.
Claim 2
Dependent Claim
102 words
A process for producing a medical resin material comprising the steps of (a) adding and dispersing a porous powder containing a pharmaceutical solution in the fine pores thereof to a solution of a polyvinyl chloride resin which is prepared by uniformly dissolving a polyvinyl chloride resin having a polymerization degree of from 1,000 to 2,800 into an organic solvent, said pharmaceutical solution being insoluble or sparingly soluble in said organic solvent, thereby preparing a uniform mixed solution; (b) shaping by utilizing the flow property of said mixed solution; and (c) solidifying said shaped mixed solution by evaporation to remove said organic solvent.
Claim 3
Dependent Claim
53 words
A process for producing a medical resin material as claimed in claim 1, wherein a coating layer is formed on a substrate by utilizing the flow property of said mixed solution, then said coating layer is solidified by evaporation to remove the organic solvent and said coating layer is fixed on said substrate.
Claim 4
Dependent Claim
54 words
A process for producing a medical resin material as claimed in claim 1, wherein said mixed solution is cast on a releasable substrate by utilizing the flow property of said mixed solution, said cast product is solidified by evaporation to remove said organic solvent, and then said solidified product is released from said substrate.
Claim 5
Dependent Claim
74 words
A process for producing a medical resin material as claimed in claim 1, wherein said organic solvent is evaporized to remove under stirring until said mixed solution is gelified to such a state that said mixed solution no longer has the flow property, then said gel-like composition is shaped by extrusion molding at a temperature lower than the boiling point of said organic solvent, and then said organic solvent is completely evaporated and removed.
Claim 6
Dependent Claim
71 words
A process for producing a medical resin material as claimed in claim 1, wherein two or more of mixed solutions having different pharmaceutical concentrations are shaped and solidified successively thereby forming two or more coating layers, provided that the pharmaceutical concentration of the inner layer of said solidified layers is higher than the pharmaceutical concentration of the layer on the side where the pharmaceutical substance of said pharmaceutical solution is eluted.
Claim 7
Dependent Claim
46 words
A process for producing a medical resin material as claimed in claim 1, wherein said organic solvent for dissolving said polyvinyl chloride resin is tetrahydrofuran, and said porous powder is silica gel powder impregnated in the pores thereof with a glycerine solution of heparin sodium salt.
Claim 8
Dependent Claim
45 words
A process for producing a medical re in material as claimed in claim 1, wherein said organic solvent for dissolving said polyvinyl chloride resin is tetrahydrofuran, and said porous powder is silica gel powder impregnated in the pores thereof with a glycerine solution of urokinase.
Claim 9
Dependent Claim
40 words
A process for producing a medical resin material as claimed in claim 1, wherein said organic solvent is employed in an amount of from 600 to 1,000 parts by weight per 100 parts by weight of said polyvinyl chloride resin.
Claim 10
Dependent Claim
48 words
A process for producing a medical resin material as claimed in claim 4, wherein said mixed solution no longer having the flow property contains said organic solvent in an amount of from 100 to 400 parts by weight per 100 parts by weight of said polyvinyl chloride resin.
References Cited (Backward Citations)
US4555398A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-25 | 1993-03-27 | 1993-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-25 | 1997-03-27 | 1997-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-25 | 2001-03-27 | 2001-09-26 | $7700.00 | Window Closed / Lapsed |