.

Pharmaceutical Business Intelligence

  • Anticipate P&T budget requirements
  • Evaluate market entry opportunities
  • Find generic sources and suppliers
  • Predict branded drug patent expiration

► Plans and Pricing

Upgrade to enjoy subscriber-only features like email alerts and data export. See the Plans and Pricing

DrugPatentWatch Database Preview

Details for Patent: 4,683,288

« Back to Dashboard

Details for Patent: 4,683,288

Title: Polymer and its production
Abstract:A polymer or copolymer of lactic acid and/or glycolic acid which has a weight-average molecular weight of not less than about 5,000 and a dispersity of about 1.5 to 2 is advantageously used as a biodegradable polymer or copolymer for medical preparation.
Inventor(s): Tanaka; Motoaki (Saitama, JP), Ogawa; Yasuaki (Osaka, JP), Miyagawa; Tsutomu (Saitama, JP), Watanabe; Toshio (Saitama, JP)
Assignee: Waco Pure Chemical Ind. Inc. (Osaka, JP) Takeda Chemical Industries, Ltd. (Osaka, JP)
Filing Date:Jul 03, 1985
Application Number:06/751,671
Claims:1. In a method for producing a polymer or copolymer of lactic acid and/or glycolic acid by subjecting lactic acid and/or glycolic acid to a polycondensation reaction, an improvement which comprises employing a solid inorganic acid catalyst as a polycondensation catalyst, wherein the solid inorganic acid catalyst is one selected from the group consisting of acid clay, activated clay, bentonite, kaolin, talc, aluminum silicate, magnesium silicate, alumina bolia and silicic acid.

2. A method as claimed in claim 1, wherein the weight-average molecular weight of the polymer or copolymer is about not less than 5,000 and a dispersity of it is about 1.5 to 2.

3. A method as claimed in claim 1, wherein the weight-average molecular weight of the polymer or copolymer is about 5,000 to 30,000 and a dispersity of it is about 1.5 to 2.

4. A method in claim 1, wherein the polymer consists of lactic acid unit.

5. A method as claimed in claim 1, wherein the copolymer consists of lactic acid and glycolic acid units.

6. A method as claimed in claim 5, wherein the copolymer ratio is about 50 to 95 weight % of lactic acid and about 50 to 5 weight % of glycolic acid.

7. A method as claimed in claim 5, wherein the copolymer ratio is about 60 to 95 weight % of lactic acid and about 40 to 5 weight % of glycolic acid.

8. A method as claimed in claim 5, wherein the copolymer ratio is about 60 to 85 weight % of lactic acid and about 40 to 15 weight % of glycolic acid.

9. A method as claimed in claim 5, wherein the copolymer ratio is about 75.+-.2 mol % of lactic acid and about 25.+-.2 mol % of glycolic acid.

10. A method as claimed in claim 1, wherein the solid inorganic acid catalyst is one selected from the group consisting of acid clay, activated clay, kaolin, bentonite and aluminium silicate.

11. A method as claimed in claim 1, wherein the solid inorganic acid catalyst is acid clay.

12. A method as claimed in claim 1, wherein the solid inorganic acid catalyst is activated clay.

13. A method as claimed in claim 1, wherein the solid inorganic acid catalyst is aluminium silicate.
« Back to Dashboard

For more information try a trial or see the database preview and plans and pricing

Drugs may be covered by multiple patents or regulatory protections. All trademarks and applicant names are the property of their respective owners or licensors. Although great care is taken in the proper and correct provision of this service, thinkBiotech LLC does not accept any responsibility for possible consequences of errors or omissions in the provided data. The data presented herein is for information purposes only. There is no warranty that the data contained herein is error free. thinkBiotech performs no independent verifification of facts as provided by public sources nor are attempts made to provide legal or investing advice. Any reliance on data provided herein is done solely at the discretion of the user. Users of this service are advised to seek professional advice and independent confirmation before considering acting on any of the provided information. thinkBiotech LLC reserves the right to amend, extend or withdraw any part or all of the offered service without notice.

`abc