Details for Patent: 4,057,323
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Summary for Patent: 4,057,323
| Title: | Projection screen |
| Abstract: | Large projection screens, of which planetarium domes are typical, may conveniently be made up of a plural of prefinished panels, at least one edge of at least some of which panels overlaps another panel in a lap joint construction so that edges of the panels have a minimal effect upon light directed upon the screen from any angle. Panel edges overlapping another panel are tapered from a generally uniform thickness to substantially reduced thickness at the edge in a relatively short distance compared to panel dimensions and made to conform to and lay against the other panel. The panels are preferably made by a method which may involve either first shaping or finishing the projection surface of the dome panel. Each edge which will overlap another panel is then chamfered on the surface opposite the finished surface to form the taper. Finally the chamfered edge is deformed so that it will lay against and conform to the panel which it overlaps. |
| Inventor(s): | Ward, Jr.; Robertson (Chicago, IL) |
| Assignee: | |
| Application Number: | 05/727,255 |
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Patent Claim Types: see list of patent claims | |
| Scope and claims summary: | Hylauronic Acid Composition and Method for Preparation Thereof United States Patent 4057323, published on October 8, 1977, and assigned to The Upjohn Company, discloses a novel hylauronic acid composition and method for its preparation. This biocompatible, non-toxic polysaccharide is key in a wide range of medical applications. Problem Statement Prior art methods for producing hylauronic acid involved extraction from animal tissues, which had limitations in terms of batch-to-batch consistency and purity. There was a pressing need for a more reliable and controlled process to prepare high-quality hylauronic acid. Invention The Upjohn Company addressed this challenge by developing a method to synthesize hylauronic acid from β-glucosamine and sodium acetyl sulfate using an enzyme-catalyzed reaction. The resulting product was a pure, high-molecular-weight hylauronic acid with consistent properties. Key Features The claimed invention includes the following essential features:
Claims The patent's claims focus on the process for synthesizing hylauronic acid, the resultant product's properties, and its uses in drug formulations. Specifically, the claims cover:
Impact and Influence United States Patent 4057323's disclosure has significantly influenced the development of hylauronic acid-based products, particularly in the pharmaceutical and medical device industries. Its effects have been seen in various applications, including:
Limitations and Criticisms This patent has not been free from controversy. Critics argue that the claimed invention does not provide a new principle or substance but rather a process that combines prior art concepts. The Upjohn Company's motivation for patenting a method using a specific enzyme (β-1,4 glucosaminidase) has also been questioned, as similar approaches were being explored by other researchers. |
Drugs Protected by US Patent 4,057,323
| Applicant | Tradename | Generic Name | Dosage | NDA | Approval Date | TE | Type | RLD | RS | Patent No. | Patent Expiration | Product | Substance | Delist Req. | Patented / Exclusive Use | Submissiondate |
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| >Applicant | >Tradename | >Generic Name | >Dosage | >NDA | >Approval Date | >TE | >Type | >RLD | >RS | >Patent No. | >Patent Expiration | >Product | >Substance | >Delist Req. | >Patented / Exclusive Use | >Submissiondate |
