The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 01, 1992
Filed:
Mar. 28, 1991
Masami Takuno, Kawasaki, JP;
Showa Denko Kabushiki Kaisha, Tokyo, JP;
Abstract
A hygroscopic laminate comprises a hygroscopic layer comprising a gas permeable film, and a water-absorbing polymer and at least one humectant selected from the group consisting of acetic acid, propionic acid, glycolic acid, lactic acid, hydracrylic acid, pyruvic acid and pyrrolidonecarboxylic acid and sodium, potassium, calcium and magnesium salts of these acids, which are wrapped in the gas permeable film; a porous non-water retention sheet; and a water impermeable sheet, the porous non-water retention sheet being disposed on one side of the hygroscopic layer and the water impermeable sheet being disposed on the other side of the hygroscopic layer, to thereby sandwich the hygroscopic layer. The hygroscopic laminate controls the relative humidity in a packaged system to 20 to 40%.