US4071636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing sheet-formed bactericidal article
Assignee: Panasonic Holdings Corp
•
Filing: 1975-07-11
•
Granted: 1978-01-31
•
Expires: 1995-07-11
Abstract
Abstract A sheet of partially acetalled polyvinyl alcohol is used as the substratum of the article, and a sparingly soluble silver halide is precipitated on the sheet from an aqueous phase such as an ammoniacal silver chloride solution.
Inventors
- 👤 Atsushi Nishino
- 👤 Kazunori Sonetake
- 👤 Hiroshi Kumano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:25
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/08; B01D39/083; A; A61; A61L; A61L2/00; A61L2/16; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; C; C02; C02F; C02F1/00; C02F1/50; C02F1/505; B01D2239/00; B01D2239/04; B01D2239/0407; B01D2239/0414; B01D2239/0421; B01D2239/0442; B01D2239/0464; B01D2239/0471; B01D2239/0478; B01D2325/00; B01D2325/48
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
158 words
A method of producing a sheet-formed bactericidal article for the sterilization of dechlorinated potable water in a water purifier, the article consisting of a cloth substrate and fine particles of silver chloride firmly deposited on the surfaces of the fiber filaments of the cloth substrate, the method comprising the steps of; soaking a non-woven cloth sheet of partially acetal-formed polyvinyl alcohol in an aqueous solution of silver nitrate in the concentration range from 1 to 20% by weight, the hydroxyl radicals in said partially acetal-formed polyvinyl alcohol having been subjected to partial condensation with an aldehyde to form acetal radicals ##STR3## such that the extent of the acetal formation is less than 50 mol% of polyvinyl alcohol; drying the soaked sheet to remove water; and soaking the dried sheet in an aqueous solution of sodium chloride in the concentration range from 1 to 20% by weight to convert said silver nitrate adhering to said sheet into silver chloride.
Claim 2
Independent Claim
158 words
A method of producing a sheet-formed bactericidal article for the sterilization of dechlorinated potable water in a water purifier, the article consisting of a cloth substrate and fine particles of silver chloride firmly deposited on the surfaces of the fiber filaments of the cloth substrate, the method comprising the steps of; soaking a non-woven cloth sheet of partially acetal-formed polyvinyl alcohol in an aqueous solution of silver nitrate in the concentration range from 1 to 20% by weight, the hydroxyl radicals in said partially acetal-formed polyvinyl alcohol having been subjected to partial condensation with an aldehyde to form acetal radicals ##STR3## such that the extent of the acetal formation is less than 50 mol% of polyvinyl alcohol; drying the soaked sheet to remove water; and soaking the dried sheet in an aqueous solution of sodium chloride in the concentration range from 1 to 20% by weight to convert said silver nitrate adhering to said sheet into silver chloride.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1, wherein said non-woven cloth sheet has a thickness between 0.01 and 5mm, the extent of the acetal formation being in the range between 5 and 30%.
Claim 4
Independent Claim
144 words
A method of producing a sheet-formed bactericidal article for the sterilization of dechlorinated potable water in a water purifier, the article consisting of a cloth substrate and fine particles of silver chloride firmly deposited on the surfaces of the fiber filaments of the cloth substrate, the method comprising the steps of; preparing a silver amine complex solution by dissolving 0.1 to 20% by weight of silver chloride in an aqueous ammonia solution ranging in concentration from 1 to 14% by weight; soaking a non-woven cloth sheet of partially acetal formed polyvinyl alcohol in said solution, the hydroxyl radicals in said partially acetal-formed polyvinyl alcohol having been subjected to partial condensation with an aldehyde to form acetal radicals ##STR4## such that the extent of the acetal formation is less than 50 mol% of polyvinyl alcohol; and drying the soaked sheet to evaporate water and ammonia.
Claim 5
Independent Claim
144 words
A method of producing a sheet-formed bactericidal article for the sterilization of dechlorinated potable water in a water purifier, the article consisting of a cloth substrate and fine particles of silver chloride firmly deposited on the surfaces of the fiber filaments of the cloth substrate, the method comprising the steps of; preparing a silver amine complex solution by dissolving 0.1 to 20% by weight of silver chloride in an aqueous ammonia solution ranging in concentration from 1 to 14% by weight; soaking a non-woven cloth sheet of partially acetal formed polyvinyl alcohol in said solution, the hydroxyl radicals in said partially acetal-formed polyvinyl alcohol having been subjected to partial condensation with an aldehyde to form acetal radicals ##STR4## such that the extent of the acetal formation is less than 50 mol% of polyvinyl alcohol; and drying the soaked sheet to evaporate water and ammonia.
Claim 6
Dependent Claim
33 words
A method as claimed in claim 3, wherein the soaking step is carried out at atmospheric pressure keeping the temperature of said solution in a range between -33 ° C and room temperature.
Claim 7
Dependent Claim
24 words
A method as claimed in claim 3, wherein the soaking step is carried out at a pressure of 20 kg/cm 2 at the highest.
Claim 8
Dependent Claim
34 words
A method as claimed in claim 3 wherein said non-woven cloth sheet has a thickness between 0.01 and 5mm, the extent of the acetal formation being in the range between 5 and 30 mol%.
References Cited (Backward Citations)
US1744281A
Cited
US2785106A
Cited
US2791518A
Cited
US3058845A
Cited
US3091554A
Cited
US3276996A
Cited
US3327859A
Cited
US3342729A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |