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Forming solid, adhesive-free composite of membrane filters and cellulosic cardboard

Assignee: Boehringer Ingelheim GmbH
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Filing: 1976-05-25
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Granted: 1977-08-16
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Expires: 1996-05-25
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Abstract

Abstract A solid, adhesive-free, layered composite material consisting of two clearly defined layers, one made of membrane filters and the other of porous material, the said composite material being formed by bringing a polymeric membrane filter forming substance in its gel condition into contact with the porous material, and solidifying the said gel on the porous material; the composite material is useful as a nutrient medium carrier for microbiological tests.

Inventors

  • 👤 Karl Buchta
  • 👤 Mohamed Abdou
  • 👤 Harald Woltersdorf

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 20:06
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/10; C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/18; Y; Y10; Y10S; Y10S435/00; Y10S435/805; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249962; Y10T428/249964; Y10T428/249965; Y10T428/31504; Y10T428/31725; Y10T428/31768; Y10T428/31772; Y10T428/31775; Y10T428/31855; Y10T428/3188; Y10T428/31895; Y10T428/31906; Y10T428/31971; Y10T428/31975

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 62 words
The method of forming a solid, adhesive-free, layered composite material composed of two clearly defined layers consisting of a membrane filter layer and a porous backing layer, comprising the steps of depositing on cellulosic cardboard a layer of a gelatinized polymeric membrane-forming substance between onset of synerisis and final solidification thereof, and allowing said membrane-forming substance to solidify on said cellulosic cardboard.
Claim 2
Independent Claim 62 words
The method of forming a solid, adhesive-free, layered composite material composed of two clearly defined layers consisting of a membrane filter layer and a porous backing layer, comprising the steps of depositing on cellulosic cardboard a layer of a gelatinized polymeric membrane-forming substance between onset of synerisis and final solidification thereof, and allowing said membrane-forming substance to solidify on said cellulosic cardboard.
Claim 3
Dependent Claim 23 words
The method of claim 1, where said polymeric membrane-forming substance is cellulose nitrite, cellulose acetate, gelatin, polyvinylchloride, polyvinylacetate, a polyamide or an alginate.
Claim 4
Dependent Claim 17 words
The method of claim 1, where said cellulosic cardboard is impregnated with a nutrient solution for microorganisms.
Claim 5
Dependent Claim 12 words
The method of claim 3, where said impregnated cellulosic cardboard is dried.
Claim 6
Dependent Claim 277 words
The method of claim 3, where said nutrient solution is an aqueous solution which contains about 0.25 to 1 gm of L-arginine, 0.5 to 2 gm of L-asparginic acid, 0.25 to 1 gm of L-crysteine, 1 to 4 gm of L-glutaminic acid, 0.1 to 0.4 gm glycocoll, 0.15 to 0.6 gm of L-histidine, 0.4 to 1.6 gm of L-leucine, 0.25 to 1 gm of L-isoleucine, 0.3 to 1.2 gm of L-lysine, 0.15 to 0.6 gm of L-methionine, 0.15 to 0.6 gm of L-phenylalanine, 0.2 to 0.8 gm of L-proline, 0.2 to 0.8 gm of L-threonine, 0.05 to 0.2 gm of tryptophane, 0.2 to 0.8 gm of L-tyrosine, 0.5 to 2 gm of L-valine, 1.5 to 6 gm of sodium chloride, 0.15 to 0.6 gm of potassium chloride, 0.5 to 2 gm of anhydrous sodium acetate, 0.5 to 2 gm of sodium pyruvate, 3 to 12 gm of sodium glycerophosphate pentahydrate, 0.025 to 0.1 gm of magnesium sulfate heptahydrate, 0.005 to 0.02 gm of adenine, 0.005 to 0.02 gm of guanine, 0.005 to 0.02 gm of uracil, 1 to 4 gm of D-glucose, 0.005 to 0.02 gm of inosite, 0.005 to 0.02 gm of choline chloride, 0.005 to 0.02 gm of nicotinic acid, 0.005 to 0.02 gm of thiamine hydrochloride, 0.0005 to 0.0002 gm of riboflavin, 0.003 to 0.012 gm of pyridoxin hydrochloride, 0.005 to 0.02 gm of calcium pantothenate, 0.005 to 0.02 gm of folic acid, 0.0001 0.0004 gm of biotin, 0.0025 to 0.01 gm of p-nitrophenylpropanetriol, 0.05 to 0.4 gm of pimaricin per liter of water, as well as the required quantity of sodium hydroxide in dilute aqueous solution for adjustment of the pH to 7.2.

References Cited (Backward Citations)

US1987930A Cited
US3052237A Cited
US3535194A Cited
US3914524A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-08-15 1981-02-14 1981-08-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-08-15 1985-02-14 1985-08-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-08-15 1989-02-14 1989-08-16 $7700.00 Window Closed / Lapsed

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