US4435305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chemical formulation for reclaiming silk screens
Assignee: Individual
•
Filing: 1983-01-24
•
Granted: 1984-03-06
•
Expires: 2003-01-24
Abstract
Abstract A non-aqueous liquid chemical formulation for reclaiming silk screens by removing simultaneously the stencil emulsion and ink is described. The silk screen is contacted with the liquid for a period sufficient to loosen the hardened stencil emulsion and the ink from the surface of the silk screen. The non-aqueous liquid chemical formulation is typically placed in a carbon steel tank at ambient temperature and the silk screen is immersed in the liquid for approximately five minutes. Alternately, the silk screen can be sprayed with the liquid formulation and allowed to soak for approximately seven minutes. The softened ink and stencil emulsion are then removed by using a high pressure water jet stream. The formulation contains an alkali metal hydroxide, a monohydric or polyhydric alcohol, a glycol ether, a surfactant, aliphatic and/or aromatic hydrocarbons and a wax.
Inventors
- 👤 Skevos N. Tsoukalas
- 👤 John H. Andros
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:57
CPC Classifications
C; C11; C11D; C11D7/00; C11D7/02; C11D7/04; C11D7/06; C11D3/00; C11D3/43
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
100 words
A method for removing hardened stencil emulsion and ink from the surface of a silk screen comprising the steps of: contacting said silk screen at ambient temperatures for a period of time sufficient to loosen said stencil and ink from said silk screen surface with a solution of a non-aqueous formulation consisting essentially of approximately 20-60% by weight of a C 1 -C 12 alcohol, 2-10% by weight of an alkali metal hydroxide and 20-60% by weight of a hydrocarbon solvent and separating said loosened stencil and ink from said silk screen surface by a high pressure water jet stream.
Claim 2
Independent Claim
100 words
A method for removing hardened stencil emulsion and ink from the surface of a silk screen comprising the steps of: contacting said silk screen at ambient temperatures for a period of time sufficient to loosen said stencil and ink from said silk screen surface with a solution of a non-aqueous formulation consisting essentially of approximately 20-60% by weight of a C 1 -C 12 alcohol, 2-10% by weight of an alkali metal hydroxide and 20-60% by weight of a hydrocarbon solvent and separating said loosened stencil and ink from said silk screen surface by a high pressure water jet stream.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the said alkali metal hydroxide is potassium hydroxide.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein the said alcohol is isobutyl alcohol.
Claim 5
Dependent Claim
15 words
The method of claim 1 wherein the said hydrocarbonds are mineral spirits and gum turpentine.
Claim 6
Dependent Claim
46 words
The method of claim 1 wherein the formulation consists essentially of: ______________________________________
Component % By Weight
______________________________________
Isobutyl Alcohol 20-50
Ethylene Glycol 5-30
Potassium Hydroxide 2-10
Alkyl Phenoxy Polyethoxy Ethanol
2-10
Mineral Spirits 20-50
Gum Turpentine 20-50
Parafin Wax 0.5-2
Ethylene Glycol Monobutyl Ether
2-10
______________________________________
Claim 7
Dependent Claim
47 words
The method of claim 1 wherein the formulation consists essentially of: ______________________________________
Component % By Weight
______________________________________
Isobutyl Alcohol 27
Ethylene Glycol 17
Potassium Hydroxide 5
Alkyl Phenoxy Polyethoxy Ethanol
6
Mineral Spirits 20
Gum Turpentine 20
Parafin Wax 1
Ethylene Glycol Monobutyl Ether
4
100
______________________________________
Claim 8
Dependent Claim
15 words
The method of claim 1 carried out at ambient temperature without the application of heat.
Claim 9
Dependent Claim
18 words
The formulation of claim 1 wherein the composition is effectively removing the hardened stencil emulsion and ink simultaneously.
Claim 10
Dependent Claim
68 words
A non-aqueous formulation for removing hardened stencil emulsion and ink from the surface of a silk screen said formulation consisting essentially of: 2-10% of an alkali metal hydroxide, 20-50% of an alcohol containing 1-12 carbon atoms, 5-30% of a glycol containing 1-6 carbon atoms, 2-10% an anionic or nonionic surfactant, 2-10% of a glycol monoalkyl ether and 20-40% of a non-polar hydrocarbon solvent, said percentage being by weight.
Claim 11
Dependent Claim
68 words
A non-aqueous formulation for removing hardened stencil emulsion and ink from the surface of a silk screen said formulation consisting essentially of: 2-10% of an alkali metal hydroxide, 20-50% of an alcohol containing 1-12 carbon atoms, 5-30% of a glycol containing 1-6 carbon atoms, 2-10% an anionic or nonionic surfactant, 2-10% of a glycol monoalkyl ether and 20-40% of a non-polar hydrocarbon solvent, said percentage being by weight.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-06 | 1987-09-05 | 1988-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-06 | 1991-09-05 | 1992-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-06 | 1995-09-05 | 1996-03-06 | $7700.00 | Window Closed / Lapsed |