USH555H - Moisture absorbing anti-arcing coating and method for applying same - Google Patents
Moisture absorbing anti-arcing coating and method for applying same Download PDFInfo
- Publication number
- USH555H USH555H US06/596,786 US59678684A USH555H US H555 H USH555 H US H555H US 59678684 A US59678684 A US 59678684A US H555 H USH555 H US H555H
- Authority
- US
- United States
- Prior art keywords
- arcing
- coating
- isocyanate
- moisture
- recited
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
- C09D175/04—Polyurethanes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/08—Processes
- C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/302—Water
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
- C09J133/04—Homopolymers or copolymers of esters
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
- C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
- C08L2666/14—Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
- C08L75/04—Polyurethanes
Definitions
- This invention relates generally to ceramic insulators and more particularly to a composition for coating such insulators in order to improve their anti-arcing capability.
- Ceramic components intended for high voltage insulator service must be virtually moisture free in order to preclude failure due to arcing or flashover.
- a standard practice for removing moisture from ceramic insulators is to bake the insulators at elevated temperatures under vacuum conditions. While still under vacuum, an anti-arcing coating is applied to the insulator.
- Such anti-arcing compounds usually consist of an acrylic polymer dissolved in a solvent, several varieties of which are commercially available.
- one object of the present invention is to improve the anti-arcing capability of high voltage ceramic insulators which are temperature or pressure sensitive.
- Another object of this invention is to prevent high voltage failure of ceramic insulators due to residual moisture in the ceramic material.
- a further object of this invention is to chemically tie up residual water in high voltage ceramic components by incorporating a moisture active material in an anti-arcing coating applied to the surface of such components.
- a still further object of this invention is to reduce the brittleness of the anti-arcing coating applied to high voltage ceramic insulators.
- Yet anther object of this invention is to visually indicate the presence of high levels of moisture in high voltage ceramic insulators when the anti-arcing coating is applied.
- Still another object of this invention is to provide a method for improving the anti-arcing characteristic of high-voltage ceramic insulators which cannot be baked at elevated temperatures to remove trace amounts of moisture.
- Yet a further object of this invention is to provide a high-voltage ceramic insulator which is highly resistant to arcing without the usual bake drying at elevated temperatures.
- a moisture absorbing, anti-arcing compound applied to the surface of a high voltage ceramic insulator.
- This compound is formed by intermixing an isocyanate resin with a generic anti-arcing compound of the type comprising an acrylic polymer dissolved in a solvent.
- the isocyanate resin combines with the solvent to form a moisture active agent which chemically ties-up residual moisture in the ceramic, thereby preventing diffusion into the anti-arcing coating.
- composition according to this invention incorporates a hydrophilic organic material in a generic anti-arcing compound.
- a hydrophilic organic material generally consist of an acrylic polymer dissolved in a solvent.
- Typical solvents used are toluene and methyl-ethyl-ketone (MEK).
- isocyanate-terminated prepolymers or isocyanate resins will react with water to form other anhydrous compounds.
- the inventors have discovered that by intermixing such isocyanate resins with the anti-arcing coating before applying the coating to a ceramic insulator, residual moisture in the ceramic is tied up chemically and thus will not degrade the electrical properties of the anti-arcing compound.
- Toluene diisocyanate and 4,4'-diphenylmethane diisocyanate bis-methylene diisocyanate
- the isocyanate resin may be mixed in with the anti-arcing compound prior to application.
- the proportion of isocyanate resin to be added should be on the order of 1% or more. Although larger proportions will result in greater moisture absorbability, there is a point at which the dielectric strength of the composition will begin to degrade.
- the upper limit on the amount of isocyanate resin to be used is thus a function of the dielectric strength degradation which can be tolerated for a given application. Once an acceptable level of dielectric strength is selected for a given application, then the maximum amount of isocyanate resin can be readily determined. The exact relation between the two parameters can be easily determined by experiment. This will of course vary depending on the manufacturer and grade of the anti-arcing coating as well as the isocyanate resin.
- the process for applying the composition would comprise the standard steps of cleaning the surface with a surfactant and then drying under vacuum conditions.
- the moisture absorbing, anti-arcing coating may then be applied by either dipping, brushing-on, or spraying.
- the entire process may be done at room temperature or at any temperature above 30° F., but within the temperature limit of the particular ceramic material.
- the isocyanate resin will also act as an external plasticizer to reduce the normal brittleness of the anti-arcing compound.
- the impact resistance of the coating should thereby be improved.
- the isocyanate prepolymer will generate visible bubbles which would readily indicate the existence of such moisture. Such visual indication would prevent use of ceramics having retained moisture levels which are greater than the isocyanate prepolymer could handle.
- a moisture absorbing, anti-arcing composition which may be applied to the surface of a high voltage ceramic insulator.
- the moisture absorbing component reacts with residual moisture in the ceramic material and thus prevents it from diffusing into and degrading the anti-arcing component.
- An improved ceramic insulator is thereby provided.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Organic Insulating Materials (AREA)
- Polyurethanes Or Polyureas (AREA)
Abstract
A moisture absorbing, anti-arcing compound comprises a mixture of a moist active isocyanate resin and a generic anti-arcing compound. The isocyanate resin reacts with residual moisture in a high voltage ceramic insulator, thus tying it up chemically. This prevents diffusion of the moisture into the anti-arcing compound and resultant degradation. The compound according to this invention is especially useful for ceramics which may not be baked dry at elevated temperatures.
Description
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
This invention relates generally to ceramic insulators and more particularly to a composition for coating such insulators in order to improve their anti-arcing capability.
Ceramic components intended for high voltage insulator service must be virtually moisture free in order to preclude failure due to arcing or flashover. A standard practice for removing moisture from ceramic insulators is to bake the insulators at elevated temperatures under vacuum conditions. While still under vacuum, an anti-arcing coating is applied to the insulator. Such anti-arcing compounds usually consist of an acrylic polymer dissolved in a solvent, several varieties of which are commercially available.
Many ceramics are, however, temperature or pressure sensitive. High temperature baking under vacuum is not feasible for removing traces of moisture from such ceramics. Furthermore, drying under vacuum below the ceramic's temperature limit has proven insufficient when high voltage service is intended. It appears that residual water from the ceramic crystals diffuses into the anti-arcing coating and causes failure of the coating interface at high voltage conditions.
Additionally, most anti-arcing coatings are rather brittle and thus do not have good impact resistance. Furthermore, there is presently no effective means for readily determining the presence of large amounts of residual moisture in the ceramic component.
Accordingly, one object of the present invention is to improve the anti-arcing capability of high voltage ceramic insulators which are temperature or pressure sensitive.
Another object of this invention is to prevent high voltage failure of ceramic insulators due to residual moisture in the ceramic material.
A further object of this invention is to chemically tie up residual water in high voltage ceramic components by incorporating a moisture active material in an anti-arcing coating applied to the surface of such components.
A still further object of this invention is to reduce the brittleness of the anti-arcing coating applied to high voltage ceramic insulators.
Yet anther object of this invention is to visually indicate the presence of high levels of moisture in high voltage ceramic insulators when the anti-arcing coating is applied.
Still another object of this invention is to provide a method for improving the anti-arcing characteristic of high-voltage ceramic insulators which cannot be baked at elevated temperatures to remove trace amounts of moisture.
Yet a further object of this invention is to provide a high-voltage ceramic insulator which is highly resistant to arcing without the usual bake drying at elevated temperatures.
The above and other objects are realized by a moisture absorbing, anti-arcing compound applied to the surface of a high voltage ceramic insulator. This compound is formed by intermixing an isocyanate resin with a generic anti-arcing compound of the type comprising an acrylic polymer dissolved in a solvent. The isocyanate resin combines with the solvent to form a moisture active agent which chemically ties-up residual moisture in the ceramic, thereby preventing diffusion into the anti-arcing coating.
Other advantages and novel features of the invention will become apparent from the detailed description of the invention which follows.
The preferred embodiment of a composition according to this invention incorporates a hydrophilic organic material in a generic anti-arcing compound. Such compounds generally consist of an acrylic polymer dissolved in a solvent. Typical solvents used are toluene and methyl-ethyl-ketone (MEK).
Certain isocyanate-terminated prepolymers or isocyanate resins will react with water to form other anhydrous compounds. The inventors have discovered that by intermixing such isocyanate resins with the anti-arcing coating before applying the coating to a ceramic insulator, residual moisture in the ceramic is tied up chemically and thus will not degrade the electrical properties of the anti-arcing compound. Toluene diisocyanate and 4,4'-diphenylmethane diisocyanate (bis-methylene diisocyanate) are examples of the moisture active agent formed by addition of the isocyanate resins.
The isocyanate resin may be mixed in with the anti-arcing compound prior to application. The proportion of isocyanate resin to be added should be on the order of 1% or more. Although larger proportions will result in greater moisture absorbability, there is a point at which the dielectric strength of the composition will begin to degrade. The upper limit on the amount of isocyanate resin to be used is thus a function of the dielectric strength degradation which can be tolerated for a given application. Once an acceptable level of dielectric strength is selected for a given application, then the maximum amount of isocyanate resin can be readily determined. The exact relation between the two parameters can be easily determined by experiment. This will of course vary depending on the manufacturer and grade of the anti-arcing coating as well as the isocyanate resin.
The process for applying the composition would comprise the standard steps of cleaning the surface with a surfactant and then drying under vacuum conditions. The moisture absorbing, anti-arcing coating may then be applied by either dipping, brushing-on, or spraying. The entire process may be done at room temperature or at any temperature above 30° F., but within the temperature limit of the particular ceramic material.
In addition to the moisture absorbing function the isocyanate resin will also act as an external plasticizer to reduce the normal brittleness of the anti-arcing compound. The impact resistance of the coating should thereby be improved.
Furthermore, if large amounts of water are present, the isocyanate prepolymer will generate visible bubbles which would readily indicate the existence of such moisture. Such visual indication would prevent use of ceramics having retained moisture levels which are greater than the isocyanate prepolymer could handle.
Some of the advantages and new features of the subject invention should now be apparent in view of the foregoing description. For example a moisture absorbing, anti-arcing composition has been described which may be applied to the surface of a high voltage ceramic insulator. The moisture absorbing component reacts with residual moisture in the ceramic material and thus prevents it from diffusing into and degrading the anti-arcing component. An improved ceramic insulator is thereby provided.
Numerous modifications and variations of the subject invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
Claims (14)
1. An improved coating composition for ceramic electrical insulators, the coating composition being of the type having an acrylic resin dissolved in a solvent, wherein the improvement comprises: isocyanate containing material selected from the group consisting of isocyanate-terminated prepolymers and monomeric isocyanates intermixed with the acrylic resin solution in a proportion sufficient to provide maximum moisture absorbability without degrading the dielectric strength of the electrical insulating coating below a selected limit.
2. The coating composition of claim 1 wherein the isocyanate containing material is a moisture-active agent selected from the group consisting of toluene diisocyanate and 4,4'-diphenylmethane diisocyanate.
3. The coating composition of claim 2 wherein the isocyanate containing material on the order of 1% or more of the coating composition.
4. A method for improving the anti-arcing characteristic of a high voltage ceramic insulator containing trace amounts of moisture, comprising the steps of:
cleaning the ceramic insulator by applying a surfactant thereto;
drying the cleaned insulator; and
applying a moisture absorbing, anti-arcing coating to the dried insulator.
5. A method as recited in claim 4 wherein the moisture absorbing, anti-arcing coating comprises:
an anti-arcing coating; and
an isocyanate resin intermixed with the anti-arcing coating in an amount sufficient to provide an optimum balance between the moisture absorbability and the dielectric strength of the moisture absorbing, anti-arcing coating.
6. A method as recited in claim 5 wherein the anti-arcing coating comprises an acrylic polymer dissolved in a solvent, said solvent selected from the group consisitng of toluene and methyl ethyl ketone.
7. A method as recited in claim 6 wherein the isocyanate resin is selected from the group consisting of toluene diisocyanate and bis-methylene-diisocyanate.
8. A method as recited in claim 7 wherein the amount of the isocyanate resin intermixed is at least 1% of the amount of the anti-arcing coating.
9. A method as recited in claim 8 wherein all of the steps are performed at room temperature.
10. Apparatus for insulating an energized high voltage conductor comprising in combination:
a ceramic member disposed between said high voltage conductor and ground; and
a moisture absorbing, anti-arcing composition coated on said ceramic member.
11. Apparatus as recited in claim 10 wherein the moisture absorbing, anti-arcing composition comprises:
an anti-arcing coating; and
an isocyanate resin intermixed with the anti-arcing coating in an amount sufficient to provide an optimum balance between the moisture absorbability and the dielectric strength of the moisture absorbing, anti-arcing coating.
12. Apparatus as recited in claim 11 wherein the isocyanate resin comprises toluene diisocyanate.
13. Apparatus as recited in claim 11 wherein the isocyanate resin comprises bis-methylene-diisocyanate.
14. In the combination of a ceramic insulator and an acrylic resin composition present as an anti-arc coating disposed thereon, the improvement which comprises:
isocyanate containing materials intermixed with the resin composition, the materials being selected from the group consisting of isocyanate-terminated prepolymers and monomeric isocyanates.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/596,786 USH555H (en) | 1984-04-04 | 1984-04-04 | Moisture absorbing anti-arcing coating and method for applying same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/596,786 USH555H (en) | 1984-04-04 | 1984-04-04 | Moisture absorbing anti-arcing coating and method for applying same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| USH555H true USH555H (en) | 1988-12-06 |
Family
ID=24388695
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/596,786 Abandoned USH555H (en) | 1984-04-04 | 1984-04-04 | Moisture absorbing anti-arcing coating and method for applying same |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | USH555H (en) |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3376252A (en) | 1965-05-27 | 1968-04-02 | Dow Chemical Co | Urethane coating compositions |
| US3798186A (en) | 1968-03-21 | 1974-03-19 | Takenaka Komuten Co | Composition for plugging formations having pores in constructive works |
| US3933760A (en) | 1974-04-19 | 1976-01-20 | Desoto, Inc. | Low temperature curing corrosion resistant polyurethane coatings |
| US3963632A (en) | 1968-12-17 | 1976-06-15 | Tokyo Shibaura Denki Kabushiki Kaisha | Insulating compositions |
| US3985688A (en) | 1972-05-18 | 1976-10-12 | Minnesota Mining And Manufacturing Company | Poly (urethane-urea) foam sealants for underground application and fluid precursors |
| US4011168A (en) | 1974-05-06 | 1977-03-08 | Dow Corning Corporation | Arc track resistant composition |
| US4069357A (en) | 1976-11-09 | 1978-01-17 | The United States Of America As Represented By The United States Department Of Energy | Process for diffusing metallic coatings into ceramics to improve their voltage withstanding capabilities |
| US4177322A (en) | 1978-04-28 | 1979-12-04 | Dow Corning Corporation | Method of improving high voltage insulating devices |
| US4234468A (en) | 1976-04-29 | 1980-11-18 | Hoechst Aktiengesellschaft | Copolymer solution consisting of acrylic resin, process for its manufacture and the use thereof in reactive lacquers |
| US4263161A (en) | 1977-12-01 | 1981-04-21 | Gottlieb Bartak | Liquid for waterproofing a masonry structure |
| US4282333A (en) | 1979-01-29 | 1981-08-04 | The Furukawa Electric Co., Ltd. | Polyolefin series resin composition for water-tree retardant electric insulation |
-
1984
- 1984-04-04 US US06/596,786 patent/USH555H/en not_active Abandoned
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3376252A (en) | 1965-05-27 | 1968-04-02 | Dow Chemical Co | Urethane coating compositions |
| US3798186A (en) | 1968-03-21 | 1974-03-19 | Takenaka Komuten Co | Composition for plugging formations having pores in constructive works |
| US3963632A (en) | 1968-12-17 | 1976-06-15 | Tokyo Shibaura Denki Kabushiki Kaisha | Insulating compositions |
| US3985688A (en) | 1972-05-18 | 1976-10-12 | Minnesota Mining And Manufacturing Company | Poly (urethane-urea) foam sealants for underground application and fluid precursors |
| US3933760A (en) | 1974-04-19 | 1976-01-20 | Desoto, Inc. | Low temperature curing corrosion resistant polyurethane coatings |
| US4011168A (en) | 1974-05-06 | 1977-03-08 | Dow Corning Corporation | Arc track resistant composition |
| US4234468A (en) | 1976-04-29 | 1980-11-18 | Hoechst Aktiengesellschaft | Copolymer solution consisting of acrylic resin, process for its manufacture and the use thereof in reactive lacquers |
| US4069357A (en) | 1976-11-09 | 1978-01-17 | The United States Of America As Represented By The United States Department Of Energy | Process for diffusing metallic coatings into ceramics to improve their voltage withstanding capabilities |
| US4263161A (en) | 1977-12-01 | 1981-04-21 | Gottlieb Bartak | Liquid for waterproofing a masonry structure |
| US4177322A (en) | 1978-04-28 | 1979-12-04 | Dow Corning Corporation | Method of improving high voltage insulating devices |
| US4282333A (en) | 1979-01-29 | 1981-08-04 | The Furukawa Electric Co., Ltd. | Polyolefin series resin composition for water-tree retardant electric insulation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1096525A (en) | Two-part pourable reactive prepolymeric dielectric encapsulant | |
| US5177143A (en) | Method of making heat stable polymeric gelloid composition | |
| US4600261A (en) | Apparatus and method for protection of electrical contacts | |
| CA1295766C (en) | Heat stable polymeric gelloids | |
| US3733426A (en) | Method and material for reclaiming waterlogged telephone cable and the like | |
| ES2132684T3 (en) | PRODUCT FOR COATING WITH AT LEAST THREE COMPONENTS PROCEDURE FOR ITS PREPARATION AS WELL AS ITS USE. | |
| US3762953A (en) | Composition and method for stripping polyvinyl butyral primed coating | |
| JPS5819354A (en) | Composition for coating electric wire and contact | |
| USH555H (en) | Moisture absorbing anti-arcing coating and method for applying same | |
| US5736190A (en) | Exterior protective layer for an electrical component | |
| EP0133785B1 (en) | Wire coating composition for restoration of polyethylene insulation | |
| US4369269A (en) | Conductive ink | |
| JPS6155521B2 (en) | ||
| US4960641A (en) | Stranded insulated wire | |
| DE2308784A1 (en) | POLYMER BLEND AND ITS USE FOR INSULATING THE STRANDS IN CABLES | |
| DE19503284A1 (en) | Impregnating material for mineral substrates | |
| EP0749128A2 (en) | Filling compound for use in cables and spliced cable connectors | |
| US3981947A (en) | Method for reclaiming waterlogged plastic insulated conductor cable | |
| US4137211A (en) | Wire coating solution | |
| JPH083544A (en) | Water repellent treatment agent and surface water repellent treatment member | |
| US4215174A (en) | Insulating coating for transformer wires | |
| EP0391183B1 (en) | Electrical insulator | |
| JP3140722B2 (en) | Butyl rubber adhesive composition and adhesive tape or sheet using the same | |
| US3708448A (en) | Coating composition | |
| RU2034884C1 (en) | Composition for coating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: UNITED STATES OF AMERICA, AS REPRESENTED BY THE SE Free format text: ASSIGNS THE ENTIRE INTEREST SUBJECT TO LICENSE RECITED;ASSIGNORS:RITTER, CATHERINE A.;KREPS, ROBERT W.;REEL/FRAME:004247/0343;SIGNING DATES FROM 19840207 TO 19840209 |
|
| STCF | Information on status: patent grant |
Free format text: PATENTED CASE |