Title of Invention

A PROCESS FOR MANUFACTURING AN INSULATING AND THERMALLY CONDUCTING TAPE & TAPE MANUFACTURED THEREOF

Abstract

A process for manufacturing "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic-Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" comprises of the following steps :- (i) coating the polyimide film with an adhesive on one side With a required deposition of 10 to 30 gm per sq.m using conventional coating methods followed by drying in conventional equipments and laminating to ceramic paper to get the duplex composite; (ii) Coating the said polyimide film side of the said duplex composite with an adhesive having required composition of 10 to 30 gm per sq. m by using conventional coating method followed by drying in conventional equipments and laminating to ceramic paper to get the triplex composite ; (iii) Coating the ceramic side of the said duplex composite obtained in step (i) with a release coating, alternatively, coating one ceramic side of the said triplex composite obtained in step (ii) with a release coating, followed by drying at temperatures of 150° -160° C using conventional equipments to get the final product;

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See Section 10) "A PROCESS FOR MANUFACTURING AN INSULATING AND THERMALLY CONDUCTING TAPE AND TAPE MANUFACTURED THEREOF". PRS Solutions Private Limited, a Company incorporated under the Companies Act, 1956 and having its office at 63, Bombay Samachar Marg, Mumbai - 400 001 Maharashtra State, India. The following specification particularly describes the nature of this invention and the manner in which it is to be performed 1 8-9-2004 FIELD OF THE INVENTION : The invention relates to "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic-Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" and the process of manufacturing the same. It consists of Ceramic Polyimide film composite in duplex form or ceramic. Polyimide film ceramic composite in triplex form with a release coating on ceramic side which helps in the ease of application. DESCRIPTION OF THE PRIOR-ART : , Presently a lot of insulating composites are used as a slot insulation for motors and coils. Some of them are (i) Aramide Paper - Polyimide film - Aramide Paper (ii) Aramide Paper (iii) Aramide Paper- Polyester film -Aramide Paper (iv) Polyimide film etc. None of them have the dual properties of insulating as well as thermally conducting. Electrically insulating and thermally conducting material developed in this invention having an additional feature of release coat ensures that the insulating paper does not stick to the slot when taken out for rewinding process. i INVENTION: This is a unique innovative electrical insulation product having high inorganic content, thereby displaying high thermal endurance capabilities. This electrical insulation is a composite of ceramic-Polyimide film or ceramic - polyimide film - ceramic with the release coating on one side (ceramic side). -2 This composite is typically used for slot insulation of Motors, alternators, Generators, Coils etc. It has high amount of Electrical strength, tensile strength and exhibits good mechanical properties. The most unique feature is that it is electrically insulating and thermally conducting. 1) Thermal conductivity 25% higher than that of conventional Aramide Paper-Polyimide - Aramide Paper based laminates. 2) Moisture Absorption 50% that of conventional based Aramide Paper -Polyimide-Aramide Paper based laminates. 3) Moisture content 75% that of conventional based Aramide Paper - Polyimide-Aramide Paper based laminates. The release coat on one side of this composite ensures that the insulating paper does not adhere to copper conductor and thus the conductor can be easily taken from the slot. This composite also exhibits good porosity, thereby ensuring that the varnish flowing into the coils is absorbed and retained by the insulating paper, thus providing the copper conductor with the requisite environmental protection. SUMMARY OF THE INVENTION : The laminate was prepared by laminating ceramic paper on one or both sides of polyimide film using room temperature drying polyurethane adhesive. The thickness of the ceramic paper was used as per the needs of the final laminate thickness ranging from 2.5 to 10 mil and the same applies for polyimide film ranging from 1.0 mil to 3.0 mil. The high temperature resistant laminating adhesive was used after suitably formulating various ingredients commonly available in market, based on polyurethane and isocyanate, keeping a deposition ranging from 10 to 30 grams./sq. meter. The coating of this formulated adhesive was done using conventional coating equipments followed by drying at a temperature of 30°C maintained for 72 hours, again using conventional equipments. 3- DUPLEX COMPOSITE The polyimide film is coated with polyurethane adhesive which is dried at room temperature and then laminated to ceramic paper. The coating, drying and lamination is done as per conventional methods. The deposition of the adhesive range from 10 to 30 grams./sq. meter. The coated material is conditioned at 30° C for 72 hours for complete drying. After the drying is over, the Polyimide film - ceramic paper Duplex composite is again coated with release coating solution on the ceramic side followed by drying using conventional coating and drying equipments. Following are the steps involved in the manufacturer of duplex composite: DESCRIPTION OF THE PREFERRED EMBODIMENTS: DUPLEX COMPOSITE lllllllllllllllllllllllllllllllllllllllllllllllllllllllllll ■> Polyimide Film AAAAAAAAAAAAAAAAAAAAAA -> Laminating Adhesive lllllllllllllllllllllllllllllllllllllllllllllllllllllllllll^ Ceramic Paper lllllllllllllllllllllllllllllllllllllllillllllllllllllllll -» Release Coating DUPLEX COMPOSITE The polyimide film is coated with polyurethane adhesive which is dried at room temperature and then laminated to ceramic paper to get triplex composite. The coating, drying and lamination is done as per conventional methods. The deposition of the adhesive range from 10 to 30 grams./sq. meter. TRIPLEXCOMPOSITE The film side of the duplex composition is again coated with polyurethane adhesive which is dried at room temperature and then laminated to ceramic paper. The coating, drying and lamination is done as per conventional methods. The deposition of the 4 adhesive range from 10 to 30 grams./sq. meter. The coated material is conditioned at 30 C for 72 hours for complete drying. Following are the steps involved in the manufacturer of triplex composite: TRIPLEX COMPOSITE llllllllllllllllllllllllllllllllllllllllllllllllllllllllllll -> Ceramic Paper AAAAAAAAAAAAAAAAAAAAAAA -> Laminating Adhesive lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll^ Polyimide Film AAAAAAAAAAAAAAAAAAAAAAA -> Laminating Adhesive lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll-* Ceramic Paper llllllllllllllllllllllllllllllllllllllllllllllllllllllllllll* Release Coating The release coating given on one side was suitably selected, keeping in mind the end application and the type of varnish used in the motor, from a range of release agents like silicones, carbamates, fluorocarbons and fluorosilicones. The coating was done using conventional coating equipments and followed by drying at high temperatures ranging from 130° C to 200° C, in line with the chemistry of the release agent, again using conventional drying equipments. The final product was then slit to size as required for the intended application using conventional slitting machines. Product Features: • Physically tough • Excellent dielectric properties. • Good thermal conductivity. Applications: • Slot cell, phase and wedge insulation for Motors and Generators. • End Laminates. • Wire and Cable wrap • Breaker panels • Bus bar insulation • Capacitor insulation • DC field coil insulation • Current carrying and wire devices. Characteristics:- • This composite provides excellent dielectric barrier. • They exhibit excellent resistance to tear initiation and tear propagation in both the machine direction and across the machine direction. • Good tensile strength and elongation properties ensure absorption of stress incurred in heavy duty winding applications. • The inorganic content in this composite over coating provides resistance to hot cut-through in high stress areas. • High thermal conductivity promotes cooler running equipment, leading to longer insulation life, better reliability and more efficient use of power. • This composite is non-hygroscopic and exhibit low moisture absorption, thus reducing need for extended drying cycles prior to varnishing or encapsulation. - 6- WE CLAIM : 1. A process for manufacturing "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic-Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" comprises of the following steps :- (i) coating the polyimide film with an adhesive on one side With a required deposition of 10 to 30 gm per sq.m using conventional coating methods followed by drying in conventional equipments and laminating to ceramic paper to get the duplex composite; (ii) Coating the said polyimide film side of the said duplex composite with an adhesive having required composition of 10 to 30 gm per sq. m by using conventional coating method followed by drying in conventional equipments and laminating to ceramic paper to get the triplex composite ; (iii) Coating the ceramic side of the said duplex composite obtained in step (i) with a release coating, alternatively, coating one ceramic side of the said triplex composite obtained in step (ii) with a release coating, followed by drying at temperatures of 150° -160° C using conventional equipments to get the final product; 2. A process for manufacturing "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic- Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" as claimed in Claim 1, wherein the adhesive is based on polyurethane and isocyanate. 3. A process for manufacturing "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic-Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" as claimed in Claims 1 and 2, wherein the release coating is based on silicones, organic carbamates, fluorocarbon or fluorosilicone. 4. "An Insulating And Thermally Conducting Tape Containing (a) Ceramic-Polyimide Film Duplex Composite or (b) Ceramic-Polymide Film-Ceramic Triplex Composite Having Release Coating For Electrical Insulation" is obtained by process as claimed in Claims 1 to 3 above. Dated this 11th day of January, 2003 (BhaMS. Shah) Duly Constituted Attorney

Documents:

48-mum-2003-cancelled pages(8-9-2004).pdf

48-mum-2003-claims(granted)-(8-9-2004).doc

48-mum-2003-claims(granted)-(8-9-2004).pdf

48-mum-2003-correspondence(2-11-2004).pdf

48-mum-2003-correspondence(ipo)-(27-9-2006).pdf

48-mum-2003-form 1(14-1-2003).pdf

48-mum-2003-form 19(17-7-2003).pdf

48-mum-2003-form 2(granted)-(8-9-2004).doc

48-mum-2003-form 2(granted)-(8-9-2004).pdf

48-mum-2003-form 26(14-1-2003).pdf

48-mum-2003-form 3(14-1-2003).pdf

48-mum-2003-form 5(14-1-2003).pdf