FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10)
"FLAME RETARDANT TRANSFER ADHESIVE TAPE" AND THE METHOD OF MANUFACTURING THE SAME".
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, India.
The following specification particularly describes the nature of this invention and the manner in which it is to be performed.

FIELD OF THE INVENTION:
This invention relates to "Flame retardant transfer adhesive tape" and the process of manufacturing the same. The said tape is self adhesive tape which is flame retardant, rubber based and does not have any backing material to carry the adhesive. Instead of a backing material, a release liner is used as carrier of adhesive. The said liner may be paper or film.
DESCRIPTION OF THE PRIOR ART:
Both sides adhesive coated tapes commonly known as double faced tapes or double sided tapes are used to splice materials from an end of one roll to a start of the next roll in industries where a web of material is fed continuously to some operation . They are also used for applications like mounting of name plates, lamination, disposable sandpaper pads, & tags. These tapes are available in plenty in the market.
Double sided pressure sensitive adhesive tapes are obtained by coating pressure sensitive adhesive on cloth or film or non woven or other materials as supporting / backing material. Thin double faced tapes are usually based on thin polyester or polypropylene films or tissue paper or non woven material as supporting material. Where thickness of the supporting material is to be avoided transfer adhesive tapes provide a wonderful alternative to double sided tapes.
Transfer adhesive tapes consist of an unsupported adhesive coating applied over a release coated liner. The release liner used must have a sufficient differential release property in order to retain the adhesive on the side to which it was originally applied. At the same time the release level, however, must be sufficiently low to allow a good adhesive transfer. These tapes are especially useful in providing the adhesive in the exact location for later use. Removal of the release liner exposes the adhesive & makes it available for lamination to the second surface.

In transfer adhesive tapes the pressure sensitive adhesive used is often acrylic, however, transfer adhesive tapes with rubber - resin adhesives are also available. Flame retardant rubber based transfer adhesive tape in the form of a thin flame retardant adhesive layer, without supporting material is a special feature not available in other tapes. In the present invention an attempt has been made to develop a transfer adhesive tape without the use of any supporting material and using a rubber based pressure sensitive adhesive which is flame retardant.
SUMMARY OF THE INVENTION:
"Flame retardant transfer adhesive tape" (hereinafter called "FR TAT") is a pressure sensitive self adhesive tape which is in the form of a thin adhesive layer applied on both side release coated paper or film (Liner) which acts as carrier. The said FR TAT is flame retardant and is without any supporting material. The adhesive is based on rubbers, flame retardant additives, fillers, tackifiers & anti-oxidants. Thus in FR TAT, the thin adhesive layer will help to make both sides tacky tape and on the other hand flame retardancy of the tape will guard against fire hazards.
The said flame retardant transfer adhesive tape can also be used to make different types of single sided and/or double sided flame retardant adhesive tapes by applying the adhesive layer of FR TAT on one side or both sides of any supporting material like tissue paper, cloth , non woven & film. The said FR TAT will have a wide ranging applications for making varities of printed labels, where flame retardancy is a desired feature, by application of FR TAT on the printed side of the label subsequent to the printing operation on a suitable substrate such as Polyester film, Polycarbonate film etc.
INVENTION:
A manufacturing of "Flame retardant transfer adhesive tape" consists of coating a formulated pressure sensitive adhesive, formulated to impart the required flame retardancy from a blend of natural and synthetic rubbers, on one side of a liner having release coating on both sides and having sufficient differential release in order to retain

the adhesive on the side to which it was originally coated, followed by drying and slitting to obtain the tape in desired length and width.
The process of applying the pressure sensitive flame retardant adhesive is done by conventional method of coating equipment followed by using known drying methods. The said tape is then slit in desired length and width.
The formulated pressure sensitive flame retardant adhesive is manufactured by blending various materials comprising natural and/or synthetic rubbers, tackifying resins of natural/synthetic type, fillers like oxides and/or hydroxides of metal, naturally occurring minerals, halogenated organic/inorganic compounds, and followed by solvating with hydrocarbon/ aromatic solvents to form a compound of coatable consistency and texture commensurate to the coating equipment.
The adhesive of this invention comprises of elastomeric components, tackifiers, fillers, antioxidants, flame resistant additives etc..
The elastomeric component comprises of two parts (I) one or more of the natural rubbers like RMA-1, RMA-II, RMA-III, RMA-IV, PLC of various grades and (ii) at least one of the synthetic rubbers such as, but not limited to, Styrene-Isoprene-Styrene (SIS), Styrene- Butadyene- Styrene (SBS), Styrene Butadyene Rubber (SBR), VITON, Polychloroprene etc.
The adhesive of the present invention contains one or more of tackifiers which can be formed of hydrocarbon resins, rosin and rosin derivatives, polyterpenes, coumarone-indene resins, any compatible conventional tackifier or mixtures thereof. The resins can be modified with alpha methyl styrene. It has been found that a mixture of resins can provide a better balance of properties than any one resin alone.
The adhesive of this invention contains fillers which can be formed of calcium carbonate, barytes, aluminum hydroxide, zinc oxide, clay, and mixtures thereof in order to extend the adhesive and alter its appearance.

The adhesive of this invention contains flame retarding ingredients which can be formed of antimony tri oxides, halogenated organic/inorganic compounds, any compatible conventional flame retardant compounds or mixtures thereof in order to make the adhesive flame retardant.
The adhesive of this invention contains small amounts of other additives such as antioxidants, heat stabilizers, pigments and the like. Antioxidants and heat stabilizers are to be used for improved heat stability of the adhesive. Typical antioxidants are 2,5 ditertiary amyl hydroquinone, di-tertiary butyl cresol and amines. At least one of the -conventional heat stabilizers such as Zinc salts of alkyl di-thiocarbomates are used in the present invention. Coloured pigment are added to obtain a coloured adhesive.
The release liner used in this invention is a both side release coated paper or film which has sufficient differential release in order to retain the adhesive on the side to which it was originally coated. The release level, however, is sufficiently low to allow a good transfer of flame retardant adhesive from the surface of the release liner to the desired substrate during use. The release coating solution for coating paper or film used in this invention is based on Silicone or Fluorosilicone or carbamates & similar materials having property of releasing adhesive from the surface.
A process of manufacturing "Flame retardant transfer adhesive tape" renders ease of application especially useful in providing the adhesive in the desired location for later use. Removal of the release paper exposes the adhesive & makes it available for lamination, wherein the tape provides additional, protection against the spread of fire at the place of application. This flame retardant transfer adhesive tape can be also be used to make different types of double sided flame retardant adhesive tapes by applying the adhesive layer of FR TAT on both sides of the backing material like tissue paper, cloth , non woven & film. Yet another use of this FR TAT will be for making varities of printed labels, where flame retardancy is a desired need, by application of a layer of FR TAT on the printed side of the label subsequent to the printing operation on a suitable substrate such as Polyester film, Polycarbonate film etc.

This combination provides ease of application along with the advantage of lower thickness of tape in absence of any supporting material and also safe guards against fire hazards.
DESCRIPTION OF THE PREFERRED EMBODIMENTS :CONSTRUCTION:
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIHI Differential release silicone paper or Film
IIIIIIIIIIIHIIIIIIIIIIHIIIIIIIIIIIIIIIIIIIIIIII Flame retardant rubber based adhesive

WE CLAIM:
1. "A process of manufacturing Flame retardant transfer adhesive tape comprises of the
following steps:-
(a) Coating of formulated flame retardant rubber based pressure sensitive adhesive on one side of a liner having release coating on both sides to get flame retardant tape ;
(b) in the above step the said adhesive is coated in a conventional method and thereafter dried by known method;
(c) the said tape is cut in desired length and width;

2. "A process of manufacturing Flame retardant transfer adhesive tape" as claimed in Claim 1, wherein the formulated pressure sensitive adhesive is manufactured by blending various materials comprising of but not limited to elastomeric polymers, tackifying resins of natural/synthetic type, fillers like oxides and/or hydroxides of metal, naturally occurring minerals, flame retardent compounds, additives and followed by solvating with hydrocarbon /aromatic solvents to form a compound of coatable consistency and texture commensurate to the coating equipment;
3. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein the elasomeric polymers used is a combination of (i) one or more of the natural rubbers like RMA-1, RMA-II, RMA-III, RMA-IV, PLC of various grades and (ii) at least one of the synthetic rubbers such as, but not limited to, Styrene-Isoprene-Styrene (SIS), Styrene- Butadyene- Styrene (SBS), Styrene Butadyene Rubber (SBR), VITON, Polychloroprene;.
4. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein the tackifiers comprise one or more of tackifiers which can be formed of hydrocarbon resins, rosin and rosin derivatives, polyterpenes, coumarone-indene resins, any compatible conventional tackifier or mixtures thereof and the said resins can be further modified with alpha methyl styrene;

5. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in
Claim 2 wherein fillers can be formed of calcium carbonate, barytes, aluminum
hydroxide, zinc oxide, clay, and mixtures thereof;
6. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein the flame retarding compounds can be formed of antimony tri oxides, halogenated organic/inorganic compounds, any compatible conventional flame retardant compounds or mixtures thereof;
7. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein antioxidants are 2,5 ditertiary amyl hydroquinone, di-tertiary butyl cresol and amines;
8. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein at least one of the -conventional heat stabilizers such as Zinc salts of alkyl di-thiocarbomates are used in the present invention;
9. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein the said additive comprises of coloured pigment which is used to incorporate required colour to the adhesive;

10. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 2 wherein required quantity of organic solvents such as hydrocarbon/ aromatic solvents, more specifically any one or mixture of Toluene, Hexane, Heptane etc. is used to form a compound of coatable consistency and texture commensurate to the coating equipment;
11. "A process of manufacturing flame retardant transfer adhesive tape" as claimed in Claim 1 wherein the release paper or film used has sufficient differential release in order to retain the adhesive on the side to which it was originally coated;

12. A process of manufacturing Flame retardant transfer adhesive tape" as claimed in
Claim 1 wherein the adhesive coating, drying and slitting of FR TAT is done by
conventional methods and equipments used in the industry;
13. A process of manufacturing "Flame retardant transfer adhesive tape" as claimed in
Claims 1 to 12 above whereby a "Flame retardant transfer adhesive tape" is obtained.
Dated this 27th day of September, 2007