FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10)
Reflective Aluminized Glass Fabric Tape For Thermal Insulation Of Hot Pipes And The Process 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.
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 'Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process for manufacturing the same. The said reflective aluminized glass fabric tape is used for thermal insulation of hot pipes, which provides protection against both thermal and rediative construction of energy. The said tape is easily installed, capable of easily fitting multiple substrate diameters, space-saving, lightweight, and durable. One of the application for this tape, but not limited to, is for minimising the loss of heat from the working fluid to the surrounding environment to save energy and cost by thermal insulation of pipe lines carrying fluids where the liquid is required to be maintained at a optimum temperature.
DESCRIPTION OF THE PRIOR-ART :
Thermal insulation is the most preferred method of preventing heat energy from escaping a hot object to another surface or surrounding which is at a lower temperature. In other words, a suitable thermal insulation system is used to keep the contents in an enclosed area such as a pipe line at a optimum temperature. Such thermal insulation systems help in preventing heat transfer from the contents of the pipe line to atmosphere and vice versa thereby maintaining the optimum temperature of the fluid flowing inside the pipeline which is required to keep the fluid from freezing at low temperature and degrading at high temperatures. Heat is transferred from one material to another by conduction, convection and/or radiation. Insulators are used to minimize that transfer of heat where two objects in vicinity are at different temperatures.


The term thermal insulation can refer to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. While reflectors are used to reduce radiative heat transfer, foams, fibrous materials or air spaces are used to reduce conductive and convective heat transfer by reducing physical contact between objects and by reducing movement of gases around the insulated object respectively. Combinations of some of these methods are often used to increase the efficiency of thermal insulation.
Many different materials can be used as insulators. Many organic insulators are made from petrochemicals and recycled plastic. Many inorganic insulators are made from recycled materials such as glass (e.g. glass wool). Most insulators in common use rely on the principle of trapping air to reduce convective heat transfer. These insulators can be fibrous (e.g. asbestous), cellular (e.g. cork or plastic foam), or granular (e.g. sintered refractory materials). Standard types of insulation, such as fiberglass, asbestos, plastic foam, and cellulose primarily reduce heat transfer by trapping air or some type of a gas. Thus, these products or technologies reduce convection as a primary method of reducing heat transfer.
Most of the thermal insulating materials used for insulating hot pipelines carrying fluids are fibrous and/or foams. These substances, while perform well for reducing heat transfer, are soft and loose thereby making them susceptible to physical damage by external factors such as physical abrasion, wind, sunrays, rains etc. and require protection in the form of outer covering. General practice in the industry is to use metal nets or claddings as outer wrap to keep thermal insulating materials in place as well as to protect them from


any external agency as described above. These claddings, however, have few shortcomings such as (a) they can not prevent ingress of water, dust, moisture , rodents etc. in the insulation material / system thereby reducing insulation efficiency, (b) they are formed by bending sheet metal inducing inherent stress because of which they tend to come back to the original position resulting into opening of the joints.
SUMMARY OF INVENTION
In the present invention an attempt has been made to prepare a Reflective aluminized glass fabric tape for thermal insulation of hot pipes which is suitable for use as an outer wrap in any thermal insulation system used for insulating hot pipes. The said Reflective aluminized glass fabric tape for thermal insulation of hot pipes when applied on pipe lines as per recommended installation procedure described herein facilitates retention of optimum temperature of the contents inside the pipes by substantially reducing heat loss to the surrounding atmosphere by all three modes of heat transfer viz. Conduction, Convection and Radiation.
Reflective aluminized glass fabric tape for thermal insulation of hot pipes disclosed, as one of the preferred embodiments of the present invention is a super soft Aluminium foil- woven glass fabric pressure sensitive adhesive tape having silicone adhesive on the glass fabric side. The silicone adhesive side of the tape is protected by lamination of polymeric film liner such as Poly vinyl chloride (PVC), High density polyethylene (HDPE) , Poly ethylene terepthalate (PET) etc. which may


be having a release coating or a embossed texture or a raised pattern on at least one of the sides.
In another embodiment of the present invention is a super soft Aluminium foil- woven glass fabric pressure sensitive adhesive tape having acrylic adhesive on the glass fabric side. The acrylic adhesive side of the tape is protected by laminating a polymeric film liner such as Poly vinyl chloride (PVC), High density polyethylene (HDPE), Low density polyethylene (LDPE), high density high molecular weight (HMHD), Bi-axially oriented polypropylene (BOPP), Poly ethylene terepthalate (PET) etc. which may be having a release coating or a embossed texture or a raised pattern on at least one of the sides or paper liner such as Glassine, Kraft, polycoated bleached kraft etc. which may be having a silicone resin coating on at least one of the sides.
For one of the preferred embodiment (figure 1) the process of manufacturing of the Reflective aluminized glass fabric tape for thermal insulation of hot pipes comprises of (a) coating of pressure sensitive silicone adhesive with a deposition of 10 to 25 g/m2 on non-glossy side of soft Aluminium foil followed by drying using conventional coating and drying methods and laminating the adhesive coated side of the Aluminium foil to woven glass fabric by pressing the said foil and fabric through laminating rollers under pressure thereby obtaining an aluminized glass fabric, (b) coating of pressure sensitive silicone adhesive on the woven glass fabric side of the laminate obtained by step (a) above by use of conventional methods followed by drying operation which is also carried out by known conventional methods and lamination of polymeric film liner such as Poly vinyl chloride (PVC), High density polyethylene (HDPE) , Poly


ethylene terepthalate (PET) etc. which may be having a release coating or a embossed texture or a raised pattern on at least one of the sides in such a way so that the released coated / embossed textured /raised pattern side is in contact with the pressure sensitive adhesive coated side of aluminized glass fabric by pressing the said coated cloth and liner through laminating rollers with a minimum pressure thereby obtaining tape Reflective aluminized glass fabric tape for thermal insulation of hot pipes and (c) slitting of the composite thus obtained in step (b) to desired width and length using conventional methods of slitting.
For another embodiment (figure 2) the process of manufacturing of the Reflective aluminized glass fabric tape for thermal insulation of hot pipes comprises of (a) coating of pressure sensitive acrylic adhesive with a deposition of 10 to 55 g/m2 on glossy side of soft Aluminium foil followed by drying using conventional coating and drying methods and laminating the adhesive coated side of the Aluminium foil to woven glass fabric by pressing the said foil and fabric through laminating rollers under pressure thereby obtaining an aluminized glass fabric, (b) coating of pressure sensitive acrylic adhesive on the woven glass fabric side of the laminate obtained by step (a) above by use of conventional methods followed by drying operation which is also carried out by known conventional methods and laminating a polymeric film liner such as Poly vinyl chloride (PVC), High density polyethylene (HDPE), Low density polyethylene (LDPE), high density high molecular weight (HMHD), Bi-axially oriented polypropylene (BOPP), Poly ethylene terepthalate (PET) etc. which may be having a release coating or a embossed texture or a raised pattern on at least one of the sides in such a way so that the released coated / embossed textured /raised pattern side is in contact


with the pressure sensitive adhesive coated side of aluminized glass fabric or paper liner such as Glassine, Kraft, polycoated bleached kraft etc. or film such as Polyester, Polypropylene, Polyethylene etc. which may be having a silicone coating on at least one of the sides in such a way so that the release coated side is in contact with the pressure sensitive adhesive coated side of aluminized glass fabric by pressing the said coated tape and cloth through laminating rollers thereby obtaining tape Reflective aluminized glass fabric tape for thermal insulation of hot pipes ; alternately (Figure 3), lamination of both side coated polyester film tape with high tack pressure sensitive acrylic adhesive with siliconised paper liner to aluminized glass cloth obtained in step (a) above by pressing the said coated tape and cloth through laminating rollers in such a way that adhesive layer is in contact with aluminized glass cloth thereby obtaining tape Reflective aluminized glass fabric tape for thermal insulation of hot pipes and (c) slitting of the composite thus obtained in step (b) to desired width and length using conventional methods of slitting.
The Reflective aluminized glass fabric tape for thermal insulation of hot pipes thus obtained has the following features:
1] Useful for insulating hot pipes up to a temperature of 180°C.
2] It is highly flexible, easy to apply, light weight, less thick and
conformable hence can be applied on highly contoured surfaces.
3] Atleast one of the embodiments of this invention is flame retardant
and passes UL -94 test at V-1 level.
4] Helps in reducing fire hazard due to oil spillage on hot surfaces.
5] It is weather resistant and does not get deteriorated due to outdoor
weathering.
6] Aluminium foil having very low emittance values (typically 0.03)
significantly reduces radiative heat loss from surface.


7] No change in thermal performance due to compaction or moisture
absorption.
8] It is free of any harmful substance and does not irritate the skin,
eyes or throat and contain no substances which will out-gas.
9] It is free from any leachable chlorides hence does not cause any
corrosion on metal.
10] It provides much desirable impact resistance and puncture
resistance properties.
For maximum efficiency of the thermal insulation system of hot pipelines using Reflective aluminized glass fabric tape the recommended installation procedure involves :
(a) Application of one or more layer/s of any thermally insulating materials such as glass wool, foam, felt, blanket etc. on the outer surface of the pipe to be insulated covering the entire length of the pipe ensuring no gap followed by (b) removal of liner layer from Reflective aluminized glass fabric tape and application of tightly wound layer of Reflective aluminized glass fabric tape over entire length of insulating material in spiral winding or cigarette wrap with sufficient overlap between two consecutive layers ensuring complete coverage of insulation layer.
When thermal insulation system for hot pipes is applied on the outer surface of the hot pipes carrying fluids at high temperature as per the procedure described above it provides following benefits:
1] Maintains optimum temperature of the fluid inside the pipe
2] Reduces the possibility of human contact with heated ducts and
pipes thereby reducing the risk of injury.
3] Provides greater flexibility and impact resistance to the insulation.


4] Redction in ambient temperature around the hot pipes resulting in
better working condition.
5] Avoids heating of adjacent materials which can occur when the heat
released conflicts with the fluid temperature in adjacent pipes and
ducts, or affects the temperature of local materials such as cables,
plastics, paper or board products, etc.
6] Fire risk is minimized as Reflective aluminized glass fabric tape is
flame retardant.
7] Minimises the loss of heat from the working fluid to the
surrounding environment which helps save energy and cost.
8] Maintenance friendly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
Aluminium foil
Silicone pressure sensitive adhesive
Woven glass fabric
Silicone pressure sensitive adhesive
Film liner
Aluminium foil
Acrylic pressure sensitive adhesive
Woven glass fabric
Acrylic pressure sensitive adhesive
Film or paper liner
Aluminium foil
Figure 1
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Figure 2
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Figure 3 ////////////////////


11111111111111111111 Acrylic pressure sensitive adhesive
//////////////////// Woven glass fabric
11111111111111111111 Acrylic pressure sensitive adhesive
//////////////////// Polyester film
11111111111111111111 Acrylic pressure sensitive adhesive
//////////////////// Film or paper liner
~1Q-

WE CLAIM :
Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same comprises of the following steps
(a) coating of pressure sensitive adhesive on non-glossy side of soft Aluminium foil followed by drying using conventional coating and drying methods and laminating the adhesive coated side of the Aluminium foil to woven glass fabric by pressing the said foil and fabric through laminating rollers under pressure to obtain aluminized glass cloth;
(b) coating of pressure sensitive adhesive on the woven glass fabric side of the aluminized glass cloth obtained by step (a) above by use of conventional methods followed by drying operation which is also carried out by known conventional methods and lamination of polymeric film liner in such a way so that the release coated / embossed textured /raised pattern side of the said liner is in contact with the pressure sensitive adhesive coated side by pressing the said coated cloth and liner through laminating rollers or;
(c) alternately, lamination of both side coated polyester film tape with high tack pressure sensitive acrylic adhesive with siliconised paper liner to aluminized glass cloth obtained in step (a) above by pressing the said coated tape and cloth through laminating rollers in such a way that adhesive layer is in contact with aluminized glass cloth and


(d) slitting of the tape thus obtained in step (b) or step (c) above to desired width and length using conventional methods of slitting.
2. Reflective aluminized glass fabric tape of thermal insulation of hot pipes and the process for manufacturing the same claimed in Claim 1 wherein Aluminium foils used is soft foil having thickness ranging from 10 to 50 micron.
3. Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same as claimed in Claim 1 wherein pressure sensitive adhesive is made by blending silicone adhesive and organic peroxide catalysts such as Benzoyl Peroxide, 2-4 dichloro benzoyl peroxide.
4. Reflective aluminized glass fabric tape for thermal insulation of
hot pipes and the process of manufacturing the same as
claimed in Claim 1 wherein adhesive deposition is preferably 10
to 55 g/m2.
5. Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same as claimed in Claim 1 wherein the Glass fabric used is a woven glass fabric preferably having a thickness of 1 to 4 mil, however, any suitable thickness can also be used.
6. Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same as claimed in Claim 1 wherein polymeric film liner may be Poly vinyl chloride (PVC), High density polyethylene (HDPE), Low density polyethylene (LDPE), high density high molecular weight (HMHD), Bi-axially oriented polypropylene (BOPP), Poly ethylene terepthalate (PET) which may be having a release coating or a


embossed texture or a raised pattern on at least one of the sides.
7. Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same as claimed in Claim 1 wherein paper liner may be Glassine paper, Kraft paper, polycoated bleached kraft which may be having a silicone resin coating on at least one of the sides
8. Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same as claimed in Claim 1 to 7 by which Reflective aluminized glass fabric tape for thermal insulation of hot pipes is obtained.


ABSTRACT
Reflective aluminized glass fabric tape for thermal insulation of hot pipes and the process of manufacturing the same comprises of (a) coating of pressure sensitive adhesive on non-glossy side of soft Aluminium foil followed by drying and laminating the adhesive coated side of the Aluminium foil to woven glass fabric to obtain aluminized glass cloth; (b) coating of pressure sensitive adhesive on the woven glass fabric side of the aluminized glass cloth obtained by step (a) followed by drying operation and lamination of polymeric film liner in such a way so that the release coated / embossed textured /raised pattern side of the said liner is in contact with the pressure sensitive adhesive coated side by pressing the said coated cloth and liner through laminating rollers; (c) alternately, lamination of both side coated polyester film tape with high tack pressure sensitive acrylic adhesive with siliconised paper liner to aluminized glass cloth obtained in step (a) above by pressing the said coated tape and cloth through laminating rollers in such a way that adhesive layer is in contact with aluminized glass cloth and (d) slitting of the tape thus obtained in step (b) or step (c) above to desired width and length.