WO2021119374A1

WO2021119374A1 - Metalized fabric heating device for medical solutions

Info

Publication number: WO2021119374A1
Application number: PCT/US2020/064408
Authority: WO
Inventors: David Uland; Eric Howard; Kelley Terrell; Mark Beran
Original assignee: Encompass Group, Llc
Priority date: 2019-12-12
Filing date: 2020-12-11
Publication date: 2021-06-17

Abstract

There is disclosed a warming blanket having a metalized fabric exterior layer and an interior heating element made of a carbon fiber mat or carbon veil. The warming blanket includes electrodes that are formed of a conductive ink which extends through the width of the carbon veil.

Description

METALIZED FABRIC HEATING DEVICE FOR MEDICAL SOLUTIONS

REFERENCE TO RELATED APPLICATION

Applicant claims the benefit of U.S. Provisional Patent Application Serial No. 62/471,103 filed March 14, 2017 and entitled Metalized Fabric Heating Blanket. This is a continuation-in-part of U.S. Patent Application Serial Number 15/920,383 filed March 13, 2018 and entitled “Metalized Fabric Heating Blanket And Method Of Manufacturing Such”, which is a continuation-in-part of U.S. Patent Application Serial Number 15/841,044 filed December 13, 2017 and entitled “Metalized Fabric Heating Blanket”.

TECHNICAL FIELD

This invention relates generally to heating blankets, and more particularly to heating blankets utilizing metalized fabrics and the method of manufacturing such.

BACKGROUND OF THE INVENTION

Thermally insulative blankets and the like have been made for centuries. Such blankets have traditionally been made of a wool or cotton cloth. These materials have provided a certain amount of heat retaining qualities, however, they are not optimal for such a task.

It has recently been discovered that blankets and clothing may be made of a metalized material to provide the added benefit of infrared heat reflecting capabilities to better prevent heat loss from a person. These products may be used as outdoor blankets, medical patient coverings, or other clothing wherein the conservation of body heat is desired. These metalized fabrics however are usually stiff and not soft to the touch.

Encompass Group, LLC has provided a metalized fabric material under the tradename Thermoflect for many years. This metalized fabric has four discrete layers which are bonded together to form the fabric. These four layers include a clear polyethylene layer, a vaporized aluminum layer, a second polyethylene layer, and a smooth surface spunbond polypropylene layer, these layers being recited in sequence from an exterior surface to an interior surface facing a person donning an article incorporating the fabric. It would be desirous to have a metalized fabric material which is softer to the touch and less stiff to provide better draping and loft characteristics. It would also be desirous to provide supplemental heating to warm the person in a quicker and more efficient manner.

One way of providing supplemental heating is to couple electrically resistive heating elements to a blanket. As electricity is passed through the heating elements, heat is produced which is utilized to warm a person. A problem with these electric warming blankets is that they are not efficient. Another problem is that they produce uneven warming areas, as heat is concentrated in the area of the heating element.

It would be beneficial to provide a warming blanket which provides a more efficient, fast, and consistent heat to a person so that it may be more suitable for use upon a person than those of the prior art. Accordingly, it is to the provision of such that the present invention is primarily directed.

SUMMARY OF THE INVENTION

In a preferred form of the invention a heating blanket comprises a carbon veil material having a plurality of carbon fibers extending between a carbon veil first surface and a carbon veil second surface oppositely disposed from the carbon veil first surface. The heating blanket also has a first electrically conductive rail electrically coupled along a first side of the carbon veil, a second electrically conductive rail electrically coupled along a second side of the carbon veil material opposite the first side of the carbon veil material, the first and second electrically conductive rails being made of an electrically conductive ink extending through the carbon veil from the first surface to the second surface. The heating blanket also has a first electrically insulative layer overlaying a first surface of the carbon veil material, a second electrically insulative layer overlaying a second surface of the carbon veil material oppositely disposed from the first surface of the carbon veil material, and an electrical control circuit electrically coupled to the first and second electrically conductive rails. With this construction, electric current passing from the electrical control circuit to the first and second electrically conductive rails passes through the carbon veil to create heat.

In another form of the invention, a method of manufacturing a heating blanket comprises the steps of providing a carbon veil material, depositing an electrical conductive ink upon the carbon veil material to form two electrically conductive rails, forcing the electrical conductive ink of the two electrically conductive rails into the interior of the carbon veil material, coupling a first electrically insulative layer over a first surface of the carbon veil material, coupling a second electrically insulative layer overlaying a second surface of the carbon veil material oppositely disposed from the first surface of the carbon veil material, and coupling an electrical control circuit to the first electrically conductive rail and the second electrically conductive rail.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a warming blanket embodying principles of the invention in a preferred form.

Fig. 2 is a cross-sectional view of a portion of the warming blanket of Fig. 1.

Fig. 3 is a top view of a portion of the warming blanket of Fig. 1.

Fig. 4 is a plan view of the warming blanket of Fig. 1.

Fig. 5 is a plan view of a warming blanket embodying principles of the invention in another preferred form.

Fig. 6 is a cross-sectional view of a portion of the warming blanket of Fig. 5.

Figs. 7-12 are a series of top view of a warming blanket in another preferred embodiment, showing the manufacturing process.

Fig. 13 is a cross-sectional view of a portion of the warming blanket shown in Figs.

7-12.

Fig. 14 is a cross-sectional view of a portion of the carbon veil and conductive ink side rail of the warming blanket in another preferred embodiment. DETAILED DESCRIPTION

With reference next to the drawings, there is shown a warming blanket 8 made in part with a metalized fabric 10 embodying principles of the invention in a preferred form. The warming blanket 8 has a lower surface 11 which is intended to face away from a person (patient) overlaid with or donning the material and an upper surface 12 which is intended to face the person (patient). The metalized fabric includes a first layer 15 of clear thermoplastic (for example a polyethylene) material, a second layer 16 of vaporized aluminum material (solid metalized layer), a third layer 17 of thermoplastic (for example a polyethylene) material, and a fourth layer 18 of lofted billow spunbond thermoplastic (for example a polypropyl ene)non- woven material. The exterior surface of the first layer 15 constitutes the fabric lower surface 11 , while the exterior surface of the fourth layer 18 constitutes the upper surface 12.

The warming blanket 8 also includes a resistive heating portion 30 positioned between the third layer 17 and the fourth layer 18. The resistive heating portion 30 is positioned distally from the perimeter or outer edge of the warming blanket 31 and metalized fabric 10 so that a surrounding margin 32 is formed therebetween.

The resistive heating portion 30 has heater trace resistors or heating elements 34 arranged in a longitudinal array with each heating element 34 extending laterally, as best shown in Fig. 4. The heating elements 34 are formed by depositing a conventional electrically conductive ink upon the third layer 17 in the desired pattern. The heating elements 34 are electrically joined together through a pair of conductive tapes 35 coupled to the ends of the heating elements. The conductive tapes 35 may be made of a metal, such as copper, or in the alternative, the conductive tapes 35 may be replaced by additional conductive ink strips or any other configuration of a conductive element. The resistive heating portion 30 may also include a convention flat flex crimp pin type connectivity or coupler 36 to allow a quick connect to a controller 43, which may also include thermistors 37, or thermocouples, to regulate the current and temperature of the warming blanket 8.

The warming blanket 8 may have an input voltage of 100 to 250 VAC and a maximum blanket power of 7 W @12 VDC to 109 W @ 48 VDC. The metalized fabric is manufactured by joining the third layer 17 of thermoplastic material having the resistive heating portion 30 thereon to the fourth layer 18 of non- woven or spunbond thermoplastic non- woven material. The second layer 16 of vaporized aluminum material is then deposited or joined onto the third layer 17 via a vacuum deposit chamber. The first layer 15 is then extruded or joined onto the second layer 16. The combination of layers is then passed through cold calender rollers which seals the layers together in a pattern that forms a series, matrix or field of large pillowed areas or regions 20 surrounded at four sides by smaller pillowed regions 21. The large pillowed region 20 is generally oval in shape with a longitudinal length LA of approximately 3/16 of an inch and a lateral width LW of approximately 2/16 of an inch. The seals 23 themselves are non-continuous or fragmented, as they are formed by several unjoined segments 24 which also helps in providing a less stiff feel to the metalized fabric by breaking up the seals which tend to be stiffer than those areas of the fabric which are not sealed, i.e., the bonding of the material at the seals tends to stiffen the sealed areas and thereby tends to stiffen the overall material decreasing its drapability and loft. The metalized fabric of the present invention is fused, bonded or sealed on approximately 14% of the material, as opposed to the prior art material which included at a minimum 18% fusing, bonding or sealing.

It is believed that the position of the heating elements between the person and the metalized second layer 16 provides for an more even distribution of heat. Heat produced from the heating elements is reflected by the metalized second layer 16 back onto the person. Thus, heat initially drawn away from the person is not lost to ambient environment and is instead used to heat the person, a distinct advantage over the prior art.

It is believed that the pillowing of the metalized fabric provides for greater insulative qualities, a softer feel, better glare reduction, improved drapability, and improved loft.

Another discovered advantage has been the materials improved cross-direction tearing resistance. A test was conducted comparing the prior Thermoflect metalized material, previously described, to the metalized fabric of the present invention. The metalized fabric of the present invention was found to have a cross directional tearing factor of 435.7, while the prior Thermo fleet metalized material had a tested cross directional tearing factor of 393. This test shows an improvement in tearing resistance of approximately eleven percent (11%).

As an alternative to the first embodiment, a second embodiment of the invention in a preferred form is shown in Figs. 5 and 6. Here, warming blanket 40 has the previously described first layer 15, second layer 16, third layer 17 and fourth layer 18 are formed as a unitary structure. A fifth layer 41 is coupled to the fourth layer 18. The fifth layer 41 may be a non- woven or spunbond thermoplastic (for example a polypropylene)non- woven material. The fifth layer 41 includes the resistive heating portion 30, and especially all the previously described components including the heating elements 34 which may be in the form of electrically conductive ink, bonded or coupled to the interior surface 42 of the fifth layer 41 facing the fourth layer 18.

A pair of double-sided tape strips 44 may be applied to the fifth layer 41 so that it may be attached or coupled to a pre-existing warming blanket. Also, if need be, the fifth layer 41 with the electronic components may be easily removed or released from the warming blanket. As such, an existing warming blanket may be converted from a static or strictly body heat capturing warming blanket to a positive or active electrically resistive heat added warming blanket. The warming blanket may then be reconfigured to a static body heat capturing warming blanket by removing the fifth layer 42 and electronic components. In this manner, the electronic components may be attached and then removed from multiple warming blankets should they become soiled or otherwise unusable and may be disposed. This disposability decreases the expense involved in providing warming blankets having resistive heating capabilities.

It is believed that this embodiment provides an even higher amount of heat dispersement or distribution as a portion of the heat from the heating elements 34 initially radiating in the direction away from the patient is dispersed as it passes through the fourth layer 18, is reflected by the second layer 16, and then disperses even more as it passes again through the fourth layer 18 prior to reaching the person, i.e., the heat passes through the fourth layer 18 twice before reaching the person. This also allows the temperature of the conductive heating element 34 to be set at a lower temperature because of the additional reflected heat being directed back to the person.

It should be understood that as used herein the term “lofted” is intended to mean something that is fluffed, fluffy, expanded, expanded layers, or the like. Also, the term “billow” or “billowed” is intended to mean raised, embossed, undulating surface, having lofted areas, or the like. The use of a lofted inner material is believed to allow the heat from the heating elements 34 and that reflected back from the metalized second layer 16 to spread or diffuse the heat so as to provide a more even heating, as opposed to a concentration of the heat should a thin layer be utilized.

With reference next to the embodiment of Figs. 7-13, there is shown a heating blanket 40 in another preferred form of the invention.

Here, the heating elements 34 are formed by adhering a small patch 53 of electrically insulative spunbond material to an exterior facing surface of an electrically conducrive veil material 52, wherein the electrically conductive veil material 52 may be a sheet, web, or mat at least a portion of which is randomly orientated electrically conductive fibers or sections of fibers, such as a carbon veil material carbon fibers or the like. The term carbon will be used hereinafter for ease of explaination in reference to the electrically conductive material, but it should not be construed to mean that this is a limitation of the present invention as many other electrically conductive materials or fibers may be used The carbon veil may be 20 to 25 percent carbon with the remaining portion a cellulose acetate for a carbon veil width of twelve inches. This provides an electric resistance of 3 to 7 ohms. If the carbon veil is wider the amount of carbon material therein should be increased to provide an even electric current distribution.

The carbon veil material 52 is then adhered, through sewing, adhesive, sonic welding or the like, to a second layer of electrically insulative spunbond material 63 which will be later bonded to a previously discussed metalized fabric 54. The metalized fabric 54 is generally the same as that previously described and which includes the first layer 15 of clear thermoplastic (for example a polyethylene) material, the second layer 16 of vaporized aluminum material (metalized layer), a third layer 17 of thermoplastic (for example a polyethylene) material, and a fourth layer 18 of lofted billow spunbond thermoplastic (for example a polypropylene) non- woven material. The third layer 17 and fourth layer 18 may also be electrically insulative.

Next, an electrode in the form of a conductive strip in the form of an electrically conductive ink layer 56, which may be made of metal or metal coated particles such as copper, nickel or silver ink, is deposited, sprayed upon, or printed onto opposite side edges of the carbon veil material 52. As such, the conductive ink layer 56 may also be termed as thin strips or side rails 56, also shown in Fig. 7. The conductive ink side rails 56 act to locally connect the random conductive fibers at different depth of the carbon veil material 52.

With reference next to Fig. 8, lower conductive strips 58 are then sewed on, or alternatively attached by electrically conductive adhesive or other bonding method, onto a bottom edge of the carbon veil material 52. Each lower conductive strip 58 is electrically coupled to a side rail 56. The lower conductive strips 58 may be made of an aluminum foil or other electrically conductive material. The lower conductive strips 58 are electrically insulated from the carbon veil material 52. The lower conductive strips 58 have connecting ends 60 which are spaced from each other so as to accept a connection circuit board described in more detail hereinafter.

With reference next to Fig. 9, side conductive strips 62 are then sewed onto the conductive ink side rails 56 in electrical contact with the conductive ink side rails 56. The nickel boundary of the conductive ink side rails 56 prevent resistance drift from occurring. The side conductive strips 62 are also sewn so as to be in electrical contact with the lower conductive strips 58.

The second layer of spunbond material 63 is then laminated or otherwise bonded (adhesive, sonic welding, or the like) about the periphery of the fourth layer (spunbond material) 18 and/or carbon veil material 52, thereby sandwiching the carbon veil material 52 between two layers of spunbond material. The second layer of spunbond material 63 protects the carbon veil material 52 while providing a soft exterior layer for patient comfort and safety. The combination of the second layer of spunbond material 63 with the first layer of spunbond material (metalized fabric) essentially creates an envelope surrounding or encasing the carbon veil.

With reference next to Fig. 10, a hole or opening 66 is cut into the metalized fabric 54 so as to expose the connecting ends 60 of the lower conductive strips 58. A backing plate 68 is then attached to the backside of the second layer of spunbond material 63 at the position of the opening 66, as shown in Fig. 11, or to a patch of spunbond material which is then adhered to the patient side of the blanket. The backing plate 68 may be passed through a slot or cut 67 in the second layer of spunbond material 63 so as to be placed flush against the patch 53, as shown in Fig. 13. The use of the backing plate 68 provides local support of the connection points of the warming blanket as well as providing pressure between the contact surfaces of the thermistor board and the lower conductive strips 58(cross rails). The backing plate 68 includes a set of mounting prongs 69 which extend through or are punched through the patent 53 and carbon veil material 52 so that they may engage, fit upon a snap-on circuit board 70 containing thermistors (thermistor plate 71), or thermocouples. The circuit board 70 is then mounted to the exterior surface of the metalized fabric 54 and connected to the connecting ends 60 of the lower conductive strips 58, as shown in Figs. 12 and 13. The circuit board 70 includes a large array of vias to assist heat transfer to the where the thermistors are located. The use of a large circuit board for connection purposes provides a more accurate average temperature of the heating fabric (carbon veil material), i.e., the temperature is sensed over a larger area for averaging purposes to minimize the possibility of errors. The vias transfer heat to the top side of the circuit board so that the thermistors can be captured within the connector housing. This also shields the thermistors for the safety of the operator.

In use, electric current is controlled through the circuit board 70 and passed to the connecting ends 60 of the lower conductive strips 58. The current then travels to the side conductive strips 62 and conductive ink side rails 56 where it is then passed to the carbon veil material 52 wherein resistive heat is created. The metalized fabric reflects the heat to produce an even distribution and more efficient use of the heat. The lofted material layers diffuse the heat to avoid a concentration of heat or hot spot. The circuit board 70 uses multiple thermistors to minimize variance. The placement of the thermistors on the circuit board 70 enables them to be on a re-useable portion of the warming blanket 50 rather than the disposable “blanket” or material covering portion. This placement reduces the replacement costs of the warming blanket.

It is believed that the sewing of the conductive foil of the lower conductive strips 58 and side conductive strips 62 to the second layer of spunbond material 63 and carbon veil material 52 provides a better electrical connection. It is also believed that the sewing maintains a better drapeability of the warming blanket. The improved drapeability is important for patient comfort, effective warming, and reduced cost of manufacture.

The sewing process of the lower conductive strips 58 and the side conductive strips 62 preferably is accomplished with the use of non-conductive cotton-poly blend threads.

With reference next to Fig. 14, there is a shown a portion of the carbon veil material 52. Here, the conductive ink side rails 56 are deposited upon the carbon veil material 52 so that the conductive ink penetrates into the interior or is embedded within the interior portion of the carbon veil material. Preferably, the conductive ink penetrates completely from one surface to the opposite surface, i.e, the conductive ink penetrates the entire thickness of the carbon veil, the “thickness” being the material size along the direction extending between the top surface and the bottom surface. The conductive ink may be as previously described, or may be a metal coated particle or flake such as copper ink, a silver coated carbon particle, a silver coated copper particle, or other similar material bound with a polymer. The polymer may be a latex or other suitable material.

In use, the conductive ink is applied or deposited upon the carbon veil in the following manner. The top surface of the carbon veil is masked to define a border or margin. A bottom foil side conductive strip 62' is then sewn to the side border of the carbon veil 52. A viscous electrically conductive ink to then deposited upon the margin or border area. Pressure is applied to the viscous conductive ink to force the conductive ink into carbon veil, specifically into the interstices between the fibers of the carbon veil. Thus, the conductive ink is saturated into the carbon veil so as to saturate or extend throughout the entire thickness, height or depth of the carbon veil, the depth being the thickness or depth in the vertical direction shown in Fig. 13 and often referred to as the Z- axis. A top foil side conductive strip 62” is then applied to the viscous conductive ink, which acts as an adhesive to bond the top foil side conductive strip 62” in place. A heat is then provided to cure the conductive ink.

It is believed that by having the conductive ink throughout the entire thickness of the carbon veil a better conductive connection is made by the conductive ink. As the carbon fibers of the carbon veil as short and separate from each other, there is a better dispersement of the electric current across the carbon veil as the interior carbon fibers now come into direct contact with the conductive ink and therefore better carry the electric current. This better dispersement of the electric current provides for an even heat and the avoidance of hot spots.

As an alternative to the sewing of the bottom foil side conductive strip, the conductive strip may be coupled to the carbon veil through sonic welding.

It should be understood that the description is for one method of constructing the warming blanket. The exact sequence of the steps involved in the construction may differ while still embodying the invention.

It should be understood that as used herein the term electrically conductive mat or web does not require the entire mat or web to be composed of electrically conductive fibers. For example, the electrically conductive mat or web may be made of 30% electrically conductive fibers and 70% of cellulose material. The composition will determine the resistance of the electrically condcutive mat, and therefore the heat produced by such.

It should be understood that sewing, adhesive bonding, sonic welding, heat welding, or any other conventional method of bonding or coupling, as used herein, are equivalent.

It thus is seen that a heating blanket using a metalized fabric and a method of manufacturing such is now provided which overcomes problems associated with heating blankets of the prior art. It should of course be understood that many modifications may be made to the specific preferred embodiment described herein, in addition to those specifically recited herein, without departure from the spirit and scope of the invention as set forth in the following claims.

Claims

1. A heating blanket comprising, a carbon veil material having a plurality of carbon fibers extending between a carbon veil first surface and a carbon veil second surface oppositely disposed from said carbon veil first surface; a first electrically conductive rail electrically coupled along a first side of said carbon veil, said first electrically conductive rail being an electrically conductive ink extending through said carbon veil from said first surface to said second surface; a second electrically conductive rail electrically coupled along a second side of said carbon veil material opposite said first side of said carbon veil material, said second electrically conductive rail being an electrically conductive ink extending through said carbon veil from said first surface to said second surface; a first electrically insulative layer overlaying a first surface of said carbon veil material; a second electrically insulative layer overlaying a second surface of said carbon veil material oppositely disposed from said first surface of said carbon veil material, and an electrical control circuit electrically coupled to said first electrically conductive rail and said second electrically conductive rail, whereby current passing from the electrical control circuit to the first and second electrically conductive rails passes through the carbon veil to create heat.

2. The heating blanket of claim 1 wherein said first electrically insulative layer includes heat reflective layer, a first thermoplastic layer overlaying a first surface of said heat reflective layer, and a second thermoplastic layer overlaying a second surface of said heat reflective layer oppositely disposed from said first surface of said heat reflective layer.

3. The heating blanket of claim 1 wherein said plurality of carbon fibers is a mat at least of a portion of which are randomly orientated carbon fibers.

4. The heating blanket of claim 2 wherein said first electrically insulative layer is a spunbond material.

5. The heating blanket of claim 4 wherein said second electrically insulative layer is a spunbond material.

6. The heating blanket of claim 1 wherein said first and second electrically conductive rails are made of an electrically conductive ink having a metal coated particles.

7. The heating blanket of claim 6 further comprising a first electrically conductive strip overlaying and in electrical contact with said first electrically conductive rail, and a second electrically conductive strip overlaying and in electrical contact with said second electrically conductive rail.

8. The heating blanket of claim 7 wherein said first and second electrically conductive strips are made of a metallic foil.

9. A heating blanket comprising, an exterior envelope of electrically non-conductive material; an interior layer of electrically conductive fiber material encased within said exterior envelope, said interior layer of electrically conductive fiber material having two oppositely disposed edge margins; a pair of spaced apart electrodes coupled to said electrically conductive fiber material at said twooppositely disposed edge margins, each said electrode of said pair of spaced apart electrodes being an electrically conductive ink saturating the depth of said edge margins of said electrically conductive fiber material, and an electrical control circuit electrically coupled to said pair of spaced apart electrodes, whereby current passes from the electrical control circuit to the electrodes and to the interior portion of the electrically conductive fiber material to create heat.

10. The heating blanket of claim 9 wherein at least a portion of said exterior envelope includes a heat reflective layer, a first thermoplastic layer overlaying a first surface of said heat reflective layer, and a second thermoplastic layer overlaying a second surface of said heat reflective layer oppositely disposed from said first surface of said heat reflective layer.

11. The heating blanket of claim 9 wherein said interior layer of electrically conductive fiber material is a material at least of a portion of which is randomly orientated carbon fibers.

12. The heating blanket of claim 9 wherein said exterior envelope is made of a thermoplastic, nonwoven material.

13. The heating blanket of claim 9 further comprising a first electrically conductive strip overlaying and in electrical contact with a first said electrode of said pair of spaced apart electrodes, and a second electrically conductive strip overlaying and in electrical contact with a second said electrode of said pair of spaced apart electrodes.

14. The heating blanket of claim 13 wherein said first and second electrically conductive strips are made of a metallic foil.

15. A heating blanket comprising, a electrically conductive veil material having a mat of electrically conductive fibers with a thickness extending between a top surface and a bottom surface; a first rail of electrically conductive ink deposited along and embedded within a first portion of said mat of fibers; a second rail of electrically conductive ink deposited along and embedded within a second portion of said mat of fibers oppositely disposed from said first rail of electrically conductive ink; a first covering layer overlaying a first surface of said electrically conductive veil material; a second covering layer overlaying a second surface of said electrically conductive veil material oppositely disposed from said first surface of said electrically conductive veil material, and an electrical control circuit electrically coupled to said first and second rails of electrically conductive ink, whereby current passing from the electrical control circuit to the first and second rails of electrically conductive ink passes through the electrically conductive veil to create heat.

16. The heating blanket of claim 15 wherein said first covering layer includes heat reflective layer and at least one thermoplastic layer overlaying said heat reflective layer.

17. The heating blanket of claim 15 wherein said electrically conductive veil material is a material at least of a portion of which is randomly orientated carbon fibers.

18. The heating blanket of claim 15 wherein said first and second electrodes penetrate the entire thickness of said mat of fibers.

19. The heating blanket of claim 15 further comprising a first electrically conductive strip overlaying and in electrical contact with said first rail of electrically conductive ink, and a second electrically conductive strip overlaying and in electrical contact with said second rail of electrically conductive ink.

20. The heating blanket of claim 19 wherein said first and second electrically conductive strips are made of a metallic foil.

21. A method of manufacturing a heating blanket comprising the steps of:

(A) providing a electrically conductive veil material;

(B) depositing an electrical conductive ink upon the electrically conductive veil material to form two electrically conductive rails;

( C) forcing the electrical conductive ink of the two electrically conductive rails into the interior of the electrically conductive veil material;

(D) coupling a first electrically insulative layer over a first surface of the electrically conductive veil material;

(E) coupling a second electrically insulative layer overlaying a second surface of the electrically conductive veil material oppositely disposed from the first surface of the electrically conductive veil material, and

(F) coupling an electrical control circuit to the first electrically conductive rail and the second electrically conductive rail.

22. The method of claim 21 wherein the first electrically insulative layer includes heat reflective layer, a first thermoplastic layer overlaying a first surface of the heat reflective layer, and a second thermoplastic layer overlaying a second surface of the heat reflective layer oppositely disposed from the first surface of said heat reflective layer.

23. The method of claim 21 wherein the electrically conductive veil material is a material at least of a portion of which is randomly orientated carbon fibers.