TECHNICAL FIELD

(0002) The present invention relates to a light weight thermal insulating sheets comprised of a core formed of down material mixed with a heat activatable binder and plant based material fibers, in predetermined proportions, and wherein the plant based fibers provide resistant to core compression during heat setting of the binder and act as wicking conductors to improve the extraction of moisture from the down material in the core.

BACKGROUND OF THE INVENTION

(0003) Down material is a superior insulation that synthetic insulation for the fact that it traps warmth in thousands of tiny air pockets formed by the down clusters. At the same time is extremely breathable. Its ability to trap heat is measured by its fill power which measures how many cubic inches one ounce of down can fill. Down is well known to have a fill power of between 450 and 900. This means that one ounce of high quality down can fill 900 cubic inches. Down has a much higher warmth to weight ratio than synthetic insulation. In other words, although it provides more warmth, it remains very lightweight. This also makes it easier to compress down to take up far less pace in insulation products or for other reasons such as for transporting the product. Also, synthetic insulation does not come close when comparing to the resiliency of down. Down material can last for decades and still retain its loft and shape. However, while down posses all of these excellent characteristics, it has a few disadvantages

(0004) One disadvantage of down is that down material has its affinity to water and moisture and therefore has difficulty at repelling moisture and when it gets wet its insulating properties diminish. When used in articles of apparel, a lot of sweat is given off by a wearer person during exertion and this sweat is absorbed by the down material. This problem is addressed by the present invention which provides a means which constantly wick moisture out of the down material when present. It also provides for a quicker drying time after washing. (0005) Attempts have been made in the past to fabricate synthetic insulation to replace down and such has been commonly referred to as“synthetic down”. The use of microfibers mixed with crimped bulking fibers for use as an insulation in the fabrication of articles of apparel is known and described in US Patent 4,1 18,531 issued on October 3, 1978 to the Minnesota Mining and Manufacturing Company. As described

microfibers are heavier than alternative types of fibrous insulation. Since the surface area of microfibers is greater than polyester staple fibers, more air is held in place by the microfibers, which results in a deduced transfer of heat within a web containing microfibers. Although the percentage of microfibers in a web of this type of insulation is less than that of an all-microfiber web, sufficient microfibers are apparently retained to make the thermal resistance per unit of thickness of the web comparable to that of an all-microfiber web. Loft and resiliency of such a web is provided by a blend with crimped bulking fibers. The advantage of such insulation using microfibers is that the insulation is of less weight and bulk as compared with insulation using polyester staple fibers and is just as warm. Such synthetic down material did not prove to have the same fill power of down and its disadvantages are numerous, such has the thickness of the insulation as compared to down to provide an equivalent CLO count and

consequently its weight increase. Therefore, its application as an insulator as its limitations.

(0006) In my US Patent No. 6,025,041 , there is discussed the problems of using down as an insulation, particularly in the fabrication of articles of apparel. Down insulation from goose or duck is known to have excellent insulation properties due to their ability to retain heat. Because down is a natural product it is more expensive than synthetic fibers, such as polyester. It would therefore be desirable to use the qualities of both down and synthetic fibers to fabricate a thermally insulating material having excellent insulating properties and other features including reduce cost, faster drying time and more resistant to shrinkage and provide improved lofting as compared to down insulation. The present invention provides a down/polymer thermally insulation sheet which provides this reduction in cost while at the same time providing other benefits in overcoming manufacturing problems such as maintaining loft during the process of fusing the down and polymer fibers together. SUMMARY OF INVENTION

(0007) It is therefore a feature of the present invention to provide a light weight down/polymer insulating sheet having an improved core structure which provides high thermal efficiency, resiliency and lofting while at the same time overcoming known problems of down material.

(0008) Another feature of the present invention is to provide a down/polymer thermally insulating sheet comprised of down mixed binding fibers and plant-based material fibers to provide improved lofting, resiliency and drying time.

(0009) Another feature of the present invention is to provided a down/polymer thermally insulating sheet comprised of a core having a down core mixture which provides added benefit to the finished product at a reduced cost.

(0010) A still further feature of the present invention is to provide a down/polymer thermally insulating sheet and wherein the core and polymer fibers are mixed with plant- based material fibers wherein a core structure is formed during heating of the core in its fabrication whereby to resist to compression of the core material caused by the fusing of the fibers.

(001 1 ) A further feature of the present invention is to provide a light weight

down/polymer thermally insulating sheet comprised of a central core zone and outer trapping barrier zones capable of preventing the escapement of down clusters while also providing breathability and permeability to wick humidity from the central core zone.

(0012) Another feature of the present invention is to provide a central core zone comprised of down material, binding fibers and other materials providing mass and volume to the core and orientation support of plant-based material fibers to form a support fiber structure resisting to compression during heat treatment of the core to bind the material mixture.

(0013) Another feature of the present invention is to provide a light weight

down/polymer thermally insulating sheet and wherein the down/polymer core material and/or the outer scrim sheet comprise an odor absorbing substance or fibers containing carbon for absorbing odors emanating from a person’s body having at least a portion of its body covered by the thermally insulating sheet incorporated in article of warmth, such as an article of apparel, a sleeping bag, a duvet cover or other articles of warmth.

(0014) According to the above features, from a broad aspect, the present invention provides a light weight composite down/polymer thermally insulating sheet comprised of a core formed of down material mixed with a heat activatable binder material and plant- plant-based material fibers in predetermined proportions. The plant-based material fibers are dispersed and supported in a three-dimensional fiber structure by the down material. The plant based material fibers when subjected to heat treatment temperature to activate said binder material, maintaining their original state due to their melting temperature being higher than the heat treatment temperature causing the binder material to bind thereto and thereby creating an inner bonded support fiber structure made of the plant based material fibers in their original state and with at least some of the binder material attached thereto. The inner bonded support fiber structure maintains the loft in the core by resisting to heat deformation during the heat treatment of the binder material to reduce compression of the core by heat deformation of the binder material. The plant-based material fibers also act as wicking conductors to conduct moisture out of the down material and providing a faster drying of the thermally insulating sheet.

(0015) According to another broad aspect of the present invention there is provided . a light weight composite down/polymer thermally insulating sheet comprised of a central core zone formed of down material and opposed thermally insulating outer trapping barrier zones integrally bonded to a top and a bottom outer surface portions of the central core zone. The central core zone contains a binder material to trap the down material. The outer trapping barrier zones are comprised of a mixture of the binder material mixed with plant-based material fibers in predetermined proportions to form a higher density trapping zone to prevent loose down clusters from the central core zone to propagate to an outer top and bottom surface of the down/polymer thermally insulating sheet. The plant-based material fibers impart to the outer trapping barrier zones breathability and permeability to wick humidity from the central core zone to provide faster drying time while maintaining resiliency and stretchability of the thermally insulating sheet permitting it to drape well for use in the manufacture of thermally insulating articles.

(0016) According to a still further broad aspect of the present invention there is provided a light weight composite down/polymer thermally insulating sheet comprised of a core formed of down material mixed with a predetermined quantity of a heat activated binder material. The insulating sheet further contains an odor absorbing substance.

The odor absorbing substance is constituted by one of carbon fibers mixed with the down and the heat activated binder and a scrim sheet formed of charcoal yarn bonded to at least one of opposed top and bottom surfaces of the core, to absorb odors emanating from a wearer person’s body when the thermally insulating sheet is incorporated in an article of warmth.

DESCRIPTION OF THE DRAWINGS

(0017) A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which:

(0018) Figure 1 is a simplified illustration of a system for the fabrication of the insulating sheet of the present invention;

(0019) Figure 2 is a fragmented cross-sectional view of a polymer insulation sheet fabricated with down and polymer insulation and a binder;

(0020) Figure 3 is another fragmented cross-sectional view of a down insulation sheet fabricated with down and polymer fibers or natural fibers and a binder;

(0021 ) Figure 4 is a perspective view of a crimped bulking fiber;

(0022) Figure 5A is a fragmented cross-sectional view of a modified down/polymer core mixture incorporating therein plat based material fibers to overcome problems associated with down material in the core and the manufacturing process when heat setting the binder material of the core;

(0023) Figure 5B is a magnified view illustrating the heat set material fiber structure with fibers extending in a three-dimensional array; (0024) Figure 6 is a fragmented cross-sectional view of a down/polymer insulation sheet formed of a central core zone of down material and opposed thermally insulating outer cluster trapping and moisture wicking barrier zones;

(0025) Figure 7 is a fragmented cross-sectional view of one of the trapping barrier zones;

(0026) Figure 8 is a magnified fragmented view of the down/polymer insulation sheet material of Figure 6 and wherein additional volume forming material is shown added to the down, binder and plant-based material fibers to provide added loft and support of the fibers during heat setting to form a fiber support structure resisting to compression by the heat setting material during heat treatment,

(0027) Figure 9 is a microscopic view of an adhesive fiber web used as an outer scrim of the thermally insulating sheet material and which is heat set on outer surface of the material during heat setting of the core material, and

(0028) Figure 10 is a fragmented cross-sectional view of the down/polymer thermally insulating sheet and wherein the core contains a predetermined quantity of an odor absorbing substance containing carbon to absorb odors and wherein the scrim sheets may be formed entirely or partially with carbon or charcoal yearns to absorb odors.

DETAILED DESCRIPTION

(0029) Referring now to the drawings and more particularly to Figure 1 , there is shown generally at 10 a machine or system for the fabrication of the light weight insulating sheet 1 1 . As shown down insulation 12, in the form of goose or duck feather down or a mixture thereof, is injected or released through a chute 16 in an air mixing chamber 13 wherein air orifices 14 inject air under controlled pressure to cause a controlled turbulent mixing flow 15 in the mixing chamber. Added to the mixing chamber 15 through another chute 17, or otherwise injected are suitable polymer fibers, such as polyester fibers 18 or crimped bulking fibers 19, as illustrated in Figure 4. A binder in the form of a powder glue 20 or binding polyester fibers, which react to heat may also be released in the mixture, herein the turbulence flow 15. (0030) As shown in Figure 1 , a backing fabric sheet 22 is laid onto the top surface of the conveyor and moves with the conveyor. The conveyor belt 21 is driven by a driven drum 35. The deposited mixture is a thoroughly intermixed homogeneous mixture. The speed of the conveyor determines the thickness of the insulating sheet 1 1 . The mixed material leaving the mixing chamber 13 is then compressed by the compression belt assembly 23 and conveyed into a heat treatment chamber 24 where it is subjected to heat to either melt the powder glue to bind the down and fibers together or to soften the crimped bulking fibers or other polymeric fibers to bind together at their crossings to trap the down mixture. Accordingly, there is thus formed the insulating down and fiber mixed insulating sheet of the type shown in Figures 2 and 3.

(0031 ) Figure 2 illustrates a mixture of down feathers 12’ and suitable polymer fibers 18’ capable of binding together when subjected to heat and trapped between the backing support sheet 22 and an opposed top fabric sheet 25. The polymer fibers 18 may be crimped bulking polymer fibers 19 such as the fiber illustrated in Figure 4 which due to its form exhibits stretchability, as is well known in the art. Additionally, micro fibers 32 may be added to the mixture to improve bonding of more fibers while improving the loft by the use of ultra thin fibers resulting in additional air space. The bottom fabric sheet 22 and top fabric sheet 25 are fabricated from light weight material and preferably, but not exclusively, have stretchable properties to provide flexibility to the insulating sheet 1 1’.

(0032) As shown in Figure 3, the insulating sheet 1 1” is formed of a mixture of the down material 12’ mixed with suitable polymeric fibers or natural fibers 18’, such as wool, bamboo fibers, bean, charcoal, milk and other suitable fibers or compositions thereof having insulating and lofting properties. This mixture includes the glue powder particles 20 as above mentioned in admixture and when subjected to heat, the glue binds the mixture together. As with Figure 3 the thermally insulating light weight mixture may be held captive between opposed fabric sheets 25 and 22 which may be formed of stretchable polymer fibers.

(0033) The light weight thermally insulating sheet as described above in its example of mixture and fabrication has a multitude of uses and not limited to articles of apparel, and as examples only, it may be used in the manufacture of duvet covers, liners for winter boots, and any other article of commercial use where light weight insulating material in sheet form is desirable. It is also pointed out that the light weight insulating sheet thus produced has improved resiliency and lofting due to the use of polymer fibers as above described. The polymer fibers also provide for a faster drying time of the mixture with down as compared to a full-down insulting sheet and provides minimal shrinking.

(0034) As mentioned herein above there is a need to increase the efficiency of the use of down material in a thermally insulating fabric structure including the need to overcome a certain problem during the fabrication of the down sheet to maintain the loft of the down sheet.

(0035) During fabrication when the down and binder polyester fibers are subjected to heat, in the range of about 150degrees F to 170 degrees F, during heat setting of the composition wherein the fibers soften and interconnect at their crossings and also attach to down cluster, the fibers in the mixture soften and do not maintain their stiffness and tend to collapse in the mixture although held partly by the down material. Such collapsing causes the mixture to compress or loose some of its loft. In order to substantially reduce this compression or collapsing of the soften binding fibers I have discovered that by adding plant based material fibers to the mixture and which fibers can maintain their form during the heat treatment that such plant based fibers would offer resistance to the deforming binding fibers and that the melting material at the outer surfaces of the binding fibers would attach to the plant based fibers creating a fibers structure, much like the framework of a building, supporting the mixture and resisting to compression of the core material. In addition to resolving this compression problem, the plant base material fibers, I have found, also act as wicking conductors for moisture absorbed by the down in the core material and therefore resolve another problem associated with down material thermal insulation. Such plant based material fibers also further provide added features and benefits when used with down material, namely that when the down is wet it dries very quickly to maintain its shape, it provide softness, it stretches and recover quickly, it is resilient and offer breathability, it is light weight and wrinkle resistant as well as being UV and chlorine resistant and biodegradable, all of which features compliment its use with down material. Such additive material also does not affect the draping of the insulation sheet when used in articles of warmth

(0036) Figures 5A and 5B illustrates a first embodiment of the improvement of my down/polymer thermally insulating sheet wherein, as shown, the down/polymer sheet 40 is herein comprised of down material 41 mixed with binding fibers 42 and plant-based material fibers 43. Glue particles 44 may also be added to the mixture to provide additional binding of the composition. An air permeable, non-woven, scrim sheet 45 may also be heat bonded to the outer top and bottom surfaces of the sheet as described herein above.

(0037) I have found that the use of plant-based material fibers identified by the registered trademark SORONA of the DuPont company which is a polyester microfiber made partially of corn glucose provides the results sought to provide the improvement of my new composition mixture. When added to the mixture, it produced the benefits sought after, namely the support fiber structure to resist to heat compression of the mixture and its wicking feature to extract moisture from the down material. Another plant-based material providing similar features is a cellulosic yarn fiber made from esters of wood pulp, such as that identified by the registered trademark NAIA of the Eastman company. These fibers have a melting temperature above 200 degrees F, namely in the range of 200 degrees F to 240 degrees F wherein during heat setting of the binder material in the range of 150 degrees F to 170 degrees F, the plant based material fibers maintain their original shape and with the binder material clinging thereto thereby creating a three dimensional framework or fiber structure resisting to

compression of the down by the melting binder material deformation causing a compression force on the fluffy and soft down clusters.

(0038) Because of the sought after features that plant-based material fibers can provide, a further embodiment of the down/polymer insulating sheet, as shown in Figures 7 to 8 was conceived. This light weight composite down/polymer thermally insulating sheet 50 is herein comprised of a central core zone 51 formed of down material 52 and opposed thermally insulating outer trapping barrier zones 53 integrally bonded to a top and a bottom outer surface portions of said central core zone 51 . The central core zone 51 contains a binder material, herein polyester binding fibers 54 to trap the down material 52. The outer trapping barrier zones 53 are formed by a mixture of the binder fibers 54 mixed with plant-based material fibers 55 in predetermined proportions to form a higher density trapping zone to prevent loose down clusters from the central core zone 51 to propagate to an outer top and bottom surface of said down/polymer thermally insulating sheet 50.

(0039) As shown in figure 7, the fiber mixture in the outer fiber trapping zones 53 extend in a substantially horizontal plane for the reason that there are no down material giving it loft and the fibers are distributed in random directions which causes them to bind to one another at their many crossings. There may be as much as 50% plant - based fibers to binding fibers in the outer fiber trapping zone mixture sufficient to prevent down clusters 56 from escaping from the insulating sheet 50 and to sufficiently wick out humidity from the core. These plant-based material fibers therefore impart to the outer trapping barrier zones breathability and permeability to wick humidity from said central core zone and provide faster drying time while maintaining resiliency and stretchability of the thermally insulating sheet permitting it to drape well for use in the manufacture of thermally insulating articles.

(0040) In order to provide a central core with improved loft and breathability and faster drying time, the central core zone a predetermined quantity of plant-based material fibers 55 are added to the mixture and they constitute internal wicking fibers distributed throughout the core zone. They provide the benefits as described above with respect to Figures 5A and 5B. Accordingly, the entire sheet structure includes wicking plant-based material fibers.

(0041 ) The thickness ratios between said central core zone 51 and the outer trapping barrier zones 53 are one of approximately 70% to 90% central core zone 51 and 5% to 15% for each said outer trapping barrier zones 53. The outer trapping barrier zones 53 have a thickness ratio in the range of 5% to 10% of the total thickness of said thermally insulating sheet 50. (0042) As shown in Figure 8, in order to improve loft of the central core zone 51 , there may be added to the mixture one or a combination of crimped bulking fibers 57, hollow fibers 58, natural fibers 59 and microspheres 60. Such microspheres 60 are dispersed in the mixture in predetermined quantities depending on their expansion characteristics and become trapped in said central core zone by the outer trapping barrier zones 53. They are also held dispersed in the mixture of the central core by the binding fibers or other materials of the mixture. These microspheres expand when subjected to the fusing heat treatment to produce loft in said central core zone to counter the above mentioned compression formed by said melting binding fibers and thereby maintain the desired loft of said central core zone 51 after the heat treatment.

(0043) As also shown in Figure 8 a scrim sheet 61 may be fused on opposed top and bottom surfaces of the thermally insulating sheet 40 or 50. As shown in Figure 9, the scrim sheet may be comprised of a meltable thin fiber mesh 63 formed by a high density mixture of polyester fibers that become impregnated in the top and outer surface of the insulating sheet during heat treatment to fuse the core material. Once impregnated the mesh is practically invisible but is air permeable to permit the evacuation of moisture while preventing the escapement of down clusters. The scrim sheet may also be comprised, although not shown, of a non-woven spunbound fabric sheet as available and described at the website“ www.acmemiiis.com/brands/non-woven-spunbound fabric”. Such a sheet can be heat bonded to opposed outer surfaces of the thermally insulating sheet of the present invention. Spunbound fabrics are formed by filament fibers comprised of one of nylon, polyester, and blends to provide excellent thermal properties, superior moldability, added strength, high dimensional stability, inherent UV stability and good permeability. The outer non-woven spunbound fabric sheets would be bonded by a thermally activated binder material.

(0044) Fleat activated binding fibers, as referred to herein, are fibers that form an adhesion or bond with other fibers at predetermined temperatures. These can include fibers having a polyester core and sheath fiber with a predetermined melt temperature. Bulking fibers are fibers that provide volume such as high denier per filament, high crimp fibers, hollow-fill fibers and other such type. Examples include polyester, polypropylene and cotton as well as other low cost fibers

(0045) Referring to Figure 10 there is shown another embodiment of the

down/polymer thermally insulating sheet 70 herein shown as comprised of a core 71 comprised of down cluster material 72 and binder material comprised of binding fibers 73, as previously described and optionally glue particles 74 mixed with the binding fibers 73 in predetermined quantity. A scrim sheet 75 also optionally may be bonded to one or both of the upper and lower surface of the core material.

(0046) The improvement herein illustrated is the incorporation into the core material of a predetermined quantity of odor absorbing substance in the form of carbon fibers 76 which absorbs odors. The predetermined quantity of carbon fibers would depend on the intended use of the insulating sheet 70. For example, more carbon fibers would be incorporated into the core 71 if the use of the insulating sheet is to be incorporated into articles of warmth used for sports activities where the wearer person would generate more sweat and consequently more body odors. For leisure articles of apparel less amount of carbon fibers would be necessary.

(0047) If scrim sheets 75 are bonded to one or the upper or lower surfaces of the core 71 , the scrim sheet may be formed as woven fabric sheets woven with charcoal yarn or other absorbing material yarns to absorb odors emanating from a wearer person’s body. The scrim sheets may also be formed of non-woven material impregnated with carbon fibers. It is pointed out that such odor absorbing feature of the down/polymer thermally insulating sheet can be used in other sorts of articles of warmth, such as sleeping bags, duvet covers, pants or other articles intended to be incorporated into articles of warmth to be positioned against a user person.

(0048) The down material clusters also have some fat trapped in their clusters having been attached to the skin of the bird and that fat can generate a smelly odor. Flowever, it is important to keep this oily fat in the down clusters to maintain their integrity and a longer effective lasting time. It is also pointed out that the odor absorbing substance may optionally include an odor eliminating compound such as activated silica essential oils, vinegar, bamboo charcoal-doped cotton, or charcoal-doped cotton, polyester, silk or other carbonaceous absorbent materials combination thereof.

(0049) It is therefore within the ambit of the present invention to cover any obvious modification of the examples of the preferred embodiment described herein, provided such modifications fall within the scope of the appended claims.