Patent Application
20170028669
This invention relates generally to insulation materials for use in athletic and other active garments, and more specifically to compressible, low-weight insulation materials with elastic memory that define variable or irregular surfaces for improved modulation of heat, moisture, and air exchange in use and at rest. The invention may also find application in medical support fabrics or dressings.
For those engaged in cold-weather activities such as mountaineering, ice climbing, skiing, snowboarding, alpine rescue, outdoor work, and the like, it is essential that gear be at once functional and feasible. For example, properly insulated garments and sleeping bags are necessary for safety and thermal comfort in challenging environments, but a balance must be struck between warmth and other factors, such as the weight, packability, and breathability/air permeability (i.e., transmission of air and moisture vapor) of the garment.
A garment that is excessively heavy or warm, or that has sub-optimal breathability, can result in lost energy and efficiency, thereby decreasing user performance, detracting from the enjoyment of the activity, and potentially increasing safety risks in high-consequence situations. Weight is a particularly important factor when designing insulation for active gear. Thus, insulated garments that strike an optimal balance between warmth provided and material weight are desirable.
The thermal insulation value of a given clothing material is often reported in “do” units. By way of illustration, one do unit allows a sedentary person at 1 met (the Metabolic Equivalent of Task, or the rate of energy produced per unit surface area of an average person at a given task) to remain indefinitely comfortable in an environment of approximately 70° F., 50% relative humidity and 0.01 m/s of air movement. Above that temperature, a person so dressed will be uncomfortably warm, and below that temperature, they will be uncomfortably cold. See, for example, The Engineering Toolbox, Clo—Clothing and Thermal Insulation (Jun. 30, 2015), http://www.engineeringtoolbox.com/clo-clothing-thermal-insulation-d_732.html; Saeed Moaveni, “Engineering Fundamentals: An Introduction to Engineering” Cengage Learning 377 (2015).
Accordingly, materials with higher do values attain and maintain thermal comfort for a user more efficiently than materials with lower do values. A relatively small amount of high-clo insulation may keep the wearer of a garment comfortable without adding undesirable weight to the garment, while a correspondingly high amount of low-clo insulation, with an attendant increase in garment weight, is needed to achieve the same level of comfort. Users of active gear prefer to focus their energy on performance and on enjoying the experience, rather than wearing, carrying, or otherwise transporting excess gear weight. Thus, providing garment insulation with improved do values is an important objective in designing active gear products.
Traditionally, down fill (e.g., goose down) has been valued for its warmth-to-weight ratio (i.e., down possesses a relatively high do value), which has generally been superior that of synthetic insulation materials. However, down fill suffers from a number of shortcomings, including migration (movement of down fill to a localized portion of an insulated chamber, resulting in uneven insulation and cold spots), protrusion of the down shaft through an interior or exterior garment layer, and a poor capacity to manage and/or transport moisture. Many users are familiar with down-filled garments becoming heavy, soggy, and cold when exposed to even moderate amounts of water. Such water exposure may come in the form of rain, wet snow, running water, ambient humidity, or perspiration that is generated during strenuous activities. When this occurs, the heat-trapping structures of the down plumes collapse, decreasing the do value and rendering the down effectively unfit for providing warmth. Excessive moisture can also substantially increase the weight of down, making down a poor, potentially life-threatening choice if conditions are uncertain or may become wet. Additionally, products featuring down fill typically require special care and costly reagents for cleaning. More recently, ethical concerns have arisen regarding some down-gathering practices.
Synthetic insulation materials provide an alternative to down fill. Such materials are typically constructed of polyester fibers that are molded into long, durable threads, or into short clusters that provide insulating loft. Synthetic insulation materials possess numerous advantages over down, including lower cost, improved water resistance, improved do value when wet, and quicker drying time. However, as mentioned, traditional synthetic insulation materials possess a low warmth-to-weight ratio when compared to down. Thus, more synthetic material is required to achieve thermal comfort, resulting in a heavier, bulkier garment. Therefore, alternative insulating concepts are needed.
Another concern for outdoor enthusiasts and those performing cold-weather tasks is how well a piece of gear “packs down” (e.g., “pack volume”) for efficient storage and transportation, both during and between activities. This is particularly important in the field, where a storage means (e.g., a backpack) is limited in size so that it may be comfortably worn or carried and used. As used herein, the term “compression profile” refers to the minimal amount of 3-D space an insulated product occupies when compressed by a user. Thus, the less space the insulated product can be made to occupy, the lower its compression profile.
By minimizing the compression profile of a given insulated item, a user is able to more easily transport additional items that may be necessary for a safe, enjoyable, and productive activity. While some down-filled garments may be packed to occupy a relatively small space, the aforementioned issues of down migration, protrusion of the down shaft through the garment exterior, and the slow drying time of wet down detract from the packability of down-filled garments. On the other hand, known synthetic garment insulations require more material to provide thermal comfort, resulting in decreased free air space and increased density. Such synthetic materials resist compression, resulting in subpar packability. Thus, insulating materials with improved (i.e., decreased) compression profiles for storage and transport are desirable.
Optimized management of moisture and airflow in a garment is another consideration for designers and users of active garments. As mentioned, strenuous activities such as ice climbing, ski touring, outdoor work, and the like can generate substantial body heat and increase humidity beneath an insulated garment. Excessive heat and humidity can be highly uncomfortable to the user and may result in further loss of fluids, heavier garments, and, often, intense cold when the user comes to a resting point in a cold environment. While strategic layering of wicking, insulating, and exterior materials is a common approach to this problem, wearing and changing multiple layers can be inefficient and cumbersome. Thus, materials are needed that efficiently manage inflow and outflow of heat, air, and moisture relative to the garment, while providing a desired degree of insulation. Preferably, such materials are also relatively lightweight and may be advantageously packed down for transport or storage.
Against this backdrop, the present invention has been created. In one aspect of the present invention, a compressible, low-weight insulating material includes an insulating material, wherein portions of the insulating material are removed or penetrated and cut (such as with a slit) so as to provide increased breathability and/or warmth-to-weight ratio and a decreased compression profile relative to the insulating material when fully intact. Portions of the insulating material may be removed, such that the insulating material provides the same or an increased amount of warmth with a lesser amount of insulating material present. Alternatively or in addition, portions of the insulating material may be penetrated or cut to create negative space or a passageway within the insulating material. Warm air may collect in the negative space, increasing the warmth conferred on the user by the same amount of insulating material. During activities, the cuts or slits may allow overly hot air and moisture to more easily escape.
In certain embodiments, the insulating material is an elastic material, such as a polyester fiber material, that defines an inner surface and an opposing outer surface. One or more portions of at least one of the inner and outer surfaces is removed or penetrated so as to increase heat transfer when the elastic insulating material is stretched and to decrease heat transfer when the elastic insulating material is at rest. In certain embodiments, the insulating material of the present invention may be formed of a single layer of an elastic insulating material. In other embodiments, the insulating material may include two or more layers formed of one or more elastic insulating materials. An outer water-resistant layer may be joined, for example, to an insulating material.
In various embodiments, polyester fibers of the elastic insulating material may be adapted for improved elasticity. For example, in certain embodiments, the polyester fibers may define one or more bends, kinks, swirls, coils, branches, and the like, such that a given fiber may overlap and/or engage with at least a portion of an adjacent fiber. When the elastic insulating material is stretched, the bends, kinks, swirls, or coils defined along a given fiber may partially or fully straighten while retaining elastic memory. When the elastic insulating material relaxes from a stretched state, the collective elastic memory of the engaged fibers facilitates a return to original length and configuration, including any bends, kinks, swirls, or coils. In certain embodiments, the elastic insulating material is a non-woven material. In other embodiments, the elastic insulating material is a knit material. In certain embodiments, the elastic insulating material includes a single material. In other embodiments, the elastic insulating material includes at least two different materials.
In some embodiments, one or more portions of the elastic insulating material is removed or penetrated to form perforations that run from an inner surface, through the elastic insulating material, to an opposing outer surface. In other embodiments, one or more recesses may be formed in at least one of an inner and an opposing outer surface of the elastic insulating material. In yet other embodiments, a slit is formed in at least one of an inner and an opposing outer surface of the elastic insulating material. It will be appreciated that a given material may include any one of, or at least two of, a perforation, a recess, or a slit, as well as other features described herein.
The perforations, recesses, or slits may assume the form of ovals, circles, crescents, scallops, mustaches, or other shapes, including polygons such as hexagons, rectangles, stars, squares, pentagons, heptagons, octagons, triangles, and the like. The perforations, recesses, or slits may be of consistent shapes or sizes or may be of varying shapes or sizes.
Due to the elastic nature of the insulating material and the shape or shapes of the various features defined therein, the perforations, recesses, or slits can widen when stretched and close when relaxed, thereby regulating heat transfer and ventilation in accordance with the movement of the elastic insulating material. The perforations, recesses, or slits are bounded and defined by walls of the interior elastic insulating material. Opposing walls of a given perforation, recess, or slit may be parallel to one another, substantially parallel to one another, or skewed or divergent with respect to one another.
For example, in certain embodiments, opposing walls of a given perforation are parallel to one another. In other embodiments, opposing walls may orient toward one another from an inner surface to an opposing outer surface of the elastic insulating material, thereby defining a perforation or a recess in the shape of a cone, a triangle, or a polyhedron such as, for example, a pyramid. A perforation, recess, or slit may travel either a linear path or a nonlinear or tortuous path through the elastic insulating material. It will be appreciated that a perforation, recess, or slit may define any number of shapes as it travels partially or completely through the elastic insulating material. For example, the perforation, recess, or slit may undulate, or spiral, or zigzag, or may form an hourglass shape as it travels through the elastic insulating material.
In certain embodiments, the perforation, recess, or slit is planar or substantially planar relative to the elastic insulating material (i.e., assuming the shortest path from the inner surface to the opposing outer surface). In other embodiments, the perforation, recess, or slit is nonplanar relative to the elastic insulating material (i.e., assuming a path through the elastic insulating material that is longer than the distance between the inner surface and the opposing outer surface).
A perforation, recess, or slit may be the same size, substantially the same size, or a different size at the inner surface of the elastic insulating material as at the outer surface of the elastic insulating material. For example, in certain embodiments, the interior walls forming the perforation, recess, or slit are parallel or substantially parallel to one another, resulting in a perforation, recess, or slit that is the same size, or substantially the same size, at the inner and outer surfaces of the elastic insulating material. For example, in various embodiments, the size of the perforation, recess, or slit at the outer surface may be from 75-100%, from 80-100%, from 85-100%, from 90-100%, from 95-100%, or from 99-100% the size of the perforation, recess, or slit at the inner surface. In other embodiments, the size of the perforation, recess, or slit a the outer surface may be less than 75% the size of the perforation, recess, or slit at the inner surface.
In another aspect of the present invention, an elastic insulating material defines an inner surface and an opposing outer surface. At least one of the inner surface and the opposing outer surface is adapted to decrease heat transfer across the elastic insulating material when stretched and to increase heat transfer across the elastic insulating material when relaxed.
In various embodiments, at least one of the inner surface and the outer surface is adapted to form a protrusion that expands away the given surface when the elastic insulating material is stretched. This increases the loft of the elastic insulating material, promoting retention of heat, moisture, and air. When the elastic insulating material is relaxed, the protrusion contracts toward the given surface, decreasing the loft of the elastic insulating material and promoting transfer of heat, moisture, and air. When used in a garment, the elastic insulating material of the present aspect may be disposed between a layer of an outer material and a layer of an inner material, the outer and inner layers serving to retain warm air trapped within the lofted insulation. In some embodiments, the outer material is a nonporous material.
In an embodiment, at least one of the inner surface or the outer surface defines a scallop-shaped slit with lobe elements. When the elastic insulating material is stretched, the lobes expand and protrude away from the given inner or outer surface, thereby increasing the loft of the elastic insulating material. When the elastic insulating material relaxes, the lobes contract towards the given inner or outer surface, thereby decreasing the loft of the elastic insulating material. Those of skill in the art will appreciate that recesses and protrusions of various other shapes and designs may be employed to variably increase or decrease the loft of the elastic insulating material without departing from the true scope and spirit of the invention.
It will be further understood that an insulating material of the present invention with recesses or slits defined along only one surface may be less elastic than (i.e., will not stretch as well as) an insulating material with recesses and slits defined along both of an inner surface and an opposing outer surface, or than an insulating material wherein perforations defined through the elastic insulating material from an inner surface to an opposing outer surface.
In various embodiments, the perforation, recess, slit, or protrusion may be formed by use of a laser as is known in the art. Use of a laser may confer the additional benefit of fusing together elastic insulating fibers that are in close proximity to the perforation, recess, slit, or protrusion. Being fused, the fibers may exhibit improved tensile strength and elastic memory, resulting in a more durable and responsive insulating material. The perforation, recess, slit, or protrusion may also be formed by use of a cutting die, such as a hot die, or another edged tool. A penetration may be made by, for example, a blade, a pin, a laser, a waterjet, or any other appropriate pointed tool for penetrating the elastic insulating material. Alternatively, the elastic insulating material may be manufactured using known techniques to define apertures, recesses, slits, scored lines, or protrusions, rather than being perforated, penetrated, scored, etched, or cut.
In another aspect of the present invention, a garment comprises a compressible, low-weight insulating material as disclosed herein. The compressible, low-weight insulating material may include one or more of the foregoing perforations, recesses, slits, scored lines, or protrusions. In some embodiments, the garment comprises an inner material layer, an outer material layer such as a shell layer, and layer of a compressible, low-weight insulating material. In other embodiments, the garment may comprise an outer layer, such as a waterproof outer fabric with a breathable liner, and a compressible, low-weight insulating material of the present invention. It will be appreciated that various constructions of a garment comprising a compressible, low-weight insulating layer of the present invention may be achieved without departing from the true scope and spirit of the invention.
The garment may be, for example, a jacket, a base layer garment, a pair of pants, a sock, a hat, a facemask or balaclava, a glove, a blanket, a sleeping bag, or the like. Panels of the compressible, low-weight insulating material may be placed in areas of the garment that correspond to those portions of a wearer's body that move, stretch, and/or generate heat during activities. Such areas may include, for example, the underarm and back areas of a jacket, the thigh area of a pant leg, the mouth and crown areas of a facemask or balaclava, the foot of a sock, and the foot box of a sleeping bag.
Multiple panels of a compressible, low-weight insulating material of the present invention may be placed at different locations along an insulating layer of a garment such that movement by a wearer of the garment creates a pumping or “billowing” effect. For example, perforated panels of the compressible, low-weight insulating material may be placed on along the outer or inner thigh of each leg of a ski pant. As a wearer of the ski pant performs skiing and walking activities, the various perforated insulating panels expand and contract to pump and circulate air and heat within and without the pant. Increased air circulation across the interior of the garment and from the interior of the garment to the outside environment may relieve or prevent undesirable buildup of heat and moisture.
Preferred and alternative examples of the present invention are described in detail below with reference to the following drawings:
The problem of striking a desirable balance between the weight, insulating properties, and compressibility of an insulating material may be solved by use of a compressible, low-weight insulating material of the present invention, wherein certain portions of an insulating material are removed so as to provide an increased warmth-to-weight ratio and a decreased compression profile relative to the insulating material when fully intact.
In certain embodiments, the insulating material is an elastic insulating material with portions thereof removed such that an insulating property of the elastic insulating material varies with stretching and relaxation of the elastic insulating material.
The insulating material 10b may form the construction of a garment such as a jacket. During physical activity such as clearing snow, rock climbing, or skiing, the motions of the wearer stretch and relax the insulating material 10b. As is further discussed with reference to
In other embodiments, the elastic insulating material is removed by scoring to create scored lines on at least one of the inner and outer surfaces. The scored lines define negative spaces or “valleys.”
The scored lines defined along each of the outer 12c and inner 13c surfaces are offset relative to the scored lines defined along the opposing surface. As the insulating material 10c is stretched in the direction of arrow C, the recesses or valleys defined by the scored lines widen, enlarging the negative space defined by the scored lines and permitting increased transfer of heat, moisture, and/or air. For example, the insulating material 10c will retain more heat at scored line 14c than at scored line 16c when the insulating material 10c is stretched in the direction of arrow C. In other embodiments, only one of an inner surface or an opposing outer surface, or a portion thereof, may be scored. A scored line may further define one or more perforations, and it may also define recesses of shapes other than those shown in
As can be seen in the side-elevational view at right of
The stretching and relaxing can also create somewhat of a pumping action of air and/or moisture through the insulating material. This pumping may aid in moisture transfer and cooling during times of high activity. As noted previously, the insulating material of the present embodiment may be disposed in an array of material forming the construction of a garment. For example, the insulating material may be disposed between an outer layer of a nonporous material and a layer of an inner material in a similar fashion to that depicted in
In another aspect of the present invention, a garment for use by a wearer comprises a compressible, low-weight insulating material. To facilitate stretching and relaxation of the insulating material, the insulating material may be formed or placed adjacent to a more stretch-resistant portion of the same material, such as a braided or quilted portion of the insulating material, or of a different stretch-resistant material.
In
Multiple panels of a compressible, low-weight insulating material of the present invention are placed at different locations along an insulating layer of a garment such that a pumping effect, like that of a bellows, is created by movement of the wearer. As the wearer of a jacket with insulating layer 40 pumps his or her left and right arms during an activity, perforated insulating material corresponding to the right underarm and ribcage region 46 and shoulder 47 and the left underarm and ribcage 44 and shoulder 45 of the jacket 40 expands and contracts to permit or improve airflow through the jacket. When movement of one arm is offset from movement of the other arm (e.g., during hand-over-hand climbing), widening and narrowing of perforations on opposing sides of the wearer's body can serve to pump air from one side of the body to another. Increased air circulation across the interior of the garment and from the interior of the garment to the outside environment may relieve or prevent undesirable buildup of heat and moisture.
At least the outer 52 and inner 56 layers are secured together by stitching, heat-sealing, taping, or other methods known to those of skill in the art to hold the insulating layer 54 in place and form the garment 50. The insulating layer 54 may also be secured to one or both of the outer 52 and inner 56 layers. It will be understood that any of the compressible, low-weight insulating materials described herein, including those depicted in
While the preferred embodiments of the invention have been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.
