Abstract:
A supplementary garment provides additional layering with a five-layer construction of clothing to supplement the functions of the outer two layers. The supplementary garment for layering includes a first supplementary garment worn directly inside an outer garment that is the outermost layer of the five-layer construction, so as to form a six-layer construction. The garment for layering can further include a second supplementary garment worn directly outside the outer garment so as to form a seven-layer construction.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a supplementary garment for additional layering with a five-layer construction of clothing. More particularly, the invention relates to a supplementary garment for layering used for activities in severe environments of extreme low temperatures such as alpine climbing, polar expedition operations and the like. 
         [0003]    2. Description of the Related Art 
         [0004]    Layering (wearing in layers) has been conventionally and commonly used in outdoor sports. Layered clothing having a three-layer construction is most commonly known for good mobility and suitable thickness/weight of the layer construction, and being sold by many outdoor clothing manufacturers. The three-layer construction includes, for example, a base layer closest to the skin, a mid layer or an intermediate garment (thick thermal wear with batting) and an outer shell that is the outermost layer (thick waterproof garment). Some users may wear two base layers or mid layers upon one another, or may further wear a vest or a jacket with a batting of down, synthetic fiber, or natural fiber, or made of a thick fabric such as pile fabric or raised fabric on the mid layer. However, a conventional three-layer construction (or four-layer construction) cannot satisfactorily maintain the wearer&#39;s mobility or the body temperature retention performance in an even severer environment, which may prove more serious particularly when the wearer is stranded in snow in mountains or in other situations where the wearer cannot move for a long period of time. Another problem with the three-layer construction is that when there is a large difference in temperature between outside and inside of the clothing, condensation of moisture inside the outer garment or sweat sometimes soaked through the thermal wear with the batting, thereby significantly lowering the heat retention performance. Once it is wet, the thermal wear with the batting does not dry up quickly, causing the wearer to feel colder. The present inventors therefore have proposed clothing with a five-layer construction. It is considered that condensation can be reduced significantly with five layers, as the layers form a sort of a double window structure inside. 
         [0005]    Meanwhile, a layering system of clothing for outdoor leisure activities such as fishing is known (JP-A-2002-30503). The document describes a system of layering including an inner layer, a mid layer, and an outer shell (vest or long-sleeved). 
       SUMMARY OF THE INVENTION 
       [0006]    However, there might possibly be a situation where even clothing with a five-layer construction is not enough under severe environments of extremely low temperatures such as polar regions or high mountains. It is assumed that five layers of clothing would not be sufficient in a low temperature environment of −10° C. or lower, or under conditions where the wearer loses his/her body temperature (body heat) quickly in a snowstorm or strong wind. Each of the layers forming the five-layer construction has a specific function. The outer two layers provide functions such as protection from or resistance to water, moisture permeability, heat retention, and condensation prevention, while the inner three layers provide durable water repellency, sweat wicking and evaporation, and heat retention. The outer two layers, in particular, are more likely needed to have their functions supplemented. On the other hand, layering of more than five layers of clothing will cause the problem of wearer&#39;s mobility to be restricted. The total weight and thickness of the layered clothing will increase, and the mobility will lower, in proportion to the number of layers. 
         [0007]    The present invention was made in view of the problems described above, and it is an object of the invention to provide a supplementary garment for additional layering with a five-layer construction of clothing to supplement functions of outer two layers of clothing without compromising the wearer&#39;s mobility. 
         [0008]    To solve the problems described above, the present invention provides a supplementary garment for additional layering with a five-layer construction of clothing, including a first supplementary garment worn directly inside an outer garment that is an outermost layer of the five-layer construction, or a second supplementary garment worn directly outside the outer garment instead of or in addition to the first supplementary garment, so as to form either a six- or seven-layer construction. Another aspect of the invention provides a supplementary garment including the first supplementary garment and the second. supplementary garment so as to provide a seven-layer construction. 
         [0009]    With this configuration, a supplementary garment is further added between the fourth layer and the fifth layer in the five-layer construction, so that heat retention performance can be reinforced without compromising the advantages of the clothing with the five-layer construction (for example, condensation prevention performance). The functions of the fourth-layer garment, for example, (such as resistance to water, heat retention, protection from wind, and condensation prevention) may be supplemented. 
         [0010]    Examples of the first supplementary garment include a construction with a batting of down, synthetic fiber, or natural fiber, a construction with air pockets (or an air layer) that can stay three dimensional under the pressure of layered clothing, or a thick fabric material such as pile fabric or raised fabric. With the present invention, soaking caused by condensation or sweat can be largely reduced even though the supplementary garment having excellent thermal properties is layered, so that the heat retention performance can be reinforced while the condensation prevention performance is maintained. 
         [0011]    By further layering a supplementary garment with the five-layer construction outside the fifth-layer garment, the fifth-layer garment can have its functions (such as protection from water, heat retention, and protection from wind) supplemented. Since this is equivalent to wearing two outer garments one upon another, the barrier function (protection from water) can be enhanced by the double outer layer, as well as the functions mentioned above (such as condensation prevention performance) can be improved. 
         [0012]    By layering the first supplementary garment and the second supplementary garment additionally with the five-layer construction, the heat retention performance can be further reinforced, as well as the barrier function (protection from water) can be enhanced, without compromising the advantages of the clothing with the five-layer construction (such as condensation prevention performance). 
         [0013]    In one embodiment of the invention, the first supplementary garment or second supplementary garment may be made of a stretchy fabric. Thereby a reduction in wearer&#39;s mobility can be effectively prevented. 
         [0014]    In the invention described above, the five-layer construction includes a first inner-layer garment on the skin, i.e. this inner-layer garment is underwear which is in contact with the skin, a second inner-layer garment worn on the first inner-layer garment, i.e. the second inner-layer garment is a second piece of garment placed in contact with the first inner-layer garment, a third inner-layer garment worn on the second inner-layer garment, a fourth inner-layer garment worn on the third inner-layer garment, and the outer garment worn on the first supplementary garment, i.e. the first supplementary garment is placed between the fourth inner-layer garment and the outer garment. 
         [0015]    In one embodiment of the invention, sweat on the skin is quickly passed through the first inner-layer garment (which is prevented from getting wet by sweat or rainwater from outside due to its durable water repellency), absorbed by and diffused in the second inner-layer garment, and evaporated by the wicking action of the third inner-layer garment. The evaporated sweat permeates through the fourth inner-layer garment, the first supplementary garment, and the outer garment (and the second supplementary garment) and is released to the outside. The first inner-layer garment directly contacting the skin may be made of a water repellent fabric, for example, while the second and third inner-layer garments that are worn thereon may be made of a fabric capable of retaining heat, wicking sweat away, and adjusting moisture. 
         [0016]    Another aspect of the invention is a layered clothing system including: a five-layer construction including a first inner-layer garment on the skin, a second inner-layer garment worn on the first inner-layer garment, a third inner-layer garment worn on the second inner-layer garment, a fourth inner-layer garment: worn on the third inner-layer garment, and an outer garment worn outside of the fourth inner-layer garment; characterized in that the layered clothing system further including; a first supplementary garment worn on the fourth inner-layer garment and directly inside the outer garment; or a second supplementary garment worn directly outside the outer garment instead of or in addition to the first supplementary garment, so as to forma six-layer construction. Another aspect of the invention is the layered clothing system, characterized in that the layered clothing system including the first supplementary and the second supplementary garment so as to a seven-layer construction. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a diagram for explaining a six-layer construction of Embodiment 1; 
           [0018]      FIG. 2  is a diagram for explaining a seven-layer construction of Embodiment 2; and 
           [0019]      FIG. 3  is a diagram for explaining a six-layer construction of Embodiment 3. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiment 1 
     6-Layer Construction 
       [0020]      FIG. 1  shows a six-layer construction. A first inner-layer garment  1  is worn directly on the skin. The first inner-layer garment  1  has water repellency to let the sweat pass through quickly and to prevent getting wet by sweat or moisture from outside. The first inner-layer garment  1  is made of a polyester fabric processed to have water repellency, for example. 
         [0021]    Reference symbol A in  FIG. 1  indicates the movement of sweat, i.e., sweat transferring from the first inner-layer garment  1  successively through all the garment to the outer garment  5  (direction of moisture permeability). Reference symbol B indicates moisture (sweat or rainwater) being prevented from soaking through (direction of waterproof performance). 
         [0022]    A second inner-layer garment  2  is worn on the first inner-layer garment  1 . The second inner-layer garment  2  provides heat retention, sweat wicking, and moisture adjustment to remove sweat from the first inner-layer garment  1  by absorption and diffusion. The second inner-layer garment  2  is made of a synthetic fiber such as polyester, natural fiber such as wool, silk, or cotton, or a fabric made of a mixture of these, for example. Reference symbol C in  FIG. 1  indicates sweat wicking and evaporation properties. 
         [0023]    A third inner-layer garment  3  is worn on the second inner-laver garment  2 . The third inner-layer garment  3  provides heat retention, as well as sweat wicking and evaporation, and vaporizes sweat. The third inner-layer garment  3  is made of a synthetic fiber such as polyester, natural fiber such as wool, silk, or cotton, or a fabric made of a mixture of these, for example. Reference symbol C in  FIG. 1  indicates sweat wicking and evaporation properties. 
         [0024]    A fourth inner-layer garment  4  is worn on the third inner-layer garment  3 . The fourth inner-layer garment  4  provides protection from wind, heat retention, and moisture-permeable waterproof, and transfers (passes) the evaporated sweat to the outside. The fourth inner-layer garment  4  has a three-layer structure of, for example, nylon (or polyester), a fluoride or polyurethane film, and nylon (or polyester). 
         [0025]    An outer garment  5  is worn on a first supplementary garment  10  to be described later. The outer garment  5  provides protection from cold and wind, moisture-permeable waterproof, and resistance to rain, and transfers (passes) the evaporated sweat to the outside. The outer garment  5  has a three-layer structure of, for example, stretchy nylon (or polyester), a fluoride or polyurethane film, and nylon (or polyester). The functions of the respective garments are not limited to those mentioned above. Some of the functions may be omitted, or other functions may be added in accordance with the purposes of use. 
         [0026]    The first supplementary garment  10  is worn on the fourth inner-layer garment  4  and under the outer garment  5 . The first supplementary garment  10  provides protection from wind, heat retention, and moisture-permeable, and has hydrophobic properties. Thereby, the first supplementary garment reinforces the heat retention performance without compromising the advantages of the five-layer construction (such as condensation prevention performance). The first supplementary garment  10  has, for example, a construction with a batting of down, synthetic fiber, or natural fiber, a construction with air pockets (or an air layer) that can stay three dimensional under the pressure of layered clothing, or a thick fabric material such as pile fabric or raised fabric. The first supplementary garment  10  should preferably have a light overall weight, so as to prevent a substantial reduction in wearer&#39;s mobility. 
       Embodiment 2 
     7-Layer Construction 
       [0027]      FIG. 2  shows a seven-layer construction. It is different from Embodiment 1 ( FIG. 1 ) in that a second supplementary garment  20  is further layered. 
         [0028]    The second supplementary garment  20  is worn on the outer garment  5 . The second supplementary garment  20  provides protection from cold and wind, moisture-permeable waterproof, and resistance to rain. It thus makes a double outer layer, which reinforces the barrier (waterproof) function, as well as reinforces the heat retention performance without compromising the condensation prevention performance. The second supplementary garment  20  may have a construction with batting, or a construction having an air layer such as pile fabric or raised fabric similar to the first supplementary garment, so as to further enhance the heat retention performance in an unanticipated, extremely low temperature condition. Alternatively, the second supplementary garment  20  may have a three-layer structure of, for example, nylon (or polyester), a fluoride or polyurethane film, and nylon (or polyester). The second supplementary garment  20  may have both of the three-layer structure and the construction with batting and/or construction with an air layer. Normally, the second supplementary garment  20  should preferably be light and stretchy so as to prevent a substantial reduction in wearer&#39;s mobility even when worn as one of seven layers. 
       Embodiment 3 
     6-Layer Construction 
       [0029]      FIG. 3  shows a six-layer construction of Embodiment 3. It is different from Embodiment 1 ( FIG. 1 ) in that the second supplementary garment  20  is layered instead of the first supplementary garment  10 . 
         [0030]    The second supplementary garment  20  is worn on the outer garment  5 . The second supplementary garment  20  provides protection from cold and wind, moisture-permeable waterproof, and resistance to rain. It thus makes a double outer layer, which reinforces the barrier (waterproof) function, as well as improves the condensation prevention performance. 
       Other Embodiments 
       [0031]    The respective garments described above are not limited to clothing for upper body and may be clothing for lower body. Examples of outer garments for lower body include thermal, windproof, and waterproof trousers, and examples of inner-layer garments for lower body include tights, leggings, half pants and the like. 
         [0032]    The thread materials or sewing techniques of the respective layers forming the garments are not limited to particular types. Various processing (for providing water repellency, UV protection, etc.) may be performed as required. 
         [0033]    To enable quick and effective adjustment of the body temperature, the third inner-layer garment  3 , fourth inner-layer garment  4 , outer garment  5 , first supplementary garment  10 , and second supplementary garment  20  may each have an opening that can be opened and closed to provide a ventilation function. The openings may be provided at positions in the respective garments corresponding in the thickness direction (cross-sectional direction) of the layers so that the openings in the lower layers and upper layers coincide with each other (are substantially at the same position) when the garments are worn. The respective openings may be provided in an underarm portion, for example.