Abstract:
The invention relates to a knitted bra ( 10 ), comprising at least a first knitted cup ( 12   a ) and a second knitted cup ( 12   b ) which are transversely aligned and each have an overall hemispheric shape, each cup ( 12   a   , 12   b ) comprising a first elastically extensible knitted peripheral portion for supporting the chest, a stiffener ( 20 ) portion which extends at least partially under each cup ( 12   a,    12   b ), and a strap ( 14 ) for attaching the back of the bra ( 10 ), characterised in that the stiffener ( 20 ) forms an underwiring strip which at least partially surrounds the first peripheral supporting portion ( 30   a,    30   b ) of each cup ( 12   a,    12   b ), and in that the stiffener ( 20 ) is knitted in a first type of stitch designed for replacing an added underwiring.

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to a brassiere which is made of circular knit-fabric and which includes a plurality of portions having variable elasticity. 
       BACKGROUND 
       [0002]    It is known to make a knit-fabric brassiere, in particular circular or tubular knit-fabric brassiere, such as the brassiere described and shown in the document U.S. Pat. No. 4,531,525. 
         [0003]    This brassiere type, which is made by means of a circular knitting machine provided for this end, has the advantage of being comfortable to wear and of offering some flexibility and elastic extensibility. 
         [0004]    A brassiere described and shown in the document U.S. Pat. No. 7,163,432, which aims in particular to propose a brassiere adjustable to different sizes, is also known. 
         [0005]    According to this document, the brassiere includes a first knitted cup and a second knitted cup which are transversely aligned and each have a generally hemispherical shape. 
         [0006]    Conventionally, the brassiere includes a strip for attaching the back and a pair of straps. 
         [0007]    Each cup includes a first lower peripheral portion which is made of knit-fabric, for supporting the chest. 
         [0008]    Complementarily, each cup is supported by a lower tubular added underwire forming a stiffener, which is sewn or glued under each cup. 
         [0009]    Although this type of brassiere offers some elasticity, allowing to adapt to different sizes, the added underwire risks to cause discomfort to the person wearing the brassiere. 
         [0010]    In addition, the underwire attachment on the brassiere requires an additional manufacturing operation. 
       BRIEF SUMMARY 
       [0011]    To overcome these drawbacks in particular, the invention proposes a brassiere made of knit-fabric, of the type including at least: 
         [0012]    a first knitted cup and a second knitted cup which are transversely aligned and which have each a generally hemispherical shape, each cup including a first elastically extensible peripheral portion which is made of knit-fabric, for supporting the chest, 
         [0013]    a part forming a stiffener which extends at least partially under each cup, and 
         [0014]    a strip for attaching the back of the brassiere, 
         [0015]    characterized in that the stiffener forms an underwire strip which surrounds at least partially the first peripheral supporting portion of each cup, and in that the stiffener is made of knit-fabric according to a first type of stitch designed to replace an added underwire. 
         [0016]    Thus, the invention allows to provide a brassiere allowing an optimal chest holding without the need to resort to added underwires nor to thermoformed cups. 
         [0017]    According to another characteristic, the stiffener has a low or null elastic extensibility according to a vertical direction, perpendicular to a transverse direction, so as to support the chest. 
         [0018]    In addition, the first peripheral supporting portion of each cup has a vertical elastic extensibility superior to that of the stiffener, and in that said first portion is vertically responsive, so as to lift the chest without crushing it. 
         [0019]    Also, each cup includes a second inner annular portion which is adjacent to the first portion, which is transversely and vertically elastically extensible, and which has a vertical and transverse elastic extensibility superior or equal to that of the first portion. 
         [0020]    The second portion allows in particular to give depth to the cups when the brassiere is worn. 
         [0021]    According to another aspect, the stiffener and the first portion of each cup includes a number of stitches per unit area which is inferior to the number of stitches per unit area of the second portion of each cup, to make the stiffener and said first portion less transversely extensible than the second portion. 
         [0022]    In addition, each cup includes a third central portion which is adjacent to the second portion, which has a generally circular shape arranged generally at the center of the associated cup, and which has a vertical and transverse elastic extensibility inferior to that of the nearby second portion. 
         [0023]    Similarly, the third portion includes a number of stitches per unit area which is inferior to the number of stitches per unit area of the second portion of each cup, to make the third portion less transversely extensible than the second portion. 
         [0024]    Also, each portion of each cup is made of knit-fabric according to a different stitch type. 
         [0025]    In addition, the stiffener forms a central strip which connects the first cup and the second cup together so as to limit their transverse spacing. 
         [0026]    Finally, the different portions of each cup, the stiffener and the strip for attaching the back are made in one piece by circular knitting. 
         [0027]    This characteristic allows to make a large part of the brassiere according to the invention on a circular knitting machine in one single knitting step. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    Other characteristics and advantages of the invention will become apparent upon reading the detailed description which follows for the understanding of which reference will be made to the appended drawings in which: 
           [0029]      FIG. 1  is a perspective view, which illustrates a brassiere made of knit-fabric including a plurality of portions having variable elasticity, according to the invention; 
           [0030]      FIG. 2  is a plan view, which illustrates the brassiere of  FIG. 1 ; 
           [0031]      FIG. 3  is a schematic front view, which illustrates a first stitch type forming a stiffener; 
           [0032]      FIG. 4  is a schematic front view similar to  FIG. 3 , which illustrates a second stitch type forming a first portion of each cup; 
           [0033]      FIG. 5  is a schematic front view similar to  FIG. 3 , which illustrates a third stitch type forming a second portion of each cup; 
           [0034]      FIG. 6  is a schematic front view similar to  FIG. 3 , which illustrates a fourth stitch type forming a third portion each cup. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]    To clarify the description and the claims, the longitudinal, vertical and transverse terminology will be adopted without limitation, with reference to trihedral L, V, T indicated in the figures. 
         [0036]    Is shown in  FIG. 1  a brassiere  10  made of knit-fabric which is shown in a configuration worn by a standing person, so that the transverse direction T shown by the trihedral L, V, T in  FIG. 1  corresponds to a horizontal direction. 
         [0037]    The brassiere  10  includes a first knitted cup  12   a  and a second knitted cup  12   b  which are transversely aligned and which have each a generally hemispherical shape, of a convexity oriented forward according to a longitudinal direction. 
         [0038]    In addition, the brassiere  10  includes a strip  14  for attaching the back which is here composed of a first section  16   a  and of a second section  16   b  which are joinable together in the back of the user by a removable fastening means  17 , shown in  FIG. 2 . 
         [0039]    The fastening means  17  is of the clip and of the complementary notches type, for example. 
         [0040]    However, without limitation, the brassiere  10  can also be designed to be fastened from the front, between the two cups  12   a,    12   b,  according to a not shown design example. 
         [0041]    Similarly, the brassiere  10  can be made of tube without fastening means, to be slipped through the head. 
         [0042]    The strip  14  for attaching the back is made of knit-fabric extensible according to a transverse direction corresponding to its large length. 
         [0043]    Moreover, the brassiere  10  is equipped with a pair of straps  18   a,    18   b  which are designed to support the brassiere  10  on the shoulders of the user. 
         [0044]    As it can be seen in  FIGS. 1 and 2 , the brassiere  10  includes a knit-fabric part  20  which is called “stiffener”  20  in the following of the description. 
         [0045]    The stiffener  20  forms in particular an underwire strip  22  which extends under each cup  12   a,    12   b  to promote the support and the holding of each cup  12   a,    12   b.    
         [0046]    To this end, the underwire strip  22  of the stiffener  20  surrounds the lower periphery of each cup  12   a,    12   b,  generally the lower half of each cup  12   a,    12   b.    
         [0047]    In addition, the stiffener  20  forms a central strip  24  which connects the first cup  12   a  and the second cup  12   b  together so as to limit their transverse spacing relative to each other. 
         [0048]    Also, the stiffener  20  forms a first side strip  26   a  which connects the first cup  12   a  on the first section  16   a,  and a second side strip  26   b  which connects the second cup  12   b  on the second section  16   b  of the attaching strip  14 . 
         [0049]    The stiffener  20  is made of knit-fabric according to a first stitch type  28  illustrated in  FIG. 3  and described later, which is designed to replace an added underwire, such as a metal underwire, for example. 
         [0050]    For this purpose, the first stitch type  28  of the stiffener  20  has a low or even null elastic extensibility, according to a vertical direction. 
         [0051]    Here, “low elastic extensibility” means an extensibility which is inferior or equal to twenty percent, and preferably inferior or equal to ten percent relative to a rest state of the knit-fabric. 
         [0052]    According to another aspect, each cup  12   a,    12   b  includes, from the periphery toward the center of the cup, a first portion  30   a,    30   b,  a second portion  32   a,    32   b,  and a third portion  34   a,    34   b  respectively. 
         [0053]    The first portion  30   a,    30   b  forms the lower periphery of each cup  12   a,    12   b,  so as to support the chest. 
         [0054]    As it can be seen in  FIG. 1 , the first portion  30   a,    30   b  of each cup  12   a,    12   b  surrounds substantially three quarters of each cup  12   a,    12   b,  including a lower half and an upper outer side quarter, at the side of the arm of the user. 
         [0055]    In addition, the first portion  30   a,    30   b  of each cup  12   a,    12   b  is elastically extensible and it is made of knit-fabric according to a second stitch type  36  which will be described afterward. 
         [0056]    Moreover, the first portion  30   a,    30   b  of each cup  12   a,    12   b  has a vertical elastic extensibility superior to that of the stiffener  20 . 
         [0057]    Similarly, the first portion  30   a,    30   b  of each cup  12   a,    12   b  is sufficiently vertically responsive to lift the chest without crushing it. 
         [0058]    The term “responsive” translates here a capacity to exert a vertically important restoring force when the knit-fabric is taut. 
         [0059]    Complementarily, the second portion  32   a,    32   b  of each cup  12   a,    12   b  forms a ring which is arranged inside the first portion  30   a,    30   b.    
         [0060]    In addition, the second portion  32   a,    32   b  is elastically extensible according to a transverse direction and it has an elastic extensibility superior to that of the first portion  30   a,    30   b,  so as to obtain a satisfactory depth of the cups  12   a,    12   b.    
         [0061]    To this end the second portion  32   a,    32   b  is made of knit-fabric according a third stitch type  38  which is described afterward. 
         [0062]    Finally, the third portion  34   a,    34   b  of each cup  12   a,    12   b  forms a circle which is arranged at the center of the associated cup and which is surrounded by the second adjacent portion  32   a,    32   b.    
         [0063]    In addition, the third portion  34   a,    34   b  is elastically extensible and it has an elastic extensibility inferior to that of the second portion  32   a,    32   b.    
         [0064]    To this end, the third portion  34   a,    34   b  is made of knit-fabric according to a fourth stitch type  40  described afterward. 
         [0065]    The different portions  30   a,    30   b,    32   a,    32   b,    34   a,    34   b  of each cup  12   a,    12   b,  the stiffener  20  and the strip  14  for attaching the back are made in one piece by circular knitting. 
         [0066]    In addition, the different portions  30   a,    30   b,    32   a,    32   b,    34   a,    34   b  of each cup  12   a,    12   b  are arranged in a generally concentric way, as it can be seen in  FIGS. 1 and 2 . 
         [0067]    In  FIGS. 3 to 6  the visual rendering of a unit area  42  of the first stitch type  28 , of the second stitch type  36 , of the third stitch type  38  and of the fourth stitch type  40  respectively, is schematically shown, each unit area  42  being constituted of eight transverse rows of yarns forming eight vertical columns of knit-fabric. 
         [0068]    The eight yarn rows of each knit-fabric stitch type are successively constituted of a covered yarn F 1 , a first polypropylene yarn F 2 , a first textured yarn F 3 , a second polypropylene yarn F 4 , flat yarn F 5 , a third polypropylene yarn F 6 , a second textured yarn F 7  and a fourth polypropylene yarn F 8 . 
         [0069]    It is meant by “covered yarn” a yarn constituted of a central part called core, and of a peripheral part called coverage. 
         [0070]    The central part is an elastane or natural rubber yarn, for example, which gives the covered yarn elastic characteristics. 
         [0071]    The peripheral part is made of natural fibers, such as cotton or wool, or is made of synthetic fibers, such as polyamide or polyester, for example. 
         [0072]    However, according to the example described here, the covered yarn F 1  includes an elastane central part and a polyamide peripheral part. 
         [0073]    It is meant by “textured yarn” a flexible and voluminous yarn having elastic extensibility properties, unlike a flat yarn. 
         [0074]    The textured yarn is for example obtained by twisting smooth fibers, usually synthetic, to increase the volume thereof, making it soft to touch and a bit extensible. 
         [0075]    It is meant by “flat yarn” a yarn that does not stretch out, which is here made of polyester or of polyamide. 
         [0076]    The flat yarn is a mono-filament yarn, as opposed to a textured yarn which is a multi-filaments. The flat yarn is obtained by spinning the material to a sufficient speed, usually comprised between 1000 meters per minute and 5000 meters per minute, and if necessary by means of a complementary stretching to obtain an amorphous yarn or having a low degree of crystallinity, usually less than 5 percent. 
         [0077]    The extensibility of each stitch type  28 ,  36 ,  38 ,  40 , in a transverse direction in the sense of the yarn, and in a vertical direction in the sense of the stitch, is determined by the nature of the used yarn and the made knit-fabric type. 
         [0078]    Indeed, the stitches skipping technique, which comprises “keeping” a stitch on several rows, allows to vary the vertical extensibility of the knit-fabric. 
         [0079]    The stitch skipping is illustrated in  FIGS. 3 to 6 , by the loops which extend vertically on a plurality of rows afterward. The more extended the stitch skipping is, the lower the intrinsic vertical elastic extensibility of the knit-fabric is. 
         [0080]    As it can be seen in  FIGS. 3 and 4 , the first stitch type  28  and the second stitch type  36  include each a “kept” stitch on eight rows, alternating one column in every two. 
         [0081]    The yarn of the kept stitch of the first stitch type  28  is the flat yarn F 5 , which does not stretch out, so that the first stitch type  28  has low or even null vertical elastic extensibility. 
         [0082]    According to  FIG. 4 , the yarn of the “kept” stitch of the second stitch type  36  is the covered yarn F 1 , which is relatively elastic, so that the second stitch type  36  is too responsive vertically. 
         [0083]    For indication, according to an exemplary embodiment, the second stitch type  36  has a vertical extensibility of one hundred and forty percent relative to a rest state. 
         [0084]    As it can be seen in  FIG. 5 , which illustrates the third stitch type  38 , the first covered yarn F 1 , and the third textured yarn F 3 , the flat yarn F 5  and the textured yarn F 7  are each “kept” on two rows, one column in every four, forming stitches skippings arranged in staggered rows. 
         [0085]    Similarly, according to  FIG. 6  which illustrates the fourth stitch type  40 , the first covered yarn F 1 , the third textured yarn F 3 , the flat yarn F 5  and the textured yarn F 7  are each kept on two rows, one column in every two, forming stitches skippings arranged in staggered rows. 
         [0086]    Complementarily, the extensibility of each stitch type  28 ,  36 ,  38 ,  40 , in a transverse direction, in the sense of the yarn, is determined by the number of stitches per unit area  42 . The greater the number of stitches is, the higher the transverse elastic extensibility of the stitch tends to be. 
         [0087]    Referring to  FIGS. 3 to 6 , the first stitch type  28  and the second stitch type  36  include each thirty six stitches per unit area  42 , the third stitch type  38  includes fifty six stitches per unit area  42  and the fourth stitch type  40  includes forty eight stitches per unit area  42 . 
         [0088]    The high number of stitches of the fourth stitch type  40  allows to make the third central portion  34   a,    34   b  of each cup  12   a,    12   b  opaque, thus hiding the chest. 
         [0089]    The vertical elastic extensibility characteristics relating to different stitch types  28 ,  36 ,  38 ,  40  are described afterward. 
         [0090]    The first stitch type  28  has the lowest vertical extensibility, which is for example comprised between zero and twenty percent, and which is preferably equal to ten percent, or even zero percent, relative to a rest state. 
         [0091]    The second stitch type  36  has a vertical extensibility which is superior to that of the first stitch type  28 , and which is for example equal to one hundred and forty percent of stretching relative to a rest state. 
         [0092]    The third stitch type  38  has a vertical extensibility which is superior to that of the second stitch type  36 , and which is for example equal to one hundred seventy five percent of stretching relative to a rest state. 
         [0093]    The fourth stitch type  40  has a vertical extensibility which is inferior to that of the third stitch type  38 , and which is for example equal to one hundred and fifty percent of stretching relative to a rest state. 
         [0094]    Concerning the transverse elastic extensibility characteristics relating to different stitch types  28 ,  36 ,  38 ,  40 , the first stitch type  28  and the second stitch type  36  have a transverse extensibility lower than that of the third stitch type  38  and of the fourth stitch type  40 , which is for example of seventy five percent of stretching relative to a rest state. 
         [0095]    Finally, the transverse elastic extensibility of the third stitch type  38  and of the fourth stitch type  40  is, for example, of one hundred and seventy five percent of stretching relative to a rest state. 
         [0096]    Thus, the brassiere  10  according to the invention allows to get free from an added underwire. 
         [0097]    However, without limitation, the brassiere  10  according to the invention can be equipped with an added underwire to improve the chest holding. 
         [0098]    In addition, the disposition of the different portions  30   a,    30   b,    32   a,    32   b,    34   a ,  34   b  of each cup  12   a,    12   b  and of the stiffener  20 , as well as the mechanical characteristics of each stitch type  28 ,  36 ,  38 ,  40  allow to offer an optimal chest holding. 
         [0099]    According to a variant, not shown, the stiffener  20  surrounds the lower periphery of each cup  12   a,    12   b,  as well as a part of the upper periphery of each cup  12   a,    12   b,  to highlight the volume of the cups  12   a,    12   b.