KNITTED FABRICS WITH REDUCED EDGE ROLLING AND A METHOD FOR THEIR MANUFACTURING

Description

FIELD OF THE INVENTION

[0001] This disclosure relates to knit structures and methods for producing knit structures with a combination of stitches which provide force towards the inside of the knit structure and reduce curl outwards and subsequent roll over. Knit structures of this disclosure can be used as a replacement for double layer bands in articles of clothing such as, but not limited to, pantyhose, stockings, stay ups and socks.BACKGROUND OF THE INVENTION

[0002] A typical single jersey knit structure rolls over at its end due to the two faces of the fabric having unbalanced forces; this phenomenon increases when elastic yarns are used in the construction. Accordingly, single jersey knit structure ends are oftentimes folded by sewing or by creating a double layer of fabric during production.

[0003] Typically, hosiery and socks are produced in small single cylinders approximately 4 inches in diameter for hosiery and 3¾ inches for socks. At least one of the yarns used in the construction is usually elasticized. Examples include covered spandex or bare spandex. The first portion of the tube usually represents the upper band, welt or waist band. To prevent this portion from curling or rolling over during processing, wear and use, it is usually formed from a double layer of fabric. This double layer ranges in height from millimeters or several centimeters according to the chosen design and is generally machine-formed using dial jacks.

[0004] Typically, in socks, panty hose and stay ups which are also known as thigh highs, hold ups or stockings, produced on a single cylinder knitting machine where the knitted tube is not further sewn in its upper end, the knitted tube is likely to roll over if the double layer technique described above is not used. Ways to mitigate roll over without a double layer are to use a heavier count yarn combination to increase significantly the denier of the structure or to use a double cylinder machine or equivalent knit structures.

[0005] Specifically, stay ups which require application of silicon or high friction material on the knitted tube to help the garment keeping the position when worn, are generally produced with a band generated by means of dial jacks. Without using dial jacks to form a double band, the resulting single jersey knitted structure will likely roll over when worn.

[0006] There is a need for alternative knit structures and methods for producing knit structures which provide force towards the inside of a knitted tube and reduce outward curl and subsequent roll over.

[0007] US 3 600 909 A describes a footlet construction which involves an integrally knitted upper band fitting around the top of the footlet or socklet which need not be assembled from gores or stitching. The socklet is made on a circular knitting machine by using a turned-over top knitted of Lycra yarn on top of a body of nylon yarn. The loops on the elastic top are provided by knitting 30 to 60 courses and preferably about 50 courses on 200 needles with the intervening or alternating needles holding the initial stitch so that a tubular element will be formed serving as the upper elastic band or selvage of the footlet.

[0008] GB 513 615 A describes an article of hosiery in which the top portion is formed with a tubular elastic welt comprising a plurality of successive welt courses each containing substantially half the number of a normal course of the said top portion, the first welt course being united with alternate loops of an initial complete course of plain knitting with the remaining loops of the said initial course to form a tubular section, and in which a coiled elastic thread is enclosed in the said tubular section. It further describes a method of forming an article of hosiery having a tubular welt which comprises knitting a plurality of welt courses on to alternate loops of an initial complete course of plain knitting, winding an elastic thread around the fabric formed by the welt courses, knitting a complete course of plain knitting on to the remaining loops of the initial complete course and the loops of the last welt course to form a tubular welt enclosing the elastic thread, and knitting subsequent courses on to the last formed complete course of the welt to form the balance of the article.

[0009] US 3 908 407 A describes a ladies' knee-high stocking with supporting cuff. The supporting cuff is relatively wide and includes successive coursewise or horizontally extending bands with each of the bands including a single course of plain knit stitches of spandex yarn in every wale followed by a plurality of successive courses of stitch loops knit of stretchable yarn. Each of the bands includes walewise or vertically extending stripes of stitch loops having a contrasting appearance and formed by alternate and intervening groups of wales with alternate groups of wales including a pattern of tuck stitches interspersed in plain stitch loops. The spaced apart single courses of spandex yarn in the cuff are knit with the spandex yarn under sufficient tension that the stitch loops straighten out and form spaced apart inwardly extending ribs on the inner surface of the cuff to aid in supporting the upper end of the stocking on the leg of the wearer.SUMMARY OF THE INVENTION

[0010] The inventors herein have surprisingly found a stitch combination for production of the upper part of a knit structure which drastically reduces the rolling over of the fabric end thus allowing for the production of articles of clothing such as, but not limited to, pantyhose, stockings, stay ups and socks without using dial jacks and in general without creating a double layer. Or without the more tradition band with silicon that needs to be sewn on the knitted tube

[0011] Accordingly, an aspect of the present invention relates to a method for producing a knit structure with reduced outward curling and / or rolling at its fabric end. This method involves a knitting procedure which uses cylinder needles instead of dial jacks, which provides the inward force needed to reduce curl. The needles carry the yarn(s) and start a knit structure, referred to herein as the START part, which can extend multiple courses. The needles are then allocated into at least two sections. This usually occurs by means of a knitting program. The allocation is only general concept, in that some needles will make a certain type of stitch or stitch sequence and other needles may make another type of stitch or stitch sequence. The allocated sections include a knit needle section and a miss needle section, to produce a second section adjacent to the START part and referred to herein as the FALSE BAND. In each course of the FALSE BAND part, at least one needle of the knit needle section performs a knit stitch while at least one needle of the miss needle section performs a miss stitch. When the FALSE BAND part has reached the desired length, the needles of the miss needles sections start to knit and form what it referred to herein as the CLOSE part. Each needle in each course may perform a variety of stitch types depending upon the knitting program that is employed. Because of the miss needle sections of the FALSE BAND part, the last course of the START part is interconnected with the first course of the CLOSE part resulting in a knit structure with higher tension and force toward the inside, opposing the rolling over phenomenon without compromising the cross-stretch extension.

[0012] An additional yarn is included to further reduce tendency to curl and roll over at its edge. Typically, polyamide yarns having between 8 and 80 dtex are used in hosiery. The reason this yarn helps is because it increases the weight of the fabric of the CLOSE part with respect to the FALSE BAND part and help reducing roll over. However, the yarn composition is not limited to polyamide yarns, other types of yarns could be utilized depending upon the desired embodiment.

[0013] Another aspect of the present invention relates to knit structure comprising a combination of stitches which provide force towards the inside of the knit structure and reduce outward curl and subsequent roll over. In one embodiment the knit structure is produced on cylinder needles instead of dial jacks of the knitting machine. The knit structure comprises a START part extending one or more courses, a FALSE BAND part adjacent to the START part comprising multiple courses of knit stitch and miss stitch; and a CLOSE part of knit stitch extending one or more courses adjacent to the FALSE BAND. Because of the miss stitches of the FALSE BAND part, the last course or courses of the START part is interconnected with the first course or courses of the CLOSE part resulting in a knit structure with higher tension and force toward the inside, opposing the rolling over phenomenon without compromising the cross-stretch extension.

[0014] Another aspect of the present invention relates to an article of manufacture at least a portion of which comprises the knit structure of this invention. In one nonlimiting embodiment, the article of manufacture is an article of clothing. In one nonlimiting embodiment, the article of clothing is selected from pantyhose, stockings, leggings, stay ups and socks.BRIEF DESCRIPTION OF THE FIGURES

[0015] FIG. 1 is a nonlimiting example of a knit structure of this disclosure with stitch notation constructed using a 400 needle single cylinder hosiery knitting machine at 4 inch diameter and having 4 feeds. The rows represent the courses and the columns represent the needles. In this nonlimiting embodiment, "O" is a needle knitting a stitch; "X" is a needle missing a stitch; "." indicates the stitch is same as above; START part is 2 courses; FALSE BAND part is 8 courses; MISS sections are all equal and 1 needle long; and KNIT sections are all equal and 1 needle long. The START and FALSE BAND part are formed using 22 dtex spandex single covered with 17 dtex polyamide (PA). In the CLOSE part, a 33 by 2 dtex PA is plated in with the covered yarn. The rest of the hose part has the same structure as the CLOSE part. FIG. 2 provides a sketch of the knit structure constructed in FIG. 1. FIG. 3 provides another nonlimiting example of a knit structure of this disclosure wherein "O" represents a needle knitting a stitch; "X" represents a needle missing a stitch; DETAILED DESCRIPTION OF THE INVENTION

[0016] This invention relates to knit structures and methods for producing knit structures with a combination of stitches which provide force towards the inside of the knitted structure thereby reducing outward curling and subsequent roll over at its edge. Knit structures of this disclosure can be used as a replacement for double layer bands in articles of clothing such as, but not limited to, pantyhose, stockings, stay ups and socks.

[0017] Methods for reducing rolling over of the fabric end of a knit structure in accordance with the present invention involve a knitting procedure which uses cylinder needles instead of dial jacks of the knitting machine. The needles carry the yarn(s) and start a knit structure, referred to herein as the START part, which can extend multiple courses. In one nonlimiting embodiment, the START part only extends 1 to 8 courses, however in some embodiments the START part may be greater than 8 courses. The needles are ideally divided into at least two sections, a knit needle section and a miss needle section, to produce a second section adjacent to the START part and referred to herein as the FALSE BAND part or section. In each course of the FALSE BAND part, at least one needle of the knit needle section performs a knit stitch while at least one needle of the miss needle section performs a miss stitch. In one embodiment, each course of the FALSE BAND part, at least one needle of the knit needle section performs a knit stitch while all of the miss needle section performs a miss stitch. In one nonlimiting embodiment, each knit and miss needle section is different from other knit and miss needle sections of the structure. For example, in one embodiment a knit needle section may be of only one needle which knits; or may be of two needles one knitting one missing, with the course below having one missing and one knitting needle.

[0018] A miss section may be comprised of one section having only one needle missing; alternatively, two needles missing; or as extreme example could have even more than 3 needles missing. In one nonlimiting embodiment, the knit needle section and the miss needle section follow each other and this sequence repeats for all the needles of the cylinder. In one nonlimiting embodiment, there are only knit and miss needle sections extending one needle each in, for example, a 400 needle machine, in a pattern of one needle knit following by one needle miss for all 400 needles. When the FALSE BAND part has reached the desired length, e.g. 8 courses in total; or between 2 and 20, the needles of the miss needles sections will start to knit and form what it referred to herein as the CLOSE part. There is no limit to what length will make up the CLOSE part, for instance in some embodiments, the remainder of the garment can be considered to make up the CLOSE part. What is important is that in the first courses (for example, courses 1 to 4 or some other early courses) the needles of the miss needle section make a knit. Because of the miss needle sections of the FALSE BAND part, the last course (or courses, depending on the structure) of the START part will be then interconnected with the first course (or courses, depending on the structure) of the CLOSE part. The result is a fabric structure with higher tension and force toward the inside of the tube, opposing the rolling over phenomenon without compromising the cross-stretch extension.

[0019] An additional yarn is included to further reduce tendency to curl and roll over.

[0020] Knit and miss needle sections can vary in length and number of needles. In one nonlimiting embodiment, the sections comprise one needle each. Knit and miss needle sections are preferably subsequent but can be followed or preceded by other sections with stitch of different nature, for example tuck stitches or combinations of different stitches.

[0021] Knit structures in accordance with the present invention comprise a combination of stitches which provide force towards the inside of the knit structure and reduce curl outwards and subsequent roll over. In one embodiment, the knit structure is produced on cylinder needles instead of dial jacks. As shown in FIGs. 1 through 3, the knit structure comprises a START part extending one or more courses. Adjacent to the START part of the knit structure is a FALSE BAND part or section. The FALSE BAND section comprises multiple courses of knit stitch and miss stitch. In one nonlimiting embodiment, the FALSE BAND section comprises 8 courses. The knit structure further comprises a CLOSE part extending one or more courses adjacent to the FALSE BAND. Because of the miss stitches of the FALSE BAND part, the last course of the START part is interconnected with the first course of the CLOSE part resulting in a knit structure with higher tension and force toward the inside, opposing the rolling over phenomenon without compromising the cross-stretch extension.

[0022] Articles of manufacture in accordance with the present invention are comprised of at least a portion of the knit structures described herein. Nonlimiting examples of these articles include clothing such as, but not limited to, pantyhose, stockings, stay ups and socks. All standard garment processing steps are understood to be applicable to the fabric of the invention. (e.g. scour, dyeing, heat setting or boarding, application of softeners).

Claims

1. A method for producing a knit structure with reduced curling outward and / or rolling at its fabric end, said method comprising: carrying yarn using cylinder needles and knitting a START part of the knit structure extending one or more courses; dividing needles of the cylinder needles into at least two sections comprising a knit needle section and a miss needle section and producing a FALSE BAND section adjacent to the START part, said FALSE BAND comprising multiple courses of a knit stitch and a miss stitch; and starting needles of the miss needles sections to knit and form a CLOSE part adjacent to said FALSE BAND, wherein a course of the START part is interconnected with a course of the CLOSE part resulting in a knit structure with higher tension and force toward the inside, opposing the rolling over phenomenon without compromising the cross-stretch extension; characterised in that an additional yarn is included such that the weight of the fabric of the CLOSE part is increased with respect to the FALSE BAND part.

2. The method of claim 1 wherein the knit needle section and the miss needle section follow each other and this sequence repeats for all the needles of the cylinder.

3. The method of claim 1 wherein only knit needle sections and miss needle sections extending one needle each in a pattern of one needle knit followed by one needle miss produce the FALSE BAND section.

4. The method of claim 1 wherein a 400 needle machine is used.

5. The method of claim 1 wherein the FALSE BAND comprises 4 to 20 courses in total.

6. The method of claim 1 wherein the knit structure contains polyamide yarns having between 8 and 80 dtex.

7. A knit structure comprising a combination of stitches which provide force towards the inside of the knit structure and reduce curl outwards and subsequent roll over, said knit structure comprising: a START part extending one or more courses; a FALSE BAND part adjacent to the START part comprising multiple courses of knit stitch and miss stitch; and a CLOSE part extending one or more courses adjacent to the FALSE BAND, wherein a course of the START part is interconnected with a course of the CLOSE part resulting in a knit structure with higher tension and force toward the inside, opposing the rolling over phenomenon without compromising the cross-stretch extension; characterised in that an additional yarn is included such that the weight of the fabric of the CLOSE part is increased with respect to the FALSE BAND part.

8. An article of manufacture with at least a portion of which comprises the knit structure of claim 7.

9. The article of manufacture of claim 8 which is article of clothing.

10. The article of manufacture of claim 9 wherein the article of clothing is selected from pantyhose, stockings, stay ups and socks.

11. The method of claim 1 or the knit structure of claim 7, wherein the additional yarn is a polyamide yarn having between 8 and 80 dtex.