BACKGROUND OF THE INVENTIONDenim is a sturdy cotton warp-faced twill textile in which the weft passes under two or more warp threads. This twill weaving produces the familiar diagonal ribbing of the denim that distinguishes it from cotton duck.
It is a characteristic of most indigo denim that only the warp threads are dyed, whereas the weft threads remain plain white. As a result of the warp-faced twill weaving, one side of the textile then shows the blue warp threads and the other side shows the white weft threads. This is why blue jeans are white on the inside. The indigo dyeing process, in which the core of the warp threads remains white, creates denim's fading characteristics, which are unique compared to other textiles.
After being made into an article of clothing, as part of the manufacturing process, most denim articles are washed to make them softer and to reduce or eliminate shrinkage (which could cause the article to not fit properly after its owner washes it). In addition to being washed, “washed denim” is sometimes artificially distressed to produce a “worn” look. Much of the appeal of artificially distressed denim is that it resembles dry denim which has faded. In jeans made from dry denim, such fading is obtained as a result of the jeans being worn by a person by the activities of his or her daily life. This process creates what many enthusiasts feel to be a more “natural” look than the look of artificially distressed denim.
Most dry denim is made with 100% cotton and comes from several different countries. In particular USA, Zimbabwe and Japan are popular sources of cotton for making raw denim. Some prefer the denim of one country to another for its purported durability, fades, and feel. Dry denim also varies in weight, typically measured in by the weight of a yard of denim in ounces. 12 Oz. or less is considered light denim, 12 Oz. to 16 Oz. is considered mid-weight, and over 16 Oz. is considered heavy weight. Heavier denim is much more rigid and resistant to wear. Jeans having a broken in look with vintage characteristics such as destruction (the wear and tear of threads), natural worn in whiskers at the crotch area (created by bending over and over) and the fading down of the natural deep dark indigo, has been a popular trend for many years. This worn in look is created by the natural wear and tear of raw denim that fades and destructs in time.
In the early 60's spandex was invented and resulted in a stretch yarn that could be woven into the mix of cotton yarn to create what are referred to as stretch denims. Stretch denim revolutionized the denim industry by enabling the manufacture of tight fitting jeans that were soft and comfortable. However, the stretch yarn used does not destruct and provide the desired vintage, worn in look.
As a result, it has not been possible to produce jeans which paired the characteristics of being able to produce the worn look with a stretch, tight fitting jean. Although combining a rigid jean material with a stretch jean material is not in and of itself a problem, manufacturers have determined that it is not possible to make such a combined product due to the different shrinkage factors of the two fabrics when combined in one garment. Rigid denim has a much different shrinkage percentage than the stretch denim. The different shrinkage percentages results in puckering of the sides where the two different materials are attached which is not an acceptable result.
In order to address the problem in the prior art, a specific blend of fibers and different size yarns is needed to overcome this problem, that is, jeans need to be manufactured using a using a rigid fabric front and a stretch fabric back while maintaining the same character and shrinkage factors for both. In this connection, according to the invention, a rigid fabric using 100% cotton yarn for the front is used to match the fabric used for the back of the jeans while maintaining the same character and shrinkage factors. The 100% cotton yarn is blended with a filament fiber polyester and a small amount of spandex all in the same size yarn to keep the shrinkage consistent between the front and the back. In this manner the front of the jeans can be stressed to provide a worn look while the back of the jeans made of the stretch material produces a tight, but comfortable fit without any puckering at the seams where the two materials are sewn together.
The invented jeans are a combination having a front portion made of a rigid jean material and a back portion made of a stretch jean material. However, in order to obtain a finished product where the two portions have the same character and shrinkage factors, a specific combination of yarns used to make the two portions is necessary. The rigid front of the garment is composed of a denim fabric made as follows:
A. The fabric composition is 100% cotton;
B. The weave construction has a yarn count of 10+10RSB*10;
C. The warp portion of the weave is spun with a combination of open-end spinning and ring spinning with a thread count of 28 threads/cm;
D. The weft portion of the weave is spun with open-end spinning with a thread count 20 threads/cm;
E. The resulting cotton fibers are sulfur dyed; and
F. The constructed weave goes through a singeing process to obtain a uniform and smooth fabric surface, then is pre-shrunk.
The stretch back of the garment is composed of a denim fabric made as follows:
A. The fabric composition is 79% cotton, 20% filament fiber polyester, 1% spandex;
B. The weave construction has a yarn count of 10+9RSB*150 D/40 D+150 D/40 D 83*60;
C. The warp portion of the weave is spun using a combination of open-end spinning and ring spinning with a thread count of 33 threads/cm;
D. The weft portion of the weave is made from the filament fiber polyester. There are two types of polyester yarn, filament and spun. In an embodiment, a filament yarn that combines enough fibers to obtain a tensile strength of 176.3 lbf (pounds per force) is used. The thread count of the filament yarn is 23.6 threads/cm. In another embodiment, the filament fiber polyester is spun using a spinneret;
E. The fibers are indigo dyed; and
F. The constructed weave goes through a singeing process to obtain a uniform and smooth fabric surface, and then is pre-shrunk.
After the front and back portions are obtained, the two materials are cut and sewn together in a manner well known in the art to produce pair of jeans. Pockets, a zipper or zippers and buttons can be added using well known prior art techniques to obtain a finished product.