MXPA00001878A - Melamine fiber-containing fabrics with improved comfort - Google Patents

Abstract

Fabrics containing melamine fibers are rendered more comfortable by carding the melamine fibers under vacuum so as to exhibit a narrower fiber diameter distribution (*d) and/or a narrower staple length distribution (*1) as compared to melamine fibers which are carded in the absence of vacuum. In addition, more comfortable melamine fiber-containing yarns are produced by spinning the staple fiber at a lower twist multiplier (TM) as compared to conventional melamine fiber yarns. Most preferably, the melamine fiber-containing fabrics and yarns will be blended with at least one other type of synthetic fibers, such as aramid fibers.

Description

FABRICS CONTAINING MELAMINE FIBER, WITH IMPROVED COMFORT DESCRIPTION The present invention relates generally to the field of melamine fibers. In specific forms, the present invention is incorporated in blends of melamine fibers with other synthetic fibers (eg, aramid fibers) that exhibit improved tactile feel and thus improved comfort when employed in garment fabrics. The melamine-based raw material fibers, due to the method by which they are produced, contain raw material fibers of different lengths and diameters. During the cutting and sewing of garments and when the goods contain melamine fibers wear out, there is the potential because (i) fibers of larger diameter are projected from the fabric and / or (ii) fibers of shorter lengths come off of the genres and fall into the skin of a person. In each case, it can result in physical discomfort. In accordance with the present invention, more comfortable fabrics containing melamine fibers are made. Broadly, therefore the present invention is incorporated into fabrics that include melamine fibers with improved tactile feel and thus greater comfort. In accordance with the present invention, the melamine fibers are vacuum-blended to exhibit a narrower fiber diameter distribution (* d) and / or a narrower raw material length distribution (*?) Compared to fibers of melamine that are carded in the absence of vacuum. In addition, yarns centrifuged from this melamine raw material fiber will have a lower twist multiplier TM = Twist Multiplier) compared to conventional melamine fiber yarns. These and other aspects and advantages of the present invention will become clearer upon careful consideration of the following detailed description of the preferred exemplary embodiments. The term "fibers" as used herein is intended to refer to fibers of raw material of various lengths. The term "twine" is a continuous strand of loosely assembled fibers without twisting. A "wick" is a twine that has been condensed for presentation to a spinning frame of "raw material" fibers (i.e. before twisting a yarn.) The melamine fibers that can be employed in the present invention are those produced from of highly concentrated solutions of melamine-formaldehyde pre-condensation products, after addition of an acidic curing agent, by rotocentrifugation, stretching, extrusion or fibrillation The fibers obtained are generally pre-dried with or without stretching and the resin Melamine is usually cured from 120 ° C to 250 ° C. The fibers are usually from about .3 to about 8 deniers and from about 11.7 mm (.5") to about 203.2 mm (8") in length. Thermal fibers of raw material are obtained when up to 30% by mol, in particular from 2 to 20% by mol of the melamine in the melamine resin is replaced by a hydroxyalkyl melamine.These fibers have a temperature of use sustained up to 200 ° C, preferably up to 220 ° C. In addition, minor amounts of melamine can be replaced by substituted melamines, urea or phenol. The melamine fibers are more preferably mixed with another synthetic yarn in order to achieve the desired yarn properties. Preferably, however, the melamine fibers are mixed with aramid fibers, as described more fully in U.S. Pat. No. 5,560,990 granted to Ilg et al. (All the content of which is expressly incorporated herein by reference). More specifically, the melamine fibers will be present in the blends in an amount between about 5 to about 95 parts by weight, with aramid fibers present in an amount between about 95 to about 5 parts by weight. The fibers of melamine and any other mixed fibers are subjected to a carding process that eliminates the fibers of raw material of greater length and greater diameter. Specifically, according to the present invention, the melamine fibers are subjected to carding under the influence of vacuum so that at least about 90% and more typically at least about 95% of the melamine fibers in the resulting raw material will have a length of raw material fiber between about 25.4 mm (1.0") to about 127.0 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per filament (Dpf). More preferably, carding is achieved using a conventional Truetzschler carding system. The resulting twine can then be formed into a wick that can be presented to the spinning frame. In this aspect, the twisted yarn of the wick most preferably has a twist multiplier (TM) value of less than about 4.0, and more preferably less than about 3.5. The value of the twist multiplier "is equal to the twist per 2.54 cm (1") (dpi) of the yarn, divided by the square root of the yarn size in the cotton count.

A further understanding of the invention is achieved from its following non-limiting example. EXAMPLE Torrals were formed from a mixture of melamine resin fibers (Basf Corporation's BAS0FIL7 fibers) and aramid fibers (KEVLAR7, DuPont fibers) by carding the mixture into respective carding systems in the absence (the "control") and under the influence ("the invention") of vacuum. After carding, the resulting twists are stretched twice to improve mixing and orientation. At each stretch stage, eight to ten ends of carded twines meet and reduce to a twine about the size of each individual twine. The reduced twine is then formed into a low twist oriented wick that is presented to the braid frame. The wicks were braided in a short braid ring braid of "cotton system" by reducing them to a desired yarn count and then adding a certain degree of twisting. Two strands of filaments are then twisted into layers together. The properties of the control filaments or filaments and of the invention are set forth in the following table. In this regard, yarn counts of single yarns were an estimate from the yarn or two-layer yarn (ie yarn count of single yarns was considered to be half the yarn count of two layers) . In addition, twists per 2.54 cm (1") of each single yarn were estimated based on the fact that two-layered yarn twists are typically 60% of single yarn twisting.

Genres of the same construction were produced from the two-layer yarns. In this regard, a flat weft ripstop construction is employed, with a gender weight of approximately 212.6 grams (7.5 oz) per square of yarn. The ripstop construction includes two ends or assembled after every eight ends or inserted into the normal flat web, to create a slightly raised square pattern in the fabric, thus providing the feel to the fabric, and being scratchy, even more noticeably apparent . The fabric produced from the control yarn gave a feeling of raw material, while the fabric made from the yarn of the invention had a softer, more uniform feel. It was also noted that garments made from the yarn genre of the invention are not only less scratchy but also have significantly shorter short fibers and / or yarns or wigs during the production of the garment. While the invention has been described in connection with what is currently considered to be the most practical and preferred embodiment, it should be understood that the invention shall not be limited to the described modality but on the contrary, it is intended to cover various modifications and assemblies. equivalents included within the spirit and scope of the appended claims.

Claims (21)

1. - A yarn including melamine fibers, wherein at least 90% of the melamine fibers have a length of raw material fibers from about 25.4 mm (1.0") to about 127.0 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per yarn.

2. - A yarn according to claim 1, characterized in that it has a twisting value or mulier of less than about 4.0.

3. - A yarn according to claim 1, characterized in that it has a twisting value or mulier of less than about 3.5. 4. - A yarn according to claim 1, characterized in that at least about 95% of the melamine fibers have a raw material fiber length of between about 25.

4 mm (1.0") to about 127 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per yarn.

5.- A thread in accordance with the claim 1, characterized in that it also comprises at least one other type of synthetic fibers.

6. A yarn according to claim 5, characterized in that the other type of synthetic fibers includes aramid fibers.

7. - A yarn according to claim 6, characterized in that the melamine fibers are present in an amount between about 5 and about 95 parts by weight and wherein the aramid fibers are present in an amount between about 95 and about 5 parts by weight. weight.

8. - A fabric including a yarn of any one of claims 1 to 7.

9. A fabric that includes a yarn containing melamine fibers having a value of a twisting mulier of less than about 4.0 and wherein at least 90 % of melamine fibers have a length of raw material fibers of between about 25.4 mm (1.0") and approximately 127.0 mm (5.0") and a diameter between approximately 0.3 and approximately 4.0 dpf.

10. - A sort of according to claim 9, characterized in that the yarn has a value of the twisting mulier less than about 3.5.

11. A fabric according to claim 9, characterized in that at least about 95% of the melamine fibers have a raw material fiber length of between about 25.4 mm (1.0") to about 127.0 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per yarn.

12. - A fabric according to claim 9, characterized in that the yarn also comprises at least one other type of synthetic fibers.

13. - A fabric according to claim 12, characterized in that the other type of synthetic fibers includes aramid fibers.

14. - A fabric according to claim 12, characterized in that the melamine fibers are present in an amount between about 5 and about 95 parts by weight and wherein the aramid fibers are present in an amount between about 95 and about 5. parts by weight.

15. - Method for producing a melamine-containing genus, characterized in that it comprises the steps of: (i) melamine fibers as raw material under the influence of vacuum to obtain a twist where at least about 90% of the melamine fibers they have a length of raw material fibers of between about 25.4 mm (1.0") to about 127.0 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per yarn; (ii) spinning the twine to form a yarn having a twisting mulier value of less than about 4.0; and (iii) forming the yarn into a yarn.

16. The method according to claim 15, characterized in that step (i) includes mixing the melamine fibers with at least one other type of synthetic fibers

17. The method according to claim 15, characterized in that before step (i) it is practiced to mix the melamine fibers with at least one other type of synthetic fibers

18. The method according to claim 16 or 17, characterized in that at least one other type of synthetic fibers include aramid fibers.

19. - The method according to claim 18, characterized in that the mixing step includes mixing melamine fibers in an amount between about 5 and about 95 parts by weight with aramid fibers in an amount between about 95 to about 5 parts in weight.

20. The method according to claim 15, characterized in that step (i) is practiced in such a way that at least 95% of the melamine fibers have a fiber length of raw material of between about 25.4 mm (1.0"). ) to approximately

127. 0 mm (5.0") and a diameter of between about 0.3 to about 4.0 denier per yarn -

21. The method according to claim 15, characterized in that step (ii) is practiced to form a yarn having a twisting multiplier value less than about 3.5.