JPH0369649A - Cotton/polyester fiber composition and bat - Google Patents

Abstract

PURPOSE: To obtain a batt having resistance to repeated washings by blending cotton with copolyester binder fibers having a specific melting point in a specified proportion, forming the resultant blend into a batt, heating the formed batt at a specific temperature, softening the binder fibers and bonding the fibers at points of intersection. CONSTITUTION: This blend is obtained by mixing 75-85 wt.% of cotton fibers (preferably having 1.6 denier fineness and 0.8-1.5 inches length) with 15-25 wt.% of copolyester binder fibers having 230-340 deg.F (preferably having a fineness of 0.75-2.7 times based on that of the cotton fibers and a length of 0.75-2.0 times based on that of the cotton fibers), forming the resultant mixture into a batt, heating the formed batt at 230-390 deg.F for 20-100 s, softening the binder fibers and bonding the fibers at points of intersection. The resultant low-density batt has >2.0 pound-inches per oz/yd.<2> adjusted total work-to-break and <0.038 g/cm<3> density and is excellent in bulkiness.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to blends of cotton and polyester copolymer fibers and batts made from the blends. The batts are manufactured by a thermal bonding process and they are sufficiently resistant to withstand the stress of repeated cleaning. The formulation is bulky and low density.

SUMMARY OF THE INVENTION In summary, a formulation, a batt, and a method of making the batt from the formulation are disclosed. The formulation and batt are made of cotton and 230-340” F.
It is manufactured from a homogeneous composition with copolyester binder fibers having a melting temperature of .

U.S. Patent 4°685 issued August 11, 1987
．． No. 914 (Personal Products) teaches the production of absorbent pads by thermally melting a composition of absorbent fibers and binder fibers.

Absorbent fibers can be wood pulp, rayon, cellulose acetate, flax, hemp, jute, ramie, cotton, and the like. The binder fiber is polyester. Pads using blends of polyester staple and polyester binder fibers and blends of acrylic fibers and polyester binder fibers have about 20-25% binder fibers and have a temperature of about 315°F'. combined.

European Patent Publication 227.914 appears to teach the coagulation of cotton swabs by superficially melting thermoplastic fibers that are uniformly distributed throughout the cotton.

The temperature for melting appears to be about 250°F'.

Japanese Publication J60029182A available in abstract format
(Torre) and J60040239A (Kanegafuchi)
teaches the production of blends of fibers and melting of the blends by thermal means. The fibers can be selected from a list of relatively high melting point materials including polyester, polypropylene, polyacrylics, cotton, wool, flax, rayon, etc., as well as a list of binders including copolyesters, polyolefins, etc.

U.S. Pat. No. 4,769, issued September 6, 1988.
022 (3M) teaches the production of pads made by heating a 50,150 weight percent cotton and polyester blend to 285°F for 20 seconds.

Polyester staples for thermally bonded nonwovens (
Polyester 5taple for Ther
mally BondedNonwovens), W.
Kwok et al., Nonwoven Industry, July 1988, teach that certain polyester binder fiber products can be used to produce thermally bondable blends of fibers. ing.

The present invention consists of 75-85% by weight of cotton and 60% terephthalate.
- ethylene terephthalate/iso7 tallate copolyester 1 consisting of 80 mol % and 20-40 mol % inphthalate and having a melting point of about 230-340 aF.
The present invention provides a thermofusible blend of fibers containing a homogeneous mixture of 5-25% by weight.

The present invention also includes a method of melting the above-described formulation by heating the above formulation to a temperature of about 230-390 DEG F' for about 20-100 seconds under non-pressure. The present invention also includes a batt made from the above process having a density of 0.014-0.038 grams per cubic centimeter and capable of withstanding the stress of repeated cleaning.

The present invention relates to the use of cotton fibers in blends with other fibers such as copolyester binder fibers. Despite the fact that the formulation contains cotton fibers that are not thermofusible, it also contains thermofusible binder fibers that can cause bonding between adjacent fibers by heating and melting. can. The present invention is a method of making improved batts of high quality, low density and excellent durability using cotton staple.

Cotton staples are obtained from commercially available raw materials, which may be washed or unwashed and bleached or raw.

For purposes of the present invention, cotton may be ordinary wood pulp or may be regenerated cellulose, such as rayon.

Copolyesters suitable for use in the practice of this invention are those prepared from a 1 mole to mole condensation of ethylene glycol and a composition of terephthalic acid and isophthalic acid. For such a copolyester with a terephthalate/isophthalate molar ratio of 70/30, it has a melting point of about 288°F and a
It has a fixation point of °F'. Fibers made from this copolyester function as thermal binder fibers and must exhibit a melting point below the temperature at which cotton discolors, as well as exhibit melt adhesion to cotton staples.

The fibers used in this invention are used in the form of a blend, and the fibers in the blend must be selected to properly interact upon transformation of the blend into a resistant batt.

One important factor in the interaction is the relative dimensions of the cotton fibers and binder fibers.

The cotton fibers have a denier of 1.0-1.8, preferably about 1.6, and lengths of 0.8-1.5 inches have been found preferred. The binder fibers should have approximately the same denier as that of the cotton stable, but if they are somewhat different they should be 0.75-2.7 times that of the cotton. . The length of the binder fibers can range from 0.5-3 inches, but it is preferred that the binder fibers are 0.75-2.0 times the length of the cotton staples in a given formulation. .

Cotton fibers and copolyester fibers can be combined in any commercial bleaching equipment. Of course, the fibers can also be combined by other effective means, so long as the blend results in a homogeneous mixture of different fibers.

It should be pointed out that the formulations of the present invention are not limited only to cotton and copolyester fibers. If desired or necessary for any reason, further fibers can be added to the formulation and this further fiber can also provide an active effect or be present simply as a filler material. . Other fibers may be hollow or solid, and may be inorganic or organic, natural or synthetic. Additives other than fibers can also be added to the formulation as fillers, colorants, fragrances, antimicrobials, bulking agents, flame retardants, antistatic agents, and the like. In the case of additive substances, it has been found that they should generally be used in amounts of 0.1-20% by weight, based on the total weight of the formulation. In the case of additives that provide an active effect in the formulation, the amount of fiber should be selected to achieve the desired purpose.

The formulations of the present invention contain 15-25% by weight of copolyester binder fibers based on the total weight of fibers in the formulation. Blends made with less than 15% copolyester binder fibers will not bind to provide adequate resistance under any conditions, and blends made with more than 25% copolyester binder fibers will fail. Resulting in a bonded batt that exhibits poor wash resistance. As disclosed in the abutment technique, the binder material need only be present as a surface component of the binder fibers, such as the sheath component of a sheath/core bicomponent fiber. The remainder of the fiber, or core, may be of high melting point and will therefore remain in the fiber form as a crosslinked structure after the low melting point material has melted and provided its binding action. Such bicomponent binder fibers are described, for example, in U.S. Pat.
disclosed inside. In order to obtain good results when using bicomponent fibers, it is recommended to adjust the proportions accordingly somewhat in order to optimize the results with respect to the preferred proportions when blending the -component binder fibers with cotton. be done.

The formulation can be molded into the batt of the present invention on a single layer of the formulation or it can be stacked in several layers. A curd- or pomegranate-shaped web of the formulation is typically produced by cross-overlapping the web on a moving apron to a desired batt thickness as disclosed in U.S. Patent No. 3,290.704. Form a bat from several layers of. After shaping, the batt is heated to a temperature above the bonding temperature of the binder fibers to soften the fiber binders and cause them to adhere to each other and to the cotton fibers in the batt. Heat release, air inlet drum or furnace, infrared heater,
It can be supplied by a radiation heater, etc. The heat should not exceed the cotton discoloration temperature, about 390° F., and is preferably somewhat lower. The temperature of the heat should be as low as possible, and for that reason copolyesters with a low melting point are used. In actual operation, 3
The bonding temperature below 60-380 is high. The heating period must be suitable for the binder fibers to soften and bond, and is generally 20-100 seconds or perhaps longer. Heating on the batt is generally carried out without pressure, in order to try to produce batts with as low a density as possible. However, the batt may be heated under some pressure to obtain a batt of desired density for a particular purpose.

The batt of the present invention can be used for fibrous fillers, insulation, badging, resilient cushioning, etc.

Bats are generally 0.0 per cubic centimeter.
18 - Manufactured to have a density of 0.038 grams. These batts exhibit excellent cleanability and have high strength as indicated by large values of adjusted total actuation failure. Cleanability is a measure of the batt's resistance to automatic cleaning and drying cycles. Batts with too few binder fibers will disintegrate during washing due to inadequate fiber-to-fiber adhesion, and batts with too many binder fibers will be too hard and brittle to break apart during washing. It was discovered that After washing, the batts of the present invention have a superior appearance to batts manufactured using the same type of materials and under the same conditions but having less than 15% by weight or more than 25% by weight copolyester binder fibers. It was showing.

The test methods used to measure these properties are shown below.

Test Method Denier - The denier of a filament is calculated from its fundamental resonant frequency, which is measured by vibrating a 2-4 cm length of filament under tension at varying frequencies. (A S TMD 157 Fu 66.25 parts, 1968).

Density - The density of a batt is determined by weighing a batt of known volume.

Fixation Temperature - Fiber fixation temperature is determined by Beaman and Cramer, The Journal of Polymer Science (J, Polymer 5c).
21.228 (1956). A flat brass ingot is electrically heated to slowly increase the ingot temperature. The fiber samples were suspended between glass rods on and near the surface of the mass under slight tension. At intervals, the fibers are brought into continuous contact with the heated mass for 5 seconds.
It was pressed using a 00 g brass weight. Fiber fixation temperature is the temperature of the mass when the fibers are fixed to the mass for at least 2 seconds after the weight is removed.

Actuation Break - The strength of the bat of the present invention is measured by measuring the adjusted total actuation failure.

The adjusted total actuation failure is determined by ASTM D as follows:
885-85.

Cut the bat to be tested 1 inch wide and 1 inch long. Ten of these samples are cut to length in the machine direction and ten to length in the transverse direction. Condition the samples for 2 hours at approximately 75'F and 55% relative humidity.

Each sample is placed in the jar of a tensile test machine having a gauge length of 5 inches and the sample is pulled and the results are recorded on the Kerr strain curve produced by the test machine.

Operating breakdown is calculated using the following formula: Operating breakdown, lb-ft - AXFXE [where: 8 - Area under the load-elongation curve, in. 2F = Load scale factor on drawing, in., and E - 1 in.] The elongation scale factor of the elongation of the test specimen per drawing of , in inches] The actuation failure is the average value of 10 specimens. Actuation failure is measured in the machine direction and in the transverse direction.

The total working failure is the sum of the working failure in the machine direction and the working failure in the lateral direction.

To calculate the adjusted working breakdown, divide the total working breakdown by the bat's basis weight in ounces/yd2. For purposes of this invention, an acceptable bat exhibits an adjusted total operating failure of greater than 2 inch-pounds per ounce/yd2.

Appearance After Washing - A major consideration with the batt of the present invention is its resistance to washing stress.

A test for such resistance is AATCC Test Method 13.
5-1987 (AATCC stands for American Association of Textile Chemists and Colorers 8). In conducting this test, three 8 x 8 inch test bats are used for each bat being tested. Laundry is carried out in an automatic wash and dryer according to the AATCC process, using regular or cotton settings for the washer, cotton settings for the dryer, and a 4.0 A load of pounds was used. A total of 5 cycles of washing and drying were used to complete the test.

The samples are judged according to their appearance on a scale of 1-4, where 1 is the worst, - has tangled fibers and shows non-uniformity, and 4 is the best. , has an excellent appearance with uniformity similar to the unwashed original sample. A bat appearance rating of 2.5 is considered acceptable for purposes of this invention.

Description of preferred embodiments Example 1. Preparation of the Blend In this example, a blend of fibers was prepared in accordance with the present invention.

Cotton stables that had been washed and bleached and had a denier of about 1.6 and an average length of about 1.1 inches (range 0.8-1.5 inches) were used.

Terephthalate and inphthalate groups in a 70/30 molar ratio with ethylene, a sticking point of 194°F', and 288
A copolyester binder fiber with a melting point of 0.5°F was used. The binder fibers had an average length of about 3 denim and about 1.5 inches.

The cotton fibers and copolyester fibers were combined and compounded in a commercial opener compounder so that the blend was uniform and the concentration of binder fibers was varied in each of several runs.

These several experiments are identified in the table showing the results of the examples.

Example 2. Batt Production In this example, the formulation from Example 1 was heat bonded to produce a batt of the invention.

The formulation from Example 1 was applied to a 40 inch roller top
Cursing on a carving machine produced a continuous web that was cross-overlapping into continuous batts having a basis weight of 3 to 8 ounces per square yard.

The batts were placed on a conveyor and passed through a 2 meter long air inlet oven at various speeds and at various temperatures.

Temperatures and rates for thermal bonding were 230-420°F' and 1.3-5 meters/minute.

The bats were tested for adjusted total actuation failure and bat appearance. The test results are shown in Table I below.

Bonding Experiment Temperature Number (F) Binder 10% 1 300 1.29 2 310 1.29 3 320.1.29 4 330 1.29 5 340 1.29 6 350 1.29 7 360 1.29 8 370 1 .29 9 370 2.26 10 370 5.00 11 380 1.29 12 390 1.29 13 400* 1.29 14 410* 1.29 15 420* 1.29 16 420* 2.26 17 420 pieces 3 .10 18 420* 5.00 Combined Basal Weight Velocity (oz/ Adjusted Total Actuation Batt (m/
Min.) Yard 2) Section + Machine - Total Exterior surface work 0.6240.7101.334 1.0160.8751.892 1.0620.9141.977 1.2111.1582.369 1.3711.1632.534 1. 0571.0832.139 1.2271.4272.653 1.4591.7603.218 1.1711.0702.242 0.5050.5151.020 1.5091.5533.061 1.9881.3883.376 1.4701 .6393.110 1.4941.8243.317 1.7301.8533.583 1.5881.5673.156 1.7431.9463.688 0.8090.8091.618 2.3 2.2 2.3 2. 3 Table I (Continued) Bond Bond Base Weight Experiment Temperature Speed (Ounce/1 Sectioned Total Actuation Batt Number (F) (m/min) Yard 2) Section + Machine - Total Appearance Binder 20% 19 280 1.29 20 290 1.29 21 300 1.29 22 310 1.29 23 320 1.29 24 330 1.29 25 340 1.29 26 350 1.29 27 360 1.29 28 370 1.29 29 380 1.29 30 390 1.29 31 400* 1.13 32 410* 1.29 33 420* 1.29 34 420 pieces 2.26 35 420 pieces 3.10 36 420* 5.00 1.2491.4542.703 1. 0850.9632.048 1.4351.1602.595 1.6111.5073.118 1.2811.2782.559 1.7451.4313.176 1.7361.8903.626 1.8932.3044.197 2.3522 .2664.619 2.2062.4714.678 2.4082.3834.791 2.8062.4665.273 2.3532.1464.499 3.2812.9356.216 3.0633.1936.256 2.3722. 4854.857 2.0321.9643.996 1.7891.5143.302 2.8 3.5 2.2 3.5 3.5 Binding Binding experiment Temperature Speed 1.29 1.29 1.29 1.29 1 .29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 1.29 2.26 5.00 TABLE I (CONTINUED) BASE WEIGHT (Ounces/Adjusted Total Actuation Bat 0.8920
．． 7721.665 1.30.9920.9451
．． 938 1.0371.0852.122 1.1451.0152.161 1.0441.0052.049 0.7691.2772.047 3.21.219
1.2942.513 1.6461.6083.254 13331.5172.849 2.01.4081
．． 4812.889 1.6361.4613.097 1.3720.8492.221 2.31.481
0.8862.368 1.7061.1542.860 2.0311.6013.632 2.31.963
1.5643.527 2.6502.0924.742 2.2942.4104.704 33.2152.
8106.025 2.9102.8885.797 6.6205.01211.632 2.8792.9575.836 2.82.298
1.6563.954 3.21.6161.477
3.093 2.8* indicates that the temperature was too high and the cotton changed color during processing.

The main features and aspects of the invention are as follows.

1.75-85% by weight cotton and 15-25% by weight 23
A thermofusible blend of fibers (bl
end).

2. The cotton fiber is 1-1.8 denier and the length is 0.
．． 8-1.5 inches, and the binder fibers are 0.75-2.7 times the denier of the cotton and 0.75-2.0 times the length of the cotton, and 80/20. -60/4
The formulation of 1 above, which is an ethylene terephthalate/isophthalate copolyester having a molar ratio of terephthalate to inphthalate of 0.

3. The formulation of 2 above, wherein the copolyester has a molar ratio of terephthalate to inphthalate of 70/30.

4.75-85% cotton and 15-25% 23% by weight
In a method of making a durable batt from a blend of fibers that is a homogeneous mixture with copolyester binder fibers having a melting point of 0-340° F', the blend is formed into a batt and the batt is heated to 230° F. -3
A method comprising heating to a temperature of 90°F for 20-100 seconds to soften the binder fibers and bond the fibers at the intersection points.

5. The method of 4 above, wherein the binder fiber is an ethylene terephthalate/isophthalate copolyester having a molar ratio of terephthalate to inphthalate of 80/20-60/40.

6. The method of 5 above, wherein the copolyester has a molar ratio of terephthalate to inphthalate of 70/30.

7. In the batt, the binder fibers are irregularly bonded with other fibers at intersection points and adjusted total work-to
-break) greater than 2.0 lb-in per ounce/yd2 and density less than 0.038 grams per cubic centimeter, 75-85% by weight
A batt of a homogeneous mixture of cotton and 15-25% by weight of copolyester binder fibers having a melting point of 230-340''F.

8. 7. The batt of claim 7, wherein the binder fiber is an ethylene terephthalate/isophthalate copolyester having a molar ratio of terephthalate to inphthalate of 80/20 to 60/40.

9. The batt of 8 above, wherein the copolyester has a terephthalate to inphthalate molar ratio of 70/30.

10. The batt has a better appearance after washing than a batt manufactured using the same types of materials and under the same conditions but having less than 15% by weight or more than 25% by weight of copolyester binder fibers. bat.

Claims (3)

[Claims] 1. 75-85% by weight cotton and 15-25% by weight 2
A thermofusible blend of fibers comprising a homogeneous mixture with copolyester binder fibers having a melting point of 30-340°F. 2. 75-85% by weight cotton and 15-25% by weight 2
In a method of making a resistant batt from a blend of fibers that is a homogeneous mixture with copolyester binder fibers having a melting point of 30-340°F, the blend is formed into a batt and the batt is heated to a temperature of 230-390°F. 20-100 to temperature
A method comprising heating for seconds to soften the binder fibers and bond the fibers at the intersection points. 3. In the batt, the binder fibers are irregularly bonded to other fibers at intersections and the adjusted total working breakdown is greater than 2.0 pounds-inch per ounce/yd and the density is per cubic centimeter. 0.0
Less than 38 grams, 75-85% cotton by weight and 15
- Batt of a homogeneous mixture with 25% by weight copolyester binder fibers having a melting point of 230-340°F.