[Technical Field]
[0001] The present invention relates to water-repellent treatment of a high-strength fabric, and more particularly, to a method for treating high-strength fabric to be water-repellent. which can uniformly pick-up a water-repellent agent composition impregnated in the high-strength fabric while preventing the high-strength fabric from being wrinkled.
[0002] The high-strength fabric is a fabric woven by warp and weft, wherein at least one of the warp and weft includes a high-strength yarn such as wholly aromatic polyamide multifilament or carbon fiber, and widely used in manufacturing bulletproof garments or the like.
[0003] Water-repellent treatment of the high-strength fabric is generally executed to improve flexibility and water-repellency of the high-strength fabric and, when the bulletproof garments are manufactured using the high-strength fabric obtained by water-repellent treatment, wearing comfort and bulletproof properties can be remarkably enhanced.
[Background Art]
[0004] A conventional method for water-repellent treatment of a high-strength fabric mostly includes: dipping a woven and refined high-strength fabric in a water-repellent agent composition to impregnate the fabric with the water-repellent agent composition; conducting a padding process which includes squeezes the fabric to pick-up the water-repellent agent composition impregnated in the high-strength fabric using a mangle; and drying and heating the same in a tenter.
[0005] However, such a conventional method as described above adopts a padding mode of removing (that is, 'pick-up') the water-repellent agent composition impregnated in the high-strength fabric while passing the same, that is, the high-strength fabric impregnated with the water-repellent agent composition between two squeezing rollers, therefore, entails some problems such as wrinkling on the high-strength fabric, restriction in uniformly picking-up the water-repellent agent composition impregnated in the high-strength fabric, or the like.
[0006] Accordingly, the water-repellent fabric obtained by the conventional method has disadvantages such as poor flexibility and water-repellent performance, occurrence of wrinkles, or the like. Therefore, if bulletproof garments are manufactured using the same, water absorption due to reduced water-repellent performance has caused deterioration in bulletproof performance, and lack of flexibility has encountered a problem of reduced wearing comfort.
[Summary of the Invention]
[Problems to be Solved by the Invention]
[0007] In order to solve the conventional problems as described above, it is an object of the present invention to provide a new water-repellent treatment method of a high-strength fabric, capable of uniformly removing ('pick-up') a part of water-repellent agent components impregnated in the high-strength fabric while not occurring wrinkles on the same.
[Means for Solving the Problems]
[0008] In order to achieve the above object, there is provided a method for water-repellent treatment, which includes using an air-suction machine instead of a typical mangle used in the art, in order to uniformly pick-up a part of a water-repellent agent composition impregnated in a high-strength fabric during dipping.
[0009] Further, the present invention adopts a pre-drying process of the high-strength fabric, which is in wet state while passing a refining process, before dipping it in the water-repellent agent composition.
[Effects of the Invention]
[0010] According to the present invention, a part of the water-repellent agent composition impregnated in the high-strength fabric can be uniformly removed (picked-up) during dipping, therefore, water-repellent performance, specifically, both of water-repellency after friction and initial water-repellency may be enhanced, and occurrence of wrinkles on a high-strength raw fabric during water-repellent treatment may be effectively prevented.
[0011] As a result, the high-strength fabric obtained by water-repellent treatment according to the present invention does not have wrinkles but has increased flexibility to improve wearing comfort and, when this is used as a raw fabric for bulletproof garments, water-repellency may be increased to prevent reduction in bulletproof properties cause by water absorption.
[Modes for Carrying out the Invention]
[0012] Hereinafter, the present invention will be described in more detail.
[0013] First, a water-repellent treatment method of a high-strength fabric according to the present invention includes: dipping a high-strength fabric in a water-repellent agent composition to impregnate the fabric with the water-repellent agent composition; and using an air-suction machine to pick-up a part of the water-repellent agent composition impregnated in the high-strength fabric before drying and heating the same.
[0014] Herein, it is preferable that 35 to 65% of the water-repellent agent composition impregnated in the high-strength fabric is picked-up by using the air-suction machine, so as to improve flexibility and water-repellent performance of the high-strength fabric.
[0015] If a pick-up rate is less than 35%, further processes of drying and heating should be carried out for extended time to thus deteriorate flexibility. On the other hand, when the pick-up rate exceeds 65%, water-repellent performance and flexibility may be reduced due to lack of the water-repellent agent.
[0016] In this regard, the high-strength fabric in wet state (moisturized) while being subjected to a refining process is preferably pre-dried before dipping the same in the water-repellent agent composition, so as to increase a concentration of the water-repellent agent composition impregnated in the high-strength fabric in a following dipping process.
[0017] As described above, the present invention uses an air-suction machine, instead of the conventional mangle, in order to pick-up the water-repellent agent composition impregnated in the high-strength fabric. Accordingly, occurrence of wrinkles on the high-strength fabric during water-repellent treatment may be effectively prevented, as well as, the water-repellent agent composition impregnated in the high-strength fabric may be more uniformly removed (that is, picked-up).
[0018] More particularly, one embodiment of the water-repellent treatment method of a high-strength fabric according to the present invention may include: (i) refining a woven high-strength fabric; (ii) pre-drying the refined high-strength fabric; (iii) dipping the pre-dried high-strength fabric in a water-repellent agent composition; (iv) using an air-suction machine to uniformly pick-up a part of the water-repellent agent composition impregnated in the high-strength fabric obtained after the dipping process; and (v) drying and heating the resultant high-strength fabric in a tenter, wherein a part of the impregnated water-repellent agent composition was uniformly picked up from the fabric, thereby completing the water-repellent treatment of the high-strength fabric.
[0019] The high-strength fabric is a fabric textured of warp and weft wherein at least one of the warp and weft includes high-strength yarns such as wholly aromatic polyamide multifilament, glass fiber, carbon fiber, or the like.
[0020] The water-repellent agent composition may be a water-soluble solution containing hydroxylated perfluoroalkylethyl acrylate copolymer, however, a constitutional ratio of the water-repellent agent composition is not particularly limited.
[0021] Herein, a content of hydroxylated perfluoroalkylethyl acrylate copolymer in the water-repellent agent composition preferably ranges from 2 to 35 wt. parts to 100 wt. parts of the water-repellent agent composition.
[0022] A particular example of the water-repellent agent composition may be a water-repellent agent composition which includes: 1 to 5 wt.% water-soluble solution of a composition containing 25 to 35 wt.% of hydroxylated perfluoroalkylethyl acrylate copolymer, 10 to 15 wt.% of dipropylene glycol and 50 to 65 wt.% of water; and 0.1 to 1 wt. parts of silicon oil and 0.5 to 10 wt. parts of isopropylalcohol relative to 100 wt. parts of the water-soluble solution.
[0023] Hereinafter, the present invention will be more particularly understood by the following examples and comparative examples.
[0024] However, these examples are proposed for more concretely explaining the present invention, while not limiting the scope of the present invention.
Example 1
[0025] First, a 2.5 wt.% water-soluble solution of a composition including 30 wt.% of hydroxylated perfluoroalkylethyl acrylate copolymer, 15 wt.% of dipropyleneglycol and 55 wt.% of water was prepared. After adding 0.3 wt. part of silicon oil and 5 wt. parts of isopropylalcohol to 100 wt. parts of the above water-soluble solution, the mixture was sufficiently agitated to prepare a water-repellent agent composition. Then, a wholly aromatic polyamide fabric refined using a surfactant was dipped in the above water-repellent agent composition, to impregnate the wholly aromatic fabric with the water-repellent agent composition.
[0026] In this regard, the wholly aromatic polyamide fabric used in this example was a fabric woven in a plain form with each of warp and weft densities of 10 threads/cm by using wholly aromatic multifilaments as the warp and weft threads, each of which includes 1,000 wholly aromatic polyamide monofilaments having a fineness of 1.0.
[0027] Following this, using an air-suction machine has picked-up a part of the water-repellent agent composition impregnated in the wholly aromatic polyamide fabric, more particularly, at a pick-up rate of 60%. Then, the treated fabric was dried and heat treated in a tenter at 150°C for 1 minute.
[0028] Physical properties of the wholly aromatic polyamide fabric obtained by water-repellent treatment were evaluated and results thereof are shown in Table 1.
Example 2
[0029] The wholly aromatic polyamide fabric was subjected to water-repellent treatment according to the same process under the same conditions as described in Example 1, except that the refined wholly aromatic polyamide fabric was pre-dried at 180°C for 30 seconds before dipping.
[0030] Physical properties of the wholly aromatic polyamide fabric obtained by water-repellent treatment were evaluated and results thereof are shown in Table 1.
Comparative Example 1
[0031] The wholly aromatic polyamide fabric was subjected to water-repellent treatment according to the same process under the same conditions as described in Example 1, except that a part of the water-repellent agent composition impregnated in the wholly aromatic polyamide fabric was removed (that is, picked-up) at a pick-up rate of 60% using a mangle instead of an air-suction machine.
[0032] Physical properties of the wholly aromatic polyamide fabric obtained by water-repellent treatment were evaluated and results thereof are shown in Table 1.
[TABLE 1]
Results of evaluating physical properties |
Items | Example 1 | Example 2 | Comparative Example 1 |
Initial water-repellency |
90 |
100 |
90 |
Water-repellency after rubbing 100 times |
90 |
100 |
80 |
Stiffness (kgf) |
0.50 |
0.35 |
0.65 |
Occurrence of wrinkles within 20 m of fabric obtained after water-repellent treatment |
Not occurred |
Not occurred |
Occurred |
[0033] Physical properties stated in the above Table 1 were evaluated to the following procedure.
Occurrence of wrinkles
[0034] Visual observation by experts was executed to monitor and determine occurrence of wrinkles.
Measurement of stiffness
[0035] After cutting off each of the fabrics obtained by water-repellent treatment according to the above examples and comparative example into pieces, to prepare a sample having a size of 100 mm × 200 mm. Then, the prepared sample was subjected to measurement of stiffness by a circular-bend method according of ASTM D 4032. More particularly, the sample was folded in half and placed on a strut with a size of 102 mm × 102 mm × 6 mm, which has a punched hole having a diameter of 38.1 mm. Next, when pressing the sample down using a bar, a force of pushing the fabric down through the 38.1 mm hole was measured to determine the stiffness.
Measurement of initial water-repellency
[0036] After cutting off each of the fabrics obtained by water-repellent treatment according to the above examples and comparative example into pieces, to prepare a sample having a size of 250 mm × 250 mm. Then, the prepared sample was subjected to measurement of initial water-repellency by a spray method according of ISO 4920:1981.
Measurement of water-repellency after friction
[0037] After cutting off each of the fabrics obtained by water-repellent treatment according to the above examples and comparative example into pieces, to prepare a sample having a size of 250 mm × 250 mm. Then, the prepared sample was rubbed 100 times using a shiefer type wear tester SAT-250. After completion of the rubbing, the sample was subjected to measurement of water-repellency after friction by a spray method according of ISO 4920:1981.
[Industrial Applicability]
[0038] The high-strength fabric obtained by water-repellent treatment according to the present invention exhibits excellent wearing comfort and bulletproof properties, thereby being effectively useable as raw materials of bulletproof garments.
1. A method for treating high strength-fabric to be water-repellent, comprising: dipping the high-strength fabric in a water-repellent agent composition to impregnate the high-strength fabric with the water-repellent agent composition; and using an air-suction machine to pick-up a part of the water-repellent agent composition impregnated in the high-strength fabric, before drying and heating the same.
2. The method according to claim 1, wherein the high-strength fabric is firstly pre-dried and then dipped in the water-repellent agent composition.
3. The method according to claim 1, wherein 35 to 65% of the water-repellent agent composition impregnated in the high-strength fabric is picked-up by using the air-suction machine.
4. The method according to claim 1, wherein the water-repellent agent composition is a water-soluble solution containing hydroxylated perfluoroalkylethyl acrylate copolymer.
5. The method according to claim 4, wherein a content of hydroxylated perfluoroalkylethyl acrylate copolymer in the water-repellent agent composition ranges from 2 to 35 wt. parts to 100 wt. parts of the water-repellent agent composition.
6. The method according to claim 1, wherein the high-strength fabric is a fabric woven by warp and weft wherein at least one of the warp and weft includes one high-strength yarn selected from a group consisting of wholly aromatic polyamide multifilament, glass fiber and carbon fiber.