JP2005194633A - Wet-heat resistant woven or knitted fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a woven or a knitted fabric suitable for a medical textile product carrying out a sterilization treatment with high-temperature industrial washing or high-temperature steam (an operating gown, a drape, a white gown, etc.), a clothes material, a shoe material, a curtain, a sheet, etc., and having excellent wet heat resistance. <P>SOLUTION: The wet-heat resistant woven or knitted fabric comprises a synthetic fiber consisting essentially of polyethylene terephthalate. The woven or knitted fabric after dyeing finishing is mainly composed of a yarn having ≤25 equivalents/ton content of carboxyl end groups and 1.33-1.40 relative viscosity. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention has excellent moisture and heat resistance suitable for medical textile products (such as surgical clothes, drapes, lab coats, or sheets) that are sterilized by high-temperature washing or high-temperature steam, working uniforms, clothing materials, shoe materials, or curtains. It relates to woven and knitted fabrics.

Polyester fibers are used in a wide variety of applications in terms of excellent mechanical properties, easy care properties, durability and cost performance. However, the polyester fiber has a problem that the wet heat strength is low due to its polymer characteristics. In other words, since it is a polycondensation reaction product of dicarboxylic acid and diglycol, the hydrolysis reaction proceeds directly when exposed to high temperature in an environment where moisture is present. In applications where high temperature washing or steam sterilization is applied, such as lab coats, surgical clothes, sheets used in hospitals, and heavily worn work clothes, product damage often occurs due to repeated processing. It was. Even in home laundry, when the washing temperature is set to a high temperature of 80 ° C. or higher, products made of polyester fibers are very damaged.
In order to solve the above-mentioned problem that the polyester fiber has poor heat and heat resistance, it has been proposed to reduce the amount of carboxyl terminal groups of the polyester and improve the heat and heat resistance by using an end-group blocking agent. Various end group blocking agents such as carbodiimide compounds and oxazoline compounds have been proposed. Normally, the end group blocking agent is added during the polymerization process or melt spinning process, so that the newly generated alcohol end group is gelled, which reduces the degree of polymerization of the polyester and sufficiently improves the hydrolysis resistance of the polyester fiber. However, various end-group blocking agents have been studied, and 2,6,2 ', 6'-tetraisopropyldiphenylcarbodiimide has been found to solve the above-mentioned problems ( For example, see Patent Document 1).
Japanese Patent Laid-Open No. 06-294011

  However, the problem caused by the unreacted end group blocking agent remaining in the polyester fiber has not been solved yet. In other words, this unreacted end group blocking agent lowers the dyeing quality of the woven or knitted fabric, and in the intermediate set before dyeing or the finishing set after dyeing, it becomes a bad odor gas and deteriorates the working environment. The introduction of equipment for gas countermeasures (air conditioning equipment) left the issue of increasing costs.

  The present invention has been made in view of the current situation, medical textile products (such as surgical clothes, drapes, lab coats or sheets) subjected to high temperature washing or sterilization with high temperature steam, clothing materials, shoe materials, It is a technical object to provide a woven or knitted fabric excellent in dyeing quality and moisture and heat resistance suitable for curtains or working uniforms.

  As a result of intensive investigations to solve the above problems, it is difficult to eliminate the unreacted end group blocking agent. To solve the problem due to the presence of the unreacted end group blocking agent, the end group blocking agent The use of polyester fibers with specific performance and characteristics under the belief that it is important not to use high resistance to high temperature washing and steam sterilization, and sufficient absolute strength The inventors have found that a woven or knitted fabric satisfying the requirements can be obtained, and have reached the present invention.

That is, the present invention
(1) A woven or knitted fabric containing synthetic fibers mainly composed of polyethylene terephthalate whose end groups are not blocked with a carboxyl end group blocking agent, and the woven or knitted fabric after dyeing finish has a carboxyl end group amount of 25 eq / ton or less, A moisture and heat resistant woven or knitted fabric having a relative viscosity of 1.33 to 1.40.
(2) Moisture and heat resistant fabric according to (1), wherein the tensile strength retention after 80 washings at 80 ° C. is 80% or more and the tensile strength retention after 15 hours of steaming is 80% or more. .
(3) Moisture and heat resistant knitted fabric according to (1), wherein the bursting strength retention after 80 washings at 80 ° C is 80% or more and the bursting strength retention after 15 hours of steam treatment is 80% or more .
(4) A medical textile product using the woven or knitted fabric according to (1), the woven fabric according to (2) or the knitted fabric according to (3).
(5) A working uniform using the woven or knitted fabric according to (1), the woven fabric according to (2) or the knitted fabric according to (3).
Is a summary.

  As in the present invention, by using a woven or knitted fabric containing a polyester-based synthetic fiber mainly composed of polyethylene terephthalate in which a compound having the ability to block carboxyl end groups is not used as a carboxyl end group blocking agent, dyeing spots, etc. Factors that adversely affect the dyeing quality can be eliminated, and the amount of carboxyl end groups of the polyester synthetic fiber after dyeing finish is controlled to 25 eq / ton or less to suppress hydrolysis of the polymer, and sterilization with high temperature washing or high temperature steam. On the other hand, excellent durability can be obtained. Furthermore, it can have a favorable mechanical characteristic by making the relative viscosity of the polyester-type synthetic fiber after dyeing finish into 1.33-1.40.

  Further, it is possible to provide a woven or knitted fabric suitable for medical textile products (such as surgical clothes, drapes, lab coats or sheets), clothing materials, shoe materials, curtains or working uniforms that are sterilized by high temperature washing or steam. Become.

Embodiments of the present invention will be described below.

  The woven or knitted fabric of the present invention is a woven or knitted fabric containing a polyester-based synthetic fiber mainly composed of polyethylene terephthalate, and the polyethylene terephthalate has isophthalic acid, succinic acid, adipic acid, 1,3 propanediol, 1,4-butanediol, 1,6 hexanediol, bisphenol or the like may be copolymerized. In the present invention, it is important that a compound having the ability to block carboxyl end groups is not used as a carboxyl end group blocking agent in this polyester synthetic fiber.

  In the woven or knitted fabric of the present invention, the amount of carboxyl terminal groups of the polyester synthetic fibers constituting the woven or knitted fabric after dyeing finish is required to be 25 eq / ton or less, and more preferably 20 eq / ton. When the carboxyl end group amount exceeds 25 eq / ton, the wet heat durability is remarkably inferior, and the object of the present invention cannot be achieved. In terms of performance, the smaller the amount of carboxyl end groups, the better, but considering the cost, the lower limit is usually about 10 eq / ton.

  Furthermore, in the woven or knitted fabric of the present invention, it is necessary that the relative viscosity of the polyester-based synthetic fiber constituting the woven or knitted fabric after dyeing finish is 1.33 to 1.40, and is 1.35 to 1.38. Is more preferable. If the relative viscosity is less than 1.33, the strength of the woven or knitted fabric itself is lowered, or the thermal deterioration of the polymer proceeds, so that the strength is lowered in the steps after the dyeing process. In addition, in order to obtain a woven or knitted fabric having a relative viscosity exceeding 1.40, the degree of polymer polymerization of the polyester synthetic fiber constituting the woven or knitted fabric must be increased, and the single fiber fineness of the polyester synthetic fiber is increased. Thus, the single fiber fineness (0.1 to 5.0 dtex) suitable for medical fiber products and working uniforms, which are the main uses of the woven or knitted fabric of the present invention, cannot be obtained.

  Further, in order to suppress the amount of carboxyl end groups after dyeing finish as in the present invention, for example, a method in which a polymer mainly composed of low-viscosity polyethylene terephthalate is subjected to solid-phase polymerization at high temperature and reduced pressure and then spun. Polyester fibers produced by the above method may be used.

  In the woven or knitted fabric of the present invention, good wet heat resistance can be obtained because the fibers after dyeing finish have the above-mentioned characteristics. Usually, surgical clothes, drapes or sterilized cloth used in hospitals or pharmaceutical-related factories are sterilized by high-pressure steam. The steam treatment at that time is generally wet heat treatment at 135 ° C. However, a woven or knitted fabric composed of ordinary polyester fibers is subjected to a steam treatment of about 80 times, resulting in a significant decrease in strength due to hydrolysis. Met. At this time, since one steam treatment time at 135 ° C. is 4 to 8 minutes, the average treatment time is 6 minutes, which corresponds to about twice as much as 7 hours treatment corresponding to 70 treatments. It is preferable that the tensile strength retention of the woven fabric is 80% or more based on the time treatment time. In the case of a knitted fabric, the burst strength retention is preferably 80% or more.

  On the other hand, even in high-temperature laundering, the strength of ordinary polyester fibers is reduced. Usually, industrial washing is performed at a temperature of 70 to 80 ° C., and is used repeatedly at least 100 times. Therefore, the woven or knitted fabric of the present invention is a fabric tension when 100 times of high temperature washing at 80 ° C. is used as a reference. The strength retention is preferably 80% or more, and in the case of a knitted fabric, the burst strength retention is preferably 80% or more.

  In the present invention, it is not necessary that all the fibers constituting the woven or knitted fabric after dyeing finish are polyester fibers having the above-mentioned characteristics, but the proportion of the polyester fibers in the entire woven or knitted fabric is 80% by mass or more. Preferably there is. When the proportion of the polyester fiber is less than 80% by mass, the woven or knitted fabric is not preferable because durability against high-temperature washing or sterilization by high-temperature steam and mechanical properties after dyeing finish are deteriorated.

  In the present invention, the above-mentioned polyester fiber can be used in combination with other fibers, or by combining fibers such as cross-twisting, blending or blending. Furthermore, the form of the fiber may be long fiber or short fiber. Moreover, in the case of a long fiber, it may be a shaped yarn using a false twisted yarn or a stuffer box.

  In the woven or knitted fabric of the present invention, the structure is not particularly limited, and in the case of a woven fabric, flat, twill, satin or double woven fabric, and in the case of a knitted fabric, tenji, kago or interlock are listed. .

Medical textile products such as surgical gowns, drapes, lab coats, duvet covers or sheets using the above-mentioned moist and heat-resistant woven and knitted fabrics, even when sterilized by high-temperature washing or high-temperature steam, have little decrease in strength and excellent durability It is a thing. In addition, working uniforms, clothing materials, shoe materials, curtains, and the like using the moisture-and-heat-resistant woven or knitted fabric described above are less durable and excellent in durability even when subjected to high-temperature washing.
(Example)

  Next, the present invention will be specifically described with reference to examples.

In addition, the processing method and performance measuring method of the woven / knitted fabric in the examples are shown below.
1) Treatment method of woven or knitted fabric a) Steam treatment Using a high-pressure steam sterilizer HV-50 (Hirayama Seisakusho Co., Ltd.), it was treated at 135 ° C. and a pressure of 225 kPa for 15 hours.
B) Using a rotary washer manufactured by High-temperature Laundry Suga Test Co., Ltd., the detergent concentration is 10 g / liter, the water temperature is 80 ° C., 10 minutes is one wash, the washing water is drained, and then the water is washed at 40 ° C. for 5 minutes This was carried out 100 times in succession, with one rinse being one rinse.
2) Method for measuring performance of woven and knitted fabric a) Tensile strength and elongation of woven fabric The woven and knitted fabric was measured by a constant speed elongation method according to the method A of JIS L-1096.
The tensile strength retention was calculated by the following formula.
Tensile strength retention rate (%) = (Tensile strength after treatment / Tensile strength before treatment) × 100
B) Bursting strength of knitted material Measured according to JIS L-1018 method A.
The burst strength retention was calculated by the following formula.
Burst strength retention rate (%) = (Burst strength after treatment / Burst strength before treatment) × 100
C) After cutting the woven or knitted fabric so that 0.1 g of carboxyl terminal group polyester synthetic fiber is contained, the polyester synthetic fiber is extracted from the cut sample, and the extracted polyester synthetic fiber is added to 10 ml of benzyl alcohol. After dissolution, 10 ml of chloroform was added to this solution, and titrated with a 0.1 N potassium hydroxide benzyl alcohol solution to determine the amount of carboxyl end groups.
D) Relative viscosity of woven or knitted fabric The sample was dissolved using a mixture of equal mass of phenol and ethane tetrachloride as a solvent, and measured with an Ubbelohde viscometer at a concentration of 0.5 g / dl and a temperature of 20 ° C.

50 kg of an oligomer with an average degree of polymerization of 7 and an esterification reaction rate of 95% obtained by continuous ester reaction between terephthalic acid and ethylene glycol was transferred to a polymerization tank, and 11.4% by mass of ethylene glycol was added to this oligomer. Then, after esterification at 240 ° C. for 1 hour, the temperature was raised to 280 ° C., and 2 × 10 ⁻⁴ mol of antimony trioxide was added as a catalyst with respect to 1 mol of the acid content. Thereafter, the pressure was reduced to 5 hPa or less over 1 hour, and a polycondensation reaction was further performed for 1.5 hours to obtain a prepolymer chip having a carboxyl end group amount of 15 eq / ton. This chip was subjected to solid phase polymerization at 235 ° C. under reduced pressure for 24 hours to obtain a polyethylene terephthalate chip having a carboxyl end group amount of 9 eq / ton.
The obtained chip was spun at a temperature of 290 ° C. to obtain a semi-undrawn yarn of 122 dtex 72f wound at a speed of 3250 m / min. Subsequently, the temperature of the second roller was 80 ° C., the heater plate temperature was 170 ° C., and the draw ratio was 1.452 to obtain a drawn yarn of 84 dtex 72f.
The drawn yarn thus obtained was used for warp and weaved in a water jet loom to obtain a plain woven fabric with a warp density of 142 / 2.54 cm and a weft density of 90 / 2.54 cm. Subsequently, scouring was conducted by a conventional method, followed by presetting at 170 ° C. for 30 seconds using a tenter, and 2% o. m. After dyeing in the dyeing bath at 130 ° C. for 30 minutes, a finishing set is performed in a tenter at 180 ° C. for 1 minute, and the finishing density is warp density 150 / 2.54 cm, weft density 98/2. A 54 cm fabric of the invention was obtained.

  Except for setting the polycondensation reaction time to 2.5 hours, a polycondensation reaction was performed in the same manner as in Example 1 to obtain a prepolymer chip having a carboxyl end group amount of 25 eq / ton. This chip was subjected to solid phase polymerization at 235 ° C. for 20 hours under reduced pressure to obtain a polyethylene terephthalate chip having a carboxyl end group amount of 18 eq / ton. Using the obtained chip, a drawn yarn of 84 dtex 72f was obtained under the same spinning conditions and drawing conditions as in Example 1. The obtained drawn yarn was woven and dyed in the same manner as in Example 1 to obtain a woven fabric of the present invention having the same finishing density as in Example 1.

(Comparative Example 1)
A prepolymer chip having a carboxyl end group amount of 27 eq / ton was obtained in the same manner as in Example 1 except that the amount of ethylene glycol added was 2.5% by weight. Using the resulting prepolymer as it was, a 122 dtex 72f semi-undrawn yarn was spun under the same conditions as in Example 1, and an 84 dtex 72f drawn yarn was obtained under the same drawing conditions as in Example 1. The obtained drawn yarn was woven in the same manner as in Example 1 and dyed and finished to obtain a comparative fabric having the same finishing density as in Example 1.

(Comparative Example 2)
A polycondensation reaction was carried out in the same manner as in Example 1 except that the average degree of polymerization was set to 6 to obtain a prepolymer chip having a carboxyl end group amount of 15 eq / ton. This chip was subjected to solid phase polymerization at 235 ° C. under reduced pressure for 24 hours to obtain a polyethylene terephthalate chip having a carboxyl end group amount of 9 eq / ton. Using the obtained chip, a drawn yarn of 84 dtex 72f was obtained under the same spinning conditions and drawing conditions as in Example 1. The obtained drawn yarn was woven in the same manner as in Example 1 and dyed and finished to obtain a comparative fabric having the same finishing density as in Example 1.

  A 122 dtex 72f semi-undrawn yarn spun in Example 1 was used as a feed yarn, false twisting was performed under the conditions of a yarn speed of 120 m / min, a draw ratio of 1.48, a heater temperature of 200 ° C., and a false twist number of 3500 T / M, and 84 dtex 72f. Of false twisted yarn was obtained.

  Using the obtained false twisted yarn, an interlock circular knitted fabric is knitted with a 28 gauge, 33 inch circular knitting machine, followed by scouring by a conventional method, and disperse dye 2 using a liquid dyeing machine. % O. m. Dyeing at 130 ° C for 30 minutes in the dye bath of f, and finishing set at 180 ° C for 1 minute with a tenter, round knitting of the present invention with 42 wales / 2.54 cm, 50 courses / 2.54 cm I got the ground.

(Comparative Example 3)
Using the 122 dtex 72f semi-undrawn yarn spun in Comparative Example 1 as a supply yarn, false twisting was performed at the same draw ratio, heater temperature, and false twist number as in Example 3 to obtain an 84 dtex 72f false twisted yarn.

  Using the obtained false twisted yarn, an interlock circular knitted fabric was knitted with a 24 gauge, 33 inch circular knitting machine, and then scouring, dyeing, and finishing set were performed in the same manner as in Example 3 to produce 42 wales. A circular knitted fabric of a comparative example of /2.54 cm and 50 course / 2.54 cm was obtained.

  Table 1 shows the evaluation results of the obtained Examples 1 to 3 and Comparative Examples 1 to 3.

表１より明らかなように、実施例１〜３の織編物は、構成糸の製造において末端基封鎖剤を用いていないため、織編物の染色加工工程で悪臭ガスが発生せず、作業環境に悪影響を及ぼすことがなかった。また、いずれも染色品位についても問題ないものであった。さらに、実施例１〜３の織編物は湿熱処理に対しても優れた強力保持性を示しており、高温の工業洗濯や高圧の蒸気処理が施されるワーキングユニフォームや医療用繊維製品に適していた。
一方、染色後のカルボキシル末端基量の大きい比較例１および比較例３は、湿熱処理に対する強力保持性が著しく低いものであった。また、相対粘度の低い比較例２の織物は、強度保持性は満足するものの染色仕上げ工程中の受熱により初期引張強力が低く、絶対強度不足であった。

As is clear from Table 1, the woven or knitted fabrics of Examples 1 to 3 do not use an end-group blocking agent in the production of the constituent yarns, so no odorous gas is generated in the dyeing process of the woven or knitted fabric, and the working environment is improved. There was no adverse effect. In addition, there was no problem with the dyeing quality. In addition, the woven and knitted fabrics of Examples 1 to 3 show excellent strength retention even in wet heat treatment, and are suitable for working uniforms and medical textile products subjected to high-temperature industrial washing and high-pressure steam treatment. It was.
On the other hand, Comparative Example 1 and Comparative Example 3 having a large amount of carboxyl end groups after dyeing had remarkably low strength retention against wet heat treatment. Moreover, although the fabric of Comparative Example 2 having a low relative viscosity was satisfactory in strength retention, the initial tensile strength was low due to heat reception during the dyeing finishing process, and the absolute strength was insufficient.

Claims (5)

  A woven or knitted fabric comprising polyester-based synthetic fibers mainly composed of polyethylene terephthalate whose end groups are not blocked with a carboxyl end-group blocking agent, and the amount of carboxyl end groups of the polyester-based synthetic fibers after dyeing finish is 25 eq / ton or less And a wet and heat resistant woven or knitted fabric having a relative viscosity of 1.33 to 1.40.   The moisture and heat resistant fabric according to claim 1, wherein the tensile strength retention after 80 washings at 80 ° C is 80% or more and the tensile strength retention after 15 hours of steam treatment is 80% or more.   The moisture and heat resistant knitted fabric according to claim 1, wherein the rupture strength retention after 100 washings at 80 ° C is 80% or more, and the rupture strength retention after 15 hours at steam treatment is 80% or more.   A woven or knitted fabric according to claim 1, or a medical fiber product using the woven fabric according to claim 2 or the knitted fabric according to claim 3. A working uniform using the woven or knitted fabric according to claim 1 or the woven fabric according to claim 2 or the knitted fabric according to claim 3.