JP2017166102A - Polyester-based fiber structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester-based fiber structure having effectively modified surface layer and excellent in hydrolysis resistance.SOLUTION: The polyester-based fiber structure is a fiber structure consisting of a polyester-based fiber of which a part of carboxyl group terminals is sealed, and has a ratio of CN-/C- intensity at a depth of 1 nm from a fiber surface to CN-/C- intensity at the depth of 5 nm in a depth profile measurement by a flight time type secondary ion mass spectrometry (TOF-SIMS) in a range of 3.0 to 6.0.SELECTED DRAWING: None

Description

  The present invention relates to a polyester fiber structure excellent in hydrolysis resistance.

  In recent years, environmental awareness has increased, and in order to reduce plastic waste and to suppress global warming, it is a social responsibility that companies should fulfill in order to reduce carbon dioxide emissions. In order to solve these problems, it is important to promote recycling and reuse.

  Polyester fibers are a widely used material, but hydrolyzability has often been a problem. In the hydrolysis reaction of the polyester fiber, the proton released from the terminal carboxyl group acts as an autocatalyst and promotes the decomposition of the ester, causing a decrease in strength. In particular, uniforms in fields such as medical care, nursing care and foods require washing in a hot water bath at a temperature of 60 to 90 ° C and autoclave treatment at a temperature of 120 to 130 ° C. ) Is a concern. Therefore, in the current state of uniforms in the medical field, there are problems that the years of use are relatively short and the ratio of disposable items is high.

  Therefore, by providing technology that improves the hydrolysis resistance of polyester fibers, it is possible to achieve longer life of uniforms that require washing at high temperatures and autoclaving, thereby solving environmental problems. The possibility of being able to do so is expected.

  As means for suppressing the hydrolysis of polyester, a method of reducing the terminal carboxyl group concentration by adding a terminal blocking agent has been proposed (see Patent Documents 1 and 2). However, since these methods knead and add the end-blocking agent to the polymer chip before spinning, the end-blocking agent causes fuming due to evaporation and decomposition at a high temperature during spinning, generating a bad odor and toxic gas. There is. For this reason, there is also a problem that an end-capping agent must be added excessively. Furthermore, the spinnability deteriorates and the productivity also decreases.

  In addition, it has been proposed to use an inorganic substance as a terminal blocking agent (see Patent Document 3). Although this proposal can solve the problem of toxic gases during kneading and spinning, it is difficult to change the yarn type due to the end-capping treatment at the spinning stage, and it is difficult to change the type of dyeing and post-processing. There is concern that decomposition will occur.

  As another solution, a method in which the end-capping agent is dissolved in a solvent or emulsified with an emulsifier is brought into direct contact with the object to be treated to add end-capping to the surface of the object to be treated. (See Patent Document 4). However, this proposal is a treatment method for polylactic acid, and if it is polylactic acid, it may be modified to the vicinity of the surface. However, the hydrolysis resistance to high temperature and long-term wet heat is insufficient.

  Furthermore, as a method for improving the hydrolysis resistance against wet heat over a long period of time, it is desirable to modify the surface layer portion including the surface of the structure in direct contact with wet heat. A method of applying a terminal blocking agent to the inside of a structure has been proposed (see Patent Document 5). However, in this proposal, since the exhaustion efficiency of the end-capping agent to the object to be treated is low, it is necessary to increase the use concentration in order to impart hydrolysis resistance to high-temperature wet heat. There exists a subject that the cost which concerns becomes high.

  When a polyester fiber is treated with a processing liquid containing a fiber function-imparting agent, a method in which a carrier is allowed to coexist in the processing liquid has been proposed (see Patent Document 6). There are only water repellents, water absorbents, flame retardants, etc., and it does not describe what effect the carrier has on the end-capping agent, nor has it been specifically studied. .

  Further, a method has been proposed in which a grafting treatment is performed by exhausting a polymerization initiator in a bath using a phthalimide compound (see Patent Document 7). It is not described whether it brings about an effect.

  Further, a combination of a carrier agent and an end-blocking agent has been proposed (see Patent Document 8). Here, an end-blocking agent is applied to the fiber surface and inside. However, this proposal has a large amount of diffusion to the inside and is not concentrated on the surface layer. Therefore, although it can provide sufficient hydrolysis resistance to a fiber structure with a small fineness, it is sufficient for a fiber structure with a large fineness. However, local modification of the surface layer was a problem.

JP 2001-261797 A JP 2002-30208 A JP 2010-189813 A JP 2009-249450 A JP 2009-263840 A JP 2001-98459 A JP 2000-226765 A Special table 2012-81596 gazette

  Accordingly, an object of the present invention is to provide a polyester fiber structure excellent in hydrolysis resistance in which a surface layer portion is efficiently modified in view of the above-described conventional background art.

  The present invention aims to achieve the above object, and the polyester fiber structure of the present invention is a fiber structure comprising polyester fibers in which the carboxyl group ends are partially blocked, and has a flight time. In depth profile measurement by type secondary ion mass spectrometry (TOF-SIMS), the ratio of CN− / C−intensity at a depth of 1 nm to CN− / C−intensity at a depth of 5 nm from the fiber surface is A polyester fiber structure characterized by being in the range of 3.0 to 6.0.

  According to a preferred embodiment of the polyester fiber structure of the present invention, the fiber structure made of the polyester fiber is a fiber structure made of an aromatic polyester fiber.

  According to a preferred embodiment of the polyester fiber structure of the present invention, the carboxyl group terminal is partially blocked with a carbodiimide compound.

  According to a preferred embodiment of the polyester fiber structure of the present invention, the carbodiimide compound is a compound represented by the following general formula (I).

Wherein R1 is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an allyl group, and an aralkyl group having 7 to 20 carbon atoms. Represents at least one group selected from the group consisting of:
According to a preferred embodiment of the polyester fiber structure of the present invention, the carbodiimide compound includes N, N′-di-2,6-diisopropylphenylcarbodiimide, N, N′-dicyclohexylcarbodiimide and N, N ′. -At least one compound selected from the group consisting of diisopropylcarbodiimide.

  According to the present invention, a polyester fiber structure capable of efficiently imparting a carbodiimide compound to the fiber structure surface layer and imparting high hydrolysis resistance to a fiber structure containing polyester fibers. Is obtained.

  As a result of intensive studies on improving the hydrolysis resistance of a fiber structure composed of polyester fibers, the present invention improves hydrolysis resistance by blocking the carboxyl group terminals of the surface layer portion of the polyester fibers. It has been found that it can be.

  The polyester fiber structure of the present invention is a fiber structure composed of polyester fibers in which the carboxyl group ends are partially blocked, and depth profile measurement by time-of-flight secondary ion mass spectrometry (TOF-SIMS). The ratio of the CN- / C-intensity at a depth of 1 nm to the CN- / C-intensity at a depth of 5 nm from the fiber surface is a polyester fiber structure having a ratio of 3.0 to 6.0.

  The polyester fiber in the present invention means one having an ester bond in a molecular chain, and aliphatic polyester and aromatic polyester are preferably used.

  Examples of aliphatic polyesters include polyesters obtained by condensing aliphatic dicarboxylic acids and aliphatic diols, poly (D-lactic acid), poly (L-lactic acid), and copolymers of D-lactic acid and L-lactic acid. , D-lactic acid and hydroxycarboxylic acid copolymer, L-lactic acid and hydroxycarboxylic acid copolymer, DL-lactic acid and hydroxycarboxylic acid copolymer, or blends thereof Etc. Among these, from the viewpoint of versatility, polylactic acid mainly composed of L-lactic acid and apexa which is an environmentally friendly polyester marketed by DuPont are preferably used.

  Here, L-lactic acid as a main component means that 50% by mass or more of the aliphatic polyester is L-lactic acid. In addition, the aliphatic polyester is allowed to have a part of the terminal carboxyl groups blocked by adding a terminal blocking agent during spinning.

  Examples of the aromatic polyester include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polytrimethylene naphthalate, and polybutylene naphthalate. These aromatic polyesters are also allowed to contain other copolymer components.

  As copolymer components for polyester, dimer diol for improving alkali hydrolysis resistance, glycol component for improving color development, polyfunctional phosphorus compound for imparting flame retardancy, and imparting cationic dyeability And sulfoisophthalate for the purpose.

  As the dimer diol, specifically, PESPOL HP-1000 manufactured by Toa Gosei Co., Ltd. (hydrogenated dimer diol having 36 carbon atoms and an alicyclic type / linear aliphatic type = 75/25 (mol%)) Etc.

  In addition, as the glycol component, specifically, ethylene oxide is added to a compound such as 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, bisphenol A, bisphenol S and the like. Examples thereof include an added diol compound, a copolymer of propylene oxide and ethylene oxide, and polyoxyalkylene glycol.

  Specifically, dimethyl phenylphosphonate, diphenyl phenylphosphonate and the like are preferably used as the polyfunctional phosphorus compound. Phosphinates include, for example, (2-carboxyethyl) methylphosphinic acid, (2-methoxycarbonylethyl) methylphosphinic acid methyl, (2-carboxyethyl) phenylphosphinic acid, (2-methoxycarbonylethyl) phenylphosphinic acid methyl Phosphates such as methyl (4-methoxycarbonylphenyl) phenylphosphinate, ethylene glycol ester of [2- (β-hydroxyethoxycarbonyl) ethyl] methylphosphinic acid, and (1,2-dicarboxyethyl) dimethylphosphine oxide , (2,3-dicarboxypropyl) dimethylphosphine oxide, (1,2-dimethoxycarbonylethyl) dimethylphosphine oxide, (2,3-dimethoxycarbonylethyl) dimethylphosphine oxy And phosphine oxides such as [1,2 di (β-hydroxyethoxycarbonyl) ethyl] dimethylphosphine oxide, and [2,3 di (β-hydroxyethoxycarbonyl) ethyl] dimethylphosphine oxide.

  Specific examples of the sulfoisophthalic acid salt include alkali metal salts of sulfoisophthalic acid, phosphonium salts of sulfoisophthalic acid, and ester-forming derivatives derived therefrom. Specific examples include alkali metal salts of sulfoisophthalic acid such as 5-sodium sulfoisophthalic acid and 5-lithium sulfoisophthalic acid, 5- (tetraalkyl) phosphonium sulfoisophthalic acid and ester-forming derivatives derived therefrom. It is done.

  The polyester fiber structure of the present invention may be a filament yarn such as false twisted yarn, strong twisted yarn, taslan processed yarn, thick yarn, and mixed yarn in addition to a normal flat yarn. Examples thereof include fiber structures such as tows and spun yarns, and woven fabrics, knitted fabrics, nonwoven fabrics and spun yarns obtained therefrom, and woven fabrics, knitted fabrics, nonwoven fabrics and products obtained therefrom.

  The polyester fiber structure of the present invention can be formed into an alloy by bonding with other polymers such as polyamide at the time of spinning.

  Other fibers such as natural fibers, regenerated fibers, semi-synthetic fibers and synthetic fibers can be mixed in the polyester fiber structure of the present invention. As a composite form by mixing other fibers, any form such as mixed spinning, union weaving and union knitting can be used.

  Examples of natural fibers include cotton, kapok, hemp, flax, cannabis, hemp, wool, alpaca, cashmere, mohair and silk. Examples of the regenerated fiber include viscose, cupra, polynosic, high-wet modulus rayon, and solvent-spun cellulose fiber. Examples of semisynthetic fibers include fibers made of acetate, diacetate, triacetate, and the like. Examples of the synthetic fiber include fibers made of polyamide, acrylic, vinylon, polypropylene, polyurethane, polyvinyl chloride, polyethylene, promix, and the like.

  In the present invention, other fibers can be mixed with the polyester fiber by any method, but since the effect of the present invention is reduced when the mixing ratio of the polyester fiber is reduced, the mixing ratio of the polyester fiber is 30% by mass or more. It is preferable that it is 50 mass% or more.

  Examples of methods for imparting hydrolysis resistance to the polyester fiber structure of the present invention include treatment in a bath, dry heat treatment, and wet heat treatment.

  As the treatment in the bath, a method in which a polyester fiber structure is put into a treatment liquid containing a terminal blocking agent and the treatment liquid is circulated is preferably used.

  As the processing equipment in the bath, use equipment such as Wins dyeing machine, jigger dyeing machine, paddle dyeing machine, drum type dyeing machine, liquid dyeing machine, airflow dyeing machine, beam dyeing machine, cheese dyeing machine, and overmeyer. be able to.

  The treatment temperature in the bath is preferably 80 to 140 ° C, more preferably 110 ° C to 140 ° C. Further, the treatment time is preferably 10 to 120 minutes, more preferably 20 to 60 minutes.

  During the treatment in the bath, the end-capping agent adheres to the polyester fiber and exhausts and reacts with the polyester fiber surface layer. When the treatment time is short, exhaustion and reaction of the end capping agent to the fiber surface layer are not sufficient, and satisfactory hydrolysis resistance may not be obtained. In addition, if the processing time is too long, productivity may decrease.

  In such a method, after treatment in a bath, dehydration and drying are performed. The drying may be performed under conditions that allow moisture to dry, and the temperature is preferably 100 to 140 ° C. The heat treatment performed after drying is preferably performed at a temperature of 80 to 200 ° C. The treatment time is preferably 15 seconds to 8 minutes. The heat treatment is more preferably at a temperature of 130 to 190 ° C. for 30 seconds to 5 minutes.

  When a hydrophobic dye typified by a disperse dye is mixed in the treatment liquid, it can be dyed together with the end-capping treatment, and dehydration, drying, and heat treatment after treatment in the bath are performed in a normal dyeing process. The drying and finishing set conditions can be applied.

  As the heat treatment apparatus, a tenter, a short loop, a shrink surfer, a cylinder dryer, or the like that can uniformly apply heat to the fiber can be used.

  Examples of the dry heat treatment include a method in which a treatment liquid containing a terminal blocking agent is applied to a polyester fiber structure using an apparatus such as mangle, and then dried and heat treated.

  As an apparatus for applying a treatment liquid containing the processing agent of the present invention to a polyester fiber, an ordinary mangle is preferably used as the liquid application apparatus, but an apparatus capable of uniformly applying a liquid to the fiber is used. It can also be applied by a foam processing machine, a printing method, an inkjet method, a spray method, a coating method, or the like.

  As a drying and heat treatment apparatus, a tenter, a short loop, a shrink surfer, a cylinder dryer, or the like can be used, but an apparatus that can uniformly apply heat to a fiber can be used.

  In the present invention, the fiber structure is immersed in a treatment liquid containing a terminal blocking agent, and is uniformly squeezed, then dried and heat-treated. The drying temperature is preferably 80 ° C to 150 ° C. The treatment time is preferably 15 seconds to 5 minutes, more preferably 100 to 140 ° C. for 30 seconds to 3 minutes.

  It is preferable that the heat processing temperature after drying is 80-200 degreeC. The treatment time is preferably 15 seconds to 8 minutes, more preferably 130 to 190 ° C. for 30 seconds to 5 minutes. If the treatment temperature is low, the reaction may not be sufficient and satisfactory hydrolysis resistance may not be obtained. Moreover, when processing temperature is too high, polyester will melt | dissolve.

  Examples of the wet heat treatment include a method in which a treatment liquid containing an end-blocking agent is applied to a polyester fiber using an apparatus such as mangle and then wet-heat-treated.

  As the wet heat treatment apparatus, an ordinary pressure steamer, a high pressure steamer, or the like can be used, but an apparatus that can uniformly apply heat to the fibers can be used. In a preferred embodiment, the fiber structure is immersed in a treatment liquid containing a terminal blocking agent and squeezed uniformly, followed by a wet heat treatment at a temperature of 80 to 140 ° C. The treatment time is preferably 15 seconds to 10 minutes.

  A carbodiimide compound is preferably used as the terminal blocking agent. The carbodiimide compound may be a compound having at least one carbodiimide group. For example, a compound represented by the following general formula (I) is used.

Wherein R1 is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an allyl group, and an aralkyl group having 7 to 20 carbon atoms. Represents at least one group selected from the group consisting of:
Specific examples of the carbodiimide compound include N, N′-di-o-tolylcarbodiimide, N, N′-diphenylcarbodiimide, N, N′-dioctyldecylcarbodiimide, N, N′-di-2,6- Dimethylphenylcarbodiimide, N-tolyl-N′-cyclohexylcarbodiimide, N, N′-di-2,6-diisopropylphenylcarbodiimide, N, N′-di-2,6-di-tert.-butylphenylcarbodiimide, N , N′-di-p-nitrophenylcarbodiimide, N, N′-di-p-aminophenylcarbodiimide, N, N′-di-p-hydroxyphenylcarbodiimide, N, N′-di-cyclohexylcarbodiimide, N, N'-di-p-tolylcarbodiimide, p-phenylene-bis-di-o-tolylcarbodiimide, p-f Nylene-bis-dicyclohexylcarbodiimide, hexamethylene-bis-dicyclohexylcarbodiimide, ethylene-bis-diphenylcarbodiimide, N, N'-benzylcarbodiimide, N-octadecyl-N'-phenylcarbodiimide, N-benzyl-N'-phenylcarbodiimide, N-octadecyl-N'-tolylcarbodiimide, N-phenyl-N'-tolylcarbodiimide, N-benzyl-N'-tolylcarbodiimide, N, N'-di-o-ethylphenylcarbodiimide, N, N'-di- p-ethylphenylcarbodiimide, N, N'-di-o-isopropylphenylcarbodiimide, N, N'-di-p-isopropylphenylcarbodiimide, N, N'-di-o-isobutylphenylcarbodiimide, N, N'- The -P-isobutylphenylcarbodiimide, N, N'-di-2,6-diethylphenylcarbodiimide, N, N'-di-2-ethyl-6-isopropylphenylcarbodiimide, N, N'-di-2-isobutyl- 6-isopropylphenylcarbodiimide, N, N′-di-2,4,6-trimethylphenylcarbodiimide, N, N′-di-2,4,6-triisopropylphenylcarbodiimide, N, N′-di-2, Examples include 4,6-triisobutylphenyl carbodiimide and N, N′-diisopropylcarbodiimide.

  Further, one or more compounds are arbitrarily selected from these carbodiimide compounds to block the carboxyl end groups of the polyester.

  Further, industrially available carbodiimide compounds include N, N′-di-2,6-diisopropylphenylcarbodiimide (TIC), N, N′-dicyclohexylcarbodiimide (DCC), N, N′-diisopropyl. Carbodiimide (DIC) can also be preferably used.

  Further, industrially available carbodiimide compounds include N, N′-di-2,6-diisopropylphenylcarbodiimide (TIC), N, N′-dicyclohexylcarbodiimide (DCC), N, N′-diisopropyl. Carbodiimide (DIC) can also be preferably used. “Starabzol” I, “Starbzol” I LF, “Stabakuzol” P, and “Starbzol” P-100, which are sold under the trade name “Starbzol” (registered trademark) by Line Chemie Japan, are preferably exemplified. The

  As a method for exhausting the terminal blocking agent to the surface layer of the fiber structure, a method in which the polyester chain is swollen with a carrier agent and the terminal blocking agent is exhausted to the surface layer can be used.

  As the carrier agent, a mixture of a phthalimide compound and a benzoic acid compound is preferably used. Conventionally used trichlorobenzene, methylnaphthalene, and the like have strong odors and easily generate carrier spots, so there is concern about the odor and quality of the final product as the working environment deteriorates.

  The ratio of the terminal blocking agent to the carrier agent in the treatment liquid is preferably 20 parts by mass to 60 parts by mass of the carrier agent with respect to 100 parts by mass of the terminal blocking agent, and more preferably 40 to 60 parts by mass of the carrier agent. is there. If the amount of the carrier agent is small, the end-blocking agent adheres to the surface of the fiber structure, but the surface layer is not exhausted, and sufficient hydrolysis resistance may not be obtained. Further, when the amount of the carrier agent is increased, the end-capping agent is exhausted to the inside of the fiber and the efficiency may be deteriorated.

  In the present invention, the phthalimide compound is a compound having a phthalimide group, and as the phthalimide compound, an N-substituted phthalimide having an aliphatic or aromatic alkyl group in the N group of phthalimide is preferably used.

  Examples of the substituent include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, benzyl and naphthalate. From the viewpoint of residual amount in processed products, odor, safety and handling workability, methyl, N-phthalimide having a low molecular weight aliphatic alkyl group such as ethyl, propyl, isopropyl, butyl and isobutyl is more preferably used. Among these, N-butylphthalimide is preferably used because it is excellent in compatibility with the carbodiimide compound.

  A benzoic acid compound is a benzoic acid derivative, and a benzoic acid ester composed of benzoic acid and an aliphatic or aromatic alcohol is preferably used. Examples of benzoic acid esters include ethyl benzoate, methyl benzoate, propyl benzoate, butyl benzoate, benzyl benzoate and phenyl benzoate, etc., compatibility with carbodiimide compounds, swelling effect of polyester chain, etc. From this point, benzyl benzoate and phenyl benzoate are more preferably used. Among them, benzyl benzoate, which has a molecular weight close to that of TIC which is a terminal blocking agent and is available at low cost, is preferably used.

  The mixing ratio of the phthalimide compound and the benzoic acid compound is preferably 10 parts by mass to 50 parts by mass of the benzoic acid compound, more preferably 15 parts by mass to 40 parts by mass with respect to 50 parts by mass of the phthalimide compound. Further, 20 to 30 parts by mass of a benzoic acid compound is a more preferable embodiment. Further, two or more phthalimide compounds and two or more benzoic acid compounds can be used.

  In the treatment liquid, a surfactant is preferably used in addition to the end-blocking agent and the carrier agent. The addition amount of the surfactant is preferably 10 to 40 parts by mass, and more preferably 15 to 30 parts by mass with respect to 100 parts by mass of the carbodiimide compound. When the surfactant is small, the carbodiimide compound is not sufficiently emulsified and dispersed, and when the surfactant is large, the exhaustion rate of the carbodiimide compound may decrease.

  The amount of the terminal blocking agent used in the present invention can be determined according to the amount of terminal carboxyl groups of the target polyester fiber.

  The polyester fiber structure of the present invention is excellent in hydrolysis resistance, dress shirt, blouse, pants, skirt, polo shirt, T-shirt, training wear, coat, sweater, pajamas, school uniform, work clothes, lab coat, clean room wear , Yukata, underwear, lining, and interlining. In particular, it is preferably used for uniform applications such as medical care, nursing care, and foods that require autoclaving at a temperature of 120 ° C to 130 ° C.

  Next, the present invention will be described more specifically with reference to examples. The physical properties in the examples were measured as follows.

(Measurement of various physical properties)
(1) Terminal carboxyl group concentration (equivalent / 10 ³ kg):
A precisely weighed sample was dissolved in benzyl alcohol, and chloroform was added thereto, followed by titration with a 0.1 N potassium hydroxide benzyl alcohol solution.

(2) Decomposed yarn strength (cN):
Using Autograph manufactured by Shimadzu Corporation, ten pieces of tensile strength per level were measured for multifilaments obtained by breaking down the woven fabric, and the average value was taken as the broken yarn strength.

(3) Strong retention rate (%):
Using a Tomy autoclave (ES-315), keeping the top temperature of 130 ° C. for 40 hours was the autoclave treatment, and the ratio of the split yarn strength before and after the autoclave treatment of the following formula was used as the strength retention.
Strength retention (%) = (Strength after autoclave treatment) / (Strength before autoclave treatment) × 100.

(4) Depth profile measurement by time-of-flight secondary ion mass spectrometry (TOF-SIMS):
TOF. Using SIMS 5 (manufactured by ION-TOF), depth profile measurement was performed under the following conditions.
Secondary ion polarity: Negative / mass range (m / z): 0-200
・ Raster size: 50μm
・ Number of scans: 1scan / cycle
・ Number of pixels (1 side) 256 pixels
・ Measurement degree of vacuum (before sample introduction): 4 × 10 −7 Pa (4 × 10 −9 mbar) or less ・ Charge neutralization: Yes ・ Post acceleration: 10 kV
・ Pulse width: 200ns
・ Primary ion species: Bi ⁺
・ Primary ion acceleration voltage: 25 kV
・ Pulse width: 200ns
・ Bunching: None (High spatial resolution measurement)
・ Etching ion: Cs +
・ Etching ion acceleration voltage: 0.5 kV
Measurement was performed in the depth direction from the surface of the fiber to calculate CN- / C-intensity, and the CN- / C-intensity ratio was calculated by the following formula.
(CN− / C−intensity ratio) = (CN− / C−intensity at a depth of 5 nm) / (CN− / C−intensity at a depth of 1 nm).

(Preparation of end-capping agent 1)
35 parts by mass of bis (2,6-diisopropylphenyl) carbodiimide (Stavaxol I LF; Rhein Chemie Japan Co., Ltd.), 6 parts by mass of benzyl benzoate (Nacalai Tesque), 14 masses of N-butylphthalimide (Nacalai Tesque) The parts are mixed and heated to a temperature of 60 ° C. to dissolve uniformly, gradually added to 35.0 parts by mass of water at a temperature of 70 ° C. with stirring by a propeller-type stirrer, emulsified and dispersed, allowed to cool, and end-capped. Agent 1 was obtained.

Example 1
A taffeta was woven using a 167 dtex-48 filament polyethylene terephthalate (PET) drawn yarn, and scouring, drying and intermediate setting were performed according to a conventional method to obtain a PET fabric.

  The obtained PET fabric was immersed in a treatment solution using 8.6% owf of the end-blocking agent 1 as the solid content of the end-blocking agent and a bath ratio of 1:20 using a high-pressure dyeing tester. Using MINI-COLOR (infrared mini color (Teksam Giken)), processing in the bath was performed while circulating the treatment liquid at 130 ° C. for 30 minutes. After draining, washing with water and centrifugal dehydration were followed by drying in a pin tenter set to a temperature of 130 ° C. Further, dry heat setting was performed for 1 minute with a width in a pin tenter set to a temperature of 170 ° C. to obtain a processed fabric fabric of Example 1. The obtained processed fabric fabric was a processed fabric fabric excellent in hydrolysis resistance as shown in Table 1.

(Example 2)
The same treatment as in Example 1 was performed except that the treatment with UR · MINI-COLOR was performed at a temperature of 135 ° C. in Example 1, and the processed fabric fabric of Example 2 was obtained. The obtained processed fabric fabric was a processed fabric fabric excellent in hydrolysis resistance as shown in Table 1.

(Example 3)
In Example 1, the process same as Example 1 was performed except having performed the process by UR * MINI-COLOR at the temperature of 140 degreeC, and the processed fabric fabric of Example 3 was obtained. The obtained processed fabric fabric was a processed fabric fabric excellent in hydrolysis resistance as shown in Table 1.

Example 4
In Example 1, the process same as Example 1 was performed except the usage-amount of the terminal blocker 1 having been 5.8% owf, and the processed fabric fabric of Example 4 was obtained. The obtained processed fabric fabric was a processed fabric fabric excellent in hydrolysis resistance as shown in Table 1.

(Example 5)
In Example 1, the same treatment as in Example 1 was performed except that the amount of the end-blocking agent used was 14.3% owf, and the processed fabric fabric of Example 5 was obtained. The obtained processed fabric fabric was a processed fabric fabric excellent in hydrolysis resistance as shown in Table 1.

(Comparative Example 1)
In Example 1, the same process as Example 1 was performed except not performing a terminal blockage process. As shown in Table 1, the obtained processed fabric fabric was a processed fabric fabric having low hydrolysis resistance.

Claims (5)

  CN structure at a depth of 5 nm from the fiber surface in the depth profile measurement by time-of-flight secondary ion mass spectrometry (TOF-SIMS) A polyester-based fiber structure, wherein the ratio of CN- / C-intensity at a depth of 1 nm to-/ C-intensity is in the range of 3.0 to 6.0.   The polyester fiber structure according to claim 1, wherein the fiber structure made of polyester fiber is a fiber structure made of aromatic polyester fiber.   The polyester fiber structure according to claim 1 or 2, wherein the carboxyl group terminal is partially blocked with a carbodiimide compound. The polyester fiber structure according to claim 3, wherein the carbodiimide compound is a compound represented by the following general formula (I).

Wherein R1 is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an allyl group, and an aralkyl group having 7 to 20 carbon atoms. Represents at least one group selected from the group consisting of:   The carbodiimide compound is at least one compound selected from the group consisting of N, N'-di-2,6-diisopropylphenylcarbodiimide, N, N'-di-cyclohexylcarbodiimide and N, N'-diisopropylcarbodiimide. The polyester fiber structure according to claim 3 or 4, wherein: