JPS6250596B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing polyester fibers having special micropores and durable antibacterial properties. Polyester fiber has many excellent properties, but its use in medical institutions such as hospitals, socks,
As the development of applications such as underwear progresses, there is an increasing need to develop clothing materials that have antibacterial and antibacterial effects against bacteria and mold. The present invention is a method for obtaining durable antibacterial polyester fibers by forming fine pores on the surface of polyester fibers and applying an antibacterial compound mainly to these pores. Conventionally, as a method of imparting uneven pores to the surface of polyester fibers, fibers made of polyoxyethylene glycol or polyester blended with polyoxyethylene glycol and a sulfonic acid compound are treated with an alkaline aqueous solution to form wrinkles arranged in the fiber axis direction. A method for producing hygroscopic fibers in which micropores are formed on the surface of the fibers, or polyester fibers prepared by adding fine particles of an inert inorganic substance such as zinc oxide, calcium phosphate, etc. to a polyester reaction system are treated with an alkaline aqueous solution. A method for producing hygroscopic fibers has been proposed in which fine pores are formed by eluting inorganic fine particles. however,
The fibers obtained by these methods have too large pores, making them unsuitable for improving the durability of antibacterial agents, and they also easily fibrillate, resulting in a whitish appearance. It had The inventor of the present invention formed micropores on the surface of polyester fibers, and as a result of conducting intensive studies to mainly add an antibacterial agent to the pores, the inventor blended a specific low-molecular compound with high compatibility with polyester. The present invention was achieved based on the discovery that uneven micropores can be formed on the fiber surface by alkali treatment of polyester fiber obtained by melt spinning from a polyester composition prepared by the present invention. That is, in the present invention, 0.1 to 0.1 to 100 parts by weight of a low molecular weight compound satisfying the following conditions (1) to (4) is added to 100 parts by weight of aromatic polyester.
A polyester composition containing 30 parts by weight is melt-spun, the resulting polyester fibers are treated with an aqueous solution of an alkaline compound to elute 2% by weight or more of the fibers, and then a finishing agent with antibacterial properties is added. This is a method for producing antibacterial polyester fibers. (A) Substantially stable under the melting conditions of the aromatic polyester, non-reactive with the polyester, and compatible with the polyester. (B) Phase separation does not occur with the polyester composition when the polyester composition is cooled and solidified. (C) Melting point is 100℃ or higher. (D) The molecular weight is 1000 or less. The aromatic polyester used in the present invention is
The main acid component is aromatic dicarboxylic acid, and the aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenyl ether dicarboxylic acid, and diphenol dicarboxylic acid. Examples include siethanedicarboxylic acid, methyl terephthalic acid, and methyl isophthalic acid. In addition, glycol components include ethylene glycol,
Aliphatic glycols such as trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, etc.
Alicyclic glycols such as 1,4-cyclohexanedimethanol, hydroquinone, methylhydroquinone, butylhydroquinone, amylhydroquinone, resorcinol, 2,2-bis(4-
hydroxyphenyl) propane [bisphenol A], 1,1-bis(4-hydroxyphenyl)
Cyclohexane [busphenol Z], bis(4
-hydroxyphenyl) ether and the like can be used. In addition to the above-mentioned dicarboxylic acid component and glycol component, an oxycarboxylic acid component may be used, and examples of the oxycarboxylic acid include oxybenzoic acid, oxynaphthoic acid, and β-hydroxyethoxybenzoic acid. In addition to the above components, the aromatic polyester used in the present invention contains a small proportion (usually 10 mol% or less of the total acid components) of aliphatic dicarboxylic acids such as adipic acid and sebacic acid, and hexahydroterephthalic acid. It may contain alicyclic dicarboxylic acids such as and 5-sodium sulfoisophthalic acid, and a small amount (usually 10% by weight or less) of polyoxyalkylene glycol may be copolymerized. Furthermore, within the range where the aromatic polyester is substantially linear (usually 1 mol% or less), trimellitic acid,
A polycarboxylic acid such as pyromellitic acid, a polyol such as glycerin, trimethylolpropane, pentaerythritol, etc. may be copolymerized. Among the above aromatic polyesters, the following general formula (m represents an integer of 2 to 6) A polyester mainly having repeating units represented by the following is preferable, and among them, polyethylene terephthalate and polybutylene terephthalate are particularly preferable. Such aromatic polyester may be synthesized by any method. For example, in the case of polyethylene terephthalate, usually terephthalic acid and ethylene glycol are directly esterified, a lower alkyl ester of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol, or terephthalic acid and ethylene glycol are transesterified. a first step reaction of producing a glycol ester of terephthalic acid and/or a low polymer thereof by reacting with an oxide;
It is produced by a second stage reaction in which the reaction product of the first stage is heated under reduced pressure to perform a polycondensation reaction until a desired degree of polymerization is achieved. Next, the low molecular weight compound to be added to the aromatic polyester will be explained. In the present invention, the low molecular weight compound to be blended into the aromatic polyester is (1) substantially stable and non-reactive with the aromatic polyester under the melting conditions of the aromatic polyester, for example at a temperature of +20° C. to the melting point of the polyester; In addition, it is necessary that when blended with the aromatic polyester, it does not cause phase separation and is uniformly compatible with the aromatic polyester. Here, “substantially stable,
"Non-reactive with aromatic polyesters" means that it does not decompose itself, does not decompose aromatic polyesters, or does not react with aromatic polyesters. ) Even when the homogeneous melt obtained by melt-mixing the aromatic polyester and the low-molecular compound is cooled and solidified, the aromatic polyester and the low-molecular-weight compound do not undergo phase separation and remain uniformly compatible. It is necessary that the
For example, when the above-mentioned homogeneous transparent melt is cooled at a cooling rate sufficient to give an amorphous solid, a homogeneous transparent solid is obtained, or phase separation occurs to give an opaque solid. This can be easily determined by looking at the Furthermore, low molecular weight compounds (3) have a melting point of 100℃ or higher,
and (4) the molecular weight must be 1000 or less. If the melting point of the low molecular weight compound is 100℃ or less,
When melt-mixed with an aromatic polyester, it significantly lowers the secondary transition point of the aromatic polyester, making it difficult to handle during molding. The low-molecular compound used in the present invention may be one that satisfies the above conditions (1) to (4), but in addition, from the viewpoint of preventing volatilization during melt-mixing, the low-molecular compound has a boiling point at normal pressure.
A temperature of 250°C or higher, particularly 300°C or higher is preferably used. The low molecular weight compound used in the method of the present invention may be one that satisfies the above conditions, but for example, the following formula () [Here, A ¹ is a divalent aromatic residue or a chain or cyclic aliphatic residue, which may be substituted; R ¹ is an n-valent aromatic residue or a chain or cyclic aliphatic residue. Cyclic aliphatic residues, which may be substituted; n is 1 or 2. However, the imide ring in the above formula is 5 or 6 members. ] Imide compound represented by the following formula () [Here, A ² is a tetravalent aromatic residue, which may be substituted; R ² is a monovalent chain or cyclic aliphatic residue, which may be substituted. Good too. However, the imide rings in the above formula are 5- or 6-membered. Examples include imide compounds represented by the following. As a compound of the above formula (), the above formula ()
Compounds in which at least one of A ¹ or R ¹ is an optionally substituted aromatic residue, particularly compounds in which A ¹ is a divalent optionally substituted aromatic residue are preferred. used. Further, as the compound of the above formula (), a compound in which R ² is one optionally substituted aliphatic residue in the above formula () is preferably used. In the above general formula (), examples of the divalent aromatic residue representing A ¹ include a 1,2-phenylene group, a 1,2-, 2,3-, or a 1,8-naphthylene group. Examples of divalent aliphatic residues include linear alkylene groups such as ethylene or trimethylene, and cycloalkylene groups such as 1,2-cyclohexylene. These groups may be substituted with a substituent that is non-reactive with the aromatic polyester (A). Examples of such substituents include lower alkyl groups such as methyl and ethyl, lower alkoxy groups such as methoxy and ethoxy, halogen atoms such as chlorine and bromine, nitro groups, phenyl groups, phenoxy groups, and methyl groups. Good examples include cyclohexyl. The n-valent (n=1 or 2) aromatic residue representing R ¹ is, for example, a phenyl group, a naphthyl group, or a

A monovalent aromatic residue such as a group of the formula [where Z is -O-, -SO ₂ - or -CH ₂ -], or a 1,2-phenylene group, 1,2-, 2・3- or 1,8-naphthylene group or formula

Mention may be made of divalent aromatic residues such as the group [formula] (where Z is -O-, -SO ₂ - or -CH ₂ -),
As n-valent (n=1 or 2) aliphatic residues,
For example, a linear alkyl group having 1 to 18 carbon atoms such as methyl, ethyl, butyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, myricityl, stearyl, or a 5- or 6-membered cyclic alkyl group such as cyclohexyl or cyclopentyl, or a linear alkylene group having 2 to 12 carbon atoms such as ethylene, trimethylene, tetramethylene, hexamethylene, octamethylene, decamethylene, dodecamethylene; a cyclic alkylene group such as a 1,3- or 1,4-cyclohexylene group;

Examples include groups such as [Formula]. These groups representing R ¹ may be substituted with the same substituents as described for A ¹ . In the above formula (), the tetravalent aromatic residue representing A ² is, for example,

【formula】

【formula】

【formula】

[Formula] or

Preferred examples include monocyclic, condensed ring, or polycyclic tetravalent aromatic groups represented by the formula: (Z is the same as defined above). The monovalent chain or cyclic aliphatic residue representing R ² may be a chain alkyl group having 1 to 18 carbon atoms or a 5- or 6-membered cyclic alkyl group as exemplified for R ¹ in the above formula (). Mention may be made of alkyl groups. The groups exemplified above for A ² and R ² may be substituted with the same substituents as described for A ¹ . Examples of the imide compound represented by the above formula () include N-methyl phthalimide, N-ethyl phthalimide, N-butylphthalimide,
N-ethyl-1,8-phthalimide, N-butyl-1,8-naphthalimide, etc.; as compounds when n=2, N・N'-ethylenebisphthalimide, N・N'-tetramethylenebisphthal imide, N/N'-hexamethylene bisphthalimide, N/N'-octamethylene bisphthalimide, N/N'-decamethylene bisphthalimide, N/N'-dodecamethylene bisphthalimide, N・N′-neopentylene bisphthalimide, N・N′-tetramethylene bis(1,8-
naphthalimide), N・N′-hexamethylenebis(1,8-naphthalimide), N・N′-octamethylenebis(1,8-naphthalimide),
N・N'-decamethylene bis(1,8-naphthalimide), N・N'-dodecamethylene bis(1,8-naphthalimide),
8-naphthalimide), N・N′-dodecamethylene bissuccinimide, N・N′-dodecamethylene bishexahydrophthalimide, N・N′-
1,4-cyclohexylene bisphthalimide,
1-phthalimido-3-phthalimidomethyl-3,5,5-trimethylcyclohexane, 4.
4′-bisphthalimido diphenyl ether,
3,4'-bisphthalimido diphenyl ether, 3,3'-bisphthalimido diphenyl sulfone, 4,4'-bisphthalimido diphenyl sulfone, 4,4'-bisphthalimido diphenyl Examples include methane. Examples of the imide compound represented by the above formula () include N.N'-diethylpyromellitimide, N.N'-dibutylpyromellitimide,
N・N'-dihexylpyromellitimide, N・
N′-dioctylpyromellituimide, N・N′-
Didecylpyromellituimide, N・N'-dicyclohexylpyromellituimide, N・N'-bis(3,3,5-trimethylcyclohexyl)pyromellituimide, N・N'-diethyl-1,4.
5,8-naphthalenetetracarboxylic acid 1,8-,
Examples include 4,5-diimide. The imide compounds represented by the above formulas () and () can be easily produced from the corresponding acid anhydrides and organic amines by known methods. In the present invention, first, aromatic polyester
A polyester composition is obtained by blending 0.1 to 30 parts by weight of a low molecular compound with 100 parts by weight. If the amount of the low-molecular compound is less than 0.1 parts by weight, the amount of micropores in the final polyester fiber obtained will be insufficient, and as this amount is increased, the amount of micropores will increase, but it is less than 30 parts by weight. If it exceeds this amount, no significant improvement is shown, and the abrasion resistance and durability deteriorate on the contrary, and the melt viscosity of the resulting composition decreases significantly, making melt spinning difficult. The blending amount of the low molecular weight compound is more preferably 3 to 20 parts by weight. A composition consisting of an aromatic polyester and a low-molecular compound may be prepared by adding the low-molecular compound and the polyester to a raw material or a reaction mixture at any stage until the synthesis of the polyester is completed, for example, during the synthesis of the polyester after mixing. It may be a finished product, or it may be a simple dry blend of polyester chips and a low-molecular compound, or it may be a product that has been melt-mixed in a melt extruder in advance. It is also preferable that the low-molecular compound obtained by heating and melting the low-molecular compound above the melting point is mixed with the aromatic polyester chip and then cooling to below the melting point, and the low-molecular compound obtained is attached to the surface of the aromatic polyester chip. used. The above composition may contain optional additives such as catalysts, oxidation stabilizers, ultraviolet stabilizers, flame retardants, fluorescent whitening agents, matting agents, colorants, etc. as necessary. In addition, from the viewpoint of increasing the degree of polymerization or suppressing a decrease in the degree of polymerization during melt spinning, 2.
A chain extender such as 2'-(bis(2-oxazoline), 2,2'-bis(3,1-benzoxazin-4-one), etc.) can be preferably blended into the polyester thus obtained. There is no need to adopt a special method to melt-spun the composition into fibers, and a normal melt-spinning method for polyester fibers can be arbitrarily adopted.The fibers spun here have hollow parts. The fiber may be a solid fiber with no hollow part or a hollow fiber with a hollow part.In addition, the outer shape and the shape of the hollow part in the cross section of the fiber to be spun may be circular or irregular. In order to remove a part of the polyester fiber obtained in this way and make it into a porous polyester fiber, the polyester fiber is subjected to stretching heat treatment or false twisting as necessary, or after being made into a fabric, an aqueous solution of an alkali compound is added. The alkaline compounds used here include sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, sodium carbonate, potassium carbonate, etc. Among them, water Sodium oxide and potassium hydroxide are particularly preferred.The concentration of the aqueous solution of such an alkali compound varies depending on the type of alkali compound, treatment conditions, etc., but is usually preferably in the range of 0.01 to 40% by weight, particularly
A range of 0.1 to 30% by weight is preferred. The processing temperature is preferably in the range of room temperature to 100°C, and the processing time is 1 minute to 1 minute.
It is usually carried out for a period of 4 hours. Further, the amount of the alkali compound eluted and removed by treatment with the aqueous solution should be in the range of 2% by weight or more based on the weight of the fiber. By treating with an aqueous solution of an alkali compound in this manner, a large number of special micropores can be formed on the fiber surface and in its vicinity. Note that the polyester fiber obtained by the method of the present invention can be treated with an organic solvent as necessary to extract and remove low-molecular compounds remaining in the fiber. Examples of such organic solvents include toluene, xylene, pseudocumene, dioxane, chloroform, methylene chloride,
Examples include dichloroethane, ethanol, ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, and chlorobenzene.
These organic solvents are preferably selected appropriately depending on the type of aromatic polyester and low molecular weight compound, especially imide compound. Although this extraction treatment using an organic solvent can be carried out at room temperature, it is preferable to carry out heating within a range that does not impair the morphology and physical properties of the polyester fiber, for example, under reflux conditions of the organic solvent. After micropores are formed on the surface of the polyester fiber in this manner, a finishing agent having antibacterial properties is applied thereto. The antibacterial processing agent used in the present invention refers to various molds such as black mold, blue mold, Aspergillus aspergillus, spider mold, tinea interdigitum, etc., and bacteria such as Escherichia coli, Pseudomonas aureus, Staphylococcus aureus, Bacillus subtilis, and diphtheriae. It refers to a compound that has excellent antibacterial and bactericidal effects against bacteria such as Salmonella typhi and Salmonella swine fever. Specifically, organic metal compounds such as cutupanaphthanate, tinku dimethyl-dithiocarbamate, and trimethyltin acetate, and organic compounds such as pentachlorophenol, 2-chloro-orthophenylphenol, orthochlorobenzole derivatives, and tetrachloroparabenzoquinone A compound is used. Particularly effective are quaternary ammonium compounds, such as cetyltrimethylammonium bromide, cetylpyridinium chloride, methyldodecyltrimethylammonium chloride, and organosilicone quaternary ammonium salts represented by the following formula are particularly effective. (n = integer from 16 to 20) This product is, for example, 09 manufactured by Dow Corning Co., Ltd.
It is commercially available under the trade name -5700. The appropriate amount of these processing agents to be applied to the polyester fiber having uneven micropores is 0.1% by weight or more and 5% by weight or less. The method of applying the antibacterial finishing agent to the fibers in the present invention may be any conventionally known method, such as immersion method (adsorption in liquid),
Patting methods, spraying methods, coating methods, etc. can be used as appropriate. It is best to apply the processing agent at a stage close to the final product, and after the porous treatment,
It is particularly effective to carry out the dyeing and then apply the dye. It can also be used in combination with general finishing agents such as hard finishing agents, antistatic agents, and water and oil repellent agents. Hereinafter, the present invention will be specifically explained with reference to Examples. Examples 1 to 6 100 parts of polyethylene terephthalate chips with an intrinsic viscosity of 0.645 and a softening point of 260°C were dry-blended with a predetermined amount of the low molecular weight compound shown in Table 1, and then the resulting mixture was passed through a circular spinning hole with a pore diameter of 0.3 mm. Melt-spun at 275℃ using a spinneret with 36 holes,
Then, it was stretched at a stretching ratio of 4.5 times according to a conventional method to 75
A raw yarn of denier/36 filament was obtained. This yarn has S twist of 2500T/m and Z twist of 2500T/m.
Then, the highly twisted yarn was heat-treated at 80° C. for 30 minutes to fix the twist. The twisted yarn has a warp density of 47 threads/cm and a weft density of 32.
A pear-skinned jersey fabric was woven by alternately arranging two S and Z fibers at a fiber/cm ratio. The obtained gray fabric was relaxed with a rotary washer for 20 minutes at boiling temperature, then grained, preset using a conventional method, and then treated with a 3.5% sodium hydroxide aqueous solution at boiling temperature to achieve a weight loss rate of 10. % fabric was obtained. After dyeing this fabric using a conventional method, the following formula is applied. In an aqueous solution of organosilicon quaternary ammonium salt with a concentration of 0.5% by weight (relative to fiber weight) and a bath ratio of 1:50, the compound was immersed for 30 minutes at 80°C to exhaust the compound, then dehydrated and dried. did. In addition, the antibacterial test method in the examples uses Bacillus subtilis as a representative of fission bacteria and Trichophyton as a representative of mold, and the inhibition diameter (average distance from the specimen periphery) and bacteria on the cloth surface are measured using the plate method. Occurrence status (- means no occurrence, +
(occurred). Washing durability was evaluated by washing in a home washing machine in a 40°C washing liquid containing 1 g of neutral detergent. No washing is defined as L ₀ , and continuous washing for 100 minutes is defined as L 0.
L _{is 10} , and when rinsing continuously for 300 minutes, L is ₃₀ . Comparative Example 1 is the result of carrying out the same treatment in a system without the addition of a low molecular compound. It is clear from Table 1 that a durable antibacterial finishing effect can be obtained by the present invention.

【table】

Claims (1)

[Claims] 1. The following conditions (A) are added to 100 parts by weight of aromatic polyester.
A polyester composition containing 0.1 to 30 parts by weight of a low-molecular compound that satisfies ~(D) is melt-spun, and the resulting polyester fibers are treated with an aqueous solution of an alkaline compound to elute 2% by weight or more of the fibers. 1. A method for producing antibacterial polyester fibers, which comprises applying a finishing agent having antibacterial properties after drying. (A) Substantially stable under the melting conditions of the aromatic polyester, non-reactive with the polyester, and compatible with the polyester. (B) No phase separation occurs from the polyester when the polyester composition is cooled and solidified. (C) Melting point is 100℃ or higher. (D) The molecular weight is 1000 or less. 2 Aromatic polyester has the following general formula (m represents an integer of 2 to 6) The method for producing a polyester fiber according to claim 1, wherein the polyester fiber is mainly composed of repeating units represented by the following. 3. The method according to claim 1, wherein the compound having antibacterial properties is a quaternary ammonium compound. 4. The method according to claim 3, wherein the quaternary ammonium compound is an organosilicone quaternary ammonium salt represented by the following formula. (n = integer from 16 to 20)