JPH11189976A - Water repellent/antistatic synthetic fiber structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a synthetic fiber structure having high water repellency, high water resistance, more excellent antistatic properties, and washing durability as for the water repellency, water resistance and antistatic properties. SOLUTION: This water repellent/antistatic synthetic fiber structure is obtained by treating a fiber structure consisting essentially of a synthetic fiber with a water repellent, especially a water repellent composed of a (meth)acrylate polymer containing a fluoroalkyl group at the side chain, an anionic antistatic agent, especially an alkyl phosphoric ester-based antistatic agent and a crosslinking agent, especially a block isocyanate compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-repellent and antistatic synthetic fiber structure, and more particularly to a water-repellent and water-repellent material having high washing durability and water repellency and suitable for medical materials and sanitary materials.・
The present invention relates to an antistatic synthetic fiber structure.

[0002]

2. Description of the Related Art Synthetic fiber structures such as woven fabrics and nonwoven fabrics made of synthetic fibers are generally apt to be charged with static electricity because the constituent fibers are hydrophobic. Among them, a synthetic fiber structure made of polyolefin fibers is made of non-polar polyolefin, and thus is particularly easily charged with static electricity. As a method for solving such a drawback of the synthetic fiber, a method using an antistatic agent is generally used. However, when the antistatic agent is applied to the surface of the synthetic fiber structure or kneaded into the constituent fibers, the antistatic property is improved, but on the other hand, due to the hydrophilic effect of the antistatic agent, the inherent repellency is possessed. May lose water.

Therefore, as a method of imparting antistatic properties without reducing water repellency, a fluorine resin water repellent exhibiting high water repellency is used in combination with an anionic antistatic agent or a cationic antistatic agent. Then, a method for treating a synthetic fiber structure such as a polyolefin nonwoven sheet has been proposed (Japanese Patent Application Laid-Open No. 4-289270, Japanese Patent Application Laid-Open No. 63-594).
No. 79). Fluororesin-based water repellents are generally weak cationic, so when used in combination with a cationic antistatic agent,
Shows high antistatic properties with a small amount without adverse effects due to ionic differences with fluororesin-based water repellents. However, on the other hand,
Since the hydrophilicity is also increased, it is difficult to balance water repellency and antistatic properties, and there is a drawback that there is no washing durability and the antistatic properties are lost in high-temperature treatment. In addition, cationic antistatic agents have relatively high toxicity and are not desirable from the viewpoint of safety depending on the use. On the other hand, although the anionic antistatic agent has low toxicity, it is inappropriate to be used in combination with the fluororesin water repellent from the viewpoint of ionicity, and the washing durability is imparted with a high water repellent antistatic property.
Have difficulty. Therefore, in recent years, as a water-repellent antistatic formulation having high washing durability, a three-component surface treatment formulation in which an additive such as a crosslinking agent is further added to a two-component system of a fluororesin water repellent and an antistatic agent has been added. For example, there has been proposed a method of using a fluorine resin-based water repellent, a quaternary ammonium salt and a blocked isocyanate in combination to carry out antistatic and water-repellent treatment of a synthetic fiber structure ( JP-A-6-316869). However, in this method, the water resistance is insufficient because the cationic antistatic agent used is too hydrophilic.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a water-repellent, water-resistant, and antistatic laundry which has high water repellency and high water resistance, and further has excellent antistatic properties. An object of the present invention is to provide a synthetic fiber structure having excellent durability.

[0005]

Means for Solving the Problems In order to solve the above problems, the present invention provides a method of treating a fibrous structure composed mainly of synthetic fibers with a water repellent, an anionic antistatic agent, and a crosslinking agent. And a water-repellent and antistatic synthetic fiber structure.

Further, the present invention provides the above-mentioned water-repellent / antistatic synthetic fiber structure, wherein the water-repellent agent comprises a (meth) acrylate polymer having a fluoroalkyl group in a side chain. is there.

The present invention also provides a water-repellent / antistatic synthetic fiber structure wherein the crosslinking agent is a blocked isocyanate compound.

The present invention also provides a water-repellent and antistatic synthetic fiber structure wherein the anionic antistatic agent is an alkyl phosphate ester antistatic agent.

Further, the present invention provides a synthetic fiber structure wherein the fiber structure is a polyolefin nonwoven fabric.

Further, the present invention provides a synthetic fiber structure wherein the polyolefin nonwoven fabric is made of at least one selected from a spunbonded nonwoven fabric and a meltblown nonwoven fabric.

Hereinafter, the synthetic fiber structure of the present invention (hereinafter referred to as “the synthetic fiber structure”)
The “structure of the present invention” will be described in detail.

The structure of the present invention is obtained by treating a fiber structure mainly composed of synthetic fibers with a water repellent, an antistatic agent and a cross-linking agent. Examples of the method include a method using a mixed treatment agent. The main material of the structure of the present invention is a synthetic fiber, and may be a synthetic fiber composed of one kind of synthetic resin, a composite fiber composed of two or more kinds of synthetic resins having different physical properties, or may contain other materials. , Is not particularly limited. Examples of the fiber structure include a woven fabric and a nonwoven fabric. Examples of the synthetic resin that is the material of the synthetic fiber constituting the fiber structure include, for example, polyethylene, polypropylene, polybutene, and polyolefins such as block or random copolymers of other α-olefins, polyesters, polyamides, and the like. Can be Among these, a nonwoven fabric made of a polyolefin is preferable in terms of high economic efficiency and the high effect of the treatment. Examples of the conjugate fiber include a conjugate fiber having a core-sheath structure or a side-by-side structure having a portion made of polyethylene and a portion made of polypropylene. Further, this fiber structure may contain other components in addition to the synthetic fibers made of polyolefin or the like, for example, may contain natural fibers, inorganic fibers, etc. Material, an inorganic filler, and the like.

The nonwoven fabric used as the fibrous structure is not particularly limited, and examples thereof include spunbonded nonwoven fabrics, meltblown nonwoven fabrics, and laminated nonwoven fabrics obtained by laminating a plurality of these nonwoven fabrics. Specific examples of the laminated nonwoven fabric include those having a structure laminated in the order of spun bond / melt blow / spun bond. Also,
Each nonwoven fabric constituting the laminated nonwoven fabric may be made of different materials or may be made of the same material. As a spunbond nonwoven fabric, the average fiber diameter of the constituent fibers is 5 to 5.
Those having a thickness of 50 μm are preferred, and those having a thickness of 10 to 30 μm are particularly preferred. Further, the weight is preferably 5 to 100 g / m ² , particularly preferably 10 to 50 g / m ² , from the viewpoint that the balance between the strength and the texture (softness) is good. Further, as the melt blown nonwoven fabric, those having an average fiber diameter of the constituent fibers of 0.1 to 10 μm are preferable, and in particular,
Thicknesses of 1 to 5 μm are preferred. In terms balance of water resistance and breathability is good, preferably has a basis weight of 1 to 100 g / m ^2, particularly preferably from 5 to 50 g / m ^2.

In the present invention, the water repellent, which is a component of the mixed treatment agent used for treating the fibrous structure, is preferably composed of a (meth) acrylate polymer having a fluoroalkyl group in a side chain. Examples of the (meth) acrylate polymer having a fluoroalkyl group in a side chain include, for example,
A polymer of a fluorine-containing (meth) acrylate derivative represented by the following formula (1), a polymer of a fluorine-containing (meth) acrylate derivative represented by the following formula (1),
A mixture with a polymer of a (meth) acrylate derivative represented by the following formula (2), or a fluorine-containing (meth) acrylate derivative represented by the following formula (1):
Examples include a copolymer with a (meth) acrylate derivative represented by the following formula (2).

Embedded image

In the above formula (1) or (2), R ¹
Is a hydrogen atom or a methyl group, and R ² has 3 to 3 carbon atoms.
21 is a fluoroalkyl group, and R ³ has ³ to 2 carbon atoms.
1 alkyl group. Examples of the fluoroalkyl group having 3 to 21 carbon atoms of R ² include a group represented by the following formula (2-a) or (2-b).

Embedded image In the formula (2-a), m is an integer of 2 to 20. In the formula (2-b), k is an integer of 1 to 5, and n is an integer of 1 to 19.

Among these polymers and copolymers,
In that it is easy to form a coating on the fiber surface, the orientation of the fluoroalkyl group can be aligned, and the water repellency of the fluoroalkyl group can be sufficiently exhibited.
As R ³ , those containing a (meth) acrylate derivative having an n-butyl group, an iso-butyl group, a hexyl group, an n-octyl group, a decyl group, a dodecyl group, a stearyl group and the like are preferable.

Further, (meth) a used as a water repellent
In the acrylate polymer, the (meth) acrylate polymer is
The total number of alkyl groups N (R¹+ R^Two+ R^Three)
The number of fluoroalkyl groups N (R^Two) Ratio N
(R^Two) / N (R¹+ R^Two+ R ^Three) Is from 30 to
Preferably it is 100%, especially 40-80%
Some are preferred. This range of fluoroalkyl groups
Having a (meth) acrylic acid polymer
Is a treatment liquid used for the treatment of nonwoven fabric which is a fiber structure
Good dispersibility in the inside. Also, out of the range,
If the proportion of fluoroalkyl groups is too low,
D) A water repellent composed of an acrylate polymer has sufficient repellency.
Water effect does not appear, on the other hand, beyond the above range, fluoro
If the proportion of alkyl groups is too high, the water repellent will
Coating on the surface of non-woven fabric fibers
May be difficult to form.

In the present invention, examples of the anionic antistatic agent used for treating the fiber structure include sulfonate salts such as alkyl sulfonates, alkylbenzene sulfonates, alkyl naphthalene sulfonates, and alkyl diphenyl sulfonates. Examples include antistatic agents, phosphorus-containing antistatic agents such as alkyl phosphates, alkyl phosphites, alkyl phosphonic acids, and alkyl phosphonates. Among these, phosphorus-containing antistatic agents are preferable in that good water resistance is obtained and toxicity is low, and alkyl phosphate antistatic agents are particularly preferable.
Examples of the alkyl phosphate ester antistatic agent include the following formula (3):

Embedded image Can be mentioned. In the formula (3), a plurality of R ⁴ may be the same or different and are a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or Na, K, or NH ₄ .

Preferred examples of the alkyl phosphate ester antistatic agent include the following formula (3-a):

Embedded image The compound represented by these is mentioned. In the formula (3-a), at least one of R ⁵ is an n-butyl group, an n-hexyl group, an n-octyl group, or a decyl group, and the others are the same as the above R ⁴ .

In the present invention, the crosslinking agent used for treating the fiber structure is a polyfunctional blocked isocyanate compound,
It is a methylol compound, a guanidine derivative, or the like, which has an effect of forming a strong surface treatment film. Among them, in terms of excellent washing durability even at low temperature treatment,
Blocked isocyanate compounds are preferred. Examples of the blocked isocyanate compound include aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate, aliphatic diisocyanates such as hexamethylene diisocyanate, and alicyclic diisocyanates such as isophorone diisocyanate. A typical example is a product obtained by reacting an isocyanate with a blocking agent such as a phenol-based, lactam-based, active methylene-based, or oxime-based to protect the isocyanate group of the isocyanate.

Specific examples of the blocked isocyanate compound include those obtained by blocking the isocyanate group of tolylene diisocyanate with a phenolic blocking agent, those obtained by blocking the isocyanate group of tolylene diisocyanate with diethyl malonate, and those obtained by blocking the isocyanate group of tolylene diisocyanate. And those blocked with methyl ethyl ketoxime.

When the treatment of the fibrous structure is carried out with a mixture of three components, the effective solid content of each component of the water repellent, antistatic agent and cross-linking agent in the treatment is 0.5%. To 30% by weight, preferably 1.0 to 8.0% by weight, and the antistatic agent is 0.5 to 10% by weight, preferably 0.1 to 5.0% by weight.
And the cross-linking agent is 0.05 to 10% by weight, preferably 0.1 to 5.0% by weight.

In addition to the water repellent, the antistatic agent and the cross-linking agent, various additives may be added to the mixed treating agent as required. For example, when using a blocked isocyanate compound as a crosslinking agent, polyamines, amines such as amidoamine, dibutyltin thiolate, dibutyltin stearate, organic metal salts such as zinc stearylate, and the like, dissociation of the blocking agent of the blocked isocyanate compound The blocking agent that dissociates usually at about 150 ° C. is dissociated at a low temperature of about 100 to 130 ° C. to regenerate the isocyanate group. The regenerated isocyanate group reacts with active hydrogen such as an OH group of the antistatic agent to form a crosslink, and can be treated at a low temperature, so that the surface of the constituent fibers of the nonwoven fabric, which is a fibrous structure, is not impaired. This has the advantage that a strong water-repellent / antistatic film having high durability can be formed.

For the purpose of improving abrasion resistance of physical properties such as antistatic property and water repellency of the structure of the present invention, a guanidine salt derivative such as guanidine dicarboxylate may be appropriately added.

The preparation of the mixed treatment agent is carried out by dissolving the water repellent, the antistatic agent and the crosslinking agent, and various additives to be added as required, in a predetermined amount in a solvent. it can. The solvent is not particularly limited, and water is usually used. In particular, ketones such as acetone and methyl ethyl ketone, or alcohols such as ethanol and iso-propanol, in that dispersibility of each component in the mixing agent is improved, and furthermore, treatment such as application to a fiber structure is facilitated. May be added as appropriate.

In the production of the structure of the present invention, the fiber structure is treated with the mixed treating agent, and the surface of the fiber structure is coated with a treatment liquid of 1 to 50 g / m ² , preferably 3 to 30 g / m ² . ^Two
Can be carried out in such a manner as to adhere with an adhesion amount of If the amount of the treatment liquid is too small, sufficient antistatic performance may not be obtained.On the other hand, if the amount of the treatment liquid is too large, high antistatic performance can be obtained, but on the other hand, hydrophilicity is poor. And the water repellency may not be sufficient. Examples of the coating method include a dipping method, a gravure roll method, a spray method, and a roll coating method. The fiber structure treated with the mixed treatment agent is dried and heat-treated by hot air heating or a hot drum to obtain the structure of the present invention.

[0027]

EXAMPLES The present invention will be described below more specifically based on examples of the present invention and comparative examples. In addition, the melting point of the following nonwoven fabric materials, MFR, the basis weight of the nonwoven fabric, antistatic properties (charge potential, half-life), surface resistivity, water repellency, water resistance,
The measurement or evaluation of the washing durability was performed according to the following method.

Melting point: Determined using a DSC (differential scanning calorimeter). Melt flow rate (MFR): ASTM D1238
Temperature: 230 ° C, load: 2.16 kgf
(21.18N). Basis weight: Performed according to the method described in JIS L 1906. Charge voltage and half-life: A described in JIS L 1094
Performed according to law. Surface specific resistance: Performed according to JIS K 6911. Water repellency: by spraying method described in JIS L 1092. Water resistance: Water resistance test A described in JIS L 1092
According to the hydrostatic method. Washing test: washing three times under the conditions described in JIS L 0217 103, antistatic properties before and after washing,
The water repellency and the water resistance were measured and used as indices for washing durability.

(Example 1) Spunbonded nonwoven fabric made of polypropylene having an MFR of 35 g / 10 min and a melting point of 160 ° C, and an MFR of
A nonwoven fabric laminate having a basis weight of 50 g / m ² (hereinafter referred to as “SMS”) is formed by laminating a meltblown nonwoven fabric made of polypropylene having a melting point of 159 ° C. and 700 g / 10 min in the order of spunbond / meltblown / spunbond. "
) On both surfaces by a gravure roll method, 5.0 g / m ² of a mixed treatment solution having the following composition, for a total of 10 g / m ^2.
After the application, drying and heat treatment were performed for 30 seconds in a 130 ° C. hot air heater to obtain a surface-treated nonwoven fabric. Composition of mixed treatment liquid: Water repellent and blocked isocyanate mixed liquid 30% by weight (Toho Chemical Industry Co., Ltd., Lipperan FX-9700H, active ingredient amount: 25% by weight) Water repellent component (having a fluoroalkyl group in a side chain) About 15% by weight Block isocyanate compound component About 10% by weight Alkyl phosphate ester antistatic agent 4% by weight (manufactured by Toho Chemical Industry Co., Ltd., Anstex AK-25, active ingredient amount: 50% by weight) 66% by weight of solvent (water)

The antistatic properties (charge potential, half-life), surface resistivity, water repellency, water resistance, and washing durability of the obtained surface-treated nonwoven fabric were measured or evaluated. Table 1 shows the results.

Comparative Example 1 A surface-treated nonwoven fabric was obtained in the same manner as in Example 1 except that an antistatic agent composed of a cationic quaternary ammonium salt was used instead of the alkyl phosphate ester antistatic agent. The antistatic properties (charge potential, half-life), surface resistivity, water repellency, water resistance, and washing durability were measured or evaluated. Table 1 shows the results.

(Comparative Example 2) A surface-treated nonwoven fabric was obtained in the same manner as in Example 1 except that no blocked isocyanate was used, and its antistatic properties (charge potential, half-life), surface resistivity, water repellency, and water resistance were obtained. The degree and washing durability were measured or evaluated. Table 1 shows the results.

Comparative Example 3 The SMS nonwoven fabric used in Example 1 was subjected to antistatic properties (charge potential, half-life), surface resistivity, water repellency, water resistance, and washing without surface treatment. The durability was measured or evaluated. Table 1 shows the results.

[0034]

[Table 1]

According to Table 1, the surface-treated nonwoven fabric of Example 1 which is the synthetic fiber structure of the present invention has higher water resistance than the surface nonwoven fabric obtained in Comparative Example 1, and is obtained in Comparative Example 2. The antistatic property is higher in washing durability and water resistance than the surface-treated nonwoven fabric, and the antistatic performance is significantly improved while maintaining water repellency and water resistance as compared with the SMS nonwoven fabric of Comparative Example 3. You can see that.

[0036]

Industrial Applicability The synthetic fiber structure of the present invention has high water repellency and high water resistance, and also has excellent antistatic properties, as well as its water repellency, water resistance and antistatic washing durability. It is excellent. Therefore, the synthetic fiber structure of the present invention is expected to be expanded for various uses. In particular, those made of non-woven fabric as the fiber structure, surgical gowns,
Medical materials such as OFF (cloth), sheets, CSR wrap (sterile wrap), shoe covers, caps, isolation gowns, aprons, etc., sanitary materials such as disposable diapers, various protective clothing, industrial materials such as packaging materials, Packaging materials such as furoshiki,
It is suitable as a storage material such as a laundry bag and a material for household materials such as an apron.

Claims (5)

[Claims] 1. A water-repellent / antistatic synthetic fiber structure obtained by treating a fiber structure mainly composed of synthetic fibers with a water-repellent agent, an anionic antistatic agent and a crosslinking agent. 2. The water-repellent and antistatic synthetic fiber structure according to claim 1, wherein the water-repellent agent comprises a (meth) acrylate polymer having a fluoroalkyl group in a side chain. 3. The water-repellent and antistatic synthetic fiber structure according to claim 1, wherein the crosslinking agent is a blocked isocyanate compound. 4. The water-repellent and antistatic synthetic fiber structure according to claim 1, wherein the anionic antistatic agent is an alkyl phosphate ester antistatic agent. 5. The water-repellent / antistatic synthetic fiber structure according to claim 1, wherein the fiber structure is a polyolefin nonwoven fabric.