JP3461988B2 - Moisture permeable waterproof base material - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a moisture-permeable and waterproof substrate.

[0002]

2. Description of the Related Art For example, fire-fighting clothing is required to have waterproofness so that discharged water does not enter into the clothing and moisture permeability capable of releasing perspiration due to exercise during fire fighting activities. Fire fighting clothing that uses wood as the inner material is known.
More specifically, as an inner material for firefighting clothing, a woven fabric using aromatic polyamide fiber and a polytetrafluoroethylene microporous membrane (hereinafter referred to as "PTFE membrane") are laminated and integrated, or an aromatic material. It is known that a hydroentangled nonwoven fabric using polyamide fibers and a PTFE membrane are laminated and integrated. However, the former inner material has a poor heat insulating property, and the latter inner material has a problem of fuzzing due to friction. Further, since all the inner materials easily absorb water, there is a problem that the weight increases during the fire extinguishing activity and the workability deteriorates.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and is excellent in heat insulation and abrasion resistance and hard to absorb water. Provided is a moisture-permeable and waterproof substrate which can be suitably used.

[0004]

The moisture-permeable waterproof substrate of the present invention is a laminate of a moisture-permeable waterproof membrane and an entangled nonwoven fabric containing fibrillated liquid crystal polyester fibers. This liquid crystal polyester fiber is difficult to absorb water, and because this liquid crystal polyester fiber has a fibrillated entangled non-woven fabric structure, it is a moisture-permeable waterproof base material with excellent heat insulation and abrasion resistance. is there.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid crystal polyester fiber used in the present invention is obtained by spinning a liquid crystal polyester resin and has low water absorption. In the present specification, the “liquid crystal polyester-based resin” refers to a polymer capable of forming an anisotropic melt phase. This type of polymer contains regular parallel arrangements in the molecular chains, is generally elongated, flat, and has high rigidity in the long axis direction of the molecule. The anisotropic molten phase can be confirmed by, for example, a usual polarization measurement method using a crossed polarizer.

The liquid crystal polyester resin used in the present invention is not particularly limited, but is selected from wholly aromatic polyester resins in which an aromatic diol, an aromatic dicarboxylic acid and an aromatic hydroxycarboxylic acid are used alone or in an appropriate combination. Preferably. Among the wholly aromatic polyester resins, a copolymer of p-hydroxybenzoic acid and 2-hydroxynaphthalene-6-carboxylic acid has an excellent balance of spinnability and heat resistance, and p-hydroxybenzoic acid and terephthalic acid are excellent. Since the copolymer of acid and 4,4′-dihydroxybiphenyl has excellent heat resistance, it can be suitably used for applications requiring heat resistance, for example, fire fighting clothing applications.

As the aromatic diol, aromatic dicarboxylic acid, and aromatic hydroxycarboxylic acid, for example, the following can be used. (1) Aromatic diol

[Chemical 1] (In the formula, R ¹ and R ² are each independently a hydrogen atom,
Halogen atom (for example, chlorine atom, bromine atom, iodine atom, fluorine atom), alkyl group (for example, having 1 to 4 carbon atoms)
Lower alkyl group), a phenyl group, or a phenyl group substituted with a halogen atom (eg, chlorine atom, bromine atom, iodine atom, fluorine atom) or an alkyl group (eg, a lower alkyl group having 1 to 4 carbon atoms). Is)

[Chemical 2] (In the formula, A _{-CH 2 -, - C (CH} 3) 2 -, or -S
O ₂ −)

[Chemical 3] (2) Aromatic dicarboxylic acid

[Chemical 4] (In the formula, R ³ is a hydrogen atom, a halogen atom (for example, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom) or an alkyl group (for example, a lower alkyl group having 1 to 4 carbon atoms).
Is)

[Chemical 5] (3) Aromatic hydroxycarboxylic acid

[Chemical 6] (In the formula, R ⁴ is a hydrogen atom, a halogen atom (for example, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom) or an alkyl group (for example, a lower alkyl group having 1 to 4 carbon atoms))

[Chemical 7]

When spinning a liquid crystal polyester resin, even if a substituent is introduced into the aromatic ring, a non-linear monomer is used, or a bent chain is introduced in order to improve spinnability. good.

The liquid crystal polyester fiber obtained by spinning such a liquid crystal polyester resin can be improved in heat resistance by heat treatment at a temperature lower by about 50 ° C. than the melting point of the liquid crystal polyester resin. However, if heat treatment is applied for a long time, it will be difficult to fibrillate,
It is preferable not to perform heat treatment for a long time. It is preferable to use liquid crystal polyester fibers that have not been heat-treated at all after spinning.

The fibrillation of the liquid crystal polyester fiber may be carried out at the fiber stage, after the fiber web is formed, or after the nonwoven fabric is formed. Among these, if fibrillated at the fiber stage, when forming the fiber web, the liquid crystal polyester fibers are easily entangled, and it is difficult to form a homogeneous web of fiber, so after forming the fiber web, Alternatively, it is preferable that the nonwoven fabric is formed and then fibrillated.
As will be described later, by applying a water stream or a needle to the fiber web, the fiber web can be entangled at the same time,
This is a suitable fibrillation method because a nonwoven fabric excellent in mechanical strength, abrasion resistance, and heat insulation can be formed in one step. Hereinafter, a method of forming a fibrous web and then fibrillating the fibrous web will be described.

The liquid crystalline polyester fiber is preferably used in an amount of 5% by weight or more, more preferably in a non-woven fabric so that the mechanical strength, abrasion resistance, and heat insulation due to the formation of fine pores in the fibrillated fiber are improved. Is 10% by weight or more, and most preferably 20% by weight or more. Fibers that can be used in addition to the liquid crystal polyester fiber vary depending on the application, but for example, when used as an inner material for fire fighting clothing that requires heat resistance, acrylic oxide fiber,
It is preferable to use rayon-based oxidized fibers, carbon fibers, glass fibers, meta- or para-type aramid fibers, polyamideimide fibers, aromatic polyetheramide fibers, polybenzimidazole fibers, novoloid fibers, polybenzbisoxazole fibers, and the like.

As these fibers, fibers having a fineness of about 0.1 to 10 denier can be used. However, use of fibers having a small fineness is preferable because a nonwoven fabric having finer pores can be formed and the heat insulating property is excellent. is there. The fiber length differs depending on the method of forming the fiber web. For example, the wet method is about 1 to 25 mm, and the dry method is 20 mm.
Use about 110 mm.

As a method for forming a fiber web using these fibers, there are, for example, a wet method, a dry method such as a card method and an air lay method, and a direct method such as a spun bond method and a melt blow method. Among them, the dry method is easier to form a bulky fibrous web than the wet method, and as a result, a nonwoven fabric having excellent heat insulating properties is easily formed. Therefore, in the case where it is more suitable for use as having excellent heat insulating properties, for example, for use as an inner material for fire fighting clothes, it is preferable to form the fiber web by a dry method.
Further, when forming a fibrous web by the card method, a unidirectional fibrous web formed by a card machine and a fibrous web crossed by a cross layer or the like are included to make a nonwoven fabric strong in the transverse direction as well. Therefore, the fiber orientation is suitable.

Then, the liquid crystal polyester fibers contained in the fiber web are fibrillated and entangled,
A non-woven fabric having excellent abrasion resistance and heat insulation is formed. As the fibrillation and entanglement means, for example,
There is a method of applying water flow or needle, and if it is the former method of applying water flow, it will act evenly on the entire fibrous web to form a more uniform fibril and form a denser and more homogeneous nonwoven fabric. Therefore, it is more preferable. The conditions for applying this water flow are, for example, a nozzle diameter of 0.05 to 0.3 mm, preferably 0.08 to 0.2 mm, a nozzle pitch of 0.2 to 3 mm, and preferably 0.4 to 2 mm. Nozzle plates arranged in one or more than two rows are used and pressure is 10
A water stream of up to 300 kg / cm ² , preferably 50 to 250 kg / cm ² may be jetted. This action by the water flow is performed once or twice or more, and is applied to one side or both sides of the fibrous web. In addition,
When using a thick net with a non-opening portion of less than 50 mesh as a support such as a net for transporting the fibrous web when it is acted on by a water stream, a non-woven fabric with large pores can be formed, and a non-opening portion of 50 mesh or more can be formed. If a fine hole is used, it is possible to form a non-woven fabric having no apparent holes.

In the present invention, as described above,
As the liquid crystal polyester fiber, it is preferable to use one that has not been heat treated for a long time after spinning. Therefore, when more heat resistance is required, after fibrillating the liquid crystal polyester fiber, the liquid crystal polyester resin is used. It is preferable to perform the heat treatment at a temperature about 50 ° C. lower than the melting point of

The non-woven fabric of the present invention thus obtained is excellent in mechanical strength and abrasion resistance. For example, only fibrillated liquid crystal polyester fiber (1
A non-woven fabric having a basis weight of 50 g / m ² in which a fibrous web composed of 100%) is entangled by a water flow has a tear strength of 1 kgf or more and an abrasion resistance of grade 3 or more. This tear strength is JIS-
L-1096-6.15.1 (A-1 method, single tongue method) is the value measured by the method specified, and wear resistance is evaluated by the method specified by JIS-L-1076, A method. Say.

The moisture-permeable waterproof material of the present invention has moisture-permeable and waterproof properties obtained by laminating and integrating a moisture-permeable waterproof film on the above-mentioned nonwoven fabric. As the moisture-permeable and waterproof film, for example, a PTFE film, a urethane film, a neoprene rubber film, or the like can be used, but when heat resistance is required as in firefighting clothes, the PTFE film can be preferably used. When laminating and integrating this PTFE membrane with non-woven fabric,
It is preferable to partially adhere with an adhesive so as not to impair the microporosity of the E film. When laminating and integrating with the urethane film, a urethane resin is wet-coated on the nonwoven fabric or the urethane film is an adhesive. It is preferable to partially adhere with.

As described above, since the moisture-permeable waterproof base material of the present invention has moisture-permeable waterproof property, the weight of external water does not increase, and the internal vapor can be discharged, and the thermal insulation and abrasion resistance can be improved. It has excellent workability and does not easily absorb water, so it has excellent workability.
In addition, when a PTFE membrane having excellent heat resistance is used as the moisture-permeable waterproof membrane, it is a base material that can be suitably used as an inner material for fire fighting clothing. When using this moisture-permeable and waterproof base material as an inner material for firefighting clothes, the non-woven fabric is arranged so as to contact the outer material, and the PTFE membrane is arranged so as to contact the knit or non-woven fabric which is the heat insulating layer. To use,
Since the entangled nonwoven fabric of the moisture-permeable waterproof substrate of the present invention has excellent abrasion resistance, it can be used for a long period of time without fluffing.

Examples of the present invention will be described below, but the invention is not limited to the following examples.

[0020]

【Example】

(Example 1) It is made of a copolymer of p-hydroxybenzoic acid and 2-hydroxynaphthalene-6-carboxylic acid, is not heat-treated after spinning, is easily fibrillated, has a fineness of 2.5 denier, and a fiber length. A unidirectional fiber web formed by opening 100% of 51 mm liquid crystal polyester fiber (Vectran NT, manufactured by Kuraray Co., Ltd.) by a card machine, and a unidirectional fiber web similarly formed by opening. And a crossed fiber web crossed in the flow direction of the fiber web with a cross layer at a weight ratio of 4: 1 to form a laminated fiber web. This laminated fiber web 8
Placed on a 0 mesh support and placed on a unidirectional fiber web, nozzle diameter 0.13 mm, nozzle pitch 0.6
After ejecting a water flow from a nozzle plate of mm at a pressure of 50 kg / cm ^2, it is reversed and a pressure of 80 kg is applied from the same nozzle plate.
/ cm ² jets a water stream, further reverses it, jets a water stream from the same nozzle plate at a pressure of 50 kg / cm ² , fibrillates the liquid crystal polyester fibers and simultaneously entangles them, with a basis weight of 50 g / m ² , A non-woven fabric having a thickness of 0.19 mm was formed. Next, a fluorine-based dispersion adhesive is sprinkled on this nonwoven fabric, and then a PTFE membrane (registered trademark: Microtex, manufactured by Nitto Denko Corporation) is laminated and dried to form the nonwoven fabric and PTF.
The E membrane was integrated to form the moisture-permeable waterproof substrate of the present invention.

Comparative Example 1 p-hydroxybenzoic acid and 2
A liquid crystal polyester fiber (Bectran HT, Kuraray Co., Ltd.) made of a copolymer with -hydroxynaphthalene-6-carboxylic acid, which was heat treated for a long time after spinning, did not fibrillate, had a fineness of 2.5 denier and a fiber length of 51 mm. ))
A nonwoven fabric having a basis weight of 50 g / m ² and a thickness of 0.19 mm was formed in the same manner as in Example 1 except that 100% was used. Then, in the same manner as in Example 1, the non-woven fabric and the PTFE membrane were integrated to form a moisture-permeable waterproof substrate. When the nonwoven fabric was observed with an electron microscope, the liquid crystal polyester fiber was not fibrillated.

Example 2 The same liquid crystal polyester fiber as in Example 1 was used in an amount of 10% by weight, a fineness of 2 denier and a fiber length of 51.
mm meta type aramid fiber (Conex, Teijin Ltd.)
The liquid crystal polyester fiber was fibrillated in the same manner as in Example 1 except that 90% by weight was mixed with each other to form a nonwoven fabric having a basis weight of 100 g / m ² and a thickness of 0.90 mm. Then, in the same manner as in Example 1, the non-woven fabric and PTF are used.
The E membrane was integrated to form a moisture-permeable waterproof substrate.

Comparative Example 2 A non-woven fabric having a basis weight of 100 g / m ² and a thickness of 1.0 mm was formed in the same manner as in Example 1, except that the same meta-aramid fiber as in Example 2 was used in 100%. did. Then, in the same manner as in Example 1, the non-woven fabric and PT
The FE membrane was integrated to form a moisture-permeable waterproof substrate.

(Comparative Example 3) A plain woven fabric using the same meta-aramid fiber as in Example 2 (woven density: warp yarn = 55 yarns / 2
5 mm, weft = 55 threads / 25 mm, basis weight 64 g / m ² , thickness 0.19 mm) were used instead of the non-woven fabric in the same manner as in Example 1 to integrate the plain weave and the PTFE membrane,
A moisture-permeable waterproof substrate was formed.

(Abrasion resistance test) The abrasion resistance of the non-woven fabrics or fabrics of Examples 1 and 2 and Comparative Examples 1 to 3 was measured according to JIS-L-1.
076, evaluated by the method defined in Method A. The results are shown in Table 1.

[0026]

[Table 1]

(Tear Strength Test) The tear strength of the nonwoven fabrics or woven fabrics of Examples 1 and 2 and Comparative Examples 1 to 3 was measured according to JIS-L-1.
096-6.15.1 (A-1 method, single tongue method). The results are also shown in Table 1.

(Water Absorption Test) After the moisture-permeable and waterproof substrates of Examples 1 and 2 and Comparative Examples 1 to 3 were cut into 10 cm squares, the moisture-permeable and waterproof substrates were each kept at a temperature of 20 ° C. and a humidity of 65. % (W1) was measured by leaving it in a constant temperature and temperature chamber apparatus for 24 hours. Then, the moisture-permeable waterproof substrate was left in a thermo-hygrostat at a temperature of 40 ° C. and a humidity of 90% for 1 hour to obtain a weight (W2).
Was measured and the rate of increase was calculated by the formula of (W2-W1) / W1 to evaluate the water absorption of the moisture-permeable waterproof substrate. The results are also shown in Table 1.

(Adiabatic Test) From the moisture-permeable waterproof membrane side of the moisture-permeable waterproof substrates of Examples 1 and 2 and Comparative Examples 1 to 3, a heat quantity of 0.05 cal / cm ² · sec was applied by an electric heater. The heat insulating property of the moisture-permeable and waterproof substrate was evaluated from the temperature rise on the back surface when irradiated with. The results are also shown in Table 1.

[0030]

The moisture-permeable waterproof substrate of the present invention is a laminate of a moisture-permeable waterproof film and an entangled nonwoven fabric containing fibrillated liquid crystal polyester fibers. The liquid crystal polyester fiber is difficult to absorb water and has a fibrillated entangled non-woven fabric structure, and thus is excellent in heat insulation and abrasion resistance.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields investigated (Int.Cl. ⁷ , DB name) D04H 1/00-18/00 B32B 1/00-35/00

Claims (4)

(57) [Claims] 1. A moisture-permeable, waterproof substrate comprising a moisture-permeable and waterproof film and an entangled nonwoven fabric containing fibrillated liquid crystal polyester fibers which are laminated and integrated. 2. The moisture-permeable waterproof substrate according to claim 1, wherein the moisture-permeable waterproof membrane is a polytetrafluoroethylene microporous membrane. 3. The liquid crystal polyester fiber is characterized by comprising a copolymer of p-hydroxybenzoic acid and 2-hydroxynaphthalene-6-carboxylic acid.
Alternatively, the moisture-permeable and waterproof substrate according to claim 2. 4. The moisture permeable and waterproof substrate according to claim 1, wherein the entangled nonwoven fabric is entangled by a water flow.