JP4692229B2 - Laminated sheet - Google Patents

Description

  The present invention relates to a laminated sheet reinforced with glass fibers and the like. More specifically, when used as an asphalt-containing waterproofing material base fabric, it is excellent in integrity and dimensional stability with an impregnating agent such as asphalt, and is excellent in low cost. The present invention relates to a laminated sheet that exhibits excellent waterproof properties.

  Conventionally, asphalt waterproofing has been excellent in waterproofing and durability in the construction method in the construction field, and since the effect is stably obtained, it is highly reliable, and also easy to work and economical. Widely used because of its advantages. As the asphalt waterproofing base fabric used in the asphalt waterproofing construction method, polyester nonwoven fabrics are often used from the viewpoint of balance between physical properties and high economic efficiency. There has been a problem that wrinkles are generated or breakage occurs due to insufficient strength, and water leaks from the broken part. In order to solve such a problem, an asphalt waterproof base fabric in which glass fibers are combined with a polyester nonwoven fabric has recently been used, and a resin impregnation treatment and a thermocompression treatment have been proposed as a method for integrating the layers (for example, Patent Document 1). reference)

  However, the resin-impregnated laminated sheet is hard to feel, so defects such as wrinkles are likely to occur, the asphalt impregnation property is further lowered, and it is not preferable from an economical viewpoint.

  In addition, lamination by thermocompression treatment requires strong thermocompression bonding to be firmly integrated, and is likely to be paper-like, which is not satisfactory from the performance and economic viewpoints as with resin impregnation treatment. .

In addition, a laminating method using only needle punches not impregnated with resin is also conceivable, but the entanglement integrity with the reinforcing fiber is weak compared to the resin processed product, etc., and it is difficult to obtain the reinforcing effect of the reinforcing fiber, the initial stress is low, and the dimensions Since it becomes a laminated body inferior in stability, a problem occurs in use under high temperature atmosphere conditions in asphalt impregnation processing, and it has not been widely adopted.
JP-A-7-52299

  The present invention has been made against the background of the prior art, and is suitable for use as a base fabric for waterproofing materials, etc., which has no excessive increase in cost, is excellent in impregnation with an impregnating agent such as asphalt, and is excellent in workability. An object of the present invention is to provide a laminated sheet.

As a result of intensive studies to solve the above problems, the present inventors have finally completed the present invention. That is, the present invention provides (1) a reinforcing fiber between a nonwoven fabric (nonwoven fabric A) having a stress at 5% elongation of 40 N / 5 cm or more and a nonwoven fabric (nonwoven fabric B) having a stress at 5% elongation of 5 N / 5 cm to 30 N / 5 cm. Is laminated and laminated by the mechanical entanglement method, (2) The lamination according to (1), wherein the mechanical entanglement method is a needle punching method or a water punching method (3) The laminated sheet according to (2), wherein the nonwoven fabric B is disposed on the needle penetration inlet side or the water punch water inlet side in needle punching, (4) 5% elongation after lamination The time stress is 60 N / 5 cm or more, characterized in that it is a laminated sheet in any one of (1) to (3), and (5) the nonwoven fabric A and / or the nonwoven fabric B is a nonwoven fabric bonded by thermocompression. (1 ~ (4) laminated sheet according to any one, (6) the a basis weight of 20 ~ 60 g / m ² nonwoven A, is equal to or less than 80% the basis weight of the nonwoven fabric B (1) (5) The laminated sheet according to any one of the above, (7) the fineness of the fibers constituting the nonwoven fabric A is 1 to 4 dtex, and the temperature is 40 to 10 ° C. lower than the melting point of the resins constituting the nonwoven fabric A and the nonwoven fabric B. The laminated sheet according to any one of (1) to (6), which is strongly pressure-bonded by a roll.

  According to the present invention, a reinforcing sheet excellent in dimensional stability can be obtained without applying a resin impregnation process, and it becomes difficult to form a width when impregnating asphalt, and a waterproof material and a heat insulating material without excessive increase in cost. Further, it is possible to provide a laminated sheet useful as a base fabric such as a soundproof material, an insulating material, and a reinforcing material.

Hereinafter, the present invention will be described in detail.
As a result of earnest research on the method of laminating to be strongly integrated with the reinforcing fiber by the mechanical entanglement method that does not impair the flexibility and asphalt impregnation property, the inventors of the present application shared the role to be played by the nonwoven fabric of each layer, By laminating a non-woven fabric (nonwoven fabric A) that contributes to improving the initial elongation stress and dimensional stability of the laminated sheet and a non-woven fabric (nonwoven fabric B) that mainly contributes to strengthening the integrity of the laminated sheet, it is possible to reinforce even the mechanical entanglement method. The present inventors have found that a laminated sheet having a high initial elongation stress and excellent dimensional stability can be obtained because the lamination integrity with the fiber can be reinforced.

That is, the laminated sheet of the present invention is between a nonwoven fabric (nonwoven fabric A) having a stress at 5% elongation of 40 N / 5 cm or more and a nonwoven fabric (nonwoven fabric B) having a stress at 5% elongation of 5 N / 5 cm to 30 N / 5 cm. It is preferable that the reinforcing fibers are arranged and laminated by a mechanical entanglement method.

By setting the nonwoven fabric A to 40 N / 5 cm or more, a laminated sheet having excellent initial elongation stress characteristics and dimensional stability can be obtained even by the mechanical entanglement method. Although the upper limit is not particularly problematic, even if it exceeds 150 N / 5 cm, a particularly excellent effect is not obtained, and since it is generally densified, impregnation properties such as asphalt are reduced. More preferably, it is 45-120 N / 5cm, More preferably, it is 50-100 N / 5cm.

Since the nonwoven fabric B can be strongly laminated and integrated with the reinforcing fiber by a mechanical entanglement method when the stress at 5% elongation is 5 N / 5 cm to 30 N / 5 cm, the potential of the reinforcing fiber is added to the laminated sheet. It can be exhibited effectively. That is, according to the flexible nonwoven fabric B, the fibers of the nonwoven fabric B are easily transferred to the nonwoven fabric A by mechanical entanglement treatment, and can be entangled strongly. A more preferable range is 7 to 25 N / 5 cm, still more preferably 10 to 20 N / 5 cm.

The laminated sheet of the present invention may be laminated by a needle punching method or a water punching method. This is because such a method can be laminated without impairing impregnation properties such as flexibility and asphalt. Needless to say, the laminated sheet of the present invention is within the scope of the present invention even if the integrity is further enhanced by some thermocompression bonding or the like.

The laminated sheet of the present invention is preferably arranged on the needle penetration inlet side when the nonwoven fabric B is laminated and integrated by needle punching, and on the water punch water inlet side when laminated and integrated by water punching. This is because the fibers of the non-woven fabric B easily enter the non-woven fabric A during the mechanical entanglement process, the integrity is enhanced, and the effect of inserting the reinforcing fibers between the non-woven fabrics can be further extracted.

The laminated sheet of the present invention preferably has a stress at 5% elongation after lamination of 60 N / 5 cm or more. This is because, if it has a 5% elongation stress exceeding 60 N / 5 cm, practically satisfactory dimensional stability can be obtained when used as an asphalt waterproofing material base fabric. The upper limit is not particularly provided, but even if it exceeds 150 N / 5 cm, it is not particularly useful in practice, and problems such as increased costs are likely to occur. A more preferable range is 65 to 100 N / 5 cm, still more preferably 80 to 90 N / 5 cm.

The laminated sheet of the present invention is preferably a nonwoven fabric obtained by thermocompression bonding the nonwoven fabric A and / or the nonwoven fabric B. This is because thermocompression bonding makes it easy to control the stress at 5% elongation of each nonwoven fabric, suppresses fluff and the like, and reduces the cause of troubles in the subsequent process.

The nonwoven fabric B used in the laminated sheet of the present invention is appropriately selected depending on the required properties, but when used as an asphalt-containing waterproofing material, it is preferably ²⁰ to 200 g / m ² from the viewpoint of handleability and performance, particularly performance, 30 to 150 g / m ² is preferable from the viewpoint of product weight and cost.

The nonwoven fabric A used for the laminated sheet of the present invention has a basis weight of 10 to 80 g / m ² and is preferably 80% or less with respect to the basis weight of the nonwoven fabric B. This is because the nonwoven fabric A reinforces the dimensional stability in the entire laminate as described above, and also plays a role of connecting the nonwoven fabric B and the glass fiber. More preferably, it is 20-60 g / m < ² >.

The fineness of the nonwoven fabric A used for the laminated sheet of the present invention is preferably 1 to 4 dtex. If it is this range, it is because the nonwoven fabric with high dimensional stability and the stress at the time of 5% expansion | extension is obtained, and it can demonstrate the effect which said nonwoven fabric A bears. More preferably, it is 2-3 dtex.

It is preferable that the nonwoven fabric A used for the laminated sheet of the present invention is superheated and pressure bonded. This is because the nonwoven fabric A plays the role of a reinforcing cloth in the laminated sheet of the present invention, and can impart performance as a reinforcing cloth by strong pressure bonding. Here, in order to perform strong pressure bonding, for example, a needle embossing roll and a flat calender roll, a temperature lower by 40 ° C. to 10 ° C. than the melting point of the nonwoven fabric, more preferably a temperature of 20 ° C. to 10 ° C., and a roll linear pressure of 30 to 30 ° C. 60 kN / m, more preferably, the linear pressure can be 40 to 60 kN / m.

Here, in the case of a low linear pressure, the inter-fiber adhesion is insufficient and the strength and elongation are difficult to improve. Further, in the case of high linear pressure, the performance as a reinforcing sheet is satisfied, but when the sheet is formed into a film and subjected to needle punching, the needle penetration resistance is increased, and there is a tendency that needle breakage and productivity decrease are caused. Further, this processing step is performed after the web is formed and before needle punch lamination. After the reinforcing fibers are laminated, there is a problem that the initial stress of the base fabric obtained by cutting the reinforcing fibers by roll processing at high pressure and high temperature is lowered.

  The nonwoven fabric used for the laminated sheet of the present invention is not particularly limited, but is preferably a long fiber nonwoven fabric. This is because by using a long fiber nonwoven fabric, it can be applied in applications requiring high strength such as asphalt impregnation.

  As a long-fiber nonwoven fabric, you may form by the well-known span bond system and the melt blow system, for example.

  As a short fiber nonwoven fabric, a well-known needle punch nonwoven fabric, a thermocompression bonding nonwoven fabric, a binder processing nonwoven fabric, etc. can be used, and it is not specifically limited.

  Non-woven fabric material is not particularly limited, natural fibers such as cotton, wool and silk, semi-synthetic fibers such as rayon, synthetic fibers such as polyester, polyamide, polyolefin, PVA and vinylon, high strength polyethylene fibers, aramid fibers, etc. High modulus fibers, and the like. Polyester fibers are preferred from the viewpoint of ease of production, balance between performance and cost, utilization of recycled materials, and the like.

  Examples of such polyester fibers include polyethylene terephthalate, polybutylene terephthalate, and the like, as well as copolymer polyesters of copolymerization components such as isophthalic acid, adipic acid, diethylene glycol, trimethylene glycol, and polytetramethylene glycol, polyethylene naphthalate, and these. Copolymers can also be used.

  When the nonwoven fabric is a synthetic fiber, it is usually melt-spun to form a web, but if necessary, an openability improving agent at the melt-spinning stage and an antioxidant at the spinning or web-forming stage, Stabilizers, ultraviolet absorbers, flame retardants and the like can be added.

  When the nonwoven fabric is not a synthetic fiber or is not thermoplastic, a known hot melt type binder fiber such as polyester, polyamide, or polyethylene can be mixed.

The reinforcing fiber inserted between the two layers of the nonwoven fabric may be either a multifilament or a monofilament, and a known glass fiber can be used.
The fineness of the glass fiber is usually about 30 to 75 tex, and the wire diameter is preferably 0.5 mm or less. When the fineness of the glass fiber is increased, the fiber is likely to be raised on the surface and unevenness is likely to occur, and when the fineness is decreased, it is difficult to obtain the desired initial strength (stress).

  The plurality of glass fibers in the present invention are preferably inserted at predetermined intervals in parallel to the longitudinal direction of the nonwoven fabric, and the insertion pitch is preferably 1 to 30 mm. A more preferable insertion pitch is 3 to 10 mm. If the insertion pitch is increased, unevenness is likely to occur on the surface due to shrinkage of the nonwoven fabric after impregnation with asphalt or the like. On the other hand, if the insertion pitch is reduced, there is no major problem in physical properties, but the amount of fiber used increases and it is uneconomical.

When the laminated sheets of the present invention are laminated and integrated by needle punching, the needle insertion density is preferably 20 to 120 / cm ² . When the needle density is less than 20 / cm ² , the confounding property is poor and the lamination effect is difficult to be exhibited. When the needle density exceeds 120 / cm ² , the unevenness of the surface of the laminated nonwoven fabric becomes large, or the glass fiber breaks. It tends to happen.

  The glass fiber reinforced laminated nonwoven fabric of the present invention is a thermosetting material such as a waterproofing agent such as asphalt, an epoxy resin, and an unsaturated polyester resin as various base fabrics such as a waterproofing material, a heat insulating material, a soundproofing material, an insulating material, and a reinforcing material. It is impregnated or laminated with a thermoplastic resin such as resin, polyvinyl alcohol resin and polyurethane resin, and used for various purposes.

  Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to these examples. In addition, the evaluation method of the physical property value described in the present invention is as follows.

[5% elongation stress and tensile strength of laminated nonwoven fabric] (N / 5 cm): laminated nonwoven fabric using a constant speed stretch type tensile tester (Orientec Tensilon) according to the cut strip method described in JIS L-1096 The average value of 5% elongation stress and tensile strength obtained by measuring the product width of 50 mm from the width of 50 mm and the length of 200 mm of the sample piece at a gripping interval of 100 mm and a tensile speed of 200 mm / min. / 5 cm) and tensile strength (N / 5 cm).

[Nonwoven fabric fineness] (dtex): Set to an optical microscope equipped with a digital microscopic eyepiece so that the cut surface of a sample sampled from an arbitrary part of the nonwoven fabric can be observed. For 50 arbitrary fibers cut at right angles, the lengths of the major axis and minor axis of the fiber cross section are measured, the cross sectional area of each fiber is obtained, and the cross section of the fiber is calculated by averaging these values. Separately, the fiber density was obtained and applied, and the weight at a length of 10,000 m was calculated.

Example 1
Polyethylene terephthalate having a melting point of 260 ° C and an intrinsic viscosity of 0.63 is discharged from the spinning nozzle at a melting temperature of 285 ° C using a spinning nozzle with a caliber of 0.30 mm, single hole discharge rate of 1.5 g / min / hole, and 300 holes. The fiber was collected on a metal net and made into a web after being pulled and thinned by an ejector at a spinning speed of 4500 m / min, cooled and taken up. This web was weakly pressure-bonded with a thermocompression-bonding roll to obtain a nonwoven fabric (nonwoven fabric B) on the needle penetration entrance side in needle punching. The basis weight of the obtained nonwoven fabric was 70 g / m ² . The stress at 5% elongation was 15 N / 5 cm. The speed of the fiber repair net was increased, and the temperature of the thermocompression-bonding roll was set to 250 ° C. and the linear pressure was set to 50 kN / m to make a nonwoven fabric as a reinforcing sheet. The basis weight of the obtained nonwoven fabric was 40 g / m ² , and the stress at 5% elongation was 65 N / 5 cm (nonwoven fabric A on the needle penetration outlet side).

Two layers of nonwoven fabric obtained by the above production method are installed so that they can run in parallel, and glass fiber EC9 34 Z28 T30 (manufactured by VETROTEX) is placed between the two layers of nonwoven fabric at intervals of 0.3 cm. And installed so as to be able to run from the creel parallel to the longitudinal direction of the nonwoven fabric. Next, the glass fiber was used as an insertion yarn, and the two layers of nonwoven fabric and the insertion yarn were overlapped while running, and entangled with a neat punch machine. As the needle, an organ needle (FPD 1-40) was used, and the needle density was 50 / cm ² . Table 1 shows the properties of the obtained glass fiber reinforced laminated nonwoven fabric. The obtained laminated sheet has a width of 4% or less during asphalt impregnation when processed as asphalt roofing, and is a good base fabric.

(Example 2)
A laminated sheet was formed under the same processing conditions as in Example 1 except that the basis weight of the nonwoven fabric B was 60 g / m ² and the basis weight of the nonwoven fabric A was 40 g / m ² . Table 1 shows the properties of the obtained glass fiber reinforced laminated nonwoven fabric. The obtained laminated sheet has a width of 5% or less during asphalt impregnation when processed as asphalt roofing, and is a good base fabric.

(Comparative Example 1)
In Example 1, a laminated sheet was formed under the same processing conditions as in Example 1 except that the basis weight of the weakly press-bonded nonwoven fabric was 60 g / m ² and the two base fabrics were laminated. Table 1 shows the properties of the obtained glass fiber reinforced laminated nonwoven fabric. The obtained laminated sheet had a width of 10 to 14% or less during asphalt impregnation when processed as asphalt roofing, and there was a problem in securing and managing the specified width.

(Comparative Example 2)
The base fabric formed in Comparative Example 1 was impregnated with a mixed resin of urea melamine resin and acrylic resin by a conventional method, and heat treatment was performed to form a laminated sheet. Table 1 shows the properties of the obtained glass fiber reinforced laminated nonwoven fabric. The obtained laminated sheet has a width of 2% or less during asphalt impregnation when processed as asphalt roofing, and is a good base fabric. However, since the binder resin is impregnated when the laminated sheet is formed, the cost is excessively increased, and the handling and productivity of the binder resin are lowered.

  According to the present invention, since a laminated sheet suitable for use as a base fabric such as a waterproof material can be obtained at low cost, the initial strength is high and excellent in workability without any resin processing, and can be widely used. It is important to contribute to the industry.

Claims (7)

Reinforcing fibers are arranged between a nonwoven fabric (nonwoven fabric A) having a stress at 5% elongation of 40 N / 5 cm or more and a nonwoven fabric (nonwoven fabric B) having a stress at 5% elongation of 5 N / 5 cm to 30 N / 5 cm, and mechanical entanglement. A laminated sheet characterized by being laminated by a method. The laminated sheet according to claim 1, wherein the mechanical entanglement method is a needle punching method or a water punching method. The laminated sheet according to claim 2, wherein the nonwoven fabric B is disposed on a needle penetration inlet side or a water punch water inlet side in needle punching. The laminated sheet according to any one of claims 1 to 3, wherein a stress at 5% elongation after lamination is 60 N / 5 cm or more.   The laminated sheet according to any one of claims 1 to 4, wherein the nonwoven fabric A and / or the nonwoven fabric B is a nonwoven fabric that is thermocompression bonded. 6. The laminated sheet according to claim 1, wherein the nonwoven fabric A has a basis weight of 20 to 60 g / m ² and is 80% or less with respect to the nonwoven fabric B. The fineness of the fiber constituting the nonwoven fabric A is 1 to 4 dtex, and the fiber is strongly pressure-bonded by a roll having a temperature 40 to 10 ° C lower than the melting point of the resin constituting the nonwoven fabric A. The laminated sheet as described.