JPH09256256A - Membrane and substrate therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonwoven fabric suitable for a membrane substrate excellent in air permeability and waterproof effects by carrying out the needle punching treatment of a spunbonded web comprising conjugated fibers containing a low-melting resin arranged in a sheath part and a high-melting resin arranged in a core part and further performing thermal embossing processing. SOLUTION: This substrate for a membrane is obtained by carrying out the conjugated spinning of a low-melting isophthalic acid copolymer arranged in a sheath part and a high-melting polyethylene terephthalate arranged in a core part into a sheath- core type at (5:95) to (70:30) ratio of the low-melting component to the high-melting component, providing filaments of 1-10de size, pulling the filaments with an ejector at a high speed, depositing the filament on a moving conveyor, forming a web, subsequently performing the needle punching treatment of the formed web, affording a nonwoven fabric, then passing the resultant nonwoven fabric through an embossing device composed of the upper roll which is heating roll and the lower roll that is a cooling roll, interlacing and melting sticking the constituent filament of <5de average size on the surface of the nonwoven fabric in contact with the upper roll and forming fuzzes or loops from the filaments of >=5de size on the surface in contact with the lower roll. The resultant substrate for the membrane has >=10cc/cm<2> /sec, preferably 15-35cc/cm<2> /sec air permeability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a well-balanced base material for a membrane material, which is excellent in sheet strength, resin coating property, and deaeration of water from a mortar layer or a concrete layer, and a membrane material comprising the same. . More specifically, for buildings such as roofs, tents, and agricultural houses,
Further, the present invention relates to a film material used for bags and various covers.

[0002]

2. Description of the Related Art Conventionally, continuous filaments have been pulled at high speed by air sucker, etc., and then opened and collected on a collecting net to obtain a nonwoven fabric web, which is then heat-bonded by an embossing roll or mechanically filamentized by a needle punch. The so-called spun-bonded non-woven fabric which is entangled with the non-woven fabric is in strong demand in all applications such as woodworking material application, construction material application and industrial material application.

Among them, the demand for building materials is sharply growing, such as strength, breathability, water permeability, and roofing coating film waterproofing which is waterproofed by post-processing such as asphalt. That is, in the case of a roofing base material that has been conventionally used as a waterproof material on the roof of an office building, since the roof mortar layer or cement layer and the asphalt layer of the roofing lack air permeability, the mortar layer or There is a problem in the waterproof effect such as the floating of the roofing layer due to the thermal expansion of the steam generated from the cement layer or the air between the mortar layer and the asphalt layer of the roofing. In order to eliminate these drawbacks, a waterproof sheet composed of a breathable non-woven fabric layer between the mortar layer or cement layer and the waterproof resin layer, that is, a waterproof base material for coating film is considered promising. became.

Conventionally, as a waterproof substrate for coating film, for example, a needle-punched non-woven fabric and a film are laminated and a thermo-adhesive non-woven fabric is laminated, or a mixed fiber type of filaments having a low melting point component and a filament having a high melting point component. After needle-punching the non-woven fabric web, the one side is thermo-compressed with an embossing roll and the polyurethane film is further laminated, or the polyester film or nylon film forming the surface layer is laminated with the synthetic fiber non-woven fabric using an appropriate adhesive. Method, composite film made by laminating polyethylene film or polypropylene film on polyester film or nylon film, or composite film made by extruding polyethylene resin or polypropylene resin on polyester film or nylon film and coating. Various waterproofing membrane substrates such as direct heat-sealed substrate to the surface of the nonwoven fabric have been proposed.

[0005]

However, a needle-punched nonwoven fabric and a film laminated together, and further a heat-bonded nonwoven fabric laminated together, involve a laminating step, which causes a problem of high cost and a low melting point component. In the method of needle-punching a nonwoven fabric web made of a mixed filament of filaments composed of a filament composed of and a filament composed of a high melting point component and then thermocompressing one surface with an embossing roll, it is composed of a low melting point component fiber and a high melting point component fiber. When needle-punching, filaments consisting of low-melting-point components, which are stronger and weaker than high-melting-point filaments, are easily cut, and the entangled state and sheet thickness after needle-punching are likely to vary. When heat-bonding, there are variations in the thermocompression bonding state, See variations not only workability when is laminated on the mortar as waterproofing membrane base material, and therefore larger, there is a possibility that it becomes missing septum on quality.
Furthermore, due to the insufficient thickness of the nonwoven fabric after needle punching, thermocompression bonding becomes insufficient, fuzz occurs on the thermocompression bonding surface, and the coating property of synthetic resin such as polyurethane deteriorates. Therefore, unless the resin is added more than necessary. There was a problem such as disappearing.

[0006] Further, there is a needle punched non-woven fabric composed of a single component of polyester or polypropylene, polyester or nylon film, or a composite film obtained by laminating a polyethylene film or polypropylene film to a polyester film or nylon film, which involves many steps. Therefore, there is a problem that the cost becomes very high.

In view of such problems of conventional membrane materials, the present invention provides a well-balanced sheet thickness, excellent sheet strength, resin coating property, and deaeration of water from a mortar layer or a concrete layer. The present invention also provides a base material for a film material and a film material made of the same.

[0008]

The present invention employs the following means in order to solve the above problems. That is, the base material for a membrane material of the present invention is a base material for a non-woven fabric material comprising a core-sheath filament composed of a core component having a high melting point component and a sheath component having a low melting point component. One surface is formed with fluffs or loops, and the other surface is embossed.
The film material of the present invention is characterized in that the embossed surface of the film material base material is covered with a synthetic resin film.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, as a result of earnest studies on a base material for a film material which is excellent in degassing of water from a mortar layer or a concrete layer, it is found that the resin liquid is not permeated and only the surface portion is stopped. Focusing on, using a core-sheath filament non-woven fabric with a high-melting point component as the core component and a low-melting point component as the sheath component, the resin-coated surface was embossed. It is a solution to the problem.

The polymer used for the sheath component of the present invention may be any of polypropylene, polyethylene and the like as long as the melting point is lower than the high melting point component by 25 to 50 ° C., but from the viewpoint of spinning stability, it is either an isophthalic acid copolymerized polyester or an adipic acid copolymer. Polymerized polyesters are preferred. When the core component of the filaments constituting the nonwoven fabric used as the base material for the film material is the high melting point component and the sheath component is the low melting point component, the ratio of the low melting point component and the high melting point component is 5:95 to 70. : 30 is preferable. That is, the ratio of the low melting point component is 5
If the content is less than 5% by weight, the sheath component cannot be completely covered around the core component, which not only deteriorates the spinnability but also causes unstable adhesion between filaments, resulting in partial fluffing. It may not be possible to obtain a satisfactory base material. On the other hand, when the ratio of the low melting point component exceeds 70% by weight, the ratio of the low melting point component is increased, so that the solidification point at the time of spinning is lowered, yarn breakage occurs due to insufficient cooling, and operability is deteriorated. In addition, the strength of the filament itself becomes low, the fiber is easily cut in the needle punching process, and the processing characteristics such as heat shrinkage during heat treatment vary, so that stable production is impossible.

The difference in melting point between the low melting point component and the high melting point component in the present invention is preferably in the range of 25 ° C to 50 ° C. When the melting point difference is less than 25 ° C., the heating roll temperature must be sufficiently high in order to satisfy the fluff prevention of the heat-bonded surface and the brush wettability of the waterproof resin in the heat-bonding step after needle punching. That is, if the treatment temperature is too low, the anti-fluffing effect is low and the heat-adhesive layer is thin, so that the waterproof resin needs to be coated with a large amount of resin in order to penetrate into the interior and have the waterproof effect, and the resin is also wet. This causes problems such as long working time.

When the difference in melting point exceeds 50 ° C., the solidification point of the filament discharged from the spinneret becomes low, so that the spinnability deteriorates due to fusion bonding of the filaments due to yarn breakage, and the strength of the filament decreases. It is easy to cut the filament with a needle punch, and there is a large amount of fluff and thickness loss during heat treatment. I will end up.

The denier of such filaments constituting the substrate for the nonwoven fabric film forming material of the present invention is preferably 1 to 10 denier. If the denier of the filament is less than 1 denier, it cannot follow high-speed spinning at 5000 m / min due to the fine denier, which causes operational problems such as spinning yarn breakage. The heat-treated surface has a dense adhesive surface and has good resin coating properties, but the non-heat-bonded surface has a fine denier, which results in low porosity, and therefore lacks breathability and moisture permeability, and resin coating properties. In addition, the problem of poor deaeration of water from the mortar layer or concrete layer is likely to occur.
When the denier of the filament exceeds 10 denier, the non-heat-bonded surface has a high porosity and is excellent in breathability and moisture permeability, but the thermocompression bonded surface lacks denseness, and therefore resin penetration becomes high. However, there is a problem that a large amount of resin is required for forming a film and workability for resin application is deteriorated.

That is, there is obtained no fluff on the heat-bonded surface, high denseness, good workability of applying the waterproof resin by brushing, good air permeability on the non-heat-bonded surface, and good water-repellent coating film base material. In order to improve air permeability and water permeability, the non-thermocompression bonding surface in contact with the mortar surface has a high denier of 5 denier or more for the constituent filaments, while the thermocompression bonding surface has no fluff. In order to improve the film coatability and waterproofing effect of the waterproof resin, it is preferable to make the denier of the constituent filaments as low as less than 5 denier. Such a fineness gradient is provided at least 2 or more, that is, a nonwoven fabric having a laminated structure of at least 2 layers is used. Is more effective.

The adhesive thickness of the thermocompression-bonded portion is preferably 10 μm or more from the viewpoint of suppressing the resin permeability and improving the brush coating property, and the air flow rate is preferably 10 cc / cm 2.
² / sec or more, more preferably 15 to 100 cc / cm ² / s
ec, particularly preferably 15 to 35 cc / cm ² / sec. The air permeability here is the air permeability in the plane direction of the nonwoven fabric. In order to achieve the degassing of water from the mortar layer or the concrete layer, those having such air permeability are preferable.

According to the present invention, the high melting point component is the core component,
A core-sheath type filament having a low melting point component having a lower melting point of 25 ° C. to 50 ° C. as a sheath component is used. Therefore, when needle compression is performed on one side after needle punching, the thermal bonding property between the filaments is good and the waterproof resin. It has excellent workability such as brushing property, and has a great improvement effect such as exhibiting waterproof effect due to low resin penetration into the nonwoven fabric.

The filament of the present invention is preferably colored, and for example, the entire filament may be used, but it is preferable that carbon black is contained in the polymer forming the core component. Such coloring is affixing the base material for the film material to the mortar layer or cement layer on the roof of the building,
This is because, when the resin is applied and waterproofed, if the base material is white, snowflakes will occur due to sunlight, which will be an obstacle to work. The density may be sufficient, and the addition amount also differs depending on the type of color and whether it is a pigment or a dye. For example, carbon black is achieved by adding 0.00005% (5 ppm) or more, preferably 0.01% by weight or more, and more preferably 0.1% by weight or more. Such a colorant is preferably contained in the core component in terms of fading properties and the like. The film material of the present invention is such that the embossed surface of the film material base material is covered with a synthetic resin film. Such a synthetic resin film is preferably formed from a coating film, that is, a resin liquid applied from the viewpoint of workability. In this case, it is preferable that the synthetic resin has a structure in which the synthetic resin remains on the surface layer of the embossed surface and does not exist in the central portion from the viewpoint of water deaeration. The synthetic resin may be any resin that is usually used for resin processing, but for example, at least one selected from urethane resins and acrylic resins is preferably used.

[0018]

EXAMPLES The present invention will be described in detail based on the following examples, but it goes without saying that the present invention is not limited to the following examples.

The evaluation method of each characteristic in the examples is as follows.

(1) Spinning stability When the number of spinning yarn breaks is 20 times / ton or less: ○,
Those with 21 to 50 times / ton were marked with Δ, and those with more than 50 times were marked with ×.

(2) Stability of heat treatment When heat-treating with an embossing roll, a sheet having no heat-treated surface on the upper embossing roll and having extremely stable workability: ○, a sheet on the upper embossing roll When the occurrence of peeling is partially generated but there is no problem in processing, it is indicated by: Δ, and when the sheet is peeled off on the upper embossing roll over the entire width and stable production is impossible, it is indicated by ×.

(3) Punching property When punching with a punching machine having a hole diameter of 5 mmφ and widths of 15 mm in each of the width direction and the length direction, those that are completely punched are ○, and some fibers remain uncut. The evaluation was evaluated as Δ when there were unprinted marks and × when there were many unprinted marks.

(4) Aeration amount (cc / cm ² / sec) JIS L 1096 (method A) Frazier type tester was used to collect test pieces each having a size of 15 × 15 cm N = 3
Was measured and the average value was taken as the air flow rate.

Examples 1 to 20 Polyethylene terephthalate having an intrinsic viscosity of 0.66 and a melting point of 262 ° C. was used as a high melting point component and an intrinsic viscosity of 0.7.
Spinning in which a core-sheath type spinneret having a discharge hole diameter of 0.5 mm and a number of holes of 160 holes was arranged after isophthalic acid copolyester having a melting point of 230 ° C. was used as a low melting point component and melted at 285 ° C. The discharge amount of the high-melting point component and the low-melting point component was changed by using the device, and the single yarn denier (d) was 0.
8d, 1.0d, 1.2d, 2d, 3d, 5d, 8d,
10d and 13d, the ratio of the low-melting point component and the high-melting point component was changed so that the respective ratios were 3/97, 5/95, 1
It is adjusted to 0/90, 20/80, 30/70, 40/60, and after cooling the filament, it is towed at a high speed by an ejector and jetted and collected on a moving net conveyor. The net conveyor speed was adjusted so as to be m ^2, and a nonwoven sheet sheet was obtained while appropriately adjusting the thickness with a calendar roll having a roll temperature of 130 ° C.

Then, the needle punching device is used for upper / lower 60 each.
After carrying out needle punching of 1 book / cm ² into a non-woven fabric with one side having a loop formed by needle punching, an upper roll temperature is 225 ° C. and a lower roll is a cooling roll. Heat treatment was carried out at / cm. On one side of the sheet that is in contact with the high temperature upper roll surface of this embossing roll, the filaments on the surface are fused alternately, there is no surface fluff, and the low temperature side in contact with the lower roll has a loop of filaments formed by needle punching. It was left as it was, and no fusion of filaments was observed.

Each of the non-woven fabric sheets obtained has a hole diameter of 5
With a diameter of mm, punching was performed at 15 mm pitches in the width direction and the length direction to obtain a substrate for a film material.

The punching property during punching was also good.

The obtained film base material was tightly placed on the rooftop mortar layer, and a waterproof material containing an acrylic rubber emulsion as a main component was applied thereto to evaluate workability and waterproof performance such as brushing property and adhesive fixing property. .

The results such as processing stability and quality characteristics in each process are shown in Table 1.

[0030]

[Table 1] In these examples, the spinnability was good when the ratio of the low melting point component to the high melting point component was in the range of 5:95 to 70:30, and the filament single yarn denier was 1 to 10 denier and the air flow rate was 100 cc / Those having a cm ² / sec or less were good in the brush coating property of the waterproofing material containing the acrylic rubber emulsion as the main component, and the waterproofing property was also good.

Comparative Examples 1 to 12 Using the same raw material as in the examples and using a mixed fiber die having 160 holes in the die, the ratio of the high melting point component and the low melting point component is 0,
Adjusting the discharge rate so that the single yarn denier of the filament becomes 10 denier by changing to 10, 20, 30%, spinning, cooling the filament, and then collecting it on a moving net conveyor that is pulled by an ejector at high speed. 300 g /
The net conveyer was adjusted to m ² and the thickness was adjusted with a calendar roll having a roll temperature of 180 ° C., and then a non-woven fabric sheet was obtained.

Continuously, the needle punching device is used for upper / lower 60 each.
A needle punch of books / cm ² was laid to produce a non-woven fabric having a loop formed on one side.

Thereafter, the temperature of the lower embossing roll is set to 80 ° C., and the temperature of the upper embossing roll is set to 225 ° C., 230 ° C., 235
C. and 245.degree. C. were changed and heat treatment was performed.

When the low melting point component is 20% or 30%, there is a problem in operation such as the sheet sticking to the roll at an embossing roll temperature of 235 ° C. or higher. I had a similar problem.

The non-woven fabric sheet thus obtained was punched at a hole diameter of 5 mmφ and a pitch of 15 mm in each of the width direction and the length direction to obtain a base material for a film material.

Table 2 shows the results of evaluation of the brush coating property and adhesive fixability of the waterproof material mainly composed of acrylic rubber emulsion, which was spread on the rooftop mortar layer.

[0037]

[Table 2] In these comparative examples, those containing no low melting point component were not usable because the filaments hardly adhered to each other even when the heat treatment temperature was increased, and there were many fluffs and the punching property and the brush coating property were poor.

Even in the case where the low melting point component is mixed in an amount of 10 to 30%, the heat adhesion on the heat treated surface is insufficient even if the heat treatment conditions after needle punching are optimized, and both the punching property and the brushing property are excellent for the film material base. There was nothing satisfactory as a material.

Example 21 Using the same raw material and spinneret as in Examples 1 to 20, the filament denier of the lower layer of the sheet was 6 denier and the upper layer of the sheet was A non-woven sheet material having a denier of 2 and a basis weight of 300 g / m ² was moderately adjusted in thickness with a calendar roll having a roll temperature of 130 ° C.

Subsequently, needle punches of 60 lines / cm ² for each of the upper / lower sides are provided, and the upper surface of the sheet having a denier of 2 is brought into contact with the upper roll by an embossing roll having an upper roll temperature of 225 ° C. and a lower roll temperature of 80 ° C. Was heat treated.

When the obtained base material had a hole diameter of 5 mmφ and was punched at a pitch of 15 mm in each of the width direction and the length direction, the punching property was extremely good, and the acrylic rubber emulsion when it was attached to the mortar layer. The brushing property of the waterproof material containing as a main component was extremely good.

Example 22 Polyethylene terephthalate having an intrinsic viscosity of 0.66 and a melting point of 262 ° C. was mixed with 0.2% by weight of carbon black (2
(000 ppm) was added to the core component, and the isophthalic acid copolyester having an intrinsic viscosity of 0.70 and a melting point of 230 ° C. was used as a sheath component to prepare a base material for a membrane material under the same conditions as in Examples 1 to 22. Obtained.

Since the core component of the obtained base material was colored with carbon black, the workability was extremely good without snowing when applied to the rooftop mortar layer.

Example 23 The heat-treated surface of the substrate for film material obtained in Example 21 had a thickness of 10 μm.
A polyurethane film was coated to obtain a film material.

As a result of applying the obtained membrane material to the rooftop mortar layer, the waterproofness was good, and the air permeability of the water vaporized from the mortar layer after application was also good, showing good performance as the membrane material.

[0046]

Industrial Applicability According to the present invention, it is possible to provide a non-woven fabric which has good thermal adhesion between filaments and excellent brushing property of the waterproof resin, and has less penetration of the resin into the non-woven fabric and excellent waterproof effect.

Claims (15)

[Claims] 1. A non-woven fabric base material comprising a core-sheath filament composed of a core component having a high melting point component and a sheath component having a low melting point component, and a fluff or loop is formed on one side of the non-woven fabric. The base material for film material is characterized in that the other surface is embossed. 2. The base material for a film material according to claim 1, wherein the core-sheath filament has a ratio of the low melting point component and the high melting point component of 5:95 to 70:30. 3. The base material for a film material according to claim 1, wherein the core-sheath filament has a fineness of 1 to 10 denier. 4. The substrate for film material is 10 cc / cm in the plane direction.
^The base material for a film material according to claim 1, which has an air permeability of ² / sec or more. 5. The base material for a film material is 15 to 35 in the plane direction.
The base material for a film material according to claim 1, which has air permeability of cc / cm ² / sec or more. 6. The average fineness of the filaments constituting the embossed surface is less than 5 denier.
The base material for a film material described. 7. The substrate for a film material according to claim 1, wherein the filament constituting the surface on which the fluff or loop is formed has an average fineness of 5 denier or more. 8. The substrate for a film material according to claim 1, wherein the filament is colored. 9. The colored component is the core component.
The base material for a film material described. 10. The substrate for a film material according to claim 9, wherein the core component contains carbon black. 11. The substrate for a film material according to claim 1, wherein the filament is a polyester fiber. 12. A film material, wherein the embossed surface of the film material base material according to claim 1 is covered with a synthetic resin film. 13. The synthetic resin film is a coating film.
The membrane material according to 2. 14. The membrane material according to claim 13, wherein the synthetic resin substantially remains on at least the surface layer of the embossed surface and does not exist in the central portion. 15. The film material according to claim 12, wherein the synthetic resin is at least one selected from urethane resins and acrylic resins.