JP2004324010A - Tufted carpet base fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filament nonwoven fabric material, utilizable for applications in which occurrence of formaldehyde becomes a problem, having low release amount of formaldehyde to the environmental air and suitable for a tufted carpet base fabric, particularly for automobiles. <P>SOLUTION: The tufted carpet base fabric has 1.5-3.5 dtex fineness of filament and 3-30 mass% binder resin content and 70-200 g/m<SP>2</SP>basis weight and ≤0.50 μg formaldehyde amount released in the filament nonwoven fabric composed of synthetic resin filaments and a binder component for mutually fixing the filaments. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a long-fiber nonwoven fabric composed of a synthetic resin filament and a binder component capable of fixing the filament to each other, and suitable for a base fabric of a carpet or a flooring material. To a suitable base fabric.
[0002]
[Prior art]
A method using a binder component is widely adopted as a method for bonding and fixing fibers in a long-fiber nonwoven fabric. As a binder component, a method using an emulsion-type adhesive resin is the most common, and a self-crosslinkable resin is used. Are widely used in combination with a reactive group-containing resin and a crosslinking agent. These crosslinking components are methylol groups and cause formaldehyde generation.
[0003]
In recent years, there has been increasing public interest in the relationship between environmental air quality and various diseases such as allergies, and the problem of indoor air pollution in houses has been taken up as cases of sick house syndrome and sick building syndrome. In addition, formaldehyde, volatile organic compounds (VOC) and the like have become problems as indoor air pollutants.
In particular, regarding formaldehyde, the Ministry of Health and Welfare issued a guideline value for housing in 1997, and it has been clearly identified as a problem, and its source is used for wood, plywood, and interior materials, which are home building materials. It covers a wide range of fields, including adhesives, preservatives, termites, furniture and furniture in living spaces, daily necessities, and office equipment for business use.
As a formaldehyde countermeasure, a method of providing a formaldehyde adsorbent (Patent Document 1 and the like) and a method of coating a formaldehyde adsorbent (Patent Document 2 and the like) are known, but they are not sufficient measures.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. H11-046965 [Patent Document 2]
JP 2000-287819 A
[Problems to be solved by the invention]
The present invention will be regulated in various fields such as daily necessities, industrial materials, building materials, civil engineering materials, etc. in order to conform to the current situation in which the influence on the air quality of the environment must be considered. It is an object of the present invention to provide a long-fiber nonwoven material which has a low formaldehyde emission into the environment air and is suitable for a tufted carpet base fabric for automobiles, which can be used for an application which conforms to formaldehyde environmental standards.
[0006]
[Means for Solving the Problems]
That is, the present invention employs the following configuration.
1. In a long-fiber nonwoven fabric composed of synthetic resin filaments and a binder component for fixing the filaments to each other, the fineness of the filaments is 1.5 to 3.5 decitex, the binder resin content is 3 to 30% by mass, and the areal weight. A tufted carpet base fabric, which has a formaldehyde content of 70 to 200 g / m ² and an amount of released formaldehyde of 0.50 μg or less.
2. 2. The tufted carpet base fabric according to the above item 1, wherein the synthetic resin filaments are fixed to each other by heat and pressure, and further fixed by a binder component.
3. 2. The tufted carpet base fabric according to the above item 1, wherein the synthetic resin filaments are entangled with each other by a needle punch, and further fixed by a binder component.
4. 2. The tufted carpet base fabric according to the above item 1, wherein the synthetic resin filaments are entangled with each other by a needle punch, fixed by a binder component, and further fixed by heat and pressure.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The long-fiber nonwoven fabric in the present invention is a long-fiber nonwoven fabric obtained by a conventionally known manufacturing method such as a spunbonding method, and is mainly composed of a melt-spun filament from a spinneret having a large number of nozzle holes. is there.
As the synthetic resin forming the filament in the present invention, known synthetic fiber materials such as polyester, nylon, and polypropylene can be used, but polyethylene terephthalate, polybutylene terephthalate, etc. General polyesters such as homopolyesters and known polyesters having a copolymerization component in addition to these components are preferred.
These synthetic resin materials may contain a stabilizer, an ultraviolet absorber, a moisture absorbent, a lubricant, a pigment, and the like, but it is not preferable that these materials have a source of formaldehyde.
[0008]
The fineness of the synthetic resin filament is 1.5 to 3.5 dtex. If the fineness is smaller than 1.5 dtex, thread breakage is caused, and the operability is deteriorated. In addition, the number of bonded points and the density of bonded points are increased, and the breaking of the bonded points and the pulling due to the cutting of the fibers at the time of tufting. The drop in strength is large, and the penetration resistance of the needle during tufting becomes excessive. On the other hand, when the fineness is larger than 3.5 dtex, the eyes become large and the penetration resistance of the tuft needle becomes low, but the holding power of the pile yarn is reduced, and the entanglement of fibers and the contact point are reduced, so that the strength is reduced.
[0009]
The spun filaments are collected by a conveyor net or the like to form a web, and the filaments of the web are subjected to various processes such as heating by an emboss calender, pressure bonding, entanglement by a needle punch, binder resin treatment, etc. Are joined by joining means.
[0010]
The heating temperature by the emboss calendar is preferably in the range of −15 ° C. to −80 ° C. of the melting point of the synthetic resin, and in the case of polyester, it is preferably 180 to 250 ° C., and more preferably 200 to 230 ° C. By this treatment, effects such as stabilization of sheet transportability in the subsequent step of fixing with the binder component and reduction of the thickness of the sheet can be obtained.
[0011]
When performing the entanglement treatment by needle punching, the needle density of the needle punching is preferably set in the range of ^{20 to} 160 times / cm ² depending on the shape and insertion depth of the needle for needle punching, and more preferably 60 to 60 times / cm ^2. ~ 120 times / cm ² is preferred. When the needle density is less than 20 needles / cm ² , there is no effect of needle punching, and the strength and elongation are significantly reduced, so that distortion occurs in a subsequent processing step, which causes wrinkles and the like. On the other hand, if it exceeds 160 times / cm ² , the fibers and the bonding points are severely cut, and the strength is reduced.
[0012]
By adjusting the entangled state of the fibers by the needle punch, it is possible to impart characteristics such as a thicker sheet, a thinner sheet, and a difficulty in peeling the sheet in the thickness direction. The basis weight of the sheet before the binder resin treatment is 60 to 150 g / m ² , preferably 80 to 120 g / m ² . If the basis weight of this nonwoven fabric web is less than 60 g / m ² , physical properties such as tensile strength and stress at 5% elongation required as a base fabric for tufted carpet cannot be obtained, and the dimensional stability of the product carpet becomes low. . On the other hand, if the basis weight is too large, not only the excess physical properties will be uneconomical as a base fabric, but also the consumption of pile yarn will increase due to the increase in the thickness due to the increase in the basis weight, which is uneconomical as a product. In addition, an increase in the thickness causes a problem that penetration of the backing material into the base fabric is reduced, and thereby, the castability of the product is reduced.
[0013]
As the binder resin treatment, spraying, dipping, coating and the like can be appropriately selected. However, the pad-nip method in which the above-mentioned embossed calender or needle punched web is dipped in a binder resin treatment bath and then squeezed is preferable.
[0014]
As the binder resin, a polyester resin aqueous emulsion, an acrylic resin aqueous emulsion, or the like that does not become a source of VOC such as formalin or an organic solvent is preferable. Auxiliary agents such as a catalyst, a pH adjuster, a penetrant, an antifoaming agent, and a dispersant can be used in combination with the emulsion type resin, but those which do not generate formaldehyde are preferred.
[0015]
After the binder resin liquid has been applied, drying is usually performed at a temperature of about 80 to 130 ° C, followed by baking at 130 to 200 ° C for 1 to 10 minutes, preferably 150 to 180 ° C for 1 to 5 minutes. By performing the baking process, VOC can be significantly reduced.
[0016]
The solid content of the binder resin is 3 to 30% by mass, preferably 5 to 15% by mass, based on the total mass of the base fabric. When the solid content of the binder resin is less than 5% by mass, the tensile strength of the product is insufficient, and when it exceeds 30% by mass, the penetration resistance of the tufting needle during tufting is large, Further, the physical properties are significantly reduced due to the cutting of the constituent fibers, and the secondary workability and the dimensional stability after the product are reduced.
[0017]
After the processing of the binder resin, heat and pressure of a calender roller or the like are further applied to strengthen the fixing between the filaments, smooth the binder resin on the sheet surface, or impart an emboss pattern.
The basis weight as a carpet base fabric is 70 to 200 g / m ² , and the amount of formaldehyde released is 0.50 μg or less.
The amount of formaldehyde released in the present invention is measured by the following method.
[0018]
That is, this is the amount of formaldehyde released from the long-fiber nonwoven fabric having an area of 500 cm ² into 12 liters of nitrogen gas under a nitrogen gas flow atmosphere at a temperature of 70 ° C. with an air flow rate of 12 liters per hour. In other words, it measures the amount of formaldehyde generated from a certain area, not from a certain mass of the measurement sample, and the effect of indoor air pollution from a specific area of the wall, floor, ceiling, and other articles facing the working space. The evaluation is performed in a form as close as possible to the actual usage situation of the user receiving the information.
[0019]
The present invention combines the use of a non-formalin binder resin, which has hardly been practically used in this field, with an appropriate reduction in fineness, thereby increasing the entanglement of fibers in the needle punch and the effect of increasing the contact points between filaments. By aiming, it is possible to secure physical properties and workability comparable to the case where a conventional formalin-derived cross-linking agent is used. Conversely, in the conventional formalin-based binder resin, if the fineness of the long-fiber nonwoven fabric is reduced, the binding of the binder is too strong and the tufting property is impaired. However, such a defect is not recognized in the present invention.
The penetration resistance of the tuft needle at the time of tufting of the carpet base fabric of the present invention is preferably 8N or less, more preferably 6N or less.
[0020]
【Example】
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.
(1) The amount of formaldehyde generated is determined by the following method:
Take 5 cm × 10 cm × 10 pieces of long fiber non-woven fabric in a sampling container.
High-purity nitrogen gas was introduced at a rate of 0.2 ml / min at a temperature of the collection container of 70 ° C. and passed through a commercially available DNPH (2,4-dinitrophenylhydrazine) cartridge for 12 hours for 1 hour. And solid phase adsorption. A formaldehyde DNPH derivative is extracted from the cartridge with 5 ml of acetonitrile to prepare a sample solution.
The sample solution is introduced into a high performance liquid chromatograph (HPLC): HP1100 manufactured by Hewlett-Packard, and analyzed.
Other HPLC analysis conditions are as follows: Column: μBondapak C18 10 μm 125Å3.9 mm × 150 mm manufactured by Waters, mobile phase: water / acetonitrile = 45/55, flow rate = 0.8 ml / min, detection: UV 360 nm.
From the above, the amount of formaldehyde released into 12 liters of nitrogen gas from a long-fiber nonwoven fabric having an area of 500 cm ^{2 in} an atmosphere of nitrogen gas at a temperature of 70 ° C. with an air flow rate of 12 liters per hour is determined.
[0021]
(2) Penetration resistance:
The obtained carpet base fabric was fixed on a circular base with a belt, and one tufting needle was set on the upper chuck of an A & D RTC-1250 measuring instrument. The tufted carpet base fabric was perforated, and the load (N) at that time was measured. The tuft needle used was 0556FL manufactured by SNF Specialized Nadfabrik.
[0022]
(3) Tuft property evaluation:
Tufting is performed on the obtained carpet base fabric using 920 denier nylon pile yarn under the conditions of a gauge of 8/1 inch, a stitch number of 8/1 inch, and a loop pile height of 4 mm, to evaluate the tufting property. Was performed.
[0023]
[Example 1]
Polyethylene terephthalate is melt spun, a web is formed with a filament having a single yarn fineness of 2.2 dtex by a spun bond method, and subjected to needle punching (needle density 65 times / cm ² , needle depth 10 mm) and then non-formalin Acrylic resin of the type: VONCOAT ED-85 manufactured by Dainippon Ink and Chemicals, and DIC-SILICONE-SOFTNER 300 manufactured by Dainippon Ink and Chemicals, which is a silicone resin emulsion as a smoothing agent, are pad-nip-dried and dried. The resultant was baked at 160 ° C. for 3 minutes to obtain a base cloth having a basis weight of 100 g / m ² and an applied amount of a binder component of 10% by mass. As a result of measuring the amount of formaldehyde generated from this base fabric by the method described above, the amount of formaldehyde generated was 0.29 μg. The tuft needle penetration resistance was 5N.
Furthermore, when the tuft property of the obtained base fabric was evaluated, there was no problem at all.
[0024]
[Example 2]
Polyethylene terephthalate is melt spun, a web is formed with a filament having a single yarn fineness of 3.9 dtex by a spun bond method, followed by needle punching (needle density 65 times / cm ² , needle depth 10 mm), followed by heat with an emboss roller. After adhering (200 ° C.), it is fixed with a form-free type self-crosslinking acrylic resin (Acronal 2348 manufactured by BASF Dispersion Co., Ltd.) and the same smoothing agent as in Example 1 by the pad nip baking method as in Example 1. After the heat treatment, the resultant was further subjected to thermocompression bonding (205 ° C.) with a calendar roller to obtain a base cloth having a basis weight of 160 g / m ² and a binder component application amount of 15%.
As a result of measuring the amount of formaldehyde generated from this base fabric by the method described above, the amount of formaldehyde generated was 0.44 μg. The tuft needle penetration resistance was 6N.
Furthermore, when the tuft property of the obtained base fabric was evaluated, there was no problem at all.
[0025]
[Comparative Example 1]
Polyethylene terephthalate is melt spun, a web is formed with a filament having a single fiber fineness of 3.9 dtex by a spun bond method, and thermally bonded with an emboss roller, and then an acrylic resin having a general crosslinking reactivity and a melamine resin as a crosslinking agent are used. Then, the mixture was fixed by a pad nip baking method in the same manner as in Example 1 using a preparation solution containing a tertiary amine as a catalyst, and then subjected to thermocompression bonding (205 ° C.) with a calender roller, and a binder having a basis weight of 100 g / m ² . A base cloth having a component application amount of 10% was obtained.
As a result of measuring the amount of formaldehyde generated from this base fabric by the method described above, the amount of formaldehyde generated was 9.17 μg. The tuft needle penetration resistance was 12N.
[0026]
[Comparative Example 2]
A base fabric was obtained in the same manner as in Example 1 except that the single-fiber fineness was set to 4.0 dtex. Further, when the tuft property of the obtained base fabric was evaluated, it was found that the holding power of the pile yarn was low and the properties as the base fabric were inferior.
[0027]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the amount of formaldehyde discharge | release to environment can be provided and the base fabric for carpets excellent in tuft property can be provided, and this base fabric is suitable especially for carpet of a motor vehicle.

Claims (4)

In a long-fiber nonwoven fabric composed of a synthetic resin filament and a binder component for fixing the filament to each other, the filament fineness is 1.5 to 3.5 dtex, the binder resin content is 3 to 30% by mass, and the basis weight is 70. -200 g / m < ² > and the amount of formaldehyde released is 0.50 [mu] g or less. The tuft carpet base fabric according to claim 1, wherein the synthetic resin filaments are fixed to each other by heat and pressure, and then further fixed by a binder component. The tufted carpet base fabric according to claim 1, wherein the synthetic resin filaments are entangled with each other by a needle punch, and further fixed by a binder component. The tuft carpet base fabric according to claim 1, wherein the synthetic resin filaments are entangled with each other by a needle punch, fixed by a binder component, and further fixed by heat and pressure.