JPS6215386A - Fire self-extinguishing nonwoven fabric - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a nonwoven fabric having self-extinguishing properties.

More specifically, it has excellent self-extinguishing properties, high-frequency adhesive properties, good texture, light discoloration resistance, and has a non-sticky surface, making it suitable for interior materials for automobiles, vehicles, and buildings, and for electrical equipment. The present invention relates to nonwoven fabrics that are particularly useful in applications that require high flame retardant performance and suitability for high-frequency processing, such as insulating and heat-insulating materials.

[Conventional technology]

Nonwoven fabrics are used as interlining, lining, base fabric, and covering materials for various interior materials and clothing materials, as well as electrical insulation materials and
It is widely used in insulation materials, medical and sanitary materials, filters, sound-absorbing materials, cushioning materials, packaging materials, civil construction materials, and other industrial materials, and demand is rapidly expanding by taking advantage of its versatility and economic efficiency.

Flame retardant regulations have been put in place for final products using nonwoven fabrics depending on their use, and flammability is particularly strictly regulated both domestically and internationally for automobiles, vehicles, aircraft, building materials, and electrical equipment. Flame-retardant processing of non-woven fabrics has been carried out in the past in order to clear flame-retardant regulations, but it is sufficient that the final product or composite material satisfies the flame-retardant standards. This was not a big problem because the demands were weak. However, in recent years, with the tightening of flame retardant regulations, a high degree of flame retardancy such as self-extinguishing properties has come to be required for nonwoven fabrics alone, including automobile interior materials.

Methods for making non-woven fabrics flame retardant include (a) a method of manufacturing non-woven fabrics using flame-retardant synthetic fibers including kneading of flame retardants, and (b) post-treatment methods such as coating and impregnation with flame retardants. be. No matter which method is used to impart self-extinguishing properties to a nonwoven fabric, there are problems in that physical properties such as texture, dimensional stability, and color fastness are impaired, and the cost becomes high and the properties of the nonwoven fabric are lost.

On the other hand, in the aforementioned fields of automobiles, building materials, electrical equipment, etc., there has been a growing demand for flame retardancy as well as suitability for high-frequency adhesive processing. For example, interior materials consisting of two or three or more layers of composite materials, such as combinations of (a) surface material, (b) core material/cushion material, and (d) base material/lining material, have different patterns and configurations. Processing methods using high-frequency adhesives are becoming mainstream due to their versatility and production efficiency. Therefore, when nonwoven fabrics are used as any of the above-mentioned materials (a), (b), and (ii), the nonwoven fabrics are required to have excellent suitability for high-frequency adhesive processing.

When polyamide fibers are used as a material for nonwoven fabrics, although they have a certain degree of high frequency sensitivity, their high melting point results in poor adhesion, and if the welding time is prolonged to obtain sufficient adhesive strength, sparks, which are called sparks, may occur. There is a problem in that the discharge phenomenon of seeds causes damage, discoloration, and holes in the composite material.

Of course, nonwoven fabrics made of fibers with poor high frequency sensitivity, such as polyester, cupro, rayon, polypropylene, and acrylic, have the disadvantage that high frequency adhesive processing cannot be applied at all.

In JP-A No. 60-25739, high-frequency adhesive properties are imparted to a nonwoven fabric by coating, impregnating, or mixing a vinyl chloride copolymer and/or vinylidene chloride copolymer composition onto a base material such as a nonwoven fabric. It is proposed that. Although this method improves high-frequency adhesion, it lacks consideration of various required physical properties such as flame retardancy, and has the following problems.

(a) M has insufficient flammability and does not have self-extinguishing properties.

Increasing the amount of flame retardant added will sacrifice high frequency adhesion.

(b) It has poor light resistance and cannot withstand use under sunlight.

(1) Strong tackiness and stickiness lead to decreased productivity during processing and decreased product value.

(d) Harden the texture.

[Problem that the invention seeks to solve]

In applications that require high flame retardant performance and suitability for high-frequency processing, such as interior interior materials for automobiles, vehicles, and buildings, and insulating and heat-insulating materials for electrical equipment, current nonwoven fabrics cannot satisfy these required physical properties. There wasn't. Therefore, there has been a strong desire to develop a nonwoven fabric that has high flame retardancy (self-extinguishing properties), high-frequency adhesion, light discoloration resistance, non-tackiness, and texture. An object of the present invention is to provide such a nonwoven fabric.

[Means and effects for solving the problems] The present inventors
As a result of extensive research in order to provide a nonwoven fabric with excellent self-extinguishing properties, high-frequency adhesion, light discoloration resistance, non-tackiness, and texture, we have determined the composition of vinylidene chloride resin latex, inorganic hydrous compound, and The present invention was completed based on the discovery that a nonwoven fabric with a certain ratio of reached.

That is, the present invention has a resin component having the following composition: 50 to 85% by weight of vinylidene chloride units, 2 to 25% by weight of acrylonitrile units, 45% by weight of vinyl monomer units, and a resin solid content of 25 to 70% of vinyl monomer units. A mixture of 30 to 75% by weight of an inorganic water-containing compound with an average particle size of 20 μm or less is 2 parts by weight per 100 parts by weight of the raw nonwoven fabric in terms of dry weight.
The present invention relates to a self-extinguishing nonwoven fabric having 5 to 100 parts by weight attached thereto.

The main points of the present invention are that (a) the composition of the vinylidene chloride resin latex has been specified and (b) the latex and an inorganic hydrous compound are combined in a processing agent applied to the processing of nonwoven fabrics. By containing a specific monomer unit called vinylidene chloride/acrylonitrile in a specific ratio, vinylidene chloride resin latex exhibits excellent flame retardancy, high frequency adhesion, light discoloration resistance, and non-tackiness. By combining the latex with an inorganic hydrous compound having a specified average particle size, self-extinguishing properties and a good texture can be imparted to the nonwoven fabric at low cost while preserving high-frequency adhesion.

"Self-extinguishing property" described in the present invention is JIS-D.12
It refers to self-extinguishing property at 0.01 or high flame retardancy exceeding 27 on flame retardant index (oxygen index).

The "nonwoven fabric" described in the present invention refers to nonwoven fabrics obtained by various manufacturing methods such as dry method, wet method, or direct method described in Fiber Handbook Processing Report (edited by Fiber Science Society of Japan: Maruzen) ■-6.
Includes non-woven fabric products such as artificial leather.

The "vinylidene chloride resin latex" described in the present invention refers to an aqueous dispersion of vinylidene chloride copolymer having an average degree of polymerization of 100 or more obtained by emulsion polymerization. The vinylidene chloride resin latex of the present invention contains 50 to 85% by weight of vinylidene chloride units and 2 to 85% by weight of acrylonitrile units.
25% by weight, and 7 to 45% by weight of vinyl monomer units. If the vinylidene chloride unit content is less than 50% by weight, flame retardancy and high frequency adhesion will be insufficient, and if it exceeds 85% by weight, the discoloration property, especially light resistance to discoloration, will be impaired due to the localization of the vinylidene chloride unit.

Acrylonitrile unit is very preferable in terms of improving flame retardancy, and it moderately raises the glass transition point of the resin and improves non-tackiness, that is, stickiness, but the effect of introduction is not expressed unless it reaches 2% by weight. If it exceeds % by weight, film formability, high-frequency adhesion, texture, and heat resistance to discoloration will be impaired.

The vinyl monomer unit is a unit of other vinyl monomers copolymerizable with vinylidene chloride and/or acrylonitrile, and includes (meth)acrylic acid alkyl esters such as methyl acrylate (or methacrylate), (meth) Unsaturated carboxylic acids such as acrylic acid, hydroxyalkyl esters of unsaturated carboxylic acids such as hydroxyethyl (meth)acrylate, amide derivatives of unsaturated carboxylic acids such as (meth)acrylamide, and unsaturated carboxylic acids such as N-methylol (meth)acrylamide. N- of saturated carboxylic acid
Alkylolamide derivatives, (mono, di, or tri)
Di(meth)acrylate such as ethylene glycol di(meth)acrylate
Examples include esters of unsaturated carboxylic acids such as meth)acrylate and tri(meth)acrylate, as well as methacrylonitrile, styrene, vinyl chloride, divinylbenzene, and the like.

Considering cost performance, industrial applicability, and high flame retardancy, the following chlorine-containing or nitrogen-containing monomer components, such as vinyl chloride, methacrylonitrile, and acrylic acid amide, are recommended as vinyl monomer units. Vinyl monomers having a nitrogen content of 8% by weight or more, such as , methacrylic acid amide, and N-phenylmaleimide, are preferred. In addition, 1-chloroacrylonitrile containing chlorine as well as acid amide groups and nitrile groups, and allyl cyanurate, a vinyl monomer containing a large amount of melamine rings, can be advantageously used.

The lower limit of the content of vinyl monomer is not particularly limited, but 4
If it exceeds 5% by weight, the physical properties of the vinylidene chloride resin latex intended by the present invention, such as flame retardancy, high frequency adhesion, light discoloration resistance, and non-tackiness, cannot be balanced.

The composition of the vinylidene chloride resin latex is 60-80% by weight of vinylidene chloride units, 5-20% by weight of acrylonitrile units, and 35% by weight of vinyl monomer units, in view of the balance of various physical properties including flame retardancy and high-frequency adhesion.
It is more preferably less than % by weight.

The vinylidene chloride resin latex of the present invention may be prepared by a single polymerization process or may be obtained by blending two or more latexes. A 2-step polymerization method as described in Japanese Patent Application No. 60-77942 previously proposed by the present inventors,
It is preferable to appropriately localize each unit of vinylidene chloride and acrylonitrile by a method such as a latex blending method when excellent light resistance to discoloration is required. In particular, in the two-step polymerization method, latex prepared by introducing a large amount of vinylidene chloride units in the first step and a large amount of acrylonitrile units in the second step has excellent self-extinguishing properties, high-frequency adhesion, and resistance to light discoloration. It is preferable because it has a well-balanced combination of elasticity, texture, and non-tackiness.

The inorganic hydrous compound used in the present invention has an average particle size of 20 μm or less as measured by the Andreasen pipette method. If the average particle size exceeds 20 μm, sufficient flame retardancy cannot be obtained and high frequency adhesion is hindered. Examples of the inorganic hydrous compound include aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, etc., and these are used singly or as a mixture of two or more. Considering the effect on flame retardancy, effect on high frequency adhesion, effect on non-tackiness, texture, texture, transparency, etc., the inorganic hydrous compound to be combined with vinylidene chloride resin latex should have an average particle diameter of 10 μm or less. Particularly preferred is aluminum hydroxide.

The self-extinguishing nonwoven fabric of the present invention comprises a mixture consisting of 25 to 70% by weight of the resin solid content of the vinylidene chloride resin latex of the present invention and 30 to 75% by weight of the inorganic hydrous compound of the present invention, on a dry weight basis. It is necessary to apply 25 to 100 parts by weight per 100 parts by weight of the original nonwoven fabric. If the resin solid content of the vinylidene chloride resin latex in the mixture is less than 25% by weight (the inorganic water-containing compound exceeds 75% by weight), the inorganic water-containing compound cannot be bound to the nonwoven fabric, and furthermore, the high frequency adhesion is poor. It disappears. If it exceeds 70% by weight, flame retardancy and texture will be impaired. A nonwoven fabric with less than 25 parts by weight of the mixture will lack flame retardancy and high-frequency adhesive properties, will not have self-extinguishing properties, and will not be able to be processed using high-frequency waves. If it exceeds 100 parts by weight, the texture of the nonwoven fabric will be significantly impaired and the cost will increase significantly. Resin solid content of vinylidene chloride resin latex of the present invention 3
More preferably, 30 to 80 parts by weight of a mixture consisting of 0 to 65% by weight and 35 to 70% by weight of an inorganic hydrous compound are attached.

A mixture of vinylidene chloride resin latex and an inorganic water-containing compound may be prepared by preparing a pre-mixed compound and impregnating or coating the non-woven fabric and then drying and adhering it, or when manufacturing the non-woven fabric using a wet process, the inorganic water-containing compound may be applied. The compound may be used as a filler and vinylidene chloride resin latex as a binder, which may be mixed and then dried and attached. Furthermore,
Commercially available flame retardants such as antimony oxide, halogenated phosphate esters, nitrogen-containing compounds, and synthetic resin latex may be used in combination.

The fiber materials of the self-extinguishing nonwoven fabric of the present invention include synthetic fibers such as nylon, polyester, acrylic, and polyolefin, recycled fibers such as carburetor and rayon, and natural fibers such as wool and hemp. is used. In the above-mentioned field of application of the present invention, from the viewpoint of physical properties and economical efficiency, it is preferable to obtain the self-extinguishing nonwoven fabric of the present invention using a raw nonwoven fabric made of nylon or polyester fibers and having a basis weight of 30 to 300 g/nf. is preferred.

〔Example〕

The present invention will be explained in more detail with reference to Examples below, but it goes without saying that the present invention is not limited only to the Examples. The measurement method and evaluation method in the examples were as follows.

(a) Measurement of monomer unit content in resin The measurement was carried out by the following method using a salted-out dried resin of vinylidene chloride resin latex.

It was calculated by subtracting the total from 100.

The content of various vinyl monomers is It depends on the preparation ratio of Kintoki.

(b) Impregnation method: Add and mix a specified amount of aluminum hydroxide into vinylidene chloride resin latex, and add an alkali thickener (Nippon Acrylic Chemical "Primal ASE-60") to 70c.
After adjusting the viscosity to p (B-type viscometer BL rotor 12 rpm, 2Q°C), the nonwoven fabric was impregnated by dipping, squeezed with a mangle, and dried at 120°C for 3 minutes.

(c) Coating method: Add and mix a specified amount of aluminum hydroxide into vinylidene chloride resin latex, and apply 1 coat using Primal ASE-60.
0,000 cp (B type viscometer 40-ter 12rps
+20°C) to prepare a compound. The compound is coated with the Warner Matisse coating equipment LTF/
SV type” (doctor knife method), 120
It was dried at ℃ for 3 minutes.

(d) Flame retardancy evaluation method The flame retardance of the nonwoven fabric was evaluated in accordance with the JIS-D-1201-1977 combustion test method and flame retardant test method, and was expressed in the following categories.

Comparisons in the margins below: Easy flammability: Burning speed exceeding 100 mm / 7 minutes Delayed flammability: Burning speed of 100+ mm / minute removal Self-extinguishing 2 Self-extinguishing properties Flame retardant, with a flame retardant index of over 30 Grade 2: Flame retardant with a flame retardant index of over 27 and below 30 Grade 3 flame retardant: Flame retardant index of 24
Flame retardant grade 4: flame retardant index greater than 21 and 27 or less
4 or less (e) High-frequency adhesive evaluation method Pearl Industries - "High-frequency welder R/203D type J
(3Kw/40.46M) Iz) was used to weld the composite using the non-woven fabric, and the adhesive strength was measured using Toyo Baldwin ``Tensilon Tensile Tester Model UTM-4L''.

Welding conditions: Tuning dial 80℃ Part electrode (mold) shape 4m thickness x 200B width Electrode temperature 30℃ (room temperature) Tensile conditions: Sample effective length 40 cranes x medium 25 cranes Tensile speed 50 cranes/min 1180 degree peeling (to) Texture The texture of the nonwoven fabric was evaluated by the feel of the hand and expressed based on the following criteria.

0: Almost as good as the original fabric △: Slightly hard but still practical ×: Hard and cannot be put to practical use Note that all weight % and weight parts in the examples are expressed in dry solid weight. In addition, each monomer unit was expressed using the following abbreviations.

VDC: Vinylidene chloride AN: Acrylonitrile BA: n-butyl acrylate 2EHA: 2-ethylhexyl acrylate HEA
: 2-Hydroxyethyl acrylate AA Niacrylic acid NP-A : Neopentyl glycol diacrylate Example 1 A nylon spunbond nonwoven fabric (Asahi Kasei Kogyo ``IEL 104ONJ'') with a basis weight of ii 40 g/rrr was used as the raw fabric.VDC/AN/BA /HHA Near 5/10
/14/1 (wt%) of vinylidene chloride resin latex and aluminum hydroxide (Showa Light Metal "Hisilite H-42MJ") with an average particle size of 1 μm in various ratios were impregnated into a nonwoven fabric and dried. The flame retardancy and texture of the nonwoven fabric were evaluated.
Thick vinyl chloride leather/10 mm thick flexible polyurethane foam (density 16 g/J)/Non-woven fabrics were layered together and high-frequency bonded (press pressure 20 kf/c IIG, current applied for 8 seconds), and adhesive strength was measured by sandwiching the chloride leather and non-woven fabric. The results are shown in Table 1.

As shown in Table 1 below, the nonwoven fabric G of the present invention exhibited excellent self-extinguishing properties and high-frequency adhesive properties, and had a good texture. Nonwoven fabric B, in which the amount of mixture impregnated (adhesive amount) was less than 25 parts by weight, had insufficient flame retardancy and high-frequency adhesion, and nonwoven fabric C, in which the amount of mixture impregnated (adhered amount) exceeded 100 parts by weight, had a significantly impaired feel. Nonwoven fabrics in which the resin solid content of vinylidene chloride resin latex in the mixture composition was less than 25% by weight lacked high frequency adhesion, and nonwoven fabrics E in which the resin solid content of vinylidene chloride resin latex exceeded 70% by weight had poor flame retardancy and texture. Nonwoven fabrics B and D with high circumference adhesive strength of 0,
When the high frequency application time (current application time) was extended in F, sparks were generated in all composites.

Furthermore, in nonwoven fabric A of the present invention, when the average particle size of aluminum hydroxide was changed to 60 μm, both flame retardancy and high frequency adhesiveness were significantly reduced, making it unusable for practical use.

Example 2 A polyester spunbond nonwoven fabric (Asahi Kasei Kogyo "IEL 100EJ") with a mesh size of 7rrr was used as the original fabric.The resin solid content of each vinylidene chloride resin latex consisting of the resin components shown in Table 2 was 60% by weight and the average A mixture consisting of 40% by weight of aluminum hydroxide (Showa Light Metal "Heijirai I-H-32J") with particles of 3.5 μm was applied in an amount of 65 parts by weight to 100 parts by weight of the original nonwoven fabric on one side and dried. The flame retardance and texture of the material were evaluated.Furthermore, starting from the surface, a 5-thick soft polyurethane foam (density 16 g/l) impregnated with 3 g/l of non-woven vinylidene mechloride resin latex (Asahi Kasei rL-502J) was evaluated.
)/Nonwoven fabrics are layered and high frequency bonded (press pressure 20kg/a
aG, current was applied for 6 seconds), and the adhesive strength was measured by sandwiching the nonwoven fabrics on the front and back sides of the composite.

As shown in Table 2, the nonwoven fabric G of the present invention exhibited excellent self-extinguishing properties, high-frequency adhesive properties, and texture.

Nonwoven fabrics H in which the vinylidene chloride unit content in the vinylidene chloride resin latex does not reach 50% by weight lack flame retardancy and high frequency adhesion, while nonwoven fabrics I in which the vinylidene chloride unit content exceeds 85% by weight
The texture of the nonwoven fabric ■ was determined to be X due to the crystallinity of the vinylidene chloride resin, and it was determined that the nonwoven fabric had extremely poor light discoloration resistance and was not suitable for practical use.Acrylonitrile unit content Non-woven fabric J with less than 2% by weight has no self-extinguishing properties, and non-woven fabric with more than 25% by weight significantly impairs high-frequency adhesion and texture, making it impractical in terms of color fastness and film-forming properties. In addition, the coating films of nonwoven fabrics H and J were highly sticky, and processing workability was considered to be reduced.

Example 3 Artificial leather made of wet-laid polyester non-woven fabric with a basis weight of 230 g/rrf (Asahi Kasei Kogyo ``Lamous'') was used as a raw fabric. VDC/BA: 80/20 (wt%) and VD
C/AN/2EHA: 25/40/35 (weight %) and each vinylidene chloride resin latex were blended at a dry solid content of 85/15 (weight ratio). A mixture shown below was prepared using the blended latex, and 10 sheets of raw material were prepared.
A nonwoven fabric M of the present invention was obtained by applying 50 parts by weight to the back surface of the nonwoven fabric M, and its flame retardant texture was evaluated. Furthermore, from the surface, 3N thick soft polyurethane foam (density 16 g/l)/vinylidene chloride resin latex (Asahi Kasei rL-501J) impregnated with 10 g/l of nonwoven fabric/vinylidene chloride resin latex (Asahi Kasei rL-5024) were added. 50
g/paint-resistant hardboards were stacked and high-frequency bonded (press pressure 55kg/cd G, energization 15 seconds), and the adhesive strength was measured by sandwiching the nonwoven fabric and hardboard.

Mixture: Vinylidene chloride resin latex (blended product) 4
5% by weight Aluminum hydroxide (Showa Light Metal Co., Ltd. “Hitulite 42MJ)” 45% by weight Antimony pentoxide (Nichijo Kagaku “Anzenzol A-155
0'') 10% by weight The results are shown in Table 3.

Table 3 As seen in Table 3, the nonwoven fabric M of the present invention exhibited excellent self-extinguishing properties, high-frequency adhesive properties, and texture.

〔Effect of the invention〕

The nonwoven fabric of the present invention is excellent in the following points.

(1) It has excellent self-extinguishing properties, high-frequency adhesion, texture, and light discoloration resistance, and is non-sticky on the surface.

(2) It is supplied at low cost and has excellent workability.

(3) It is particularly useful in fields that require high flame retardancy and suitability for high-frequency processing, such as interior materials for automobiles, vehicles, and buildings and insulating materials for electrical equipment.

(4) It has a wide range of applications and can be applied to many types of composite materials.

Procedural amendment (voluntary) September 77, 1985

Claims (1)

[Claims] 1. Resin component having the following composition: Resin solid content of vinylidene chloride resin latex consisting of 50 to 85% by weight of vinylidene chloride units, 2 to 25% by weight of acrylonitrile units, and 45% by weight or less of vinyl monomer units. A mixture formed of 25 to 70% by weight and 30 to 75% by weight of an inorganic water-containing compound with an average particle size of 20 μm or less is 25 to 10 parts by dry weight per 100 parts by weight of the raw nonwoven fabric.
Self-extinguishing nonwoven fabric with 0 parts by weight attached.