JP2003251767A - Polyolefin cross sheet for reinforcing nonwoven fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyolefin cloth sheet for reinforcing a nonwoven fabric which has excellent mechanical strength, does not generate toxic gas at the time of incineration, and has no ash residue and flame retardancy. SOLUTION: This is a cross sheet formed by weaving and knitting using a drawn polyolefin yarn as a weft yarn to be laminated on a polyolefin nonwoven fabric, wherein the polyolefin of the cross sheet comprises a nitrogen-containing compound represented by the following general formula (1). This is a polyolefin cloth sheet for reinforcing nonwoven fabric, which contains a flame retardant. H (R ₁₎ N over (CH _{2) a} chromatography N (R ₂₎ over (CH _{2) b} over N (R _{2 ')} over (CH _{2) c} over _{N (R 1) H (1} ) ( in the formula , R ₁ is a triazine derivative group containing a piperidyl group represented by the following general formula (2), R _{2 and} R _{2 ′} represent R ₁ or a hydrogen atom, and a, b and c each represent 2 to 5 Represents a positive number of.) (Wherein, R ₃ represents an alkyl group having 1 to 10 carbon atoms or a hydrogen atom, and R ₄ represents a carbon atom substituted with a cycloalkyl group having 5 to 10 carbon atoms or an alkyl group having 1 to 4 carbon atoms. Represents a cycloalkyl group having 5 to 10 atoms.)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin cloth sheet laminated and reinforced on a polyolefin nonwoven fabric.

[0002]

2. Description of the Related Art Polyolefin nonwoven fabrics are excellent in properties such as bulkiness, heat retention and air permeability, and are widely used for applications such as various kinds of covers, packaging materials, agricultural covering materials and civil engineering sheets. However, depending on the application, flame retardancy, tensile strength, tear strength, impact resistance, durability and the like are required. For this reason, surface heat woven using a multilayer flat yarn consisting of an outer layer of a low melting point component and an inner layer of a high melting point component, or a composite monofilament consisting of a sheath layer of a low melting point component and a core layer of a high melting point component as a weft yarn. A nonwoven fabric laminate (Japanese Utility Model Laid-Open No. 2-2125, etc.) has been proposed in which a fusible cloth sheet is used as a reinforcing material and laminated with a polyolefin nonwoven fabric by heat fusion. The cloth sheet generally contains a flame retardant such as a halogen-based flame retardant, a phosphorus-based flame retardant, and magnesium hydroxide in order to impart flame retardancy.

[0003]

However, the above-mentioned halogen-based flame retardants and phosphorus-based flame retardants not only generate toxic gas such as dioxin when incinerated, but also pose a problem of environmental pollution. There was a problem.
Therefore, in recent years, aluminum hydroxide has been used as a non-polluting flame retardant with no harmful gas generated during combustion and low smoke.
Various methods of adding a hydrate of an inorganic metal compound such as magnesium hydroxide (for example, Japanese Patent Application Laid-Open No. 2-53845) have been studied. However, there is no effect unless a large amount is added, and an inorganic flame retardant is used. Has a problem that ash is generated after incineration, causing troubles such as filter clogging. The present invention has been made in view of the above problems, and has excellent weather resistance and mechanical strength, does not generate a toxic gas during incineration, and has a nonflammable flame retardancy with no remaining ash. A sheet is provided.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the above object has been achieved by adding a small amount of a specific triazine derivative as a flame retardant. And completed the present invention. That is, the gist of the present invention is a cross-sheet formed by weaving and knitting a polyolefin stretched yarn laminated on a polyolefin nonwoven fabric as a weft yarn, wherein the cross-sheet polyolefin has a nitrogen represented by the following general formula (1). Polyolefin cloth sheet for reinforcing nonwoven fabric, comprising a flame retardant comprising a compound,
Exists. H (R ₁₎ N over (CH _{2) a} chromatography N (R ₂₎ over (CH _{2) b} over N (R _{2 ')} over (CH _{2) c} over _{N (R 1) H (1} ) ( in the formula , R ₁ is a triazine derivative group containing a piperidyl group represented by the following general formula (2), R _{2 and} R _{2 ′} represent R ₁ or a hydrogen atom, and a, b and c each represent 2 to 5 Represents a positive number of.)

Embedded image (Wherein, R ₃ represents an alkyl group having 1 to 10 carbon atoms or a hydrogen atom, and R ₄ represents a carbon atom substituted with a cycloalkyl group having 5 to 10 carbon atoms or an alkyl group having 1 to 4 carbon atoms. Represents a cycloalkyl group having 5 to 10 atoms.)

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The cross sheet according to the present invention includes:
As long as a low melting point polyolefin is used as the surface layer, the warp yarn is not limited to a single layer structure, and may be used in a multilayer structure. The multilayer structure has a structure in which a low-melting-point polyolefin is used as an outer layer and a high-melting-point polyolefin is used as an inner layer. The low-melting-point polyolefin is determined by a combination with a high-melting-point polyolefin, and is at least 10 ° C., preferably 15 to 50 ° C. lower than the high-melting-point polyolefin, such as a high-melting-point polyolefin. When a propylene homopolymer is used, an ethylene-propylene block copolymer, an ethylene-propylene random copolymer or a polyethylene resin is used. Examples of the polyethylene resin include high-density polyethylene, linear low-density polyethylene, branched low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-alkyl acrylate copolymer, and the like. Melt flow rate of the above polyethylene resin (hereinafter referred to as MFR)
Is abbreviated as 0.1 to 50 g / 10 min, preferably 1 to 4 g
It is good to select from the range of 0 g / 10 min, more preferably from 5 to 30 g / 10 min.

On the other hand, as the high melting point polyolefin, for example, a polypropylene resin is used. Examples of the polypropylene resin include known polypropylene copolymers such as a propylene homopolymer, an ethylene-propylene block copolymer or a random copolymer or a mixture thereof, and among them, high strength and heat resistance A propylene homopolymer is desirable. The polypropylene resin has a melt flow rate (hereinafter abbreviated as MFR) of 0.1 to 50 g / 10 min, preferably 1 to 40 g.
g / 10 minutes, more preferably in the range of 5 to 30 g / 10 minutes.

[0007] The form of the composite having the multilayer structure is a multilayer polyolefin flat yarn comprising an outer layer of a low-melting polyolefin and an inner layer of a high-melting polyolefin, or a sheath layer of a low-melting polyolefin and a core layer of a high-melting polyolefin. And a multi-layer structure thereof, for example, as a warp yarn, an ethylene-propylene random copolymer layer / a polypropylene homopolymer layer / an ethylene-propylene random copolymer layer. Composite, composite of branched low-density polyethylene layer / high-density polyethylene layer / branched low-density polyethylene layer, composite of linear low-density polyethylene layer / high-density polyethylene layer / linear low-density polyethylene layer, etc. Is mentioned.

In the present invention, a nitrogen-containing compound represented by the following general formula (1) is used as a flame retardant blended in the above-mentioned polyolefin. H (R ₁₎ N over (CH _{2) a} chromatography N (R ₂₎ over (CH _{2) b} over N (R _{2 ')} over (CH _{2) c} over _{N (R 1) H (1} ) ( in the formula , R ₁ is a triazine derivative group containing a piperidyl group represented by the following general formula (2), R _{2 and} R _{2 ′} represent R ₁ or a hydrogen atom, and a, b and c each represent 2 to 5
Represents a positive number. )

Embedded image (Wherein, R ₃ represents an alkyl group having 1 to 10 carbon atoms or a hydrogen atom, and R ₄ represents a carbon atom substituted with a cycloalkyl group having 5 to 10 carbon atoms or an alkyl group having 1 to 4 carbon atoms. Represents a cycloalkyl group having 5 to 10 atoms.)

As the nitrogen-containing compound represented by the general formula (1), a nitrogen-containing compound represented by the following general formula (3) is preferable, and particularly, a combination of the following general formula (3) and the following general formula (4) Is preferred. H (R ₁₎ N over (CH _{2) 3} over N (R ₁₎ over (CH _{2) 2} over NH chromatography (CH _{2) 3} over N (R ₁₎ H (3) In other words, the general formula (3) In the general formula (1), R ₁ is a triazine derivative group containing a piperidyl group represented by the general formula (2),
R ₂ is R ₁ , R _{2 ′} is a hydrogen atom, and a, b and c are nitrogen-containing compounds having positive numbers of 3, 2, and 3, respectively.

Embedded image The one represented by the general formula (4) is
It represents R ₁ of (1) or (3), and is represented by the general formula (2)
Is a triazine derivative group containing a piperidyl group in which R ₃ is a butyl group having 4 carbon atoms and R ₄ is a cyclohexyl group having 6 carbon atoms.

In the present invention, as a specific example, in the case of a composite monofilament, a desired amount of the above-described flame retardant is blended with each of the polyolefins of the core layer and the sheath layer, and the mixture is melt-kneaded and used. The compounding ratio of the flame retardant is 0.1 to 5 with respect to the total weight of the polyolefin.
%, Preferably in the range of 0.5-4% by weight. If the amount is less than the above range, the flame retardancy is insufficient, and if the amount exceeds the range, the effect of the flame retardancy is not further improved, which leads to an increase in cost.

The method for producing the composite monofilament is not particularly limited, and the composition of the polyolefin and the flame retardant in each layer of the above-mentioned combined resin is melt-kneaded by an extruder, and is melted at a melting temperature of 170 to 240 ° C. The core layer made of high-melting-point polyolefin is supplied from the center ejection hole of the die in which the discharge holes of the layer are provided substantially concentrically, and a sheath layer made of low-melting-point polyolefin is extruded on the outer surface to form a composite monofilament. , A stretching treatment or the like to obtain a composite monofilament. As the stretching process, a hot stretching method, that is, this hot stretching is a high melting point thermoplastic resin of the core layer, for example, the melting point of the polyolefin resin or less,
The temperature is equal to or higher than the softening point.
To 150 ° C., the stretching ratio is usually 3 to 15 times, preferably 5
~ 12 times.

The fineness of the formed composite polyolefin monofilament is 200 to 3000 dtex (hereinafter referred to as dt).
), Preferably in the range of 300 to 2000 dt. If the fineness is less than 200 dt, the strength is insufficient, and if it exceeds 3000 dt, the flexibility is inferior.

As the cross sheet of the present invention, a woven or knitted fabric is formed by weaving the drawn yarn of the composite monofilament as a warp yarn. The structure of the woven or knitted fabric is not particularly limited, and the woven fabric includes, for example, plain weave, twill weave, mosaic weave, rou weave, and entangled weave. No. The driving density of the warp yarn is 1 to 10 yarns / 2.54 c.
m, preferably in the range of 2 to 7 / 2.54 cm,
If the density is lower than the lower limit, the reinforcing effect is insufficient, and if the density is higher than the upper limit, the air permeability of the nonwoven fabric is deteriorated. The mesh interval of the woven or knitted fabric is 1 to 50 mm, preferably 3 to 30 m.
m.

The cross sheet of the present invention may be composed of a single-layer flat yarn as a weft yarn, a single-layer flat yarn as one of the weft yarns, a multi-layer flat yarn as the other weft yarn, and a multi-layer flat yarn as the weft yarn. Examples include those using a yarn, those using a composite monofilament as the weft, those using a multilayer flat yarn on one of the warp yarns, and using the composite monofilament on the other.

In the present invention, the polyolefin nonwoven fabric reinforced laminated sheet is obtained by laminating the polyolefin cloth sheet obtained above on at least one surface of the polyolefin nonwoven fabric. As a lamination method, an extrusion lamination method, a dry lamination method, a thermocompression lamination method, or the like can be used. Examples of the polyolefin nonwoven fabric include a melt-blowing method in which fibrous materials melt-extruded using polyolefin are randomly stacked, and the fibrous materials in a molten state are melt-bonded to form a sheet, or the cooled fibrous materials are heated together. Any of a spun bond method in which a sheet is formed by melting and bonding with an embossing roll can be used. As the polyolefin used to form the nonwoven fabric, high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-alkyl acrylate copolymer and the like Any of polyethylene-based resin, polypropylene-based resin such as polypropylene, propylene-ethylene block or random copolymer, and the like have good adhesion to the cloth and are preferably used.

Further, the polyolefin nonwoven fabric reinforced laminated sheet obtained as described above is often used outdoors, and is required to have high weather resistance because it is exposed to sunlight for a long period of time. The flame retardant used in the present invention is a triazine derivative having a piperidyl group, and itself functions as a hindered amine light stabilizer, and therefore has extremely high weather resistance. Furthermore, as a method for improving the weather resistance, a method of adding a weather agent such as an ultraviolet absorber or a light stabilizer can also be adopted.

As specific examples of the ultraviolet absorber, specifically, 2-ethylhexyl-2-cyano-3,3'-diphenyl acrylate, ethyl-2-cyano-3,3'-diphenyl acrylate, octyl-2- Cyanoacrylate-based ultraviolet absorbers such as cyano-3,3'-diphenylacrylate; benzophenone-based ultraviolet absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, and 2-hydroxy-4-octoxybenzophenone 2,2- (2'-hydroxy-5'-methylphenyl)
Benzotriazole UV absorbers such as benzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole, resorcinol monobenzoate, 2,4-di-t-butylphenyl-3'-5 ' And benzoate-based ultraviolet absorbers such as -di-t-butyl-4'-hydroxybenzoate.

As hindered amine light stabilizers, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1, 2,3,4-butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) di (tridecyl) -1,2,3,4-butanetetracarboxylate, 1- (2-hydroxyethyl) -2,2,
And polycondensates of 6,6-tetramethyl-4-piperidinol and diethyl succinate.

The polyolefin of the present invention contains an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, a pigment, an inorganic filler, without departing from the spirit of the present invention.
Additives such as a flame retardant, a cross-linking agent, a foaming agent, and a nucleating agent can be used in combination.

[0020]

Example 1 First, a polypropylene (MFR = 3.0 g /
(10 minutes, density = 0.90 g / cm ³ , Tm = 164 ° C.)
Then, 2% by weight of a flame retardant comprising a nitrogen-containing compound obtained by combining the compounds represented by the above general formulas (3) and (4) was blended, and a composition melt-kneaded at 200 ° C. was used. on the other hand,
For the sheath layer, a propylene-ethylene random copolymer (M
FR = 7.0 g / 10 min, density = 0.90 g / cm ³ , T
m = 130 ° C.), and 2% by weight of a flame retardant comprising a nitrogen-containing compound obtained by combining the compounds represented by the above general formulas (3) and (4), and melt-kneaded at 200 ° C. Was. Next, the composite monofilament extrudes the polypropylene of the core layer and the propylene-ethylene random copolymer of the sheath layer from a monofilament forming die in which two layers of discharge holes connected to two extruders are provided concentrically, and the stretching temperature is increased. The film was drawn at 120 ° C. and a draw ratio of 6.5 times, and annealed at a processing temperature of 140 ° C. to form a composite monofilament. The fineness of the obtained composite polyolefin monofilament is such that the core layer / sheath layer is 450 dt / 200 dt.
The total fineness was 650 dt. Using the composite monofilament thus obtained as a warp yarn, a driving density of 5 × 5
After plain weaving at 2.54 cm, the fabric was perforated to produce a woven fabric having a basis weight of 26 g / m ² . On one side of the woven fabric thus obtained, a spunbond nonwoven fabric made of polypropylene was laminated by thermocompression bonding. This laminate had good adhesiveness between the woven fabric and the nonwoven fabric, and the heat shrinkage of the laminate after heat treatment at 135 ° C. was as good as 4% vertical and 2% horizontal. In the flame retardancy test, the carbonization length was 50 mm or less in the combustion test according to JISA1322, and it passed the first class of flame prevention.

Comparative Example 1 In Example 1, the flame retardant was changed to melamine cyanurate (trade name: MC-610, manufactured by Nissan Chemical Co., Ltd.), and the above resin was added to 100 parts by weight of each of the core layer and the sheath layer. The same procedure was performed except that 10 parts by weight of melamine cyanurate was added. As a result, in the combustion test of the obtained laminate, the carbonization length was 150 mm or more, and it did not pass the flameproof first class of JISA1322. In addition, the compounding amount of melamine cyanurate necessary to pass the above flameproofing standard is 30 parts by weight based on 100 parts by weight of each of the polypropylene of the core layer and the sheath layer, and the flame retardant used in the present invention is: It has been found that a satisfactory flame retardant effect cannot be obtained unless a large amount is added, as compared with a sufficient effect when only 2% by weight is added.

Comparative Example 2 In Example 1, the flame retardant was changed to a mixture of the brominated flame retardant decabrom diphenyl ether and antimony trioxide at a ratio of 3: 1. The same procedure was performed except that 10 parts by weight of the above-mentioned brominated flame retardant was blended. As a result, in the combustion test of the obtained laminate, the JIS A1
It failed the flame retardant class 322.

Comparative Example 3 In Example 1, the flame retardant was changed to ammonium triphosphate, and 1 part by weight was added to 100 parts by weight of the polyethylene.
The same procedure was performed except that 0 parts by weight were blended. As a result, in the flame retardancy test of the obtained laminate, the carbonized length was 150 mm or more, and the laminate did not pass the first class flameproofing of JISA1322.

[0024]

As described above, the present invention relates to a cross sheet made of a woven or knitted fabric using a drawn polyolefin yarn to be laminated on a polyolefin nonwoven fabric, wherein the polyolefin of the cross sheet is represented by the following general formula (1): It contains a flame retardant consisting of a nitrogen-containing compound represented by the formula, and has no danger of generating toxic gas unlike halogen-based flame retardants and phosphorus-based flame retardants, and burns like inorganic flame retardants By blending a small amount without the possibility of remaining ash, a polyolefin nonwoven reinforced laminated sheet excellent in weather resistance, mechanical strength, and flame retardancy can be provided.

Continuation of front page    F term (reference) 4F100 AH03B AH03H AK03A AK03B                       AK07 AL05B CA08 DG04B                       DG11B DG15A DG20B EC03                       EC032 EH17 EH172 EJ37                       EJ372 EJ38B GB01 GB07                       GB15 JJ07 JK01 JL09 YY00B                 4J002 BB001 BB031 BB061 BB071                       BB121 BB151 BP021 EU086                       EU186 FD136 GA00 GF00                       GG02 GK01 GL00

Claims (5)

[Claims] 1. A cross sheet formed by weaving and knitting a drawn polyolefin yarn to be laminated on a polyolefin nonwoven fabric as a warp yarn, wherein the polyolefin of the cross sheet comprises a nitrogen-containing compound represented by the following general formula (1): A polyolefin cloth sheet for reinforcing nonwoven fabric, comprising a flame retardant. H (R ₁₎ N over (CH _{2) a} chromatography N (R ₂₎ over (CH _{2) b} over N (R _{2 ')} over (CH _{2) c} over _{N (R 1) H (1} ) ( in the formula , R ₁ is a triazine derivative group containing a piperidyl group represented by the following general formula (2), R _{2 and} R _{2 ′} represent R ₁ or a hydrogen atom, and a, b and c each represent 2 to 5 Represents a positive number of.) (Wherein, R ₃ represents an alkyl group having 1 to 10 carbon atoms or a hydrogen atom, and R ₄ represents a carbon atom substituted with a cycloalkyl group having 5 to 10 carbon atoms or an alkyl group having 1 to 4 carbon atoms. Represents a cycloalkyl group having 5 to 10 atoms.) 2. The polyolefin cloth sheet for reinforcing nonwoven fabric according to claim 1, wherein the compounding amount of the flame retardant is in the range of 0.1 to 5% by weight based on the polyolefin. 3. The polyolefin cloth sheet for reinforcing nonwoven fabric according to claim 1, wherein the drawn polyolefin yarn is a multilayer flat yarn having a low melting point polyolefin as an outer layer and a high melting point polyolefin as an inner layer. 4. The nonwoven fabric reinforcing polyolefin cloth sheet according to claim 1, wherein the drawn polyolefin yarn is a composite monofilament having a low-melting-point polyolefin as a sheath layer and a high-melting-point polyolefin as a core layer. 5. The polyolefin cloth sheet for reinforcing a nonwoven fabric having light transmittance according to claim 1, wherein the flame retardant is a nitrogen-containing compound represented by the following general formula (3). H (R ₁₎ N over (CH _{2) 3} over N (R ₁₎ over (CH _{2) 2} over NH chromatography (CH _{2) 3} over _{N (R 1) H (3} ) ( wherein, R ₁ is the following It is a triazine derivative group containing a piperidyl group represented by the general formula (4).)