JP5025174B2 - Flame retardant resin composition and electric wire and cable using the same - Google Patents

Description

The present invention eliminates the generation of toxic gases such as halogen gas during combustion, is excellent in flame retardancy and mechanical properties, and is easy to cut (terminal cutting treatment), particularly in the insulation layer and sheath layer of electric wires and cables. The present invention relates to a flame retardant resin composition that is suitably used, and an electric wire or cable using the flame retardant resin composition.

  Conventionally, a polyvinyl chloride resin composition has been used as a flame retardant material such as a wire covering material. However, since the polyvinyl chloride resin composition generates a toxic halogen-containing gas when combusted, improvement has been demanded. In order to overcome the above disadvantages of polyvinyl chloride resin, a resin composition (non-halogen flame retardant material) in which a metal hydrate such as magnesium hydroxide is blended with a thermoplastic resin such as a polyolefin resin or a thermoplastic elastomer has been proposed. (For example, refer to Patent Document 1).

  In such a resin composition, in order to impart flame retardancy to a polyolefin-based resin or the like, metal hydrate is generally the same as the resin component in the composition, depending on the required level of flame retardancy. The amount needs to be added to a high concentration. For this reason, in order to achieve a high flame retardant level, the amount of the matrix resin must be reduced, and as a result, there is a conflicting problem that mechanical properties depending on the physical properties of the resin are lowered. In order to overcome such problems, it has been recently studied to maintain both physical properties of flame retardancy and mechanical properties. For example, a resin having high flame retardancy and good mechanical properties, in which 40 to 300 parts by weight of a metal hydrate having a small average particle diameter treated with a silane coupling agent is blended with 100 parts by weight of an olefin polymer. A composition (see, for example, Patent Document 2) has been proposed. However, this method has good mechanical properties including tensile impact strength. However, in the case of electric wires and cables coated with the resin composition, the core wire to be used during wiring construction is crimped or soldered to various connectors, etc. In the terminal treatment, there remains a problem that it is difficult to peel off the coating layer or the insulating layer from the core wire with a jig or the like (also referred to as terminal cutting treatment).

  Also, a resin composition containing 60 to 200 parts by weight of a metal hydrate having a large specific surface area to which 1 to 25% of a high degree of polymerization polyorganosiloxane is added to 100 parts by weight of a polyolefin-based resin (for example, patent document) 3) is proposed. This is because the flame retardancy is improved by using a metal hydrate with a large specific surface area, so flame retardancy and extrudability, appearance of molded products, tensile properties, flexibility, etc. are reduced by reducing the amount added to the resin. However, it is estimated that the tensile strength is high because the mechanical properties are improved by relatively increasing the amount of matrix resin in this method. There are still problems that are difficult to do.

  On the other hand, as a method for solving easy cutability (terminal cutting treatment), in addition to an ethylene polymer, a functional group-containing olefin polymer, and an inorganic flame retardant, a soft material and / or a liquid emulsifier is blended to make it flexible and tensile. A method of obtaining a resin composition having low impact strength and easy cutting properties (see, for example, Patent Document 4), in addition to an ethylene polymer, a functional group-containing olefin polymer, and an inorganic flame retardant, having a specific density A method of obtaining a resin composition having a low tensile impact strength and good cutability by blending a polyethylene resin (for example, see Patent Document 5) has been proposed.

However, a resin composition in which a metal hydrate such as magnesium hydroxide is blended with a polyolefin resin or a resin composition in which a functional group-containing olefin polymer is further blended with the above composition is easier than a polyvinyl chloride resin. Cutability is inferior. Easy cutability can be improved by increasing the amount of metal hydroxide added, but at the same time, physical properties such as a decrease in tensile strength and damage resistance have been reduced, and a product with a good overall balance has not been obtained. . Further, the poor cutability has an adverse effect on workability when stripping the coating material during the on-site construction of the electric wire and on the appearance after the construction.
Japanese Unexamined Patent Publication No. 7-149965 JP 2005-139388 A JP 2005-179409 A JP 2005-29604 A JP 2005-29605 A

The object of the present invention is to overcome the disadvantages of flame retardant thermoplastic resin compositions such as polyolefin resin compositions and thermoplastic elastomers containing metal hydrates, in view of the above-mentioned conventional problems, such as tensile strength. An object of the present invention is to provide a flame retardant resin composition excellent in the balance of various properties such as easy cut performance, flame retardancy and mechanical properties as well as physical properties, and an electric wire or cable using the same.

  As a result of diligent research to solve the above problems, the present inventors have found that a thermoplastic resin, preferably a polyolefin resin and / or a thermoplastic elastomer, have primary particles having an average particle diameter in a specific range, and further, Resin composition containing a specific amount of metal hydrate containing secondary particles composed of aggregates formed in an aggregate structure and having a large specific surface area, as well as mechanical properties such as tensile strength The present invention has been completed by finding that it can be a flame retardant resin composition having an excellent balance of various properties such as easy cut performance and flame retardancy.

That is, according to the first invention of the present invention, (A) 100 parts by mass of a thermoplastic resin and (B) a metal hydrate that satisfies the following conditions (a) to (c) (B1) water A flame retardant resin composition comprising 30 to 250 parts by mass of magnesium oxide is provided.
(B) The average particle size calculated based on the volume-based particle size distribution measured by a laser beam diffraction / scattering particle size distribution measuring device is in the range of 1 to 10 μm. (B) Form by scanning electron microscope From the photograph, it was observed that secondary particles composed of aggregates formed of primary particles were included, and the length average particle diameter based on the number-based particle size distribution in the major axis direction of the primary particles measured from the morphological photograph was 0. .01-0.5 [mu] m and 5 [mu] m or more particles are 0.1% or less (c) Specific surface area by BET method is 8.0 m < ² > / g or more.

According to the second invention of the present invention, there is provided a flame retardant resin composition according to the first invention, wherein (B) the metal hydrate further satisfies the following condition (d): Provided.
(D) The ratio of the average particle diameter measured by a laser light diffraction / scattering particle size distribution measuring instrument to the average particle diameter of primary particles measured from a morphological photograph by a scanning electron microscope is 5 or more.

According to a third aspect of the present invention, there is provided a flame retardant resin composition according to the first aspect , wherein (B1) magnesium hydroxide is produced by a synthesis method. .

According to the fourth invention of the present invention, in the third invention, (B1) the magnesium hydroxide obtained by the synthesis method is obtained by adding an alkaline substance to an aqueous solution containing a magnesium salt, or magnesium oxide is water. A flame retardant resin composition characterized by being obtained by adding together is provided.

According to a fifth invention of the present invention, in any one of the first to fourth inventions, (A) the thermoplastic resin is a resin containing (A1) a polyolefin-based resin and / or (A2) a thermoplastic elastomer. A flame retardant resin composition is provided.

According to a sixth invention of the present invention, in the fifth invention, (A) the thermoplastic resin comprises an ethylene / unsaturated carboxylic acid ester copolymer, an ethylene / vinyl ester copolymer, and a density of 0. (A1) 100-20% by mass of a polyolefin resin and (A2) a thermoplastic elastomer which is at least one ethylene copolymer selected from ethylene / α-olefin copolymers of .86 to 0.94 g / cm ³ Provided is a flame retardant resin composition, which is a resin containing 0 to 80% by mass.

According to the seventh invention of the present invention, in any one of the first to sixth inventions, (C) the functional group-containing polyolefin resin is further added to 1 to 30% by mass (provided that (A) the thermoplastic resin. A flame retardant resin composition is provided that includes (A) component and (C) component are 100% by mass in total).

According to an eighth aspect of the present invention, there is provided an electric wire or cable using the flame retardant resin composition according to any one of the first to seventh aspects.

  The flame retardant resin composition of the present invention includes primary particles having an average particle diameter in a specific range, and secondary particles formed with an aggregate structure composed of primary particles, and has a feature that the specific surface area is large. By blending a specific amount of Japanese product, it retains various performances of conventional non-halogen flame retardant resin compositions, and has excellent performance such as high flame retardancy, easy cutability (terminal cutting treatment), and mechanical strength. It is a resin composition that can provide an electric wire / cable, and the electric wire and cable using the flame-retardant resin composition for an insulating layer and / or a sheath layer, etc. are excellent in the above-mentioned various performances, and can be used for product appearance and field construction. Easy cutability (end cutting treatment) is good and workability is excellent.

The present invention, (A) a thermoplastic resin, is preferably 100 parts by weight of the resin containing (A1) the polyolefin resin and / or (A2) a thermoplastic elastomer, (B) a metal hydrate (B1) hydroxide Flame retardant resin containing 30 to 250 parts by mass of magnesium and, if necessary, 1 to 30% by mass of (C) functional group-containing polyolefin resin (the total of (A) and (C) components is 100% by mass) It is an electric wire or cable using the composition and the flame retardant resin composition. Hereinafter, the present invention will be described in detail for each item.

1. Component of Flame Retardant Resin Composition (A) Thermoplastic Resin (A) The thermoplastic resin used in the flame retardant resin composition of the present invention is not particularly limited, but preferably (A1) polyolefin Resin and / or (A2) thermoplastic elastomer. Each component will be described below.

(A1) Polyolefin-based resin The (A1) polyolefin-based resin used in the present invention is a high-density polyethylene having a density of 0.94 to 0.97 g / cm ³ by ion polymerization, a density of less than 0.91 to 0.94 g / cm ^3. Ethylene / α-olefin copolymer (linear low density polyethylene), ethylene / α-olefin copolymer (ultra low density polyethylene) having a density of 0.86 to less than 0.91 g / cm ³ , high pressure radical polymerization Low density polyethylene by ethylene, ethylene copolymer of at least one monomer selected from ethylene and α, β-unsaturated carboxylic acid, α, β-unsaturated carboxylic acid ester, vinyl ester, polypropylene resin, etc. At least one polyolefin-based resin selected from the group consisting of:
Among these polyolefin resins, the details will be described below. (A1) Ethylene / α, β-unsaturated carboxylic acid ester copolymer, (a2) Ethylene / vinyl ester copolymer, (a3) Density 0.86 An ethylene / α-olefin copolymer of less than ˜0.94 g / cm ³ is preferred because of its excellent acceptability of the component (B) metal hydrate.
Here, the density is a value measured according to JIS K6922-1 (1997).

(A1) Ethylene / α, β-unsaturated carboxylic acid ester copolymer As a copolymer of ethylene and α, β-unsaturated carboxylic acid ester, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate Copolymer, Ethylene / butyl acrylate copolymer, Ethylene / methyl methacrylate copolymer, Ethylene / (meth) acrylic acid or its alkyl ester copolymer such as ethylene / ethyl methacrylate copolymer; Ethylene / anhydrous Maleic acid / vinyl acetate copolymer, ethylene / maleic anhydride / methyl acrylate copolymer, ethylene / maleic anhydride / ethyl acrylate copolymer binary copolymer or multi-component copolymer, or their A metal salt etc. are mentioned.
In the above copolymer, comonomer copolymerized with ethylene includes methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, acrylic acid -N-butyl, -n-butyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, lauryl acrylate, lauryl methacrylate and the like can be mentioned. Among these, alkyl esters such as methyl (meth) acrylate and ethyl (meth) acrylate are particularly preferable. In particular, the (meth) acrylic acid ester content is in the range of 3 to 30% by mass, preferably 5 to 20% by mass.
Examples of the metal salt include K, Na, Li, Ca, Zn, Mg, and Al.

(A2) Ethylene / vinyl ester copolymer As the ethylene / vinyl ester copolymer, ethylene produced by a high-pressure radical polymerization method, vinyl propionate, vinyl acetate, vinyl caproate, vinyl caprylate, vinyl laurate, Examples thereof include copolymers with vinyl ester monomers such as vinyl stearate and vinyl trifluoroacetate. Particularly preferable examples of these vinyl esters include vinyl acetate.
The proportion of ethylene and vinyl ester in the copolymer is 50 to 99.5% by mass of ethylene, 0.5 to 50% by mass of vinyl ester, and 0 to 49.5% by mass of other copolymerizable unsaturated monomers. A copolymer consisting of is preferred. Furthermore, the vinyl ester content is preferably selected in the range of 5 to 30% by mass, particularly preferably 10 to 25% by mass.

(A3) Ethylene / α-olefin copolymer The ethylene / α-olefin copolymer has a density of 0.86 to less than 0.91 g / cm ³ (linear ultra-low density polyethylene) and a density of 0.91. To less than 0.94 g / cm ³ (linear low density polyethylene), preferably in the range 0.88 to 0.91 g / cm ³ ethylene / α-olefin copolymer (linear ultra low density polyethylene) and A mixture thereof may be mentioned. The α-olefin has 3 to 20 carbon atoms, preferably 4 to 12 carbon atoms, and specifically includes propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-hexene, Examples include octene, 1-decene, 1-dodecene and the like.
The polyethylene resin (a3) according to the present invention may be a mixture of two or more kinds of polyethylene resins as long as the above conditions are satisfied.

The ethylene / α-olefin copolymer (a3) is a slurry method, a solution method, a gas phase method by ionic polymerization of a Ziegler catalyst, a Philips catalyst, a vanadium catalyst, a metallocene catalyst, etc. under high, medium and low pressure. It can be produced by a polymerization method such as a bulk method.
The polyethylene resin (a3) produced by the above ion polymerization is not particularly limited to the production catalyst and process, etc., and the book “Polyethylene Technology Reader” (edited by Kazuo Matsuura and Naotaka Mikami, Industry Research Committee 2001) P. 123-160, p. It can be produced by a method described in 163 to 196 or the like.

The melt mass flow rate (MFR) of the (A1) polyolefin resin is preferably 0.01 to 100 g / 10 minutes, more preferably 0.1 to 50 g / 10 minutes, and still more preferably 0.1 to 10 g / 10. Selected in the range of minutes.
Here, MFR is a value measured under condition D (temperature 190 ° C., load 21.18 N) in accordance with JIS K6922-1 (1997).

(A2) Thermoplastic elastomer (A2) The thermoplastic elastomer that can be used in the present invention includes various thermoplastic elastomers such as olefin elastomer, styrene elastomer, polyester elastomer, polyamide elastomer, polyurethane elastomer, and natural rubber. Natural or synthetic rubbers such as polyisobutylene, polyisoprene, chloroprene rubber, butyl rubber, and nitrile butyl rubber. Among these, olefin elastomers and styrene elastomers described in detail below are preferable.

Olefin Elastomer Examples of olefin elastomers include ethylene-propylene copolymer (EPR), ethylene-propylene-diene copolymer (EPDM), ethylene / 1-butene copolymer, and ethylene / 1-octene copolymer. Amorphous or microcrystalline ethylene / α-olefin copolymer having a density of 0.86 to 0.91 g / cm ³ , polybutene, chlorinated polyethylene, polypropylene and EPDM, and optionally polyethylene were crosslinked in the presence of a crosslinking agent. A partially crosslinked product or a completely crosslinked product is exemplified.

Styrene elastomers Styrene elastomers include block copolymers such as styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and styrene-isoprene-butadiene-styrene copolymer (SIBS). Polymer, or styrene-ethylene-butene-styrene copolymer (SEBS), styrene-ethylene-propylene-styrene copolymer (SEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer) A part of a block copolymer such as a polymer) or a completely hydrogenated product.

As the thermoplastic resin (A) of the present invention, polyolefin (A1) and / or thermoplastic elastomer can be preferably used. However, since a large amount of metal hydrate is blended, an acceptable amount thereof is ensured. In order to maintain the balance between flexibility and mechanical strength, it is also one of desirable modes that (A1) a polyolefin resin and (A2) a thermoplastic elastomer are used in combination. In particular, it is preferable to select the resins (a1) to (a3) of the component (A1).
These composition ratios are (A1) polyolefin resin, preferably 100-20% by mass, (A2) thermoplastic elastomer 0-80% by mass, more preferably (A1) 100-60% by mass, (A2 ) 0 to 40% by mass, particularly preferably (A1) 100 to 70% by mass and (A2) 0 to 30% by mass.
In the blend of (A1) and (A2), a composition having excellent flexibility is obtained when (A1) is less than 20% by mass and (A2) is more than 80% by mass. Further, in order to obtain a composition having a good balance of mechanical strength, flexibility, etc., the above-described more preferable blending ratio is achieved. These are appropriately selected according to the purpose.

(B) Metal hydrate (B) Metal hydrate used in the flame retardant resin composition of the present invention is (b) a volume-based particle size distribution measured by a laser light diffraction / scattering particle size distribution meter. The average particle diameter (arithmetic average diameter) calculated based on the above is in the range of 1 to 10 μm, and (b) secondary particles composed of aggregates formed of primary particles from a morphological photograph taken by a scanning electron microscope. It is observed that particles having a length average particle diameter in the range of 0.01 to 0.5 μm based on the number-based particle size distribution in the major axis direction of primary particles measured from morphological photographs and having a particle diameter of 5 μm or more are included. It satisfies the conditions that it is 0.1% or less, and (c) the specific surface area by the BET method is 8.0 m ² / g or more, and preferably (d) a laser light diffraction / scattering particle diameter Mean particle size measured by a distribution measuring instrument and scanning electron microscope The ratio between the average particle size of the measured primary particles Modes photograph is 5 or more by, and satisfies the. Each condition will be described in detail below.

The first requirement of the metal hydrate used in the present invention is (a) an average particle diameter (arithmetic average) calculated based on a volume-based particle diameter distribution measured by a laser light diffraction / scattering particle diameter distribution measuring device. The diameter) is in the range of 1 to 10 μm.
That is, the metal hydrate used in the present invention has an average particle diameter (arithmetic average diameter) of 1 to 10 μm calculated based on a volume-based particle size distribution measured by a laser light diffraction / scattering particle size distribution measuring device. It is essential that it has a range of 1 to 5 μm, preferably 1 to 5 μm, more preferably 1 to 3 μm, and still more preferably 99% or more of particles are in the range of 0.1 to 20 μm. It is desirable.
In the present invention, particles having an average particle diameter (arithmetic average diameter) in the range of 1 to 10 μm calculated based on the volume-based particle size distribution measured by a laser light diffraction / scattering particle size distribution meter are primary particles. It is represented by the arithmetic average diameter of a mixture of secondary particles and primary particles forming the aggregated structure, but the secondary particles composed essentially of the aggregated structure are mainly used.
When the average particle size is less than 1 μm, the mechanical properties are good, but the impact strength is improved, so that the easy-cut property which is the subject of the present invention may be lowered. On the other hand, if it exceeds 10 μm, the mechanical properties may be lowered.
The laser light diffraction / scattering particle size distribution measuring device is a method of irradiating a particle with laser light and analyzing the particle size distribution from the light intensity distribution of the diffracted / scattered light emitted from the particle, as described later. In general, a particle size distribution measuring apparatus using these principles is commercially available, and measurement can be performed by using these apparatuses.

The second requirement for the metal hydrate used in the present invention is that (b) from a morphological photograph taken by a scanning electron microscope, it is observed that secondary particles composed of aggregates formed from primary particles are included. The length average particle size based on the number-based particle size distribution in the major axis direction of the primary particles measured from the above is in the range of 0.01 to 0.5 μm, and the particles of 5 μm or more are 0.1% or less. Requirement.
That is, in the metal hydrate used in the present invention, the particles satisfying the average particle diameter of (a) are average length based on the number-based particle size distribution in the major axis direction measured from a morphological photograph by a scanning electron microscope. It is important to include secondary particles composed of aggregates formed from an aggregate structure of primary particles having a particle size in the range of 0.01 to 0.5 μm and particles of 5 μm or more being 0.1% or less. The average particle size is preferably in the range of 0.04 to 0.3 μm, more preferably 0.05 to 0.2 μm, and the primary particles of 3 μm or more are preferably 0.1% or less.
If the average particle size of the primary particles is less than 0.01 μm, mechanical properties such as tensile strength and elongation may decrease due to excessive aggregation, and the fluidity of the molten resin may decrease. If it exceeds 0.5 μm, there is a possibility that it is difficult to form an aggregated structure. If many primary particles with a coarse particle size are included, the mechanical properties and smoothness may be lowered. Therefore, the primary particles having a particle size of 5 μm or more should be 0.1% or less in the number-based particle size distribution. However, when expressed by a length reference particle size distribution, the primary particles of 5 μm or more are 5% or less, preferably 3 μm or more of primary particles are 5% or less.

The measurement method of the average length particle size based on the number-based particle size distribution in the major axis direction measured from a morphological photograph of primary particles by a scanning electron microscope is, for example, “Powder-Theory and Application-” edited by Teruichiro Kubo et al. (Second revised edition) pages 443-541 (Maruzen Co., Ltd .: issued on May 15, 1985), edited by Masafumi Arakawa et al. A well-known microscopy method outlined on the 15th) can be used. Specifically, a suitable primary image obtained from a morphological photograph with a magnification of about 2000 to 50000 times, preferably about 5000 to 30000 times by a scanning electron microscope, preferably a field emission type scanning electron microscope having higher resolution. The major axis is measured for about 200 to 1,000 particles, and the length average particle diameter is determined. Further, an amount containing a particle size of 5 μm or more is obtained from the integrated value of the number-based particle size distribution obtained by this method.
By the way, in measuring the particle size of non-uniform particles with a microscope, ferret diameter or biaxial average diameter is generally used. In the present invention, however, the crystal form is flat or hexagonal (hexagonal plate or Since there is a case of a metal hydrate having an elliptical plate shape with a corner, etc., a correlation with physical properties such as surface smoothness is obtained by using a value in the major axis direction of the plane instead of a flat minor axis direction. I thought. The number of particles to be measured is preferably several hundreds in the case of a sample having a uniform crystal form and about several thousand in the case of a sample having a non-uniform crushing form.

The third requirement of the metal hydrate used in the present invention, the BET specific surface area of (c) a metal hydrate, 8.0 m ² / g or more, preferably 8.0~50m ² / g, more Preferably it is 10-30 m < ² > / g. When the specific surface area by the BET method is 8.0 m ² / g or more, it is possible to obtain a flame retardant composition having good flame retardancy. On the other hand, if the specific surface area is too large, the fluidity at the time of melting of the flame retardant resin composition may be lowered when a large amount of metal hydrate is mixed. Accordingly, the specific surface area of the metal hydrate is desirably 50 m ² / g or less. By the way, it is presumed that there is a relative relationship between the particle diameter and the specific surface area. Generally, the finer the particles, the more the specific surface area tends to increase. Therefore, the particles (a) having an average particle diameter of 1 to 10 μm are ( B) It is not irrelevant to the fact that particles having an average particle size of 0.01 to 0.5 μm and particles of 5 μm or more are formed by the aggregation structure of fine primary particles of 0.1% or less, and as a result, good mechanical properties; It exhibits high flame retardancy as well as easy cutting.
Here, the measurement method of the specific surface area of the BET method is a method of calculating the specific surface area of the particles by the gas adsorption method, gas molecules having a known adsorption occupation area such as nitrogen gas adsorbed in advance to the particles, This is a method of calculating the specific surface area of particles from the amount of adsorption.
As a specific measurement method, for example, after performing a pretreatment such as deaeration of the sample (particles) at a predetermined temperature and a predetermined time using a fully automatic gas adsorption amount measuring apparatus, which will be described later, which is generally commercially available, Measured using an adsorbed gas such as nitrogen gas.

As the fourth requirement, the metal hydrate used in the present invention was further measured from (iv) an average particle diameter measured by a laser light diffraction / scattering particle size distribution measuring instrument and a morphological photograph taken by a scanning electron microscope. It is desirable that the ratio of the average particle size of the primary particles satisfies the requirement of 5 or more.
That is, the particles having an average particle diameter of 1 to 10 μm measured in (a) are represented by the arithmetic average diameter of the mixture of the secondary particles and the primary particles forming the primary particle aggregate structure as described above. Specifically, it can be easily observed by performing the above-described morphological observation that the secondary particles having an aggregated structure are the main particles.
Therefore, when this aggregate is expressed more quantitatively as an aggregate structure of primary particles, an aggregate structure of primary particles having an average particle diameter of 0.01 to 0.5 μm is formed, and an average particle diameter of 1 to 10 μm is substantially formed. Assuming that the particles are measured as secondary particles, it can be interpreted that the larger the ratio of the average particle diameter to the primary particles, the more aggregated.
In the present invention, it is desirable that the ratio (a) / (b) is 5 or more, preferably 10 or more and 50 or less, more preferably 15 or more and 40 or less.
If the ratio (b) / (b) is less than 5, the effect of easy cutting of the present invention may be small, and if it is 50 or more, a large amount of metal hydrate is mixed with the thermoplastic resin. There is a possibility that the fluidity at the time of melting of the flame retardant resin composition is lowered.
The metal hydrate of the present invention seems to be able to achieve the required physical properties in which mechanical strength and easy-cutting properties conflict with each other due to the presence of such an aggregate structure. In other words, the coexistence of the fine primary particles and the aggregates thereof cause the micro aggregates to break at the time of impact fracture while maintaining the mechanical strength and surface smoothness that are considered to be caused by the primary particles. It is assumed that easy cutability seems to be balanced at a high level.

In the present invention , (B) magnesium hydroxide satisfying the above (a) to (c), preferably (d) is used as the (B) metal hydrate. Magnesium hydroxide is most preferred from the viewpoint of thermal stability during molding. These are particularly preferably subjected to surface treatment.

The above-mentioned (B1) magnesium hydroxide retains the superiority of the present invention as long as it has the average particle size, specific surface area and aggregated structure which are the requirements of the above (a) to (c), more preferably (2). Therefore, the manufacturing method is not particularly limited. Therefore, it can be produced by a known method in the same manner as magnesium hydroxide generally used in flame retardant resin compositions.
In the present invention, those formed from mixed particles containing fine primary particles having an average particle diameter and secondary particles having an agglomerated structure formed from the primary particles have a high degree of mechanical strength and easy cutting properties. And a powder having a large specific surface area can be obtained.
As a method for producing these powders, the synthesis method is most preferable.

As this synthesis method, (i) a solution obtained by adding an alkaline substance to an aqueous solution containing a magnesium salt, more specifically, for example, magnesium chloride or magnesium nitrate is used as a magnesium salt, sodium hydroxide as an alkaline substance, A method for producing magnesium hydroxide by the action of aqueous ammonia, potassium hydroxide, calcium hydroxide or the like (see, for example, JP-A 61-168522, JP-A-2-229712, JP-A-7-97210) ), A method in which a small amount of sodium hydroxide is added to magnesium hydroxide and subjected to pressure heat treatment in an autoclave or the like (see, for example, Japanese Patent Publication No. 50-23680), and heat treatment in a basic magnesium salt aqueous medium. Method (for example, see Japanese Patent Application Laid-Open No. 52-115799) containing magnesium Magnesium chloride obtained by treating hydrochloric acid with natural minerals (eg, brucite, serpentine, dolomite, chlorite) or magnesium oxide contained in natural minerals (eg, magnesite) is leached with ammonium chloride. Using magnesium chloride obtained as a magnesium salt, for example, a method of reacting with calcium hydroxide to produce magnesium hydroxide through steps such as precipitation, washing, concentration, and drying (see, for example, JP-T-2001-508015), (Ii) Magnesium oxide obtained by hydration, more specifically, for example, magnesium oxide obtained by dissolving, purifying, and thermally decomposing a natural mineral containing magnesium, or natural mineral (for example, magnesium Oxide matrix obtained by firing magnesium carbonate produced as a site) Using Neshiumu, hydrating it, dried magnesium hydroxide obtained, and the like (e.g., Kokoku 3-60774, JP-A No. 5-208810, JP-see Japanese Patent Laid-Open No. 8-67515). Magnesium hydroxide synthesized by such a production method has a reaction pressure, a reaction temperature, a pH of an aqueous solution, a magnesium concentration, or a pulverization time in a fine pulverization process, a mill speed, etc. when a natural mineral is used in the production process. It is desirable from the viewpoint that the average particle diameter, the specific surface area, or the aggregated structure, which are the requirements of the above (a) to (c) and (d), can be easily obtained by appropriately controlling.
As another production method, (iii) a method of obtaining natural brucite as an aqueous slurry, wet-grinding, solid-liquid separation, and drying (see, for example, Japanese Patent Publication No. 7-42461), (iv) ) A method (for example, see JP-A No. 2000-202318) obtained by pulverizing coarsely ground brucite ore in a pulverizer.

  In addition, the magnesium hydroxide has a uniform primary particle size because the primary particles are not irregular in shape and have a crystal structure with flat crystals or flat hexagonal crystals. The dispersibility in the flammable composition is improved, and as a result, it is further preferable for improving various physical properties such as good mechanical properties, flame retardancy, and surface smoothness. Such a crystal structure can be confirmed by morphological observation using the scanning electron microscope or the like.

In addition, (B) the metal hydrate can be treated with a surface treatment agent to improve the dispersion effect in the thermoplastic resin, acid resistance, moisture absorption resistance, deactivation of metal active sites, and the like. preferable.
(D) Examples of the surface treatment agent include fatty acids and fatty acid metal salts or mixtures thereof, fatty acid esters, fatty acid amides, waxes or modified products thereof, curable resins, organic silanes, organic titanates, and organic boranes. In recent years, as disclosed in JP-A-2002-167219, JP-A-2002-173682, JP-A-2003-003167, JP-A-2004-337698, and the like, a polycarboxylic acid-based dispersion is used. Magnesium hydroxide surface-treated with an agent, polyglycerin derivative, N-acyl basic amino acid, or dibasic acid erythritol ester, phosphate ester, phosphite ester, alcohol phosphate ester, phosphorus compound, etc. is also used. Yes.
In the present invention, a combination with a fatty acid, a fatty acid metal salt or a mixture thereof, and a fatty acid ester is particularly preferable from the viewpoint of being inexpensive and effective, although not particularly limited thereto. These may be surface-treated in advance, or a resin component, magnesium hydroxide and the like may be mixed and used simultaneously.

  The fatty acid is preferably a saturated or unsaturated acid having 8 or more carbon atoms, octanoic acid, decanoic acid, myristic acid, behenic acid, palmitic acid, stearic acid, oleic acid, arachidic acid, coconut oil, beef tallow, large Examples include bean oil, palm oil, castor oil, and hardened oil.

  Examples of the fatty acid metal salt include metal salts such as stearic acid, oleic acid, palmitic acid, linoleic acid, lauric acid, caprylic acid, behenic acid, and montanic acid, and the metals include Na, K, Al, Ca, Mg, Zn, Ba, Co, Sn, Ti, Fe etc. are mentioned.

  As the fatty acid ester, methyl laurate, methyl myristate, methyl palmitate, methyl stearate, methyl oleate, methyl erucate, methyl behenate, butyl laurate, butyl stearate, isopropyl myristate, isopropyl palmitate, Monoesters such as octyl palmitate, octyl palmitate, octyl stearate, special beef tallow fatty acid octyl ester, lauryl laurate, stearyl stearate, long-chain fatty acid higher alcohol ester, behenyl behenate, cetyl myristate, etc. Neopentyl polyol long chain fatty acid ester, partially esterified product of neopentyl polyol long chain fatty acid ester, neopentyl polyol fatty acid ester, medium chain fat of neopentyl polyol Esters, neopentyl polyol C9 chain fatty acid esters, dipentaerythritol long chain fatty acid esters, special fatty acid esters such as complex medium chain fatty acid esters.

These surface treatment agents can be used in any treatment method such as a wet method or a dry method, but in the case of a wet method such as adding a surface treatment agent when forming magnesium hydroxide in an aqueous solvent, As a result of the efficient surface treatment of magnesium oxide, there is a concern that it is difficult to form aggregates. On the other hand, the dry method is a method of dry-treating a surface treatment agent after production of magnesium hydroxide, a method of using a surface treatment agent by a method such as using as a dispersant at the time of mixing with a resin, and the dry method is a surface treatment method. preferable.
(D) The amount of the surface treatment agent used is preferably in the range of 0.5 to 10% by mass, preferably 1 to 8% by mass with respect to (B) the metal hydrate.

(C) Functional group containing polyolefin resin In the flame-retardant resin composition of this invention, (C) functional group containing polyolefin resin can be mix | blended as needed. The functional group-containing polyolefin resin has (A) good compatibility with the thermoplastic resin, (B) the coupling effect with magnesium hydroxide is remarkable, the mechanical strength of the flame retardant resin composition, at the time of combustion It is used as a role of promoting the formation of carbonized layer (char) and improving flame retardancy.
Examples of the (C) functional group-containing polyolefin resin include olefins and α, β-unsaturated carboxylic acid random copolymers or metal salts thereof and modified polyolefin resins.
The olefin and α, β-unsaturated carboxylic acid random copolymer is a copolymer of an olefin such as ethylene or propylene and an acid anhydride group-containing monomer such as (meth) acrylic acid or maleic anhydride, Among them, an anhydride group-containing olefin random copolymer is preferable.

An acid anhydride group-containing olefin-based random copolymer or a metal salt thereof is a copolymer of an olefin such as ethylene or propylene and an acid anhydride group-containing monomer such as maleic anhydride, and as described above, Although it can be used as an ethylene / α, β-unsaturated carboxylic acid ester copolymer for flame retardant resin materials, it can be modified to improve flame retardancy and mechanical strength in the same way as modified polyolefin resins. It can be used as a resin.
Examples of the acid anhydride group-containing monomer include the comonomers mentioned above as a copolymer of ethylene and an α, β-unsaturated carboxylic acid or a derivative thereof. Preferred copolymers include ethylene / maleic anhydride copolymers, ethylene / maleic anhydride / vinyl acetate copolymers, ethylene / maleic anhydride / methyl acrylate copolymers, ethylene / maleic anhydride / acrylic acid. Binary or ternary copolymers such as ethyl copolymers can be mentioned. Examples of the metal of the metal salt include K, Na, Li, Ca, Zn, Mg, and Al.
Moreover, the compounding quantity of an acid anhydride group containing olefin type random copolymer or its metal salt is 1-30 mass% in 100 mass% of resin components containing (A) polyolefin resin, Preferably it is 1-20 mass. %, More preferably 1 to 10% by mass (however, the sum of the component (A) and the component (C) is 100% by mass).

    The modified polyolefin resin includes (i) an unsaturated carboxylic acid or derivative thereof, (ii) an epoxy group-containing compound, (iii) a hydroxyl group-containing compound, (iV) an amino group-containing compound, (v) an organosilane compound, ( vi) A polyolefin resin graft-modified with a functional group-containing compound such as an organic titanate compound can be used.

  (I) Unsaturated carboxylic acids or derivatives thereof include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, furan acid, crotonic acid, vinyl acetic acid, pentenoic acid; maleic acid, fumaric acid, citraconic acid, itaconic acid And α, β-unsaturated dicarboxylic acids or anhydrides, or metal salts thereof.

  As the above (ii) epoxy group-containing compound, glycidyl acrylate, glycidyl methacrylate, itaconic acid monoglycidyl ester, butenetricarboxylic acid monoglycidyl ester, butenetricarboxylic acid diglycidyl ester, butenetricarboxylic acid triglycidyl ester and α-chloroallyl, Examples include glycidyl esters such as maleic acid, crotonic acid, and fumaric acid, or glycidyl ethers such as vinyl glycidyl ether, allyl glycidyl ether, glycidyloxyethyl vinyl ether, and styrene-p-glycidyl ether, and p-glycidyl styrene. Preferable examples include glycidyl methacrylate and allyl glycidyl ether.

  Examples of the (iii) hydroxyl group-containing compound include 1-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and hydroxyethyl (meth) acrylate.

  Examples of the (iv) amino group-containing compound include tertiary amino groups such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and dibutylaminoethyl (meth) acrylate.

  Examples of the (v) organosilane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetylsilane, vinyltrichlorosilane, and the like.

  Examples of the (vi) organic and tetrakis titanate compounds include tetraisopropyl titanate, tetra-n-butyl titanate (2-ethylhexoxy) titanate, and titanium lactate ammonium.

  The content of the functional group-containing compound in the modified polyolefin resin is selected in the range of 0.05 to 10% by mass, preferably 0.1 to 8.0% by mass. If the said content is less than 0.05 mass%, the effect of this invention is not enough and the possibility that the coupling effect of resin and a flame retardant may not be exhibited arises. On the other hand, if it exceeds 10% by mass, there is a risk that decomposition and cross-linking reaction may occur at the time of modification.

The modified polyolefin resin is obtained by modifying a functional group-containing compound by heating in the presence of an organic peroxide. Those having a functional group-containing compound content of 0.05 to 10% by mass, or those obtained by mixing the modified product with an unmodified polyolefin resin and adjusting the content to the above range are used.
As the polyolefin resin used for the modification, the polyolefin resin and a mixture thereof can be used. Among these, an ethylene homopolymer or an ethylene / α-olefin copolymer having a density of 0.87 to 0.97 g / cm ³ can be mentioned. Excellent compatibility with magnesium hydroxide, maintaining heat resistance without impairing flexibility of soft resin, promoting formation of carbonized layer during combustion, improving flame retardancy, and improving mechanical strength Most preferred.

(E) Other components In the flame-retardant resin composition of the present invention, in order to further improve performance, combined use of metal hydrates such as magnesium hydroxide and aluminum hydroxide not included in the present invention, flame retardant aid You may mix | blend additives, such as an agent.
Red flame retardant, antimony trioxide, antimony pentoxide, calcium phosphate, zircon oxide, titanium oxide, zinc oxide, magnesium oxide, calcium carbonate, magnesium carbonate, barium sulfate, barium borate, barium metaborate, boron Zinc acid, zinc metaborate, molybdenum disulfide, clay, diatomaceous earth, kaolinite, montmorillonite, hydrotalcite, talc, silica, white carbon, zeolite, hydromagnesite, organic bentonite, and the like may be used in combination. These flame retardant aids are desirably blended up to 50% by mass with respect to the (B) metal hydrate.

  Furthermore, the flame retardant resin composition of the present invention can be blended with various additives and auxiliary materials in accordance with the intended use within a range that does not impair the characteristics of the present invention. These additives and auxiliary materials include stabilizers, antioxidants, UV absorbers, light stabilizers, antistatic agents, processability improvers, fillers, copper damage inhibitors, neutralizers, foaming agents, and bubbles. Examples thereof include an inhibitor, a colorant, process oil, and carbon black. Further, it can be crosslinked by adding a crosslinking agent such as an organic peroxide, sulfur or a silane-based crosslinking agent or a crosslinking aid, or can be crosslinked by irradiating with ionizing radiation.

2. Composition ratio of component When the composition ratio of each component in the flame retardant resin composition of the present invention is composed of component (A) and component (B), (A) with respect to 100 parts by mass of thermoplastic resin, (B) 30-250 mass parts of metal hydrates, Preferably it is 50-200 mass parts, More preferably, it is 80-150 mass parts. When the blending amount of the metal hydrate is less than 30 parts by mass, the flame retardancy is insufficient, and when it exceeds 250 parts by mass, the mechanical strength is lowered.

Moreover, when it is comprised with (A) component, (B) component, and (C) component, with respect to 100 mass parts of resin components which consist of (A) thermoplastic resin and (C) functional group containing polyolefin polymer, (B) It is comprised with the composition of 30-250 mass parts of metal hydrates. When the component (B) is less than 30 parts by mass, the flame retardancy is not sufficient, and when it exceeds 250 parts by mass, the material becomes hard and the flexibility and mechanical strength of the product may be lost. There is a risk of harm such as scratching and whitening.
The component (C) is not necessarily required when the resin component is sufficiently soft, but is generally 1 to 30% by mass, preferably 1 to 20% by mass with respect to the (A) thermoplastic resin. %, More preferably 1 to 15% by mass. Due to the presence of this component (C), a coupling effect between (A) the thermoplastic resin and (B) magnesium hydroxide is produced, and a carbonized layer is formed at the time of combustion, thereby improving the flame retardancy. . Moreover, even if it mix | blends the quantity exceeding 30 mass%, not only the improvement of the mechanical strength beyond it can be expected, but there exists a possibility that material may become hard on the contrary.

3. Production of Flame Retardant Resin Composition The flame retardant resin composition of the present invention comprises the component (A), the component (B) and, if necessary, the component (C) in any order in the following proportions. It is obtained by blending, kneading and granulating using a normal kneader such as a single screw extruder, twin screw extruder, super mixer, Henschel mixer, Banbury mixer, roll mixer, Brabender plastograph, kneader. In this case, it is preferable to select a kneading and granulating method capable of improving the dispersion of each component, and it is preferable to knead and granulate using a twin screw extruder.

4). Use of flame retardant resin composition The flame retardant resin composition of the present invention is a resin composition excellent in various properties such as high flame retardancy, easy cutability and mechanical strength. It can be used for an insulating layer and / or a sheath layer, a semiconductive layer, a flame retardant sheet, etc., such as an optical fiber cable. Electric wires, cords, cables, and optical fiber cables using the flame-retardant resin composition of the present invention for the insulating layer and / or sheath layer have good product appearance, terminal cutting efficiency, excellent workability, workability, etc. It has the following characteristics.

5. Electric wire / cable The electric wire or cable of the present invention is an electric wire / cable using the above composition, and is an insulating layer, a sheath layer, an internal semiconductive layer and / or an external semiconductive layer, or optionally copper, aluminum, You may provide the coating layer normally provided in an electric wire, a cable, etc., such as an external metal shielding layer, such as lead, and a water shielding layer wound with aluminum tape or the like. Moreover, the manufacturing method of this electric wire and cable may be a general method, and may be used in a crosslinked or non-crosslinked manner, and is not particularly limited.
Further, it may be used by foaming, such as a communication cable, or may be used by being laminated with another base material such as a thermoplastic resin or a metal foil.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded. The measurement / test methods used in Examples and Comparative Examples and the materials used are as follows.

1. Measurement / Test Method (1) Density The density was measured based on the test method of JIS K6922-1 (1997).
(2) Melt mass flow rate (MFR)
Based on the test method of JIS K6922-1 (1997), measurement was performed under condition D (temperature 190 ° C., load 21.18 N).
(3) Measurement of average particle diameter The average particle diameter of the metal hydrate (magnesium hydroxide) was measured using a laser diffraction / scattering particle size distribution measuring apparatus LA-920 manufactured by Horiba, Ltd. The product was adjusted to the following transmittance and added, and after ultrasonic treatment for 1 minute, it was calculated based on the volume reference distribution measured under the following conditions, and the average particle diameter (arithmetic average diameter) was obtained. .
Transmittance (L): 80-90%
Transmittance (H): 70-80%
Relative refractive index: 1.14
Shape factor: 1.0
Number of data acquisition: 10 times Number of repetitions: 15 (4) Measurement of average particle size of primary particles and confirmation of aggregation structure Using palladium field emission scanning electron microscope S-800 manufactured by Hitachi, Ltd., platinum palladium was added to a magnesium hydroxide sample. After vapor deposition, the morphology was observed under the following conditions to confirm the presence or absence of an agglomerated structure.
Acceleration voltage: 15 kV
Working distance: 15mm
Observation magnification: Photographing at 2000 to 30000 times Subsequently, from the obtained photograph, each major axis was measured with respect to appropriate magnesium hydroxide under the following conditions, and the length average particle diameter and logarithmic particles of 0.01 to 10 μm were measured. A number-based distribution consisting of diameter categories was determined.
Number of particles to be measured: 200 to 300 in a uniform crystal structure having flat crystals and flat hexagonal crystals
About 1300 in non-uniform crushing structure Observation magnification: 5000 to 30000 times (5) Measurement of specific surface area of BET method About 0.3 g of magnesium hydroxide using a fully automated powder specific surface area measuring device AMS-8000 manufactured by Okura Riken Was pretreated by nitrogen flow at 250 ° C. for 15 minutes, and then the specific surface area was measured with the following adsorption gas under liquid nitrogen.
Adsorption gas amount: 30% nitrogen / 70% helium
(6) Oxygen index Based on the test method of JIS K7201-1 (1999), it was measured using an IV type test piece punched from a press sheet having a thickness of 3 mm. Large numbers indicate excellent flame retardancy.
(7) Easy cutability Based on a test method for tensile impact strength (JIS K7160 (1996)), measurement was performed using a 4-type test piece punched from a 1 mm thick press sheet. It was used as an index (the lower the value, the better the cutting performance and the better the cutting ability).
[Easy cutting property]
A: Tensile impact strength is 400 KJ / m ² or less, and it is easy to cut low. Δ: Tensile impact strength is 450 KJ / m ² or less, and it is easy to cut.
X: The tensile impact strength hardly exceeds 450 KJ / m ² and ductile fracture is observed.
(8) Tensile strength and elongation Based on the JIS C3005 (2000) 4.16 insulator and sheath tensile test method, a tensile speed of 200 mm was obtained using a dumbbell-shaped No. 3 test piece punched from a 1 mm thick press sheet. / Min. The test results are shown in Table 2.

2. Materials used (A1) Polyolefin resin (a11) Ethylene / ethyl acrylate copolymer MFR: 0.8 g / 10 min Ethyl acrylate content: 15% by mass
Brand name: Lexpearl EEA, A1150 Nippon Polyethylene Co., Ltd. (a12) Ethylene / ethyl acrylate copolymer MFR: 5 g / 10 min Ethyl acrylate content: 20% by mass
Brand Name: Lexpearl EEA, A4200 Nippon Polyethylene Co., Ltd. (a2) ethylene / vinyl acetate copolymer MFR: 1 g / 10 min Vinyl acetate content: 15% by mass
Brand name: Novatec EVA, LV430 Nippon Polyethylene Co., Ltd. (a3) linear low density polyethylene MFR: 0.6 g / 10 min Density: 0.922 g / cm ³
Brand Name: Novatec LL, UE320 (A2) Olefin Elastomer / Ethylene 1-Octene Copolymer MFR: 0.5 g / 10 min Density: 0.863 g / cm ³
Brand Name: Engagement 8180 Dow Chemical Japan Co., Ltd.

(B) Metal hydrate (b1) Magnesite ore (magnesium carbonate) is fired at about 850 ° C. and then pulverized, and lightly pulverized with a fine powder having an average particle size of 3 μm using a laser light diffraction / scattering particle size distribution analyzer I got magnesia. The obtained light-burned magnesia was stirred in water at a concentration of 30% by weight and a temperature of about 50 ° C., and hydrated in an alkaline solution to which 0.2% by weight of sodium hydroxide was added to the light-burned magnesia for about 2 hours. After the reaction, filtration under reduced pressure, washing with water, and drying at 120 ° C. for about 2 hours. In the obtained magnesium hydroxide, it was confirmed by a scanning electron microscope that uniform primary hexagonal primary particles formed an aggregated structure (see FIGS. 1A and 1B). The average particle diameter is 2.7 μm (see FIG. 6) measured by a laser diffraction / scattering particle size distribution measuring device, and the length is based on the number-based particle size distribution in the major axis direction of primary particles measured from a morphological photograph using a scanning electron microscope. This was magnesium hydroxide having a mean particle size of 0.11 μm, primary particles of 0% (see FIG. 11) of 5 μm or more, and a BET specific surface area of 16 m ² / g. The physical properties are shown in Table 1.

(B2) To an aqueous 15 mol / l magnesium chloride solution obtained from bitter broth, an equivalent aqueous calcium hydroxide solution was added at 40 ° C. with stirring at a rate of about 2 l / h and reacted. The obtained magnesium hydroxide was filtered under reduced pressure and washed with water. Thereafter, 6 l of water per 15 mol of magnesium hydroxide was added and subjected to hot water treatment at 250 ° C. for about 8 hours in an autoclave, followed by filtration under reduced pressure, washing with water, and drying at 120 ° C. for about 2 hours. In the obtained magnesium hydroxide, it was confirmed by a scanning electron microscope that the primary particles of flat crystals had an aggregated structure (see FIGS. 2-a and 2-b), and the average particle size was 4.2 μm. (See FIG. 7) The primary particles had a length average particle size of 0.12 μm, primary particles of 5 μm or more were 0% (see FIG. 12), and the BET method specific surface area was 23 m ² / g of magnesium hydroxide. . The physical properties are shown in Table 1.

(B3) To an aqueous 15 mol / l magnesium chloride solution obtained from bitter juice, an equivalent aqueous calcium hydroxide solution was added at 40 ° C. with stirring at a rate of about 2 l / h and reacted. The obtained magnesium hydroxide was filtered under reduced pressure, washed with water, and dried at 120 ° C. for about 2 hours. In the obtained magnesium hydroxide, it was confirmed by a scanning electron microscope that the primary particles of flat crystals had an aggregated structure (see FIGS. 3-a and 3-b), and the average particle size was 6.2 μm. (See FIG. 8). The primary particles had a length average particle size of 0.14 μm, primary particles of 5 μm or more were 0% (see FIG. 13), and BET method specific surface area was 38 m ² / g of magnesium hydroxide. . The physical properties are shown in Table 1.

(B4) Magnesium hydroxide produced by pulverizing brucite ore (natural magnesium as a main component) and mixing a surface treatment agent by a dry method (brand name: Magsees W-R4, manufactured by Kamishima Chemical Co., Ltd.) Was measured in the same manner as above, and was confirmed to be a mixture of primary particles from fine particles to coarse particles and aggregates thereof by a scanning electron microscope (see FIG. 4), and the average particle size was 3.8 μm. (See FIG. 9) Magnesium hydroxide having a primary particle length average particle diameter of 0.40 μm, primary particles of 5 μm or more being 0.4% (see FIG. 14), and a specific surface area of 6.5 m ² / g. there were. The physical properties are shown in Table 1.

(B5) Magnesium hydroxide (brand name: Kisuma 5A, manufactured by Kyowa Chemical Industry Co., Ltd.) synthesized from magnesium chloride obtained from seawater and mixed with a surface treatment agent by a wet method is the same as above. Measured and composed of relatively uniform primary particles by a scanning electron microscope, almost no aggregation structure was confirmed (see FIG. 5). Further, the average particle size is 2.2 μm (see FIG. 10), the primary particle length average particle size is 0.68 μm, the primary particles of 5 μm or more are 0% (see FIG. 15), and the specific surface area is 4.9 m ^2. / G magnesium hydroxide. The physical properties are shown in Table 1.

(C) Functional group-containing polyolefin resin (c1) Maleic anhydride-modified linear low-density polyethylene: MFR 2 g / 10 min, density 0.923 g / cm ³ linear low-density polyethylene 100 parts by mass, maleic anhydride 0. 25 parts by mass, maleic anhydride-modified linear low density polyethylene (maleic anhydride content 0.2) obtained by blending 0.02 part by mass of perhexine 25B as an organic peroxide and melt kneading with an extruder mass%).
(C2) Ethylene / maleic anhydride / methyl acrylate copolymer MFR: 7 g / 10 min Density: 0.93 g / cm ³
Brand name: Lexpearl ET, ET230X Made by Nippon Polyethylene

(D) Surface treatment agent (d1) Stearic acid (d2) Lithium stearate (d3) Sorbitan monostearate (d4) Castor oil (E) Carbon black (VULKAN 9A32 manufactured by CABOT CORPORATION)

Example 1
(I) Preparation of flame retardant resin composition (a11) 85 mass% of ethylene / ethyl acrylate copolymer, (a3) 100 mass parts of polyethylene resin (A) composed of 15 mass% of linear low density polyethylene, (B) Using 70 parts by mass of magnesium hydroxide of (b1) as a metal hydrate and (E) a composition obtained by blending 1.5 parts by mass of carbon black, using a 100 L tumbler mixer, about 50 rpm, Rotating mixing was performed for minutes. The obtained mixture was kneaded, extruded and pelletized under the following conditions to obtain a flame retardant resin composition.
(Ii) Kneading conditions Extruder: Twin screw extruder NCM50 manufactured by Nakatani Manufacturing Co., Ltd.
Kneader temperature / number of revolutions: 180 ° C./500 rpm
Screw part temperature / rotation speed: 170 ° C./65 rpm
(Iii) Preparation of test piece The obtained flame-retardant resin composition was roll-kneaded at 140 ° C for 5 minutes and then press-molded to obtain press sheets having a thickness of 1 mm and a thickness of 3 mm.
Test pieces were prepared from the press sheet, each test was performed, and the test results are shown in Table 2.

(Example 2)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene (D1) 0.7 part by mass of stearic acid (D1) as a surface treating agent is mixed with 70 parts by mass of magnesium hydroxide of (b1), and a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes with a 20 L super mixer, A composition obtained by mixing 70.7 parts by mass of the obtained magnesium hydroxide / surface treating agent mixture and 1.5 parts by mass of (E) carbon black was mixed in a dry manner, and the same composition as in Example 1 was used. Mixing, kneading, and extrusion were carried out by the method to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

(Example 3)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene 70 parts by weight of magnesium hydroxide of (b1), (D) 2.1 parts by weight of stearic acid as a surface treating agent are mixed, and a 20 L supermixer is used at a temperature of about 80 ° C., a rotational speed of about 600 rpm, and a dry process. In the same manner as in Example 1, a composition comprising 72.1 parts of the magnesium hydroxide / surface treating agent mixture obtained and 1.5 parts by weight of (E) carbon black was mixed. Mixing, kneading, and extrusion were performed to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

Example 4
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene (D1) 3.5 parts by mass of stearic acid (D1) as a surface treatment agent is mixed with 70 parts by mass of magnesium hydroxide of (b1), and a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes with a 20 L supermixer, A composition obtained by mixing 73.5 parts by mass of the obtained magnesium hydroxide / surface treatment agent mixture and 1.5 parts by mass of (E) carbon black was mixed in the dry method, and the same composition as in Example 1 was used. Mixing, kneading, and extrusion were carried out by the method to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

(Example 5)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene (D1) 2.1 parts by mass of lithium stearate as (D) surface treatment agent is mixed with 70 parts by mass of magnesium hydroxide of (b1), and a temperature of about 80 ° C. and a rotation speed of about 600 rpm for 10 minutes with a 20 L super mixer. The composition obtained by mixing 72.1 parts by mass of the obtained magnesium hydroxide / surface treatment agent and 1.5 parts by mass of (E) carbon black was mixed in the dry method, and the same as in Example 1. The flame retardant resin composition was obtained by mixing, kneading and extruding by the above method. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

(Example 6)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene (D1) 2.1 parts by mass of sorbitan monostearate as a surface treating agent is mixed with 70 parts by mass of magnesium hydroxide of (b1), and a temperature of about 80 ° C. and a rotation speed of about 600 rpm are obtained with a 20 L super mixer. Example 1 was prepared by mixing 72.1 parts by mass of the obtained magnesium hydroxide / surface treatment agent mixture and 1.5 parts by mass of (E) carbon black. Mixing, kneading, and extrusion were performed in the same manner to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

(Example 7)
(B) Metal hydrate (b1) with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass and (a3) 15% by mass of linear low density polyethylene (D) As a surface treatment agent, (d4) 2.1 parts by weight of castor oil is mixed with 70 parts by mass of magnesium hydroxide, and mixed by a dry method with a 20 L super mixer at a temperature of about 80 ° C. and a rotation speed of about 600 rpm for 10 minutes. Then, 72.1 parts by mass of the obtained magnesium hydroxide / surface treatment mixture and (E) 1.5 parts by mass of carbon black were mixed in the same manner as in Example 1, Kneading and extrusion were performed to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

(Example 8)
(A11) 85 parts by mass of ethylene / ethyl acrylate copolymer, (a3) 100 parts by mass of polyethylene resin consisting of 15% by mass of linear low density polyethylene, (D) 2.1 parts by mass of stearic acid as a surface treating agent is mixed with 70 parts by mass of magnesium hydroxide, and mixed by a dry method at room temperature with a rotation speed of about 600 rpm for 1 minute using a 20 L super mixer. The composition obtained by blending 72.1 parts by mass of the obtained magnesium hydroxide / surface treating agent mixture and 1.5 parts by mass of (E) carbon black was mixed, kneaded and extruded in the same manner as in Example 1. A flame retardant resin composition was obtained. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 2.

Example 9
(A11) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low-density polyethylene, and (C) a functional group-containing polyolefin (c1) maleic anhydride With respect to 100 parts by mass of a resin component composed of 5% by mass of a modified linear low density polyethylene, (B) 70 parts by mass of magnesium hydroxide (b1) as a metal hydrate, (D) (d1 as a surface treatment agent) ) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the resulting magnesium hydroxide / surface treatment agent mixture 72.1 A flame retardant resin composition is obtained by mixing, kneading, and extruding a composition obtained by blending part by mass and 1.5 parts by mass of (E) carbon black in the same manner as in Example 1. .
Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 3.

(Example 10)
(A11) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low-density polyethylene, and (C) a functional group-containing polyolefin (c1) maleic anhydride With respect to 100 parts by mass of a resin component comprising 5% by mass of a modified linear low density polyethylene, (B) 150 parts by mass of magnesium hydroxide (b1) as a metal hydrate, (D) (d1 as a surface treatment agent) ) Mix 4.5 parts by weight of stearic acid, mix with a 20 L super mixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and obtain a magnesium hydroxide / surface treatment agent mixture 154.5 A flame retardant resin composition obtained by mixing, kneading, and extruding a composition obtained by blending part by mass and 1.5 parts by mass of (E) carbon black in the same manner as in Example 1. Obtained. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 3.

(Example 11)
(A11) Ethylene / ethyl acrylate copolymer 80% by mass, (a3) linear low-density polyethylene 15% by mass polyethylene resin (A), and (C) functional group-containing polyolefin (c2) ethylene / anhydrous For 100 parts by mass of the resin component consisting of 5% by mass of maleic acid / methyl acrylate copolymer, (B) 70 parts by mass of magnesium hydroxide (b1) as a metal hydrate, (D) as a surface treatment agent (D1) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the resulting magnesium hydroxide / surface treatment agent mixture 72 A composition comprising 1 part by mass and (E) 1.5 parts by mass of carbon black was mixed, kneaded and extruded in the same manner as in Example 1 to produce a flame retardant resin group. To obtain things. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 3.

(Example 12)
(B) Metal hydrate (B) with respect to 100 parts by mass of polyethylene resin (A) consisting of 85% by mass of ethylene / vinyl acetate copolymer (a3) 15% by mass of linear low density polyethylene (A) (D) Surface treatment agent (d1) 2.1 parts by mass of stearic acid is mixed with 70 parts by mass of magnesium hydroxide of b1), and a dry method using a 20 L super mixer at a temperature of about 80 ° C. and a rotation speed of about 600 rpm for 10 minutes. In the same manner as in Example 1, a composition comprising 72.1 parts by mass of the obtained magnesium hydroxide / surface treatment agent mixture and 1.5 parts by mass of (E) carbon black was mixed. Mixing, kneading, and extrusion were performed to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 3.

(Example 13)
(A11) 90% by mass of ethylene / ethyl acrylate copolymer, (A2) 100 parts by mass of polyethylene resin (A) composed of 10% by mass of ethylene / 1-octene copolymer as olefin elastomer (B ) 70 parts by weight of magnesium hydroxide of (b1) as a metal hydrate, (D) 2.1 parts by weight of stearic acid as a surface treating agent are mixed, and a temperature of about 80 ° C. and rotation speed with a 20 L super mixer. A composition obtained by mixing 72.1 parts by mass of the obtained magnesium hydroxide / surface treatment agent mixture at about 600 rpm for 10 minutes and 1.5 parts by mass of (E) carbon black, Mixing, kneading, and extrusion were performed in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 3.

(Example 14)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene A composition obtained by blending 1.5 parts by mass of (E) carbon black with 70 parts by mass of magnesium hydroxide of (b2) is mixed, kneaded and extruded in the same manner as in Example 1, and is a flame retardant resin. A composition was obtained. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Example 15)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene (D2) 2.1 parts by mass of stearic acid (D1) as a surface treating agent is mixed with 70 parts by mass of magnesium hydroxide of (b2), and a temperature of about 80 ° C., a rotation speed of about 600 rpm, 10 minutes with a 20 L super mixer, A composition obtained by mixing 72.1 parts by mass of the obtained magnesium hydroxide / surface treating agent mixture and 1.5 parts by mass of (E) carbon black was mixed in the dry method, and the same composition as in Example 1 was used. Mixing, kneading, and extrusion were carried out by the method to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Example 16)
(A11) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low-density polyethylene, and (C) a functional group-containing polyolefin (c1) maleic anhydride With respect to 100 parts by mass of a resin component consisting of 5% by mass of a modified linear low-density polyethylene, (B) 70 parts by mass of magnesium hydroxide (b2) as a metal hydrate, (D) surface treatment agent (d1) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L super mixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the obtained magnesium hydroxide / surface treatment agent mixture 72.1 parts by mass Part and (E) a composition comprising 1.5 parts by mass of carbon black were mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Example 17)
(A12) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low density polyethylene, and (C) (c1) maleic anhydride as a functional group-containing polyolefin With respect to 100 parts by mass of a resin component composed of 5% by mass of a modified linear low density polyethylene, (B) 70 parts by mass of magnesium hydroxide (b2) as a metal hydrate, (D) as a surface treatment agent (d1 ) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the resulting magnesium hydroxide / surface treatment agent mixture 72.1 A flame retardant resin composition is obtained by mixing, kneading, and extruding a composition obtained by blending part by mass and 1.5 parts by mass of (E) carbon black in the same manner as in Example 1. . Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Example 18)
(A11) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low-density polyethylene, and (C) a functional group-containing polyolefin (c1) maleic anhydride With respect to 100 parts by mass of a resin component consisting of 5% by mass of a modified linear low density polyethylene, (B) 70 parts by mass of magnesium hydroxide (b3) as a metal hydrate, (D) as a surface treatment agent (d1 ) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the resulting magnesium hydroxide / surface treatment agent mixture 72.1 A flame retardant resin composition is obtained by mixing, kneading, and extruding a composition obtained by blending part by mass and 1.5 parts by mass of (E) carbon black in the same manner as in Example 1. . Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Example 19)
(A12) 80% by mass of ethylene / ethyl acrylate copolymer, (a3) polyethylene resin (A) of 15% by mass of linear low density polyethylene, and (C) (c1) maleic anhydride as a functional group-containing polyolefin With respect to 100 parts by mass of a resin component consisting of 5% by mass of a modified linear low density polyethylene, (B) 70 parts by mass of magnesium hydroxide (b3) as a metal hydrate, (D) (d4 as a surface treatment agent) ) 7 parts by weight of castor oil were mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotational speed of about 600 rpm for 10 minutes by a dry method, and 77 parts by weight of the resulting magnesium hydroxide / surface treatment agent mixture, E) A composition obtained by blending 1.5 parts by mass of carbon black was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 4.

(Comparative Example 1)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene A composition obtained by blending 70 parts by mass of magnesium hydroxide (b4) and 1.5 parts by mass of (E) carbon black was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame-retardant resin. A composition was obtained. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

(Comparative Example 2)
(A11) ethylene / ethyl acrylate copolymer 80% by mass, (a3) 15% by mass of linear low-density polyethylene (A), and (C) functional group-containing polyolefin (c1) anhydrous maleic (B) 70 parts by mass of magnesium hydroxide (b4) as a metal hydrate and (E) carbon black 1.5 to 100 parts by mass of a resin component comprising 5% by mass of acid-modified linear low density polyethylene A composition obtained by blending parts by mass was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

(Comparative Example 3)
(A11) ethylene / ethyl acrylate copolymer 80% by mass, (a3) 15% by mass of linear low-density polyethylene (A), and (C) functional group-containing polyolefin (c1) anhydrous maleic (B) 70 parts by mass of magnesium hydroxide (b4) as a metal hydrate, (D) (d1) as a surface treatment agent with respect to 100 parts by mass of a resin component comprising 5% by mass of acid-modified linear low density polyethylene ) 2.1 parts by mass of stearic acid was mixed and mixed with a 20 L supermixer at a temperature of about 80 ° C., a rotation speed of about 600 rpm for 10 minutes by a dry method, and the resulting magnesium hydroxide / surface treatment agent mixture 72.1 A flame retardant resin composition is obtained by mixing, kneading, and extruding a composition obtained by blending part by mass and 1.5 parts by mass of (E) carbon black in the same manner as in Example 1. . Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

(Comparative Example 4)
(A11) ethylene / ethyl acrylate copolymer 80% by mass, (a3) 15% by mass of linear low-density polyethylene (A), and (C) functional group-containing polyolefin (c1) anhydrous maleic (B) 150 parts by mass of magnesium hydroxide (b4) as a metal hydrate and (E) carbon black 1.5 to 100 parts by mass of a resin component comprising 5% by mass of acid-modified linear low density polyethylene A composition obtained by blending parts by mass was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

(Comparative Example 5)
(B) as a metal hydrate with respect to 100 parts by mass of (a11) ethylene / ethyl acrylate copolymer 85% by mass, (a3) polyethylene resin (A) consisting of 15% by mass of linear low density polyethylene A composition obtained by blending 70 parts by mass of magnesium hydroxide (b5) and 1.5 parts by mass of (E) carbon black was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin. A composition was obtained. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

(Comparative Example 6)
(A11) ethylene / ethyl acrylate copolymer 80% by mass, (a3) 15% by mass of linear low-density polyethylene (A), and (C) functional group-containing polyolefin (c1) anhydrous maleic (B) 70 parts by mass of magnesium hydroxide (b5) as a metal hydrate and (E) carbon black 1.5 to 100 parts by mass of a resin component consisting of 5% by mass of acid-modified linear low density polyethylene A composition obtained by blending parts by mass was mixed, kneaded and extruded in the same manner as in Example 1 to obtain a flame retardant resin composition. Using the obtained flame-retardant resin composition, a press sheet was prepared and tested in the same manner as in Example 1. The test results are shown in Table 5.

[Evaluation of Examples]
In Example 1, 100 parts by mass of a predetermined polyethylene resin (A), (B) as a metal hydrate, (A) secondary particles having an aggregated structure have an average particle size of 2.7 μm and a length average particle size of 0 .11 μm and 5 μm or more is a flame retardant resin composition containing 0% primary particles and 70 parts by mass of (b1) magnesium hydroxide having a specific surface area of 16 m ² / g and has an agglomerated structure. The cut property was good (low tensile impact strength), and the BET method specific surface area was large, so that the flame retardancy was high.
In Examples 2 to 4, 100 parts by mass of a predetermined polyethylene resin (A), magnesium hydroxide (b1), and surface treatment agent by dry method at 80 ° C. (D) Influence of addition amount of surface treatment agent (D) When the addition amount of the surface treatment agent increases, the tendency to easily cut and flame retardancy decreases, but the mechanical strength (tensile strength, elongation) is improved, and the balance is improved. The composition was good.
Examples 5 to 7 look at the evaluation of the type of surface treatment agent, and Example 8 looks at the evaluation of the treatment temperature of the surface treatment agent. Magnesium hydroxide is sufficiently dispersed and the particle size is fine, so that mechanical It was a composition with good strength and easy cutability and excellent balance.
In Example 9, maleic anhydride-modified linear low-density polyethylene (C) was further blended with the formulation of Example 3, and easy cutting properties and flame retardancy tend to decrease. The mechanical strength was improved and the composition was well balanced.
Example 10 is a composition obtained by increasing the blending amount of (b1) magnesium hydroxide (150 parts by mass) and the surface treatment agent (4.5 parts by mass) of the metal hydrate of component (B) in Example 9. However, although (b1) a large amount of magnesium hydroxide is used, the mechanical strength is slightly reduced by using a maleic anhydride-modified linear low-density polyethylene and a surface treatment agent in combination, It was a well-balanced composition with improved flame retardancy and easy cutability.

Example 11 is a blend of (C) the functional group-containing polyolefin resin of Example 9 instead of the ethylene / maleic anhydride / methyl acrylate copolymer, and has the same performance as in Example 9. Magnesium hydroxide was sufficiently dispersed and easy-cutability was good.
In Example 12, (a11) the ethylene / ethyl acrylate copolymer was changed to (a2) the ethylene / vinyl acetate copolymer, and it was excellent in the balance between easy cutting properties and mechanical strength.
In Example 13, 90% by mass of (a11) ethylene / ethyl acrylate copolymer was mixed with 10% by mass of ethylene / 1-octene copolymer as (A2) olefin elastomer, and the ease of cutting was reduced. However, the mechanical strength was high and the balance was excellent.
In Example 14, 100 parts by mass of a predetermined polyethylene resin (A), (B) as a metal hydrate, (a) an average particle size of secondary particles having an aggregated structure of 4.2 μm, and an average particle size of length A flame retardant resin composition in which particles of 0.12 μm and 5 μm or more are blended with 0% primary particles and 70 parts by mass of (b2) magnesium hydroxide having a specific surface area of 23 m ² / g. Aggregation as in Example 1 Since it has a structure, it was easy to cut, and because of its large specific surface area, it had high flame retardancy.
Example 15 is obtained by adding (D) a surface treatment agent to magnesium hydroxide of (b2) as a predetermined polyethylene-based resin (A) and (B) metal hydrate. And although easy-cut property and a flame retardance show the tendency to fall, mechanical strength (tensile strength and elongation improved and it was excellent in balance.

In Example 16, the composition of Example 15 was further blended with (c1) maleic anhydride-modified linear low-density polyethylene as the functional group-containing polyolefin resin of component (C). However, the easy-cutting property tends to decrease, but the mechanical strength is improved and the balance is excellent.
In Example 17, the MFR of the (a11) ethylene / ethyl acrylate copolymer used in Example 16 was increased, and the mechanical strength tends to decrease, but the easy-cutting property is improved. In addition, as the MFR was increased, the fluidity of the molten resin composition was improved and the balance was excellent.
In Example 18, 100 parts by mass of a predetermined polyethylene resin (A), (B) a metal hydrate, (a) an average particle size of secondary particles having an aggregated structure of 6.2 μm, and an average particle size of length It is a flame retardant resin composition in which particles of 0.14 μm and 5 μm or more are added with 0% primary particles, (b3) 70 parts by mass of magnesium hydroxide having a specific surface area of 38 m ² / g, and (D) a surface treatment agent. As in Example 1, since it has an agglomerated structure, it was easy to cut, and because of its large specific surface area, the flame retardancy was high.
In Example 19, instead of the ethylene / ethyl acrylate copolymer (a11) used in Example 18, the MFR was increased (a12) using an ethylene / ethyl acrylate copolymer, Although the strength tends to decrease, the easy-cut property is improved and the fluidity of the molten resin composition is also improved.

[Evaluation of Comparative Example]
In Comparative Examples 1 to 3, 100 parts by mass of a predetermined polyethylene resin (A) is blended with magnesium hydroxide (b4) obtained by pulverizing brucite ore as (B) metal hydrate. Although the primary particles are confirmed to form an agglomerated structure, the particle size is a non-uniform structure including fine particles to coarse particles, and the specific surface area is also small. It was inferior in flame retardancy.
In Comparative Example 4, 100 parts by mass of a predetermined polyethylene-based resin (A) is obtained by increasing the blending amount of magnesium hydroxide (b4) as (B) metal hydrate. However, since many primary particles of 5 μm or more are contained as magnesium hydroxide, the number of coarse particles is large and the amount of the compound is large, so that the mechanical strength is poor.
Comparative Examples 5 and 6 are compositions in which 100 parts by mass of a predetermined polyethylene resin (A) is blended with magnesium hydroxide (b5) synthesized from magnesium chloride in seawater as (B) metal hydrate. The magnesium hydroxide of (b5) had a small average particle size and did not form an agglomerated structure, and was excellent in mechanical strength but high in tensile impact strength and inferior in easy cutability.

  The flame retardant resin composition of the present invention is a resin composition that retains the performance of the conventional non-halogen flame retardant resin composition and is excellent in various performances such as flame retardancy, easy cut property, and mechanical strength. It can be used for insulation layers and / or sheath layers of electric wires, cables, optical fiber cables and the like. In addition, electric wires, cables, optical fiber cables, etc., using the flame-retardant resin composition of the present invention have good easy-cutting properties, so they have excellent terminal cutting processability, good workability and workability, and are industrial. Can be suitably used.

It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 20,000 times) of magnesium hydroxide b1. Uniform primary particles are observed. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 5,000 times) of magnesium hydroxide b1. It is observed that the primary particles form an aggregate structure. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 30,000 times) of magnesium hydroxide b2. Uniform primary particles are observed. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 5000 times) of magnesium hydroxide b2. It is observed that the primary particles form an aggregate structure. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 30,000 times) of magnesium hydroxide b3. Uniform primary particles are observed. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 5,000 times) of magnesium hydroxide b3. It is observed that the primary particles form an aggregate structure. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 5,000 times) of magnesium hydroxide b4. It is observed that non-uniform particles can be observed and that minute particles are aggregated. It is a form photograph (Hitachi, Ltd. field emission type scanning electron microscope S-800, 5,000 times) of magnesium hydroxide b5. Uniform primary particles that do not form an aggregated structure are observed. It is a volume-based particle size distribution of magnesium hydroxide b1 (Laser diffraction / scattering particle size distribution measuring apparatus LA-920 manufactured by Horiba, Ltd.). It is a volume-based particle size distribution of magnesium hydroxide b2 (Horiba Seisakusho Laser Light Diffraction / Scattering Particle Size Distribution Measuring Device LA-920). It is a volume-based particle size distribution of magnesium hydroxide b3 (Horiba Seisakusho Laser Light Diffraction / Scattering Particle Size Distribution Measuring Device LA-920). It is a volume-based particle size distribution of magnesium hydroxide b4 (Horiba Seisakusho Laser Light Diffraction / Scattering Particle Size Distribution Measuring Device LA-920). It is a volume-based particle size distribution of magnesium hydroxide b5 (Horiba Seisakusho Laser Light Diffraction / Scattering Particle Size Distribution Measuring Device LA-920). It is the number standard particle size distribution (measured from Hitachi, Ltd. field emission scanning electron microscope S-800, 20,000 times) in the major axis direction of magnesium hydroxide b1. It is a number standard particle size distribution (measured from Hitachi, Ltd. field emission scanning electron microscope S-800, 30,000 times) in the major axis direction of magnesium hydroxide b2. It is a number standard particle size distribution (measured from Hitachi, Ltd. field emission scanning electron microscope S-800, 30,000 times) in the major axis direction of magnesium hydroxide b3. It is a number standard particle size distribution (measured from Hitachi, Ltd. field emission scanning electron microscope S-800, 10,000 times) in the major axis direction of magnesium hydroxide b4. It is the number standard particle size distribution (measured from Hitachi, Ltd. field emission scanning electron microscope S-800, 5,000 times) in the major axis direction of magnesium hydroxide b5.

Claims (8)

(A) 100 parts by mass of a thermoplastic resin and (B) (B1) 30 to 250 parts by mass of magnesium hydroxide which is a metal hydrate that satisfies the following conditions (a) to (c) A flame retardant resin composition.
(B) The average particle diameter (arithmetic average diameter) calculated based on the volume-based particle size distribution measured by a laser light diffraction / scattering particle size distribution measuring device is in the range of 1 to 10 μm. From a morphological photograph taken with a scanning electron microscope, it was observed that secondary particles composed of aggregates formed of primary particles were included, and the length was based on the number-based particle size distribution in the major axis direction of the primary particles measured from the morphological photograph. The average particle size is in the range of 0.01 to 0.5 μm, and the particle size of 5 μm or more is 0.1% or less. (C) The specific surface area by the BET method is 8.0 m ² / g or more. (B) The flame retardant resin composition according to claim 1, wherein the metal hydrate further satisfies the following condition (d):
(D) The ratio of the average particle diameter measured by a laser light diffraction / scattering particle size distribution measuring instrument to the average particle diameter of primary particles measured from a morphological photograph by a scanning electron microscope is 5 or more. The flame retardant resin composition according to claim 1 , wherein (B1) magnesium hydroxide is produced by a synthesis method. (B1) magnesium hydroxide by synthesis method, those obtained by adding an alkali substance in an aqueous solution containing magnesium salt, or a magnesium oxide is obtained by hydration in claim 3, wherein The flame-retardant resin composition as described. The flame retardant resin according to any one of claims 1 to 4 , wherein (A) the thermoplastic resin is a resin containing (A1) a polyolefin-based resin and / or (A2) a thermoplastic elastomer. Composition. (A) The thermoplastic resin is selected from an ethylene / unsaturated carboxylic acid ester copolymer, an ethylene / vinyl ester copolymer, and an ethylene / α-olefin copolymer having a density of 0.86 to 0.94 g / cm ^3. has been at least one ethylene copolymer (A1) according to claim 5, characterized in that the resin containing polyolefin resin 100 to 20 wt% and the (A2) 0 to 80 wt% thermoplastic elastomer Flame retardant resin composition. The flame retardant resin composition according to any one of claims 1 to 6 , further comprising (C) a functional group-containing polyolefin resin in an amount of 1 to 30% by mass based on (A) the thermoplastic resin. An electric wire or cable using the flame retardant resin composition according to any one of claims 1 to 7 .