JP2000186195A - Flame retarded insulation sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject sheet excellent in heat resistance and flame retardancy, not containing a flame retardant or the like including a halogen as an essential component, and useful as an insulation sheet for an electric or electronic equipment or the like by constituting the sheet of a composition comprising a polyphenylene ether-based resin, a phosphoric acid ester-based compound and the like. SOLUTION: This flame retarded insulation sheet is composed of a composition comprising (A) a polyphenylene ether-based resin preferably having 0.40-0.6 dl/g intrinsic viscosity measured in chloroform at 30 deg.C, such as poly(2,6- dimethyl-1,4-phenylene ether), (B) a phosphoric acid ester-based compound such as triphenyl phosphate, (C) preferably a dispersing element having <=100 μm maximum distance between both ends and >=2 aspect ratio (preferably polyorganosiloxane or the like), preferably regulated so that the amount of the component B based on 100 pts.wt. component A may be 2-65 pts.wt., and the proportion of the component C based on the total amount of the composition may be 0.3-10 wt.%. The sheet has preferably <0.5 mm thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flame-retardant insulating sheet. More specifically, the present invention relates to a flame-retardant insulating sheet using a polyphenylene ether-based resin composition, which is excellent in heat resistance and flame retardancy, and contains a halogen-containing flame retardant or a halogen-containing drip preventing agent. The present invention relates to a flame-retardant insulating sheet which does not contain as an essential component.

[0002]

2. Description of the Related Art Flame-retardant insulating sheets for electric and electronic parts are sheets having a thickness of about 0.1 to 0.5 mm, and are required to have excellent heat resistance in addition to excellent flame retardancy and insulation properties. ing. Although a vinyl chloride-based resin sheet is frequently used as such a flame-retardant insulating sheet, in recent years, the effect of halogen contained in the resin on the environment has been considered a problem. Demands are growing. Further, a thin sheet such as a flame-retardant insulating sheet is liable to cause an undesired phenomenon (hereinafter, referred to as “drip phenomenon”) in which a fire is dropped when the sheet is burned. This phenomenon is more likely to occur as compared to a sheet containing.

As a technique for improving the drip phenomenon of polyphenylene ether resin, for example, US Pat.
No. 7,232, U.S. Pat. No. 4,332,714 and U.S. Pat. No. 4,355,512 disclose a technique using polyfluoroethylene in combination.

However, polyfluoroethylene is
Since it contains a halogen like the above-mentioned vinyl chloride resin, it has an environmental problem.

[0005]

SUMMARY OF THE INVENTION Under such circumstances, an object of the present invention is to provide a flame-retardant insulating sheet using a polyphenylene ether-based resin composition, and a flame-retardant containing halogen, An object of the present invention is to provide a flame-retardant insulating sheet which does not include a drip inhibitor containing halogen as an essential component.

[0006]

The present inventors have conducted intensive studies on the heat resistance and flame retardancy of the polyphenylene ether-based resin composition, and found that the polyphenylene ether-based resin composition contained in a matrix formed from the polyphenylene ether-based resin and the phosphate compound. The present inventors have found that the above problems can be solved by the presence of a dispersion having a specific aspect ratio, and have completed the present invention. That is, the present invention provides the following (A):
The present invention relates to a flame-retardant insulating sheet made of a resin composition containing (B) and (C). (A): polyphenylene ether resin (B): phosphate compound (C): dispersion having an aspect ratio of 2 or more

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION (A) of the present invention is a polyphenylene ether resin. The polyphenylene ether-based resin is obtained by oxidatively polymerizing one or more phenol compounds represented by the following general formula (I) with oxygen or an oxygen-containing gas using an oxidation coupling catalyst (co).
It is a polymer. (Wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each selected from a hydrogen atom, a halogen atom, a hydrocarbon group or a substituted hydrocarbon group, and one of them is always a hydrogen atom Is.)

Specific examples of R ₁ , R ₂ , R ₃ , R ₄ and R _{5 in} the above general formula include hydrogen, chlorine, bromine, fluorine,
Iodine, methyl, ethyl, n- or iso-propyl,
pri-, sec- or t-butyl, chloroethyl, hydroxyethyl, phenylethyl, benzyl, hydroxymethyl, carboxyethyl, methoxycarbonylethyl, cyanoethyl, phenyl, chlorophenyl, methylphenyl, dimethylphenyl, ethylphenyl, allyl, etc. .

Specific examples of the above general formula include phenol, o-, m- or p-cresol, 2,6-, 2,5
-, 2,4- or 3,5-dimethylphenol, 2-methyl-6-phenylphenol, 2,6-diphenylphenol, 2,6-diethylphenol, 2-methyl-
6-ethylphenol, 2,3,5-, 2,3,6- or 2,4,6-trimethylphenol, 3-methyl-6
-T-butylphenol, thymol, 2-methyl-6
Allylphenol and the like can be mentioned. Further, phenol compounds other than the above general formula, for example, bisphenol-
A, a polyvalent hydroxyaromatic compound such as tetrabromobisphenol-A, resorcinol, hydroquinone, and a novolak resin, and a phenol compound represented by the above general formula may be used as raw materials for the copolymer. Among these compounds, 2,6-dimethylphenol, 2,6-diphenylphenol, 3-methyl-6-t-butylphenol and 2,3,6-trimethylphenol are preferred.

The oxidative coupling catalyst used in the oxidative polymerization of the phenol compound is not particularly limited, and any catalyst having a polymerization ability can be used.

The method for producing such a polyphenylene ether resin is described, for example, in US Pat. Nos. 3,306,874, 3,306,875 and 3,257,357, JP-B-52-17880, and JP-A-50-5.
No. 1197, JP-A-1-304119 and the like.

Specific examples of the polyphenylene ether-based resin in the present invention include poly (2,6-dimethyl-1,1).
4-phenylene ether), poly (2,6-diethyl-
1,4-phenylene ether), poly (2-methyl-6)
-Ethyl-1,4-phenylene ether), poly (2-
Methyl-6-propyl-1,4-phenylene ether), poly (2,6-dipropyl-1,4-phenylene ether), poly (2-ethyl-6-propyl-1,4)
-Phenylene ether), poly (2,6-dibutyl-)
1,4-phenylene ether), poly (2,6-dipropenyl-1,4-phenylene ether), poly (2,6
-Dilauryl-1,4-phenylene ether), poly (2,6-diphenyl-1,4-phenylene ether), poly (2,6-dimethoxy-1,4-phenylene ether), poly (2,6-diethoxy) -1,4-phenylene ether), poly (2-methoxy-6-ethoxy-1,4-phenylene ether), poly (2-ethyl-
6-stearyloxy-1,4-phenylene ether), poly (2-methyl-6-phenyl-1,4-phenylene ether), poly (2-methyl-1,4-phenylene ether), poly (2-ethoxy) -1,4-phenylene ether), poly (2-chloro-1,4-phenylene ether), poly (3-methyl-6-t-butyl-)
1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether), poly (2,5-dibromo-1,4-phenylene ether), poly (2,6
-Dibenzyl-1,4-phenylene ether) and various copolymers containing a plurality of repeating units constituting these polymers. Some copolymers have 2,
Copolymers of polysubstituted phenols such as 3,6-trimethylphenol and 2,3,5,6-tetramethylphenol with 2,6-dimethylphenol are also included. Among these polyphenylene ether resins, preferred are poly (2,6-dimethyl-1,4-phenylene ether) and a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol.

The polyphenylene ether resin used in the present invention is styrene, α-
A copolymer modified by grafting a styrene compound such as methylstyrene, p-methylstyrene, vinyltoluene and chlorostyrene may be used.

The polyphenylene ether resin usable in the present invention preferably has an intrinsic viscosity of 0.3 to 0.7 dl / g measured in chloroform at 30 ° C., more preferably 0.36 to 0.65 dl / g. g, most preferably 0.40 to 0.6 dl / g. If the intrinsic viscosity is too low, it may be difficult to achieve no dripping (drip phenomenon does not occur) during combustion, while if the intrinsic viscosity is too high, the moldability may decrease. Here, "no dripping" means that the burning sample does not drop in the UL94 vertical flammability test, which is a test method for flame retardancy.

The component (B) of the present invention is a phosphate compound. The phosphate compound is generally represented by the following general formula (II), but is not limited thereto. (Wherein, R _{6 to} R ₉ each independently represent a hydrogen atom or an organic group, except for the case where R ₆ ＝ R ₇ ＲR ₈ ＲR ₉ ＨH. X is a divalent organic group And p is 0 or 1, and q
Is an integer of 1 or more, and r represents an integer of 0 or more. )

The organic groups represented by R ₆ , R ₇ , R ₈ and R ₉ include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms and an aryl group having 6 to 20 carbon atoms, and 1 carbon atom. ~
20 alkoxy groups can be exemplified. These groups may be substituted, in which case, as a substituent,
Examples thereof include an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, and a hydroxyl group. Further, as the substituent, a group obtained by combining the above substituents (for example, an arylalkoxyalkyl group) or a group obtained by bonding the above substituents by an oxygen atom, a sulfur atom, a nitrogen atom, or the like (for example, an arylsulfonylaryl group) Can be exemplified.

Specific examples of R ₆ , R ₇ , R ₈ and R ₉ include:
Methyl, ethyl, propyl, butyl, pentyl, octyl, dodecyl, ethylhexyl, trimethylhexyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, tolyl, xylyl, nonyl A phenyl group, a naphthyl group and a butoxyethyl group can be mentioned, and among them, a phenyl group, a tolyl group and a xylyl group are preferred.

As the divalent organic group X of the formula (II), an alkylene group derived from an alkyl group having 1 to 20 carbon atoms; a phenylene group derived from a phenyl group having or not having a substituent; bisphenol And the groups derived from the polynuclear phenols exemplified by the above groups. Of these, the latter two groups are preferred. As particularly preferred X, groups derived from hydroquinone, resorcinol, bisphenol A and the like can be exemplified.

Specific examples of component (B) include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, phenylbisdodecyl phosphate, phenylbisneopentyl phosphate, and phenyl phosphate. Bis (3,5,5-trimethylhexyl), ethyl diphenyl phosphate, bis (2-ethylhexyl) phosphate (p-tolyl), tritolyl phosphate, bis (2-ethylhexyl) phenyl phosphate, tri (nonyl) phosphate Phenyl), triphenyl phosphate, dibutylphenyl phosphate, -p-tolylbis phosphate (2,5,5-
Trimethylhexyl), 2-ethylhexyldiphenyl phosphate, bisphenol A bisdiphenylphospho-
Bisphenol A bisdicresyl phosphate, bisphenol A bisdicylyl phosphate, hydroquinone bisdiphenyl phosphate, hydroquinone bisdicresyl phosphate, hydroquinone bisdicylyl phosphate , Resorcinol bisdiphenyl phosphate, resorcinol bisdicresyl phosphate, resorcinol bisdixylyl phosphate.

Two or more types of component (B) may be used in combination. In this case, from the viewpoint of the balance between the heat resistance and the flame retardancy of the resulting polyphenylene ether-based resin composition, in particular, the formula (II) It is preferable to use a non-condensation type phosphate compound having r of 0 and a condensation type phosphate compound having r of 1 or more in combination. r
As the non-condensation type phosphoric ester compound wherein is 0, tolyl phosphate and triphenyl phosphate are preferred. Examples of the condensed-type phosphate compound in which r is 1 or more include bisphenol A bisdiphenyl phosphate and bisphenol A bisdixylyl phosphate.
, Resorcinol bisdiphenyl phosphate and resorcinol bisdixylyl phosphate are preferred.

The content of the component (B) in the polyphenylene ether-based resin composition of the present invention is 100 parts (A).
The amount is preferably 1 to 70 parts by weight, more preferably 2 to 65 parts by weight based on parts by weight. If the amount of the component (B) is too small, the resulting polyphenylene ether-based resin composition may have insufficient flame retardancy, and if it is too large, the heat resistance of the resin composition may be insufficient. .

The dispersion of the component (C) used in the present invention means a component which is not compatible with the components (A) and (B) (cannot be mixed uniformly). Are dispersed in a continuous phase (matrix) composed of component (A) and component (B) to form a dispersed phase. Examples of the dispersion include an inorganic filler, a liquid crystal polymer, and a polyorganosiloxane.

As inorganic fillers, calcium silicate, magnesium silicate, reinforcing fibers (glass fibers, carbon fibers, aramid fibers, fibers made of aluminum or stainless steel), metal whiskers, silica, alumina, calcium carbonate, wollastonite, talc , Mica, clay,
Kaolin can be exemplified.

The liquid crystal polymer means a polymer exhibiting liquid crystallinity in a molten state. The polymer is characterized in that it has a higher heat deformation temperature than the component forming the continuous phase of the polyphenylene ether-based resin composition of the present invention, and is easily oriented in a fibril form in a matrix.

Examples of the liquid crystal polymer include Vectra A950 (trade name) manufactured by Polyplastics Co., Ltd., Econol 6000 (trade name) manufactured by Sumitomo Chemical Co., Ltd., and Zyda (trade name) manufactured by Nippon Petrochemical Co., Ltd. ) And thermoplastic LC polyesters exemplified by Rodrun LC3000 and LC5000 (trade name) manufactured by Unitika Co., Ltd.

The polyorganosiloxane is represented by the following formula (II)
At least one selected from I), formula (IV) and formula (V)
A compound having at least one kind of structural unit and a structural unit of the formula (VI). SiO _2.0 (III) R ₁₀ SiO _1.5 (IV) R ₁₁ R ₁₂ SiO _1.0 (V) R ₁₃ R ₁₄ R ₁₅ SiO _1.5 (VI) (R ₁₀ , R ₁₁ and R ₁₂ each independently have a carbon number 1
Represents an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R ₁₃ , R ₁₄ and R ₁₅ each independently represent an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms. ,
Represents an alkoxy group having 1 to 6 carbon atoms or a hydroxyl group. )

The formula (II) relating to polyorganosiloxane
With respect to the structural units represented by I), (IV), (V) and (VI), the formula (III) represents a tetravalent structural unit representing a non-terminal portion of the molecule, and the formula (IV) represents a non-terminal portion of the molecule. The formula (V) represents a divalent structural unit representing a non-terminal portion of the molecule, and the formula (VI) represents a monovalent structural terminal representing a terminal portion of the molecule.

Therefore, a polyorganosiloxane comprising only the structural units of the formulas (V) and (VI) forms a linear structure. Further, the polyorganosiloxane having the structural unit of the formula (III) or (IV) forms a branched structure.

R in formulas (III), (IV) and (V)
In _10, R ₁₁ and R _12, preferred alkyl groups are methyl group, preferred aryl group is phenyl group.

In R ₁₃ , R ₁₄ and R ₁₅ in the formula (VI), a preferred alkyl group is a methyl group, a preferred aryl group is a phenyl group, and a preferred alkoxy group is a methoxy group.

Specific examples of the polyorganosiloxane include a linear polydimethylsiloxane comprising the structural units of the formulas (V) and (VI); a polydimethylsiloxane in which a part of the methyl group of the polydimethylsiloxane is substituted by a phenyl group. Organosiloxane; polymethylsiloxane having a branched structure composed of structural units of the formulas (IV), (V) and (VI); polymethylsiloxane having a branched structure in which a part of methyl groups of the polymethylsiloxane is substituted by a phenyl group And organosiloxanes. When the polyorganosiloxane contains a phenyl group as R ₁₀ , R ₁₁ and R ₁₂ , R ₁₀ , R ₁₁
And the ratio of the phenyl group to the sum of R ₁₂ is 30 to 7
It is preferably 0 mol%.

The polyorganosiloxane may be used in combination with silica. Among them, a powdery mixture composed of polydiorganosiloxane and silica is preferred. As polydiorganosiloxane used in combination with silica, 10 Pa · s to 100000 Pa at 25 ° C.
• A polydiorganosiloxane having a viscosity of s is preferred.

Silica is fumed silica or precipitated silica.
Finely divided from mosquito or silica aerosol
Silica. As silica, the surface area is 50-40.
0m ^Two/ G is preferred. Silica is silano
Contains a precursor of a hydroxyl group or a hydrolyzable silanol group
Liquid organosiloxane compound (hereinafter referred to as silica treatment)
Agent). Said,
As the silica treating agent, a hydroxy group or an alkoxy group
Low-molecular-weight liquid polydiorganosiloxy terminated with a silyl group
Sun, hexaorganodisiloxane, hexaorganodi
Silazane and the like are exemplified. Preferred as silica treatment agent
Is a polymer having an average polymerization degree of hydroxy terminal of 2 to 10.
Tylsiloxane oligomer. Silica is a polyol
100 weight on silica before blending with ganosiloxane
10 to 45 parts by weight of silica treating agent
Preferably.

Further, it is preferable to further treat the powdery mixture of polyorganosiloxane and silica with an alkoxysilane compound. The alkoxysilane compound is a compound having at least one alkoxy group having 1 to 4 carbon atoms and at least one group selected from epoxy, amine, acryloxy, methacryloxy, vinyl, and phenyl.

When a polyphenylene ether-based resin composition (especially a thin molded article) is required to have excellent tensile elongation and impact resistance, a polyorganosiloxane or a mixture of polyorganosiloxane and silica is used as the component (C). Is preferred.

The aspect ratio of the dispersion in the polyphenylene ether-based resin composition of the present invention is 2 or more. The aspect ratio is t / d when the average value of the longest both-end distances of the dispersion existing in the sheet molding is t, and the average value of the shortest both-end distances is d. The average value of the distance between both ends of the dispersion existing in the sheet molded product can be obtained by taking a cross-sectional photograph of the sheet molded product with a scanning electron microscope or a transmission electron microscope, and randomly extracting 20 or more currents from the photograph. They are extracted, the longest distance and the shortest distance are measured and averaged respectively. If the aspect ratio is less than 2, the effect of preventing the drip phenomenon (drip prevention effect) of the resulting polyphenylene ether-based resin composition may be poor. The drip prevention effect is better as the aspect ratio is larger, but when the aspect ratio is about 100 or more, problems such as poor appearance of a molded product obtained by molding the polyphenylene ether-based composition occur. There is.

The longest distance between both ends of the component (C) is 100 μm in a molding method in which a tensile stress is applied to a free surface of a molten resin composition (for example, an extrusion molding method using a T-die). The following is preferred. 100 μm
If the length is longer than the above, irregularities may be generated on the surface of a molded article made of the obtained polyphenylene ether-based resin composition, and poor appearance may occur. In the case of molding methods such as injection molding, hot press molding, and calendar molding, the longest distance between both ends is 1
Even if it is longer than 00 μm, poor appearance hardly occurs.

The content of the component (C) is preferably from 0.2 to 20% by weight, more preferably from 0.3 to 10% by weight, based on the total weight of the polyphenylene ether-based resin composition. When the content of the component (C) is too small, the resulting polyphenylene ether-based resin composition may have a poor drip prevention effect. When the content is excessive, mechanical properties such as impact strength of the obtained polyphenylene ether-based resin composition may be obtained. May be inferior.

Each of the components constituting the polyphenylene ether-based resin composition of the present invention may be appropriately selected from other polymer compounds, dyes, pigments, antistatic agents, antioxidants, and the like as long as the effects of the present invention are not impaired. It may be used in combination with an additive exemplified by a weather resistance imparting agent and the like.

As other polymer compounds, polystyrene,
Styrene polymers exemplified by high impact polystyrene and styrene-butadiene-styrene triblock copolymer; polypropylene, high-density polyethylene, low-density polyethylene, linear low-density polyethylene, propylene-ethylene copolymer, ethylene-butene Olefin polymers exemplified by -1 copolymer, ethylene-pentene copolymer, ethylene-hexene copolymer and poly-4-methylpentene-1; olefins exemplified by ethylene and propylene; and acrylate esters Class (for example,
Methyl acrylate, ethyl acrylate), methacrylates (eg, methyl methacrylate, ethyl methacrylate), vinyl acetate, styrene, acrylonitrile and vinyl monomers exemplified by glycidyl (meth) acrylate Polymers: polymers such as polyvinyl chloride, polymethyl methacrylate, polyvinyl acetate, polyvinyl pyridine, polyvinyl carbazole, polyacrylamide, polyacrylonitrile; polycarbonate;
Polysulfone, polyether sulfone, polyethylene terephthalate, polybutylene terephthalate, polyarylene ester (for example, U-polymer (trade name) manufactured by Unitika Ltd.), polyphenylene sulfide, 6-nylon, 6,6-nylon, 12-nylon, etc. And high-molecular compounds such as polyamides and polyacetals; thermosetting resins such as polyimides, polyamideimides, phenol resins, alkyd resins, unsaturated polyester resins and diallyl phthalate resins; silicone resins and fluorine resins.

The method for producing the polyphenylene ether-based resin composition of the present invention is not particularly limited, and may be a known method. Examples of the production method include a solution blending method and a melt kneading method, and the melt kneading method is preferable. As a specific production method, after mixing each component in a mixer such as a Henschel mixer, a super mixer or a ribbon blender in an arbitrary order, the mixture is used as a Barry mixer, a plast mill, a Brabender, or a single or twin screw extruder. And a method of melt-kneading with a kneader. The melt-kneading temperature is usually 150 to 400 ° C., preferably 20 to 400 ° C.
0-350 ° C.

The method for producing the molded article comprising the polyphenylene ether-based resin composition of the present invention is not particularly limited, and may be a known method. Examples of the method for producing the molded article include extrusion molding, calender molding, injection molding, and blow molding. Molding and the like can be exemplified.

The use of the flame-retardant insulating sheet of the present invention is as follows.
For example, there is an insulating sheet application for OA equipment, electric and electronic equipment. In particular, it is required that the sheet having a heat deformation temperature of 80 ° C. or more under a load of 18.6 kgf and a thickness of less than 0.5 mm has a flame retardancy of V-0 in a UL flame retardancy test. It can be optimally used as an insulating sheet.

[0044]

The present invention will be described in more detail with reference to the following examples.
Although described, the present invention is limited to these examples.
There is no. Indicates the meaning of the abbreviation used.PPE (Component (A)): Polyphenylene ether-based resin
(Intrinsic viscosity measured at 30 ° C in chloroform solvent
0.46 dl / g of poly (2,6-dimethyl-1,4-
Phenylene ether))SBS (Other polymer compound): styrene-butadiene-
Styrene triblock copolymer (C manufactured by Shell Chemical Company)
ARIFLEX TR1101)P-1 (Component (B)): triphenyl phosphate (Daiwachi Chemical)
Industrial company)P-2 : (Component (B)) resorcinol bisdiphenyl
Phosphate (CR733S manufactured by Daihachi Chemical Industries, formula (I
R in I)₆, R₇, R₈And R₉Is a phenyl group, X is
Phenylene group, p = 1, q = 1, r = 1 compound)Zonoheidi (Component (C)): 6 made by Ube Materials
CaO ・ 6SiO ・ H _TwoAn inorganic filler having a chemical formula of O
Ra.Wollastonite (Component (C)): Hayashi Kasei's inorganic filler
Ra.GF (Component (C)): TP35 manufactured by Nippon Sheet Glass Co., Ltd.LCP (Component (C)): Liquid crystal polymer manufactured by Unitika
Rod Run LC5000SIP (Component (C)): Dow Corning Asia D
C4-7051 (Epoxy group-containing alkoxysila
Mixed with silica, silica, and polydiorganosiloxane
Compound)

The method for evaluating physical properties is as follows. (1) Heat Deformation Temperature (HDT) The heat distortion temperature as a measure of heat resistance is defined as ASTM D
According to 648, it was measured under a load of 1.81 MPa. (2) Tensile Elongation Tensile elongation at 23 ° C. was measured according to ASTM D638. (3) Izod Impact Strength Notched Izod impact strength at 23 ° C. was measured according to ASTM D256. (4) Flame retardancy A UL94 vertical flammability test was performed using test pieces having a thickness of 0.4 mm and 0.3 mm obtained by press-molding the polyphenylene ether-based resin composition. "Not applicable" in the evaluation of flame retardancy means "the burning time is longer than a specified time" or "the test piece burns up to the clamp", and is inferior to V-0, V-1 and V-2. It is evaluation. (5) Appearance Polyphenylene ether-based resin composition is screwed with a screw diameter of 3
0.3mm thickness obtained by molding with a 0mm single screw extruder
Was visually observed, and the appearance was evaluated according to the following criteria. ：: No appearance defect ×: Appearance defect (6) Aspect ratio Regarding the aspect ratio when the dispersion is an inorganic filler, a molded product having a thickness of 0.3 mm obtained by press molding a polyphenylene ether-based resin composition. From the scanning electron micrograph of the cross section, 20 or more dispersions were randomly extracted, the longest and shortest end distances of each dispersion were measured, and the aspect ratio (aspect ratio ( Average value of the longest both-end distance / average value of the shortest both-end distance). Regarding the aspect ratio when the dispersion is a liquid crystal polymer, an ultra-thin section cut out from a press molded body made of a polyphenylene ether-based resin composition with a microtome was stained with osmium tetraoxide, and from this transmission electron micrograph. , Randomly extracting more than 20 dispersions,
The longest end distance and the shortest end distance of each dispersion were measured, and the aspect ratio (the average value of the longest end distance / the average value of the shortest both end distances) was determined from the average value. Regarding the aspect ratio when the dispersion is a silicon compound, the transmission electron micrograph of an ultra-thin section (unstained) cut out from a press molded body made of a polyphenylene ether-based resin composition with a microtome shows that at least 20 dispersions were obtained. Randomly extract the body, measure the longest end distance and the shortest end distance of each dispersion, and calculate the aspect ratio (the average of the longest end distance / the average of the shortest end distance) from each average value. Was.

Example 1 Each component having the mixing ratio shown in Table 1 was used at a cylinder temperature of 260
The mixture was poured from a hopper of a continuous twin-screw kneader (TEM-50A, manufactured by Toshiba Machine Co., Ltd.) set at 200 ° C. and a screw rotation speed of 200 rpm, melt-kneaded, and pelletized. 26 pellets
Press molding was performed at 0 ° C. to produce test pieces having a thickness of 0.4 mm and 0.3 mm. The evaluation results are shown in Tables 1 and 2.
Further, using a single screw extruder having a screw diameter of 30 mm, a T-die having a lip width of 0.5 mm was used to prepare a sheet having an extrusion temperature of 260 ° C. and a thickness of 0.3 mm, and the appearance was visually evaluated.

Examples 2 to 6 and Comparative Examples 1 and 2 Except for using each component at the compounding ratio shown in Tables 1 and 3,
It carried out similarly to Example 1. The evaluation results are shown in Tables 1, 2, 3 and 4.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

[Table 4]

[0052]

As described above, according to the present invention, there is provided a flame-retardant insulating sheet using a polyphenylene ether-based resin composition, wherein a halogen-containing flame retardant and a halogen-containing drip preventing agent are essential components. A non-flammable insulating sheet can be provided.

Claims (6)

[Claims] 1. A flame-retardant insulating sheet comprising a resin composition containing the following (A), (B) and (C). (A): polyphenylene ether resin (B): phosphate compound (C): dispersion having an aspect ratio of 2 or more 2. The flame-retardant insulating sheet according to claim 1, wherein (C) is an inorganic filler having an aspect ratio of 2 or more. 3. The flame-retardant insulating sheet according to claim 1, wherein (C) is a polyorganosiloxane. 4. The flame-retardant insulating sheet according to claim 1, wherein (C) is a polyorganosiloxane and silica. 5. The flame-retardant insulating sheet according to claim 2, wherein the longest both ends distance of (C) is 100 μm or less. 6. The flame-retardant insulating sheet according to claim 1, wherein the thickness of the sheet is less than 0.5 mm.