JP2547802B2 - Composition for composite type damping material - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a composite vibration damping material composition, and more specifically, constitutes a constituent member of a vehicle, an electric component, a machine or a structure, or a part thereof. Thus, the present invention relates to a composition used in the form of a film when producing a composite vibration damping material having a high vibration absorbing performance capable of reducing these vibrations and reducing noise.

[Conventional technology]

In recent years, the problems of noise and vibration have become a social problem as pollution due to the development of transportation facilities and the approach of factories to houses, and noise and vibration are regulated in the workplace for the purpose of improving the working environment. Tend to do. In response to such a trend, it is required to add vibration damping performance to a metal material that is a noise source or a vibration source and to improve the vibration damping performance.

Therefore, as one of the materials exhibiting such damping performance, a composite damping material having a three-layer structure in which a viscoelastic intermediate layer made of a viscoelastic resin is sandwiched between two metal layers has been proposed. Cages such as automobile oil pans, engine covers, dashboard panels and floors, hopper chute parts, transport equipment stoppers, home appliances,
In addition, it has been studied and adopted as a vibration reducing member of metal working machines and a structural member of precision machines for which vibration prevention is desired.

In this case, as the metal material forming the two metal layers, any metal material may be used as long as it can face each other and sandwich a viscoelastic resin in the middle to form a vibration damping material, for example, two metal plates, two metal plates. Examples thereof include a concentric metal tube, two shaped steels, two molded bodies that can be stacked on each other, a metal molded body and a contact plate, and other materials having a two-layer structure. The metal forming the metal layer is not particularly limited, but is usually iron, aluminum,
It may be copper, lead, or an alloy containing one of these components, or a metal material plated with zinc, tin, chromium or the like, and one surface-treated with an epoxy resin, a melamine resin or the like.

As a viscoelastic resin that constitutes the viscoelastic intermediate layer of such a composite damping material, polyamide (Japanese Patent Laid-Open No. 56-15
9,160), ethylene-vinyl acetate copolymer (JP-A-57-34,949), polyester resin or resin composition of polyester resin and polyolefin resin (JP-A-61-89,842), vinyl Composition of incompatible amorphous thermoplastic polymer having different glass transition temperatures such as a composition of ester or acrylic polymer and styrene polymer (JP-A-60-258,262), vinyl-based composition A composition composed of an amorphous thermoplastic polymer such as a polymer (JP-A-61-28551), or a resin composition composed of an amorphous polyester resin and a low crystalline polyester resin by the present inventors. Compositions based on various resin systems such as Japanese Patent Application No. 62-18160 are proposed. Further, a mixture of polyvinyl butyral or a mixture of polyvinyl butyral and polyvinyl acetate with a plasticizer and a tackifier (Japanese Patent Publication No. 55-27,975), a copolymer of an isocyanate prepolymer and a vinyl monomer (Japanese Patent Publication No. No. 52-26554), a composition obtained by mixing a saturated polyester resin with an organic peroxide as a cross-linking agent and a filler (Japanese Patent Publication No. 53-9794) is proposed. Further, a resin structure such as an olefin-based resin multilayer body (JP-A-60-82,349) has also been proposed.

By the way, as a characteristic required for such a composite type vibration damping material, first, it is mentioned that the vibration damping performance is high, and this is generally expressed by the magnitude of the loss coefficient. Secondly, since the composite vibration damping material is also used as a structural member and undergoes secondary processing such as pressing, adhesion between the viscoelastic intermediate layer composed of viscoelastic resin and the outer metal layer It can be mentioned that the strength, especially the shear adhesive strength, is high. Further, the composite type vibration damping material is sometimes used even at around 80 ° C., so that the shear adhesive strength at 80 ° C. is required to some extent. Furthermore, thirdly, the composite type vibration damping material subjected to the press processing may undergo a baking coating step of heating up to about 200 ° C., and it is also required that the intermediate layer resin composition does not flow out near this temperature. .

On the other hand, as a method for producing a composite type vibration damping material by compounding a viscoelastic resin and a metal material, a method of applying a paint-like material in which a viscoelastic resin is dissolved in a solvent to a metal material and bonding them together, T- Examples thereof include a method of forming an intermediate layer of viscoelastic resin on a metal material with a die extruder or the like, a method of sandwiching a film-shaped viscoelastic resin produced off-line as an intermediate layer between metal materials and performing hot melt adhesion, and the like. Although these methods have their respective losses, it is preferable to use a film-like viscoelastic resin in consideration of the work system for compounding, the work environment, the stability of product management, and the like.

The viscoelastic resin composition can be formed into a film by using an ordinary film forming process, and is not particularly limited, but the film can be formed at a temperature below the temperature at which the melt viscosity of the viscoelastic resin composition causes thermal decomposition. It must have a thermoplasticity that decreases until

In particular, in the case of a vibration damping material that exhibits excellent vibration damping performance in the normal temperature range of 0 to 60 ° C, the glass transition region of the viscoelastic intermediate layer resin composition needs to be around normal temperature or lower, and elasticity at normal temperature It is a composition with a low rate. On the other hand, the shear adhesive strength, which has an important influence on the press workability, is generally superior to the composition showing a high elastic modulus. That is, the vibration damping performance required for the composite type vibration damping material and the shear adhesive strength related to the press workability are contradictory requirements regarding the elastic modulus of the viscoelastic intermediate layer resin. A composite type vibration damping material manufactured by using a material cannot satisfy both of these properties sufficiently, and is not sufficient as a viscoelastic composition for a vibration damping material. A blend of a thermoplastic resin and an amorphous plastic resin is not satisfactory even though the damping performance can be satisfied, but the adhesive strength and mechanical strength are poor due to the incompatibility of different polymers. It was

Further, the amorphous polyester-based resin is known to be a resin having excellent adhesiveness to a metal material, but it has a glass transition temperature of such that it exhibits vibration damping performance particularly at room temperature. In the case of a low resin, the shear adhesive strength does not show a value high enough to withstand press working, so that it cannot be said to be a satisfactory material.

Furthermore, even with a composition comprising a polyester resin, an organic peroxide cross-linking agent, and a filler disclosed in JP-B-53-9,794, although the shear adhesive strength is improved, the obtained damping material is resistant to press working. It does not show a high enough value. Further, it is difficult to control the crosslinking reaction of the polyester resin with a crosslinking agent that generates a radical such as an organic peroxide, and the radical reaction occurs anywhere in the terminal, main chain or side chain of the polyester resin, and It suppresses molecular motion and adversely affects vibration damping performance.

On the other hand, in the case of a composition composed of an amorphous polyester resin, an acid anhydride and an epoxy compound proposed in Japanese Patent Application No. 61-219,160, it exhibits excellent vibration damping performance in the normal temperature range, and also has a shear adhesive strength for press working. The value is high enough to withstand, but if the blending amount of the acid anhydride and the epoxy compound is large, the fluidity of the resin composition is lowered and the film forming becomes difficult. Further, when a high compounding amount of the acid anhydride and the epoxy compound is used, it is necessary to apply the resin composition to the steel sheet as a paint type in the manufacturing process of the composite type vibration damping material and then carry out the cross-linking reaction, which is complicated. Is hard to avoid.

Further, a resin composition comprising a blend of an amorphous polyester resin and a low-crystalline polyester resin proposed in Japanese Patent Application No. 62-18160 shows a sufficient vibration damping performance and shear adhesive strength at room temperature, The fluidity increases extremely at high temperature
At about 200 ° C, the outer metal layer might open, and the shear adhesive strength at 80 ° C was low, and it was not sufficiently satisfactory as a composite damping material.

[Problems to be solved by the invention]

The present invention was devised in view of such a viewpoint and can be preliminarily formed into a film, and has excellent adhesiveness to a metal material from room temperature to around 80 ° C, which imparts excellent vibration damping performance at room temperature, It is an object of the present invention to provide a composition suitable for producing a composite damping material capable of forming a viscoelastic intermediate layer that does not easily flow out even near the coating baking temperature.

[Means for solving problems]

That is, the present invention relates to 100 parts by weight of a thermoplastic saturated polyester resin having a glass transition temperature of −30 to 60 ° C. and a loss tangent of 0.5 or more at this glass transition temperature, and an acid anhydride in an amount of 0.05 to less than 1 part by weight. A film composition for producing a composite damping material, which comprises 0.05 to 10 parts by weight of an epoxy compound having two or more epoxy groups in one molecule.

First, the composite damping material in the present invention has a so-called three-layer structure in which a viscoelastic intermediate layer for joining these metal layers to each other is sandwiched between two metal layers as described above. The viscoelastic resin composition for forming the viscoelastic intermediate layer is further formed on the film.

The thermoplastic polyester resin that constitutes this viscoelastic resin composition is one that exhibits vibration damping performance at room temperature.
A viscoelastic resin composition having a glass transition temperature at 60 ° C. When the glass transition temperature is lower than -30 ° C, the glass transition temperature of -30 to 60 which is usually required for the composition for composite type damping material is obtained.
In order to shift the glass transition temperature to ℃, it is necessary to add a large amount of high melting point solid resin, filler, etc.
On the contrary, when the temperature is higher than 0 ° C, it is necessary to add a large amount of plasticizer in order to shift the glass transition temperature to the low temperature side. When a large amount of these various additives is used, the adhesiveness may be lowered, and it may be liable to flow at high temperature, which is not preferable. In addition, the loss tangent (tan
δ) is 0.5 or more, preferably from the viewpoint of damping performance.
Must be 0.7 or higher. This loss tangent (tan
If δ) is less than 0.5, satisfactory vibration damping performance will not be exhibited.

As such a saturated polyester resin, a highly crystalline saturated polyester such as polyethylene terephthalate or polybutylene terephthalate is dissolved in ethylene glycol at high temperature to obtain a saturated polyhydric alcohol such as triethylene glycol, 1,4-butanediol or neopentyl glycol. It is possible to synthesize it by transesterification, and also by copolymerizing a saturated polyvalent carboxylic acid and a saturated polyhydric alcohol. Saturated polycarboxylic acids used in the latter synthetic method include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedione. Acid, trimellitic anhydride, etc. can be mentioned, and as the saturated polyhydric alcohol, ethylene glycol, 1,4-
Butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, polyethylene glycol, neopentyl glycol, propylene glycol, 1,4-cyclohexanedimethanol, pentaerythritol, trimethylolpropane, etc. be able to. There are many combinations of these monomers, and they are appropriately selected and used depending on the desired melting point, glass transition temperature, degree of amorphousness or crystallinity, and the like.

Further, the polyester resin used is not limited to one kind, and may be a composition in which two or more kinds of polyester resins are mixed. When two or more types are mixed, the loss tangent of the mixture is 0.5 when they show compatible behavior with each other.
If it is above, it is good. In addition, when two or more kinds of polyethylene ester resins exhibit incompatible behavior, there are two or more maximum values of the loss tangent of the mixture, and the maximum value of them is the largest.
It should show 0.5 or more.

In addition, a resin other than the polyester resin may be mixed with this polyester resin in order to improve the vibration damping performance or the elastic modulus of the selected polyester resin. The resin other than the polyester resin is not particularly limited as long as it can be kneaded with the polyester resin by a usual method such as roll kneading, kneader kneading, and extruder kneading. As these resins, for example, polystyrene, AS resin, ABS resin, MS resin, styrene resin such as impact-resistant polystyrene, polymethyl acrylate,
Acrylic resin such as polymethylmethacrylate, polyethylmethacrylate, acrylic copolymer, vinyl chloride resin such as polyvinyl chloride, vinyl chloride / vinyl acetate copolymer, vinyl chloride / acrylic ester copolymer,
Vinyl acetate resins such as polyvinyl acetate, polyvinyl formal, polyvinyl butyral, ethylene / α-olefin copolymers, ethylene / vinyl acetate copolymers, ethylene / acrylic acid copolymers, ethylene / methacrylic acid ester copolymers ethylene -Ethylene-based resins such as metal cross-linked methacrylic acid copolymers, propylene-based resins such as propylene-ethylene copolymers, propylene-butene copolymers, and thermoplastic resins such as amorphous polyamides such as copolymerized nylon Can be illustrated. Further, elastomers such as styrene / butadiene rubber, natural rubber, butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, ethylene / acrylic rubber, EPDM and the like can also be mentioned.

Further, an acid anhydride and an epoxy compound are used together with the saturated polyester resin in order to improve the shear direct contact strength which affects the press working of the obtained vibration damping material,
As the acid anhydride, maleic anhydride, dodecenylsuccinic anhydride, chlorendecic anhydride, sebacic anhydride polymer, phthalic anhydride, pyromellitic dianhydride, cyclopentanetetracarboxylic dianhydride, hexahydrophthalic anhydride, methylhexahydro Phthalic anhydride, tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride,
5- (2,5-dioxotetrahydroxyfuryl) -3-
Methyl-cyclohexene-1,2-dicarboxylic acid anhydride,
Illustrative examples include mernadic acid anhydride and benzophenone tetracarboxylic acid anhydride.

These acid anhydrides may be used either individually or in combination of two or more, but in order to effectively crosslink the saturated polyester resin and develop excellent shear adhesive strength, at least 1 of the acid anhydride is used. The component is preferably a polyfunctional compound having two or more acid anhydride groups in one molecule.

The epoxy compound has two or more epoxy groups in one molecule, and is a bisphenol A-based epoxy resin, a tetrabromobisphenol A-based epoxy resin, a bisphenol F-based epoxy resin, a phenolvolac epoxy resin, Brominated phenol novolac epoxy resin, cresol novolac epoxy resin, tetraglycidyl metaxylenediamine, tetraglycidyl-1,3-bisaminomethylcyclohexane, tetraglycidyl diaminodiphenylmethane, triglycidyl-p
-Multifunctional glycidylamine compounds such as aminophenol, triglycidyl-m-aminophenol, diglycidylaniline, diglycidyl orthotoluidine, 1,4-
Butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol polyglycidyl ether, sorbitol polyglycidyl ether, and other multifunctional glycidyl ether compounds, phthalic acid diglycidyl ester, hexahydrophthalic acid diglyceride Examples thereof include glycidyl ester compounds such as sidyl ester and trimellitic acid polyglycidyl ester. These epoxy compounds may be used alone or in combination of two or more.

The acid anhydride and the epoxy compound are used together with the saturated polyester resin, and the amount thereof is 0.05 to less than 1 part by weight, more preferably 0.1 to less than 1 part by weight, relative to 100 parts by weight of the saturated polyester resin. Further, the amount of the epoxy compound having two or more epoxy groups in one molecule is 0.05 to 10 parts by weight, more preferably 0.1 to 10 parts by weight. Acid anhydride,
When the epoxy compound is lower than the above lower limit, the adhesive strength,
In particular, the shear adhesive strength is not improved so much, and the effect of adding the above-mentioned compound is small. Further, when the acid anhydride and the epoxy compound are higher than the above upper limit values, the shear adhesive strength is remarkably improved, but the vibration damping performance is extremely lowered, and it is preferable as a composition for use in the production of a vibration damping material in a film form. Absent. Further, in order to use it in the form of a film further, it is necessary to have thermoplasticity, and when the acid anhydride and the epoxy compound are higher than the above upper limit values, the melt viscosity at a high temperature when heated of the composition is remarkably increased, which makes film forming difficult. Inappropriate.

Further, in order to improve the adhesive strength without deteriorating the vibration damping performance due to the saturated polyester resin, the amount of the acid anhydride and the epoxy compound blended in the saturated polyester resin is adjusted to a molar ratio of epoxy group / acid anhydride group. Is preferably 0.5 to 5, and more preferably 0.5 to 4. The optimum blending degree depends on the molecular weight of the saturated polyester resin, the type of terminal functional group, and the types of acid anhydride and epoxy compound used together.

In the composition of the present invention, the functional group at the terminal of the saturated polyester resin reacts with an acid anhydride and an epoxy compound to be finally crosslinked, thereby satisfying various physical properties such as adhesive strength and vibration damping performance. In this cross-linking reaction, it is necessary to select the reaction rate depending on the combination of acid anhydride and epoxy compound used and the mixed state or dispersed state of the composition, and various catalysts can be used to obtain an appropriate reaction rate. .

As such a catalyst, for example, Zn (BF ₄ ) ₂ , SnCl ₄ , KOH or the like as a reaction catalyst of a hydroxyl group and an epoxy group is used for the reaction of a carboxyl group with an epoxy group and the reaction of an acid anhydride group with an epoxy group. Examples include tertiary amines such as benzyldimethylamine, tributylamine, tris (dimethylamino) methylphenol, quaternary ammonium salts such as triethylbenzylammonium chloride, tetramethylammonium chloride, cetyltrimethylammonium bromide, and 2-methyl-4ethyl. Examples thereof include imidazole compounds such as imidazole and 2-methylimidazole. Also,
Examples of the reaction between the hydroxyl group and the acid anhydride group include imidazole compounds and ferric acetylacetone salts.

Further, an inorganic filler may be further filled in order to further improve the shear adhesive strength of the composition of the present invention. Such an inorganic filler needs to be one that does not thermally decompose at about 200 ° C., and examples thereof include carbon black, silica, alumina, clay, titanium oxide, zinc oxide, mica, graphite, and the like. It is desirable to use at least one kind of carbon black, silica and clay from the viewpoint that the effect of improving the adhesive strength is great.

On the other hand, the amount of the inorganic filler added is preferably 1 to 100 parts by weight, particularly 5 to 50 parts by weight, based on 100 parts by weight of the resin. If the addition amount is less than 1 part by weight, the sufficient effect of improving the shear adhesive strength cannot be obtained, and if the addition amount is more than 100 parts by weight, the fluidity of the resin composition decreases and film formation becomes difficult.

It is also possible to add and use a plasticizer in order to shift the glass transition temperature of the resin composition to a desired value. Examples of the plasticizer used for this purpose include polyester plasticizers, polyether ester plasticizers, phosphoric acid esters, epoxy plasticizers, phthalic acid diesters, sebacic acid diesters and other ester plasticizers, and trimellitate. Examples thereof include acid plasticizers and chlorinated paraffins, which are appropriately selected and used according to the polyester resin used.

On the contrary, to the polyester resin having a low glass transition temperature, it is possible to add a substance such as a solid resin having a melting point higher than the glass transition temperature to shift the peak characteristic temperature to the high temperature side. Examples of such solid resin include alkylphenol resin, terpene phenol resin, rosin, rosin ester, hydrogenated rosin ester, coumarone / indene resin, phenol-modified coumarone resin, petroleum resin, etc. Considering the compatibility and so on, it is selected appropriately and used.

Further, by adding a conductive solid substance as a filler to the viscoelastic composition, conductivity can be imparted, and the obtained damping material can be made into a spot-weldable material. As the conductive material used for such a purpose, metal such as stainless steel, zinc, tin, copper, brass and nickel is powdered,
Examples thereof include metallic substances processed into flakes, fibers, wires and the like. These conductive materials can be used alone or in combination of two or more. And, as these conductive substances, in order to express good conductivity with the metal material when manufacturing the composite damping material, in order to enable even more stable spot welding, the conductive substance Is preferably softer than the outer layer metal material. If the conductive material is in the form of powder, its maximum particle diameter, in the case of flakes, its maximum thickness, and in the case of fiber, its maximum diameter is the representative length of each. (L), in order to obtain better spot weldability, the ratio (L / T) of the representative length (L) to the thickness (T) of the intermediate resin layer of the composite damping material is 0.5 or more. It is preferably 0.8 or more, more preferably 1.0 or more.

The thickness of the film-formed product of the composition of the present invention is appropriately selected from the required vibration damping performance and the like, but from the viewpoint of vibration damping performance, it is preferably 10 μm or more, particularly preferably 20 μm or more. 300 μm from the viewpoint of press workability
The following is particularly preferable, 200 μm or less.

As a method for kneading the composition of the present invention, considering the dispersibility of the cross-linking agent and the inorganic filler in the polyester resin, there is no particular limitation as long as a suitable shearing force and temperature can be applied thereto. A pressure type kneader, a Banbury mixer, a single screw extruder, a twin screw extruder, etc. are mentioned.

The method for obtaining a film from the composition of the present invention is appropriately selected from the melt viscosity and elongation of the resin composition and is not particularly limited, and T-die extrusion molding, inflation molding, calender molding, hot melt coating and the like can be used. Can be mentioned.

Further, when the obtained film has tackiness at room temperature, a release paper or a base material such as polyolefin may be applied to this film.

The method for producing a composite damping material using the film obtained from the composition of the present invention is not particularly limited, and any method such as a batch method using a cutting plate and a continuous method using a coil is used. Can be taken. Also, there is no particular limitation on the method of adhering the metal material and the film, for example, by sandwiching the film between two metal materials and thermocompression bonding at a temperature appropriately set depending on the melting temperature of the film. It is possible.

〔Example〕

Hereinafter, the present invention will be described based on Examples and Comparative Examples. Films to be tested in these Examples and Comparative Examples were prepared by the method described below. The polyester resin shown in Table 1 was put into a pressure kneader, and the acid anhydride, epoxy compound and catalyst shown in Table 1 were sequentially added thereto.
A composition was obtained by kneading at 100 ° C to 180 ° C. 12 this kneaded mixture
A film having a thickness of 70 μm was produced on a T-die extrusion release paper at a die temperature of 0 ° C. to 170 ° C.

This film was sandwiched between two 0.8 mm-thick cold-rolled steel plates and heat-pressed at 180 ° C. for 1 minute to obtain a composite vibration-damping material having a viscoelastic resin intermediate layer having a thickness of 70 μm.

T-peel adhesion strength is 50 mm / based on JIS-K-6854 test method
Evaluated by the tensile speed of min, the shear adhesive strength is JIS-K-6850
Based on the test method, it is evaluated at a pulling speed of 5 mm / min, or the vibration damping performance is measured by measuring the loss coefficient (η), which represents the vibration absorption capacity, using the mechanical impedance method, and the maximum value of η (η _max ) and this η _max
Was evaluated by measuring the temperature (T _p ).

Table 1 shows the results of testing by sandwiching these films between steel plates.

In Comparative Examples 1 to 3 in which neither acid anhydride nor epoxy compound was added to Polyester A, or only one of them was added, the shear adhesive strength was as low as 40 to 65 kgf / cm ² , whereas the acid anhydride and epoxy compound were added as described above. In Examples 1 to 5 blended within the range, the shear adhesive strength was 120 to 150.
It has markedly increased to kgf / cm ² . The vibration-damping performance at this time was also no addition even if an acid anhydride or an epoxy compound was added. Comparative Example 1
The maximum value (η _max ) of the loss coefficient does not decrease to 1.0 and the temperature (T _p ) that gives the maximum value of this loss coefficient is 4 to 5
It only rises by ° C.

Moreover, saturated polyester resin of two shear bond strength also in Example 6 was used 130 kgf / cm ² and an acid anhydride, it has been significantly increased compared to 25 kgf / cm ² in Comparative Example 5 of the epoxy compound without additives, control Regarding the vibration performance, the maximum value of the loss coefficient (η _max ) did not decrease, and the temperature (T _p ) at which the maximum value of the loss coefficient was increased also increased by 5 ° C.

On the other hand, in Comparative Example 6 in which the addition amount of the acid anhydride and the epoxy compound was higher than the above-mentioned upper limits, the kneading with the saturated polyester resin was not possible, but the fluidity was extremely poor and the film formation was impossible.

[Effect of the Invention] The composition of the present invention can be easily formed into a film, and
It is sandwiched between two metal materials, and the obtained composite vibration damping material has excellent adhesiveness and exhibits excellent vibration damping performance at around room temperature, which is extremely useful industrially.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tokoro Tokai, Tokai-shi, Aichi 5-3 Nippon Steel Co., Ltd., Nagoya Steel Works (56) References JP-A-63-75056 (JP, A) Special Kai 64-69685 (JP, A)

Claims (3)

(57) [Claims] 1. To 100 parts by weight of a thermoplastic saturated polyester resin having a glass transition temperature of −30 to 60 ° C. and a loss tangent of 0.5 or more at this glass transition temperature,
A composition for a composite damping material, which comprises 0.05 to 1 part by weight of an acid anhydride and 0.05 to 10 parts by weight of an epoxy compound having two or more epoxy groups in one molecule. 2. The acid anhydride and the epoxy compound compounded in the thermoplastic saturated polyester resin are in a molar ratio of epoxy group / acid anhydride group of 0.5 to 5. The composition for a composite vibration damping material as described. 3. The compound according to claim 1, wherein at least one component of the acid anhydride is a polyfunctional compound having two or more acid anhydride groups in one molecule. The composition for composite type vibration damping material.