JP2017089823A - Process of manufacturing sheet making body and vibration controlled member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process of manufacturing sheet making body enabling a vibration-controlled member showing a superior balance between a well vibration controlled characteristic and a mechanical characteristic to be manufactured and the vibration-controlled member attained by using the sheet making body.SOLUTION: This invention relates to a sheet making body applied for manufacturing a vibration-controlled member. When a cured item composed of the sheet making body with a bending elastic modulus of the sheet making body at 25°C being 5 GPa or more and 50 GPa or less and having width of 10 mm, length of 250 mm and thickness of 2 mm manufactured in accordance with JIS K7391 is applied as a test piece, a vibration attenuation characteristic test is carried out for the test piece by a central vibration applying method and a maximum loss coefficient at a frequency range of 1,000 Hz or more and 20,000 Hz or less measured by a half-value width method is 0.07 or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a papermaking body and a method for manufacturing a vibration damping material.

  Conventionally, motor parts mounted on various devices including automobiles and home appliances and their peripheral parts have vibration suppression characteristics to suppress vibration during use and noise generated by such vibrations. Measures such as pasting a member (damping material) are taken. Examples of the technology related to such a vibration damping material include the following.

  Patent Document 1 discloses a vibration-damping material mainly composed of an olefin resin obtained by dynamically cross-linking ethylene-propylene-diene rubber while melt kneading polypropylene and ethylene-propylene-diene rubber, and a tackifier. Is disclosed.

Papermaking is generally used as a technical term that indicates the state of an object obtained by using a method of spreading fiber materials. This state is described in Patent Documents 2 and 3, for example. According to the document, the papermaking product is described as a wet solid content remaining on a filter after a liquid component is dehydrated from a raw material slurry in which raw materials such as fibers and resins are dispersed in a dispersion medium. ing. The said wet state here means the hardening state before performing drying and heat processing, ie, the hardening state before post-cure.
Moreover, according to the same literature, the said papermaking body is utilized for the molded object obtained by heating and drying-molding in a shaping | molding die. That is, it is described that the papermaking body is used as a molding material.

JP 2002-80660 A Japanese Patent No. 4675276 Patent No. 5426399

  However, although the conventional damping material such as Patent Document 1 can attenuate the vibrations of various devices, there is room for improvement in terms of durability against physical stress applied by such vibrations. It was.

  Therefore, the present invention provides a papermaking body capable of producing a vibration damping material having an excellent balance between good vibration damping characteristics and mechanical characteristics, and a method for manufacturing the vibration damping material obtained using the same.

According to the present invention, a papermaking body used for producing a damping material,
The bending elastic modulus of the papermaking body at 25 ° C. is 5 GPa or more and 50 GPa or less,
When a cured product made of the papermaking body having a width of 10 mm, a length of 250 mm, and a thickness of 2 mm prepared according to JIS K7391 is used as a test piece, a vibration damping characteristic test is performed by a central excitation method using the test piece, There is provided a papermaking product having a maximum loss coefficient of 0.07 or more in a frequency range of 1,000 Hz or more and 20,000 Hz or less measured by a half-width method.

  Furthermore, according to this invention, the manufacturing method of the damping material including the process of shape | molding the said papermaking body is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the papermaking body which can produce the damping material excellent in the balance of a favorable damping characteristic and a mechanical characteristic, and the manufacturing method of the damping material obtained using it can be provided.

It is a perspective schematic diagram which shows an example of the papermaking body which concerns on this embodiment. It is a cross-sectional schematic diagram which shows an example of the manufacturing method of the papermaking body which concerns on this embodiment.

<Paper making>
The papermaking according to the present embodiment is used for producing a vibration damping material, and the bending elastic modulus of the papermaking at 25 ° C. is 5 GPa or more and 50 GPa or less, and a width of 10 mm produced according to JIS K7391. When a cured product made of the papermaking product having a length of 250 mm and a thickness of 2 mm was used as a test piece, a vibration damping characteristic test was performed by a center excitation method using the test piece, and the measured value was 1,000 Hz measured by a half-width method. The maximum loss coefficient in the frequency range of 20,000 Hz or less is 0.07 or more. By doing so, it is possible to realize a vibration damping material having an excellent balance between good vibration damping characteristics and mechanical characteristics.

  Conventional vibration damping materials have room for improvement in terms of durability against physical stress applied by vibrations of various devices. Specifically, although the conventional damping material can attenuate the vibrations of various devices, a physical stress is applied over time due to such vibrations, resulting in a disadvantage that the damping characteristics gradually deteriorate. Had a case.

  On the other hand, in the papermaking product according to the present embodiment, the flexural modulus at 25 ° C. and the maximum loss coefficient in the frequency range from 1,000 Hz to 20,000 Hz show specific numerical values. Therefore, according to the papermaking body according to the present embodiment, even when a physical stress is applied over time due to vibrations of various devices, as in the case of a conventional vibration damping material, the vibrations and the vibrations are accompanied. It is possible to realize a damping material with a good balance between the damping characteristics that are excellent enough to suppress noise generated by the above and the mechanical characteristics that are excellent enough to suppress the above-described deterioration of the damping characteristics. .

  Moreover, the papermaking body which concerns on this embodiment is a molding material for producing the damping material mentioned later. Specifically, the vibration damping material can be produced by forming the papermaking body by a technique such as a heat and pressure press process. Therefore, the papermaking body may be in the form of a sheet, or may be in the form of a body that has been processed into a shape imitating a desired molded product shape.

  The papermaking body according to the present embodiment has a bending elastic modulus of 5 GPa or more and 50 GPa or less at 25 ° C., preferably 7 GPa or more and 50 GPa or less, and more preferably 8 GPa or more and 50 GPa or less. By doing so, since it is possible to improve the mechanical strength of the damping material, it is possible to realize a damping material having excellent long-term reliability during use.

  The papermaking body according to the present embodiment has a vibration damping characteristic by a central excitation method using a test piece when the papermaking body having a width of 10 mm, a length of 250 mm, and a thickness of 2 mm prepared according to JIS K7391 is used as a test piece. The maximum loss coefficient in the frequency range of 1,000 Hz to 20,000 Hz measured by the half-width method is 0.07 or more, preferably 0.1 or more, more preferably It is 0.14 or more. By doing so, it is possible to obtain a vibration damping material with further improved vibration damping characteristics, so the physical stress applied by the vibration of various devices can be reduced, resulting in long-term reliability during use. It is possible to realize a vibration damping material with excellent properties. It is sufficient that the maximum value of the maximum loss coefficient is about 0.3.

  Further, the papermaking body according to the present embodiment has a bending strength of the papermaking body at 25 ° C. of preferably 50 MPa or more and 500 MPa or less, more preferably 100 MPa or more and 500 MPa or less, and most preferably 150 MPa or more and 500 MPa or less. It is as follows. By doing so, it is possible to realize a vibration damping material that is even better in terms of the balance between rigidity and vibration damping performance.

  Here, the papermaking body which concerns on this embodiment is formed by the papermaking method as the name shows. As will be described later, the papermaking method indicates a papermaking technique which is one of papermaking techniques. Therefore, the papermaking body contains a fiber material.

  Moreover, it is preferable that the papermaking body which concerns on this embodiment contains the binder which can bind the fiber material mentioned above.

FIG. 1 is a schematic perspective view showing an example of a papermaking body 10 according to the present embodiment.
In FIG. 1, the enlarged schematic diagram of the area | region shown with a dotted line of a papermaking body is shown. The papermaking body 10 according to the present embodiment includes a binder resin A and a fiber material B. Moreover, it is preferable that the fiber material B is arranged in the plane direction as shown in FIG. 1 from the viewpoint of improving the vibration damping characteristics of the papermaking body 10. In other words, the papermaking body 10 according to this embodiment has a random orientation of the fiber material B when viewed from the plane direction, while the fiber material B is arranged in the plane direction when viewed from the thickness direction. Is preferred.
Further, the binder resin A contained in the papermaking body 10 functions as a binder for binding the fiber materials B together, and also functions as a molding material for making the papermaking body into a molded body by a subsequent heat treatment. The binder resin A in the papermaking body 10 is not completely cured, for example, in a B stage state. By heating the papermaking body 10 at the curing temperature of the binder resin A to be used, the papermaking body 10 can be deformed into another shape, and the binder resin A can be completely cured to obtain a molded body. The papermaking body 10 is used as a molding material for producing a molded body.

The papermaking body 10 according to the present embodiment is obtained by a papermaking method described later, and has structural features A to C in the following points.
(Feature A) The fiber material is randomly oriented in a plan view of the surface of the papermaking body 10.
(Feature B) In the cross-sectional view in the thickness direction of the papermaking body 10, the orientation state of the fiber material is highly controlled, and the fiber material is oriented in a specific direction. In other words, the fiber material is in a laminated state in the thickness direction of the papermaking body 10.
(Feature C) The fiber materials are bound together with a binder resin.

  Since the papermaking body according to the present embodiment is formed by a papermaking method, the fiber material B can be uniformly dispersed in the papermaking body 10, and the entanglement between the fiber materials B can be appropriately made. It is estimated that. Although not necessarily clear, it is considered that for these reasons, it is possible to improve the balance between damping characteristics and mechanical characteristics of the damping material formed using the papermaking body 10. Moreover, since the papermaking method is excellent in workability, the designability of the papermaking body 10 can also be improved. In the papermaking method, there are few restrictions on the combination of materials constituting the papermaking body 10. For this reason, according to the characteristic calculated | required by the damping material, other various additives can be suitably used with the binder resin A and the fiber material B.

The papermaking body 10 can have a flat plate shape, for example.
As described above, the fiber material B is arranged in the plane direction in the papermaking body 10. Thereby, especially the damping characteristic of the papermaking body 10 in a plane direction (thickness direction) can be improved. In the enlarged cross-sectional view of the papermaking body 10 shown in FIG. 1, the fiber materials B (B in FIG. 1) are arranged in the plane direction, and the binder resin A (A in FIG. 1) is interposed between the fiber materials B. The case where it intervenes is illustrated. In this case, the fiber materials B are bound to each other by, for example, the binder resin A.

  In the enlarged plan view of the papermaking body 10 shown in FIG. 1, the case where the fiber materials B are randomly arranged in the plane and entangled with each other is illustrated. The fiber material B may have a linear shape in a plan view, may be curved, or may be bent. Also in the plan view, for example, the binder resin A is interposed between the fiber materials B.

  Hereinafter, the material which forms the papermaking body 10 is demonstrated in detail.

(Binder resin A)
As the name suggests, the binder resin A acts as a binder for binding the fiber material B in the papermaking body 10. Therefore, the binder resin A only needs to be capable of binding the fiber material B. As this binder resin A, a thermosetting resin is mentioned. As such a thermosetting resin, for example, it is preferable to use a resin that is in a solid form at room temperature (25 ° C.) in a non-heated state from the viewpoint of stably producing the papermaking body 10.

  Specific examples of the thermosetting resin include phenol resin, epoxy resin, unsaturated polyester resin, melamine resin, and polyurethane. These may be used individually by 1 type and may use 2 or more types together. Among these, the inclusion of at least one of a phenol resin and an epoxy resin is more preferable from the viewpoint of improving the balance between the vibration damping characteristics and the mechanical characteristics of the papermaking body 10.

  In the present embodiment, the papermaking body 10 can include, for example, a thermosetting resin having a granular or powdery shape. Thereby, the mechanical property of the hardened | cured material obtained by hardening the papermaking body 10 can be improved more effectively. The reason for this is not clear, but when the papermaking body 10 is molded by heating and pressing, the thermosetting resin has a granular or powdery shape, so that the impregnation property at the time of melting is improved. It is estimated that the interface between the filler C and the thermosetting resin is well formed. In the present embodiment, for example, a thermosetting resin that is a granular material, a fiber material B, and a filler C are made to produce the papermaking body 10 to produce a thermosetting having a granular or powdery shape. It is possible to realize the papermaking body 10 containing the conductive resin.

  Examples of the thermosetting resin having a granular or powdery shape may include those having an average particle diameter of 500 μm or less. From the viewpoint of more effectively improving the mechanical properties of the cured product obtained by curing the papermaking body 10, the average particle size of the thermosetting resin having a granular or powdery shape is 1 nm or more and 300 μm or less. Is more preferable. The thermosetting resin having such an average particle diameter can be obtained by performing a pulverization process using, for example, an atomizer pulverizer. The average particle size of the thermosetting resin is determined by using a laser diffraction particle size distribution measuring device such as SALD-7000 manufactured by Shimadzu Corporation as the average particle size based on a 50% particle size. Can do.

  The content of the thermosetting resin is preferably 5% by weight or more, more preferably 15% by weight or more, and most preferably 20% by weight or more based on the total amount of the papermaking product 10. Thereby, the workability and lightness of the papermaking body 10 can be improved more effectively. On the other hand, the content of the thermosetting resin is preferably 80% by weight or less, more preferably 60% by weight or less, and most preferably 40% by weight or less based on the total amount of the papermaking product 10. . Thereby, it becomes possible to improve more effectively the thermal characteristic of the hardened | cured material obtained by hardening the papermaking body 10. FIG.

(Fiber material B)
The papermaking body 10 according to the present embodiment preferably includes liquid crystal polymer fibers as the fiber material B. Here, the liquid crystal polymer fiber refers to a fiber obtained by melt spinning a liquid crystal polymer. The liquid crystal polymer refers to a thermoplastic resin exhibiting liquid crystal-like properties in which a linear chain of molecules is regularly arranged in a molten state. Moreover, since the liquid crystal polymer fiber is obtained by making the liquid crystal polymer into a fiber, the alignment direction of the liquid crystal is oriented in a specific direction. Therefore, it is generally said that the molecular orientation characteristics of the liquid crystal polymer fiber are exceptionally high compared to other fiber materials.
In addition, since the liquid crystal polymer fiber exhibits the above-described unique molecular orientation characteristics, it not only exhibits excellent mechanical strength and rigidity, but the thickness of the molded product obtained by blending the liquid crystal polymer fiber becomes thinner. It is a fiber material having the feature of increasing its mechanical strength. Furthermore, the liquid crystal polymer fiber is a fiber material having a low linear expansion coefficient close to that of a metal and also having excellent vibration absorption characteristics despite having a high elastic modulus. Therefore, when the liquid crystal polymer fiber is used as the fiber material B, it is possible to impart various characteristics expressed by the liquid crystal polymer fiber itself to the obtained molded product. It is possible to realize a vibration damping material that is even better in terms of balance of mechanical properties. Specifically, when the liquid crystal polymer fiber is used as the fiber material B, the various properties obtained because the papermaking body 10 obtained by the papermaking method is used as a molding material, and the liquid crystal polymer fiber are used. Therefore, it is possible to realize a vibration damping material that is even more excellent in terms of the balance between vibration damping characteristics and mechanical characteristics due to a synergistic effect with various characteristics obtained.

  Examples of the liquid crystal polymer contained in the above-described liquid crystal polymer fiber include aromatic polyesters that are synthesized from monomers such as aromatic diols, aromatic carboxylic acids, and hydroxycarboxylic acids and that exhibit liquid crystallinity when melted. Representative examples thereof include a first type liquid crystal polymer composed of parahydroxybenzoic acid and ethylene terephthalate, a second type liquid crystal polymer composed of p-hydroxybenzoic acid and 4,4′-dihydroxybiphenylphthalic acid, Examples thereof include a third type of liquid crystal polymer composed of p-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid. Among them, the liquid crystal polymer fiber according to the present embodiment is a second type liquid crystal polymer composed of p-hydroxybenzoic acid and 4,4′-dihydroxybiphenylphthalic acid, or p-hydroxybenzoic acid and 2-hydroxy-6. -It is preferable to contain the 3rd type liquid crystal polymer which consists of naphthoic acid.

  The content of the liquid crystal polymer fiber is preferably 45% by weight or more, more preferably 50% by weight or more, and most preferably 55% by weight or more based on the total amount of the papermaking product 10. Thereby, the balance of the damping characteristics and mechanical characteristics of the damping material obtained by molding the papermaking body 10 can be further improved.

  In addition, the papermaking body 10 according to the present embodiment has various characteristics such as mechanical properties of the vibration damping material obtained by molding the papermaking body 10, together with the liquid crystal polymer fiber described above, You may use together filler C, such as the fibrous filler C1 mentioned later and the filler C2 whose aspect ratio is smaller than the said fibrous filler C1.

(Filler C)
First, the fibrous filler C1 will be described.

  The fiber filler C1 includes, for example, metal fibers; inorganic fibers such as carbon fibers, glass fibers, and ceramic fibers; natural fibers such as wood fibers, cotton, hemp, and wool; regenerated fibers such as rayon fibers; semisynthetic fibers such as cellulose fibers; One kind selected from synthetic fibers such as polyamide fiber, aramid fiber, polyimide fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, polyparaphenylene benzoxazole fiber, polyethylene fiber, polypropylene fiber, polyacrylonitrile fiber, ethylene vinyl alcohol fiber, or the like Two or more types can be included. Among these, from the viewpoint of improving the thermal conductivity of the molded article, it is preferable to include one or more of metal fibers and inorganic fibers, and to include at least one of metal fibers and carbon fibers. More preferred. Further, from the viewpoint of improving the mechanical properties of the molded article, it is more preferable to include one or more of synthetic fibers and inorganic fibers. In particular, from the viewpoint of improving the bending strength of the molded product, it is particularly preferable to include carbon fibers. Moreover, it is especially preferable that an aramid fiber is included from a viewpoint of improving the impact resistance of a molded article. From the viewpoint of improving the electromagnetic wave shielding performance of the molded product, it is more preferable to include a metal fiber.

  The metal fiber may be a metal fiber composed of a single metal element or an alloy fiber composed of a plurality of metals. The metal fiber preferably contains one or more metal elements selected from the group consisting of aluminum, silver, copper, magnesium, iron, chromium, nickel, titanium, zinc, tin, molybdenum and tungsten, for example. In addition, as a metal fiber in this embodiment, for example, Nippon Seisen Co., Ltd. and Bekaert Japan Co., Ltd. stainless fiber, Niji Co., Ltd. copper fiber, aluminum fiber, brass fiber, steel fiber, titanium fiber, Phosphor bronze fibers and the like are available as commercial products, but are not limited to these. These metal fibers may be used individually by 1 type, or may use 2 or more types together. Of these, one or more of copper fiber, aluminum fiber, and brass fiber is preferable from the viewpoint of thermal conductivity, and one or more of stainless fiber, copper fiber, and aluminum fiber are preferable from the viewpoint of electromagnetic shielding properties. preferable.

  As the fibrous filler C1, a surface treating agent such as a silane coupling agent, an aluminate coupling agent, a titanate coupling agent or the like according to necessary characteristics, or a converging agent for improving adhesion and handling properties with a resin. You may use what was processed.

  The aspect ratio of the fibrous filler C1 is preferably 100 or more, more preferably 150 or more, and most preferably 200 or more. Thereby, the damping characteristic of the damping material obtained by shape | molding the papermaking body 10 can be improved. On the other hand, the aspect ratio of the fibrous filler C1 is preferably 1000 or less from the viewpoint of improving the ease of manufacturing the papermaking body 10 and improving the strength of the damping material obtained by molding the papermaking body 10. Preferably, it is 700 or less. The aspect ratio of the fibrous filler C1 is determined by the fiber length / fiber width. Moreover, the fibrous filler C1 in this specification is the concept which does not contain the pulp D mentioned later.

  The fiber length of the fibrous filler C1 is preferably, for example, 100 μm or more and 200 mm or less, more preferably 500 μm or more and 50 mm or less, and particularly preferably 500 μm or more and 10 mm or less. Further, the fiber width of the fibrous filler C1 is, for example, preferably 0.5 μm or more and 1 mm or less, and more preferably 3 μm or more and 100 μm or less. By setting the fiber length and fiber width of the fibrous filler C1 within the above ranges, it becomes easier to set the aspect ratio of the fibrous filler C1 within a desired range. For this reason, the intensity | strength of the damping material obtained by shape | molding the papermaking body 10 can be improved more effectively. Moreover, it becomes possible to contribute to the improvement of the uniform dispersibility of the fiber material B in the papermaking body 10.

  The fibrous filler C1 can have various shapes according to necessary characteristics. In the present embodiment, for example, chopped fiber can be used as the fibrous filler C1. This makes it possible to more stably realize a vibration damping material that is even better in terms of the balance between vibration damping characteristics and mechanical characteristics.

  The content of the fibrous filler C1 is preferably 15% by weight or more, more preferably 30% by weight or more, and particularly preferably 45% by weight or more based on the entire papermaking body 10. Thereby, about the molded object obtained by shape | molding the papermaking body 10, the balance of a mechanical characteristic, a thermal characteristic, and electromagnetic wave shielding can be improved more effectively. On the other hand, the content of the fibrous filler C1 is preferably 80% by weight or less, more preferably 70% by weight or less, and particularly preferably 65% by weight or less based on the entire papermaking body 10. . Thereby, the workability and lightness of the papermaking body 10 can be improved. It is also possible to improve the dispersibility of the fibrous filler C1 more effectively and contribute to the improvement of the mechanical properties, thermal properties, and electromagnetic wave shielding properties of the molded product obtained by molding the papermaking product 10. is there.

  Next, the filler C2 whose aspect ratio is smaller than the fibrous filler C1 will be described.

  As described above, the filler C2 has an aspect ratio smaller than that of the fibrous filler C1. In addition, when the filler C2 is fibrous, the aspect ratio of the filler C2 can be calculated | required by fiber length / fiber width. On the other hand, when the filler C2 is a granular material, it can be determined from the ratio of the longest diameter, the longest diameter, to the shortest diameter, the longest diameter / shortest diameter. Moreover, the filler C2 in this specification is the concept which does not contain the pulp D mentioned later.

  The aspect ratio of the filler C2 is preferably 50 or less, more preferably 30 or less, and most preferably 20 or less. Thereby, the damping characteristic of the damping material obtained by shape | molding the papermaking body 10 can be improved. On the other hand, the lower limit of the aspect ratio of the filler C2 can be set to 1, for example. From the viewpoint of improving the balance between the mechanical strength and the vibration damping characteristics of the molded body obtained by molding the papermaking product 10 by entanglement with the fibrous filler C2, the aspect ratio of the filler C2 is more preferably 3 or more. preferable.

  The fiber length or major axis of the filler C2 is preferably 1 μm or more and 10 mm or less, more preferably 10 μm or more and 1 mm or less, and most preferably 10 μm or more and 500 μm or less. Further, the fiber width or minor axis of the filler C2 is preferably 0.5 μm or more and 500 μm or less, and more preferably 1 μm or more and 100 μm or less. Thereby, it becomes easier to set the aspect ratio of the filler C2 within a desired range. The strength of the damping material obtained by molding the papermaking body 10 can be improved more effectively. In addition, the balance between mechanical strength and damping characteristics can be improved. Furthermore, it becomes possible to contribute to the improvement of the uniform dispersibility of the filler C2 in the papermaking body 10. In the present embodiment, for example, a filler having a fiber length shorter than the fibrous filler C1 can be used as the filler C2.

  The filler C2 can have various shapes depending on required characteristics. In this embodiment, as filler C2, at least one of fiber materials, such as a milled fiber, or a granular material, for example can be used. Thereby, about the damping material using the papermaking body 10, it becomes possible to implement | achieve the outstanding thermal conductivity more stably. Moreover, it can also contribute to the improvement of the uniform dispersibility of the filler C2 in the papermaking body 10. From the viewpoint of improving the thermal conductivity, for example, it is more preferable to include one or both of milled fiber or powder as filler C2, and it is particularly preferable to include at least powder.

  When the filler C2 includes a fiber material, the filler C2 is, for example, one or more selected from the group consisting of aluminum, silver, copper, magnesium, iron, chromium, nickel, titanium, zinc, tin, molybdenum, and tungsten. Metal fibers containing various metal elements; inorganic fibers such as carbon fibers, glass fibers, and ceramic fibers; natural fibers such as wood fibers, cotton, hemp, and wool; regenerated fibers such as rayon fibers; semi-synthetic fibers such as cellulose fibers; polyamides One or two selected from synthetic fibers such as fiber, aramid fiber, polyimide fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, polyparaphenylene benzoxazole fiber, polyethylene fiber, polypropylene fiber, polyacrylonitrile fiber, and ethylene vinyl alcohol fiber More than seeds Mukoto can. Among these, from the viewpoint of improving thermal conductivity, it is preferable to include one or more of metal fibers and inorganic fibers, and it is more preferable to include at least one of metal fibers and carbon fibers. From the viewpoint of improving the balance between mechanical properties and thermal conductivity, it is particularly preferable to include at least carbon fiber.

  When the filler C2 includes a granular material, the filler C2 is made of, for example, carbon material such as graphite, carbon black, charcoal, coke, diamond, carbon nanotube, graphene, fullerene, talc, fired clay, unfired clay, mica, and glass. Silicates such as silicates, oxides such as titanium oxide, alumina, silicon compounds such as magnesium silicate, fused silica, crystalline silica, carbonates such as calcium carbonate, magnesium carbonate, hydrotalcite, zinc oxide, oxidation Oxides such as magnesium, hydroxides such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, sulfates or sulfites such as barium sulfate, calcium sulfate, calcium sulfite, zinc borate, barium metaborate, Aluminum borate, calcium borate, boro It can include borate, such as sodium, aluminum nitride, boron nitride, one or more kinds of granular material selected from nitrides such as silicon nitride. Among these, from the viewpoint of improving the balance between mechanical characteristics and vibration damping characteristics, it is preferable to include a carbon material, and it is more preferable to include at least one of graphite or carbon black.

  Filler C2 has a surface treatment with a silane coupling agent, an aluminate coupling agent, a titanate coupling agent, etc., depending on the required properties, and a sizing agent treatment to improve adhesion and handling with the resin. You may use what you did.

(Pulp D)
The papermaking body 10 can contain pulp D, for example. Pulp D is a fiber material having a fibril structure, and can be obtained, for example, by mechanically or chemically fibrillating the fiber material. In the manufacturing method of the papermaking body 10 using the papermaking method described later, the thermosetting resin can be more effectively aggregated by making pulp D together with the thermosetting resin, the fiber material B, and the filler C. Therefore, it becomes possible to realize a more stable production of the papermaking body 10.

  Examples of the pulp D include cellulose fibers such as linter pulp and wood pulp, natural fibers such as kenaf, jute and bamboo, para-type wholly aromatic polyamide fibers (aramid fibers) and copolymers thereof, aromatic polyester fibers, and polybenza. Examples include fibrillated organic fibers such as sol fibers, meta-type aramid fibers and copolymers thereof, acrylic fibers, acrylonitrile fibers, polyimide fibers, and polyamide fibers. The pulp D can contain 1 type, or 2 or more types of these. Among these, from the viewpoint of improving the mechanical characteristics and damping characteristics of the damping material using the papermaking body 10, and from the viewpoint of improving the dispersibility of the fiber material B, an aramid pulp composed of aramid fibers, and It is particularly preferable that one or both of polyacrylonitrile pulp constituted by acrylonitrile fiber is included.

  The content of the pulp D is preferably 0.5% by weight or more, more preferably 1.5% by weight or more, and particularly preferably 2% by weight or more with respect to the total amount of the papermaking product 10. Thereby, aggregation of the thermosetting resin at the time of papermaking can be generated more effectively, and further stable production of the papermaking body 10 can be realized. Further, the content of the pulp D is preferably 15% by weight or less, more preferably 10% by weight or less, and particularly preferably 8% by weight or less with respect to the total amount of the papermaking product 10. Thereby, it becomes possible to improve the mechanical characteristics and thermal characteristics of the cured product obtained by curing the papermaking body 10 more effectively.

(Flocculant E)
The papermaking body 10 can contain the flocculant E, for example. The aggregating agent E has a function of aggregating the thermosetting resin and the fiber material in a flock shape in the method for manufacturing the papermaking body 10 using the papermaking method described later. For this reason, more stable production of the resin sheet can be realized.

  The flocculant E can include, for example, one or more selected from a cationic polymer flocculant, an anionic polymer flocculant, a nonionic polymer flocculant, and an amphoteric polymer flocculant. Examples of such a flocculant E include cationic polyacrylamide, anionic polyacrylamide, Hoffman polyacrylamide, mannic polyacrylamide, amphoteric copolymer polyacrylamide, cationized starch, amphoteric starch, polyethylene oxide and the like. it can. In the flocculant E, the polymer structure and molecular weight, the amount of functional groups such as hydroxyl groups and ionic groups, and the like can be adjusted without particular limitation according to the required characteristics.

  The content of the flocculant E is preferably 0.05% by weight or more, more preferably 0.1% by weight or more, based on the total amount of the constituent materials of the papermaking product 10 described above, It is particularly preferable that the amount be at least% by weight. Thereby, in the manufacture of the papermaking body 10 using the papermaking method, the yield can be improved. On the other hand, the content of the flocculant E is preferably 3% by weight or less, more preferably 2% by weight or less, and more preferably 1.5% by weight with respect to the total amount of the constituent materials of the papermaking product 10 described above. % Or less is particularly preferable. Thereby, in manufacture of the papermaking body 10 using a papermaking method, it becomes possible to perform a dehydration process etc. more easily and stably.

  The papermaking body 10 can contain, for example, a powdery substance having ion exchange ability in addition to the above-described components. As the powdery substance having ion exchange ability, it is preferable to use one or more intercalation compounds selected from, for example, clay minerals, scaly silica fine particles, hydrotalcites, fluorine teniolite and swellable synthetic mica. Examples of the clay mineral include smectite, halloysite, kanemite, kenyanite, zirconium phosphate, and titanium phosphate. Examples of hydrotalcites include hydrotalcite and hydrotalcite-like substances. Examples of the fluorine teniolite include lithium-type fluorine teniolite and sodium-type fluorine teniolite. Examples of the swellable synthetic mica include sodium-type tetrasilicon fluorine mica and lithium-type tetrasilicon fluorine mica. These intercalation compounds may be natural products or synthesized ones. Among these, clay minerals are more preferable, and smectite is more preferable in that it exists from natural products to synthetic products and has a wide range of selection. Examples of the smectite include montmorillonite, beidellite, nontronite, saponite, hectorite, soconite, and stevensite, and any one or more of these can be used. Montmorillonite is a hydrated silicate of aluminum, but may be bentonite containing montmorillonite as a main component and minerals such as quartz, mica, feldspar, and zeolite. Synthetic smectite with few impurities is preferable when used for applications such as coloring and impurities.

  In addition, the papermaking product 10 includes, for example, stabilizers such as antioxidants and ultraviolet absorbers for the purpose of improving characteristics, mold release agents, plasticizers, flame retardants, resin curing catalysts and curing accelerators, pigments, and dry paper strength. Paper strength improvers such as improvers, wet paper strength improvers, yield improvers, freeness improvers, size fixers, antifoaming agents, rosin sizing agents for acidic papermaking, rosin sizing agents for neutral papermaking, alkyl One or two selected from additives such as ketene dimer sizing agents, alkenyl succinic anhydride sizing agents, sizing agents such as specially modified rosin sizing agents, and coagulants such as sulfate bands, aluminum chloride, and polyaluminum chloride. More than seeds can be included for the purpose of adjusting production conditions and expressing required physical properties.

Next, the manufacturing method of the papermaking body 10 is demonstrated.
FIG. 2 is a schematic cross-sectional view illustrating an example of a method for manufacturing the papermaking body 10 according to the present embodiment.
The papermaking body 10 is manufactured using, for example, a wet papermaking method. The manufacturing method of the papermaking body 10 which concerns on this embodiment includes the process of papermaking the material composition containing binder resin A and the fiber material B, for example. In addition, the said material composition may contain the filler C. Therefore, in the following description, a case where a material composition containing filler C is made together with a thermosetting resin and liquid crystal polymer fibers will be described as an example.

  First, as shown to Fig.2 (a), the component except the flocculant E among the above-mentioned each component is added to a solvent, and it stirs and disperses. Here, the thermosetting resin, the liquid crystal polymer fiber, the filler C, and other additives as necessary are added to the solvent, and are stirred and dispersed. Thereby, the varnish-like material composition for forming the papermaking body 10 can be obtained. A method for dispersing each component in a solvent is not particularly limited, and examples thereof include a method of stirring using a disperser. In FIG. 2, symbol A indicates a thermosetting resin, and symbol B indicates a liquid crystal polymer fiber.

  Although it does not specifically limit as a solvent, It is hard to volatilize in the process which disperse | distributes the constituent material of the said material composition, It is easy to desolvate in order to suppress the residual in the papermaking body 10, Energy is removed by desolvation. From the viewpoint of suppressing the increase, it is preferable that the boiling point is 50 ° C. or higher and 200 ° C. or lower. Examples of such a solvent include water, alcohols such as ethanol, 1-propanol, 1-butanol, and ethylene glycol; ketones such as acetone, methyl ethyl ketone, 2-heptanone, and cyclohexanone; ethyl acetate, butyl acetate, Examples thereof include esters such as methyl acetoacetate and ethers such as tetrahydrofuran, isopropyl ether, dioxane and furfural. These solvents may be used alone or in combination of two or more. Among these, it is particularly preferable to use water because of its abundant supply amount, low cost, low environmental load, high safety and easy handling.

  In the above step of obtaining a varnish-like material composition, as the thermosetting resin, for example, a solid-state resin having an average particle size of 500 μm or less can be used. Thereby, in the process of aggregating the thermosetting resin described later, the agglomerated state can be more easily formed. In the above step of obtaining a varnish-like material composition, the average particle size of the thermosetting resin is more preferably 1 nm or more and 300 μm or less. The thermosetting resin having such an average particle diameter can be obtained by performing a pulverization process using, for example, an atomizer pulverizer. The average particle size of the thermosetting resin is determined by using a laser diffraction particle size distribution measuring device such as SALD-7000 manufactured by Shimadzu Corporation as the average particle size based on a 50% particle size. Can do.

  In this embodiment, the flocculant E can be added to the varnish-like material composition obtained above. Thereby, it becomes easier to obtain the aggregate F by aggregating the thermosetting resin, the liquid crystal polymer fiber, and the filler C in the solvent in a floc form.

  Next, as shown in FIG. 2 (b), the solvent and the agglomerate F obtained above are put into a container having a bottom surface made of the mesh 30, and the solvent is discharged from the mesh 30. Thereby, the aggregate F and the solvent can be separated from each other. At this time, the aggregate F remains in a sheet form on the mesh 30. In the present embodiment, it is possible to adjust the shape of the resulting papermaking body 10 by appropriately selecting the shape of the mesh 30.

  In the present embodiment, the sheet-like aggregate F obtained above can be taken out, placed in a drying furnace and dried, and the solvent can be further removed. For example, in this way, the papermaking body 10 as shown in FIG. 2 (c) is manufactured.

(Damping material)
The damping material according to the present embodiment is obtained by molding the papermaking body 10 described above. Here, as a method of molding the vibration damping material according to the present embodiment, for example, press molding or the like can be cited. Specifically, first, the papermaking body 10 is pressed with a press plate, and a hot plate is disposed on the outer peripheral side of the press plate and heated. Thereby, the molded object which comprises a damping material can be obtained. In addition, when a thermosetting resin is contained as the binder resin A in the papermaking body 10, for example, the above molding process can be performed so that the thermosetting resin in the molded body is in a semi-cured state. Thereby, since a molded object can be thermoset after laminating a molded object to another member, it becomes possible to make a molded object and another member adhere to each other more strongly.

  It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

  Next, examples of the present invention will be described.

<Examples and Comparative Examples>
(Production of papermaking)
First, binder resin (A), fiber material (B), filler (C), and pulp (D) pulverized to an average particle size of 100 μm (50% particle size based on mass) with an atomizer pulverizer will be described later. According to the formulation, it was added to water as a solvent and stirred for 30 minutes with a disperser to obtain a mixture. Here, a total of 100 parts by weight of the binder resin (A), the fiber material (B), the filler (C), and the pulp (D) was added to 10,000 parts by weight of water. Subsequently, the constituent materials (binder resin (A), fiber material (B), filler (C), pulp (D)) described above were aggregated in a flock shape. The resulting agglomerates are separated from water by a 30 mesh metal net, and then the agglomerates are dehydrated and pressed, and further placed in a dryer at 50 ° C. for 5 hours to be dried to form a composite resin composition. A papermaking body in an uncured state was obtained. The yield was 97%. Moreover, the obtained papermaking body was a sheet form and the thickness was 300 micrometers.

  About the papermaking body of an Example and a comparative example, all confirmed that the fiber material (B) was arranged in the plane direction in the resin sheet. Details of each component shown in Table 1 are as follows. In addition, the unit of the mixture ratio of each component in Table 1 is% by weight.

(A) Binder resin Phenolic resin: Resole resin (PR-51723, manufactured by Sumitomo Bakelite Co., Ltd.)
Polypropylene resin: manufactured by Tokyo Ink

(B) Fiber material B
Liquid crystal polymer fiber: 3mm cut fiber (Kuraray, Vectran)

(C) Filler carbon fiber: XN-100 (manufactured by Nippon Graphite Fiber Co., Ltd., fiber length 3 mm, fiber width 10 μm, aspect ratio 300)
Aramid fiber: Technora T-32PNW (manufactured by Teijin Limited, fiber length 3 mm)

(D) Pulp aramid pulp: Kevlar pulp 1F303 (manufactured by Toray DuPont)

(Production of damping material)
A damping material was manufactured as follows. First, each of the paper products obtained above was cut into 10 cm × 30 cm, and heat treated for 10 minutes under the conditions of a pressure of 300 kg / cm ² and a temperature of 180 ° C., thereby a damping material of 10 cm × 30 cm × 2 mm. Got.

(Maximum loss factor)
A cured product obtained by processing and molding the papermaking bodies of Examples and Comparative Examples so as to have a width of 10 mm, a length of 250 mm, and a thickness of 2 mm according to JIS K7391 was produced as a test piece. Using this test piece, a vibration damping characteristic test was performed by the central excitation method, and the maximum loss coefficient in a frequency range of 1,000 Hz to 20,000 Hz measured by the half-width method was obtained. The table below also shows the frequency value indicating the maximum loss coefficient.

(Bending elastic modulus and bending strength)
About the damping material of an Example and a comparative example, the bending elastic modulus and bending strength in 25 degreeC were measured according to JISK6911. The unit is GPA for bending elastic modulus and MPa for bending strength.

  As shown in Table 1, it can be seen that the damping material according to each example is superior in balance between good damping characteristics and mechanical properties as compared with the damping material according to each comparative example.

10 Papermaking 30 Mesh A Binder resin B Fiber material C Filler F Aggregate

Claims (8)

A papermaking body used for producing a damping material,
The bending elastic modulus of the papermaking body at 25 ° C. is 5 GPa or more and 50 GPa or less,
When a cured product made of the papermaking body having a width of 10 mm, a length of 250 mm, and a thickness of 2 mm prepared according to JIS K7391 is used as a test piece, a vibration damping characteristic test is performed by a central excitation method using the test piece, A papermaking body having a maximum loss factor of 0.07 or more in a frequency range of 1,000 Hz or more and 20,000 Hz or less measured by a half-width method.   The papermaking body of Claim 1 whose bending strength of the said papermaking body in 25 degreeC is 50 Mpa or more and 500 Mpa or less.   The papermaking body of Claim 1 or 2 in which the said papermaking body contains a thermosetting resin and a liquid crystal polymer fiber.   The papermaking body according to claim 3, wherein the thermosetting resin includes one or more selected from the group consisting of a phenol resin, an epoxy resin, an unsaturated polyester resin, a melamine resin, and polyurethane.   The papermaking product according to claim 3 or 4, wherein the content of the thermosetting resin with respect to the total amount of the papermaking product is 5 wt% or more and 80 wt% or less.   The liquid crystal polymer fiber includes a liquid crystal polymer composed of p-hydroxybenzoic acid and 4,4′-dihydroxybiphenylphthalic acid, or a liquid crystal polymer composed of p-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid. The papermaking body as described in any one of Claims 3 thru | or 5.   The papermaking product according to any one of claims 3 to 6, wherein a content of the liquid crystal polymer fiber with respect to the total amount of the papermaking product is 45% by weight or more and 80% by weight or less.   A method for manufacturing a vibration damping material, comprising a step of forming the papermaking product according to any one of claims 1 to 7.

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