JP2003191267A - Molding cushioning material and method for manufacturing laminated sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding cushioning material which is used at the time of molding of a laminated sheet, has a enhanced durability against repeated use for extended life, and reduces the load to environment and production cost as a result. <P>SOLUTION: The molding cushioning material 1 comprises a core layer 2 comprising a material having rubber elasticity and the fiber layers 3 formed on both surfaces of the core layer 2. An intermediate layer 4 wherein the core layer 2 and each of the fiber layers 3 penetrate mutually is formed to the joining part of the core layer 2 and each of the fiber layers 3. The thickness of the intermediate layer 4 is set to a range of 10-70 μm. When this molding cushioning material 1 is used at the time of production of the laminated sheet, the laminated sheet is molded under uniform surface pressure. The molding cushioning material has high durability and is used repeatedly. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding cushion material used for molding a laminated board and a method for manufacturing a laminated board using the molding cushion material.

[0002]

2. Description of the Related Art Conventionally, a laminated board used for producing a printed wiring board or the like used in electronic equipment and electric equipment is obtained by arranging a metal foil such as copper foil on the outside of a required number of prepregs. A plurality of sets of laminated materials are laminated via a molding plate to form an object to be pressured, and the object to be pressured is heated and pressed by a hot platen from above and below to be molded. At the time of this molding, a flexible cushioning material for molding is used in order to prevent scratches on the molding plate and the hot platen and to transmit uniform pressure.

That is, in the above heat and pressure molding process, the prepreg is heated to a molten state and then gradually hardened and solidified. At this time, the prepreg is laminated on the entire surface of the prepreg from a hot platen. In order to evenly transfer the heat and pressure of the above, a cushioning material for molding is interposed between the laminate including the prepreg and the press heating platen.
If you want to mold without using the cushioning material for molding,
While heat is rapidly transferred to the hot plate side of the laminate, heat transfer is slow at the center of the laminate, resulting in a large difference in formability and defective molding. Further, when the hot plate is distorted, the pressure applied to the laminate becomes non-uniform, which causes a problem that unevenness occurs in the molded product.

As a conventionally proposed cushioning material for cushioning, a plurality of cushioning papers such as kraft papers may be piled up according to the molding conditions. The pulp was damaged due to the pressure and became brittle, and it could only be used once under severe molding conditions. For this reason, it is necessary to replace the kraft paper every time, and it is necessary to count and prepare the required number of sheets one by one according to the pressing conditions, which is troublesome. Also, since the cushioning material for molding is frequently exchanged, it is necessary to store a large amount of kraft paper, and it is necessary to control the air conditioning to prevent it from being affected by humidity during this storage. there were. In addition, paper dust may be scattered from the cut surface of the kraft paper, which may adversely affect the product.

For this reason, instead of the kraft paper, a molding material obtained by laminating a cushioning material mainly made of rubber or a web mainly made of heat-resistant fiber and entangled and integrated by needle punching. Although a cushioning material has been developed, it has improved durability in repeated use compared to kraft paper, but its durability is still insufficient. In particular, in a molding cushion material mainly made of rubber, since there are no voids in the rubber, the side surface part which is opened when subjected to a compressive force during molding tends to swell and extend or permanent set, Due to this, the durability was not sufficiently obtained. Further, since the molding cushion material made of a web contains surface irregularities and unit weight unevenness, such surface irregularities and unit weight unevenness may cause variations in heat conduction and pressure irregularities during molding.

In order to improve these problems, a rubber layer made of heat-resistant butyl rubber, nitrile rubber, silicone rubber, fluororubber, etc., and needle punched polyamide fiber, aromatic aramid fiber, aromatic polyester fiber, etc. are used. There has been proposed a cushioning material for molding which is laminated by combining with a non-woven fabric layer and is integrated by vulcanization of rubber (see Japanese Patent Application Laid-Open No. 7-125142). A structure in which a reinforcing layer such as glass cloth is embedded in the rubber layer is also disclosed.

However, in order to meet the recent increasing environmental awareness (reduction of environmental load) and the demand for further cost reduction, the cushioning material for molding is provided with further durability so as to withstand more repeated use. Is required to do.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is used in forming a laminated plate, and has improved durability against repeated use and a long service life. It is an object of the present invention to provide a molding cushion material and a method for manufacturing a laminated plate using the molding cushion material, which can reduce the load on the molding material and reduce the production cost.

[0009]

A molding cushion material 1 according to claim 1 comprises a core layer 2 made of a material having rubber elasticity.
And fiber layers 3 formed on both sides of the core layer 2,
An intermediate layer 4 in which the core layer 2 and the fiber layer 3 intrude into each other is formed at a joint portion between the core layer 2 and the fiber layer 3, and the intermediate layer 4 is formed.
Is in the range of 10 to 70 μm.

The invention of claim 2 is characterized in that the core layer 2 of the molding cushion material 1 is made of fluororubber.

The third aspect of the invention is characterized in that the fiber layer 3 of the molding cushion material 1 is made of an aromatic polyamide nonwoven fabric.

According to a fourth aspect of the present invention, the storage elastic modulus of the core layer 2 of the molding cushion material 1 at 130 ° C. is 10%.
It is characterized by being in the range of -60 MPa.

According to the invention of claim 5, the ratio of the thickness of each fiber layer 3 to the thickness of the core layer 2 is such that the thickness of the fiber layer 3 is in the range of 1 to 10 when the thickness of the core layer 2 is 1. It is characterized by.

Further, the invention of claim 6 is characterized in that the thermal resistance of the molding cushion material 1 is 2500 to 5000 m ² ° C / W.

Further, according to the invention of claim 7, the elastic deformation amount at 170 ° C. when the compression pressure of 0.5 MPa is applied in the thickness direction to the compression pressure of 4 MPa is obtained. It is characterized in that it is in the range of 100 to 500 μm.

A method of manufacturing a laminated board according to claim 8 is
For the laminate 10 including the prepreg 8 and the metal foil 9,
It is characterized in that hot press molding is performed on a hot platen 13 via the molding cushion material 1 described in any one of 1 to 7.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

The core layer 2 is made of a material having rubber elasticity, and is not particularly limited, but fluororubber,
It can be formed of ethylene propylene rubber, hydrogenated nitrile rubber, silicone rubber, acrylic rubber, butyl rubber, or the like. Of these, when formed of fluororubber, deterioration (curing) due to heat during laminated plate molding is particularly small, and the effect of thermal history due to repeated use is small,
The durability can be remarkably improved.

The core layer 2 can be formed by molding an unvulcanized rubber compound for molding these rubbers into a sheet and vulcanizing it.

The rubber compound includes unvulcanized fluorine rubber, ethylene propylene rubber, hydrogenated nitrile rubber, silicone rubber, acrylic rubber, butyl rubber and the like.

Any suitable vulcanizing agent can be used as long as it can vulcanize unvulcanized rubber. Specific examples include organic compounds such as benzoyl peroxide and dicumyl peroxide. A peroxide-based vulcanizing agent, an amine-based vulcanizing agent such as triethylenetetrane, triethylenepentane, hexamethylenediamine, or a polyol-based vulcanizing agent can be used.

The compounding amount of the vulcanizing agent varies depending on the combination of the unvulcanized rubber and the vulcanizing agent and the physical properties required for the core layer 2, but preferably 100 parts by weight of the unvulcanized rubber. To 1 to 5 parts by weight.

If desired, a radical chain inhibitor (polymerization inhibitor), a peroxide decomposing agent, a lubricant, a metal oxide, a filler, a pigment, a vulcanization aid, etc. may be added to this rubber compound. be able to.

The radical chain inhibitor and the peroxide decomposing agent are added to improve the heat resistance and durability of the rubber. When these are compounded, the addition amount is 100% of the unvulcanized rubber. It is preferable that the total amount of the radical chain inhibitor and the peroxide decomposing agent is 5 to 15 parts by weight with respect to parts by weight.

A specific radical chain inhibitor is 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-hydroxybenzyl) which is a phenolic radical chain inhibitor. Benzene, product number “Adeka Stub AO-20” manufactured by Asahi Denka Co., Ltd., 3,9-bis [2
-{3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4-8,10-tetraoxaspiro [5,5] undecane, Asahi Denka Co., Ltd. product number "Adeka Stub AO-80" and the like, and thioether-based radical chain inhibitor pentaerythritol-tetrakis-
(Β-lauryl-thiopropionate), product number “ADEKA STAB AO-412S” manufactured by Asahi Denka Co., Ltd., and the like.

Specific peroxide decomposers include benzimidazole type peroxide decomposers such as 2-mercaptomethyl benzimidazole (product number "Nocrac MBZ" manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) and mercapto. Zinc salt of methylbenzimidazole (Part number "Vu
lkanox ZMB2 / C5 "), etc., cyclic neopentanetetraylbis (2,6-di-t-4-methylphenylphosphite), which is a phosphite-based peroxide decomposing agent, manufactured by Asahi Denka Co., Ltd. Stub PEP-36 "or the like can be used.

The vulcanization aid can be added in order to improve the vulcanization density to improve heat resistance and durability, and to reduce the occurrence of compression set. Specific vulcanization aids include tetrahydrofurfuryl methacrylate, methoxydiethylene glycol methacrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, ethylene dimethacrylate, 1,3-butylene dimethacrylate, 1,4-butylene dimethacrylate, 1,6 -Hexanediol dimethacrylate, polyethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-
Hexanediol diacrylate, 2,2'-bis (4
-Methacryloxydiethoxyphenyl) propane, 2,
2'-bis (4-acryloxydiethoxyphenyl) propane, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, triallyl isocyanurate, triallyl cyanurate, triallyl trimellitate, Diallyl phthalate, diallyl chlorendate,
Examples thereof include divinylbenzene, 2-vinylpyridine, N, N'-methylenebisacrylamide, 1,2-polybutadiene and the like.

The filler can be added to improve the heat resistance of rubber and to reduce the cost of the cushion material. This filler preferably has an average particle diameter of 0.1 to 100 μm, and when added, its addition amount is preferably 15 to 50% by volume based on the total amount of the rubber compound.

Specific fillers include inorganic materials such as glass beads, hollow glass beads, ceramic powder, organic materials such as aromatic polyamide powder, silicone resin powder, fluorine resin powder, phenol resin powder, and fossils such as mineral black. Materials, mineral materials such as fluorite, clay, etc. can be mentioned.

As the lubricant, stearic acid (product number "Lunack S30" manufactured by Kao Co., Ltd.) or the like can be used, and when added, the addition amount is 100 parts by weight of unvulcanized rubber. It is preferably 0.5 to 2 parts by weight.

Specific examples of the metal oxide include magnesium oxide (product number "Mug Sarat 30" manufactured by Kyowa Chemical Industry Co., Ltd.) and the like.
The addition amount thereof is preferably in the range of 10 to 30 parts by weight with respect to 100 parts by weight of unvulcanized rubber.

The pigment may be blended in any suitable amount for the purpose of coloring the core layer 2.

The fiber layer 3 preferably has a sufficient impact resistance, and can be formed of a fiber material 6 such as a non-woven fabric made of various fibers.

The fibers constituting the fiber layer 3 or the fiber material 6 are not particularly limited, but include polyamide fibers, aromatic polyamide fibers, polyimide fibers, polyamideimide fibers, polyester fibers, aromatic polyester fibers, polyarylate fibers, Fluorine fiber, acrylic fiber, organic fiber such as polyvinyl alcohol fiber, or inorganic fiber such as glass fiber, carbon fiber, slag fiber, lock fiber, ceramics fiber, metal fiber can be mentioned, and one kind of these fibers or Two or more kinds can be used in combination.

Particularly, it is preferable to form the fibrous material 6 from a non-woven fabric made of aromatic polyamide fiber because it has high heat resistance and little deterioration due to heat.

An appropriate method can be used to obtain a non-woven fabric (fiber material 6) from these fibers. For example, webs made of these fibers are laminated and entangled and integrated by needle punching. Obtainable.

Next, an example of manufacturing the cushioning material 1 for molding will be described.

The rubber compound 5 as described above is subjected to roll molding or the like to form the unvulcanized rubber sheet 5. The thickness of the rubber sheet 5 is preferably in the range of 0.25 mm to 1.5 mm.

Then, by arranging and laminating the fibrous material 6 on both sides of the required number of rubber sheets 5, the rubber sheet 5 and the fibrous material 6 are laminated and integrated by applying heat and pressure molding. 5 can be vulcanized and hardened to obtain a molding cushion material 1 as shown in FIG. For example, in the example shown in FIG. 2, the fiber material 6 is arranged on both sides of one rubber sheet 5 to be laminated and integrated. At this time, the core layer 2 in which the rubber sheet 5 is cured is formed, and the fiber layers 3 are formed on both sides of the core layer 2 with the fiber material 6. The molding conditions at the time of heat and pressure molding vary depending on the composition and thickness of the rubber compound, but the heating temperature is 170 to 180 ° C., the initial pressure is 0.5 to 1 MPa, and the molding time is 90 to 120 minutes. preferable.

Further, in manufacturing the molding cushion material 1, by embedding a reinforcing material made of a fiber sheet such as glass cloth in the core layer 2, it is possible to prevent the core layer 2 from breaking and to shrink the core layer 2. Can be suppressed. In this case, for example, in manufacturing the molding cushion material 1, in addition to the rubber sheet 5 and the fiber material 6, a reinforcing sheet 7 impregnated with a rubber compound is used.

For the reinforcing sheet 7, for example, the above rubber compound is dispersed in an appropriate solvent such as MEK (methyl ethyl ketone), and the fiber material 6 such as glass cloth is impregnated with this and dried to add no rubber compound. It can be obtained by volatilizing the solvent while maintaining the sulfurized state.

Then, as shown in FIGS. 3 and 4, a required number of rubber sheets 5 are arranged on both sides of the reinforcing sheet 7, and a fiber material 6 is further arranged on the outer side of the rubber sheets 5 to be laminated. By doing so, the rubber sheet 5 and the fiber material 6 are laminated and integrated, and the rubber compound in the reinforcing sheet 7 and the rubber sheet 5 are vulcanized and cured, and the molding cushion material 1 as shown in FIG. Can be obtained. For example, in the example shown in FIG. 3, one rubber sheet 5 is arranged on each side of one reinforcing sheet 7, and a fiber material 6 is further arranged on the outside of each of them to form a laminated body. In the example shown in FIG. 4, two rubber sheets 5 are arranged on both sides of one reinforcing sheet 7, and fibrous materials 6 are arranged on the outer sides of both sides to be laminated and integrated. At this time, the rubber compound in the reinforcing sheet 7 and the rubber sheet 5 are cured and the core layer 2 in which the reinforcing material is embedded
And the fiber layer 3 is formed on both sides thereof with the fiber material 6.
Is formed. The molding conditions at the time of heat and pressure molding can be the same as those described above.

A surface layer material may be provided on the surface of the molding cushion material 1. As the surface layer material, aromatic polyamide cloth or the like can be used, and in this case, it is possible to prevent defibering of fibers from the fiber layer and prevent adhesion of foreign matter to the laminate during molding of the laminate. .

In forming the molding cushion material 1 as described above, the thickness of the intermediate layer 4 (see FIG. 1 (b)) in which the fiber layer 3 and the core layer 2 are overlapped is in the range of 10 to 70 μm. To do so. That is, at the time of the above heat and pressure molding, the surface layer side of the fiber material 6 is embedded in the unvulcanized rubber sheet 5 at the interface where the rubber sheet 5 and the fiber material 6 come into contact, and the rubber sheet 5 is added in this state. By being vulcanized and cured, the core layer 2 is formed at the joint between the core layer 2 and the fiber layer 3.
And the fiber layer 3 intrude into each other to form the intermediate layer 4, and in the present invention, the thickness of the intermediate layer 4 is 10 to 10.
The range is 70 μm. Thereby, even if the molding cushion material 1 is repeatedly used during molding of the laminated plate, the elastic deformation amount of the molding cushion material 1 can be maintained for a long period of time, and the moldability of the laminated plate is improved over a long period of time. be able to. At this time, the thickness of the intermediate layer 4 is 10
If it is less than μm, sufficient bonding strength between the core layer 2 and the fiber layer 3 cannot be obtained, and the core layer 2 and the fiber layer 3 cannot be integrated. If this thickness exceeds 70 μm, the degree of reduction in elastic deformation due to repeated use increases, and it becomes difficult to use the product for a long period of time.

The thickness of the intermediate layer 4 can be adjusted by controlling the composition of the rubber compound forming the rubber sheet 5, the molding conditions, and the like. Specifically, it is an integral molding of the molding cushion material. The initial pressure at the time is set lower (preferably 0.5 to 1 MPa),
Vulcanization of the rubber sheet 5 is allowed to proceed to some extent prior to molding and integration, or the vulcanization rate at the time of integral molding is increased by controlling the compounding amount of the vulcanizing agent to increase the thickness of the intermediate layer 4. Can be controlled.

The core layer 2 is preferably formed so that the storage elastic modulus at 130 ° C. is in the range of 10 to 60 MPa. This storage modulus is JIS K7
Based on 198, it is measured by a non-resonance forced vibration method with a viscoelasticity measuring instrument. In this way, it is possible to further extend the life of the molding cushion material 1, and
It becomes possible to further improve the formability at the time of forming the laminated plate. If the storage elastic modulus is less than 10 MPa, the core layer 2 is likely to be damaged due to repeated use, and if it exceeds 60 MPa, the elastic deformation amount of the core layer 2 is reduced and the formability of the laminated sheet is sufficiently increased. There is a risk that it will not be obtained.

This storage elastic modulus can be adjusted by the composition of the rubber compound for forming the core layer 2, the heating and pressurizing conditions, etc. Specifically, the amount of the vulcanizing agent is adjusted. Alternatively, it can be adjusted by changing the type or the blending amount of the filler.

The thickness of the core layer 2 and the thickness of the fiber layer 3 depend on the materials forming the core layer 2 and the fiber layer 3, the physical properties required for the molding cushion material 1, and the like. 2 to 0.5 to 1.5 mm, each fiber layer 3 to 2.0 to 6.0 mm
It is preferable to form it to a thickness of. At this time, the thickness of the fiber layer 3 and the thickness of the core layer 2 each include the thickness of the intermediate layer 4.

The ratio of the thickness of each fiber layer 3 to the thickness of the core layer 2 is such that when the thickness of the core layer 2 is 1.
Is preferably formed so that the thickness thereof is in the range of 1 to 10. This makes it possible to further improve the moldability during molding of the laminated plate. Fiber layer 3 for this core layer 2
If the thickness ratio is less than 1, the ratio of the fiber layer 3 becomes too small, which may result in large in-plane pressure unevenness of the laminate 10 which will be described later at the time of molding the laminated plate, and uniform moldability is obtained. If the thickness ratio of the fiber layer 3 exceeds 10, the ratio of the fiber layer 3 becomes too large, and the thermal resistance of the molding cushion material 1 becomes large, so that the laminated cushion is not easily molded. Since the molding time is prolonged or the ratio of the core layer 2 is too small, the temperature distribution in the plane of the laminate 10 at the time of molding the laminated plate becomes large, and uniform moldability may not be obtained.

Further, the molding cushion material 1 is preferably formed so that the thermal resistance in the thickness direction is 2500 to 5000 m ² ° C / W. By doing so, it is possible to improve the formability of the laminated plate at the time of forming the laminated plate and to improve the efficiency of heat transfer from the hot platen 13 or the like through the forming cushion material 1 to shorten the forming time. it can. If this thermal resistance is less than 2500 m ² ° C / W, the heat transfer efficiency at the time of molding the laminated plate becomes too large and temperature unevenness easily occurs. The temperature distribution between the laminates 10 is likely to occur, uniform moldability is difficult to be obtained, and 5000 m ² ° C /
If it exceeds W, the heat transfer efficiency to the laminate 10 may not be sufficiently obtained, and the molding time may be prolonged.

The thermal resistance of the molding cushion material 1 is determined by the composition of the rubber compound for forming the core layer 2, the material of the reinforcing material when the reinforcing material is used, the material of the fiber layer 3, the core layer 2, the fiber. It can be adjusted by changing the dimensions of the layer 3 and the reinforcing material, and specifically, can be adjusted by changing the density of the fiber layer 3, for example.

Regarding the amount of elastic deformation in the thickness direction of the entire molding cushion material 1, at 170 ° C., a compression pressure of 0.5 MPa was applied in the thickness direction, and the compression pressure was changed to 4 MPa. It is preferable that the amount of elastic deformation when transferred is 100 to 500 μm. This prevents unevenness (pressure loss) in the pressure applied to the laminate 10 due to the deformation (with the mold) of the molding cushion material 1 when the molding cushion material 1 is repeatedly used during molding of the laminated plate. However, it is possible to further improve the formability of the laminated plate during repeated use. If the amount of elastic change exceeds 500 μm, the deformation of the cushioning material 1 for molding (with a mold) due to repeated use causes pressure unevenness (pressure loss) during molding of the laminated plate, and sufficient moldability cannot be obtained. If it is less than 100 μm, there may be a problem in moldability.

The elastic deformation amount of the molding cushion material 1 depends on the composition of the rubber compound for forming the core layer 2,
When using a reinforcing material, the material of the reinforcing material, the material of the fiber layer 3,
It can be adjusted by changing the dimensions of the core layer 2, the fiber layer 3 and the reinforcing material, and specifically, the density of the fiber layer 3 and the bonding between the core layer 2 and the fiber layer 3. The thickness of the intermediate layer 4 in which the core layer 2 and the fiber layer 3 intrude into each other at a portion is adjusted.

A process for manufacturing a laminated board using the molding cushion material 1 formed as described above will be described.

As a base material for producing the prepreg 8, an appropriate material used for producing laminated plates can be used. For example, inorganic fibers such as glass or polyamide fibers,
Those formed of organic fibers such as aromatic polyamide fibers, polyester fibers and polyacrylic fibers can be used, and woven cloth, non-woven cloth or mat of these fibers can be used.

As the resin varnish for producing the prepreg 8, an appropriate resin varnish used for producing laminated boards can be used. For example, epoxy resin, phenol resin, melamine resin, polyimide resin, aromatic polyether resin, etc. It is possible to use a resin containing the thermosetting resin as a main component and a curing agent, a coupling agent, a flame retardant, a filler, a solvent, etc., if necessary.

As the metal foil 9, a suitable material such as a copper foil is used, and the thickness thereof can be set to, for example, 12 to 70 μm.

As the molding plate 11, for example, a plate material such as a metal plate made of a material having rigidity and good thermal conductivity can be used. For example, a surface of a stainless steel plate or an iron plate having a thickness of 1 to 3 mm is plated with chromium. It is possible to use a mirror-finished plate.

In producing a laminated plate, as shown in FIG. 5, one or a plurality of prepregs 8 obtained by impregnating a base material with a resin varnish and drying it if necessary are further laminated on one side or Metal foil 9 such as copper foil on both outer surfaces
After forming the laminated body 10 by disposing, the laminated body 10 is sandwiched between the molding plates 11 and a plurality of sets are stacked to form the body 12 to be pressed.

Further, the above-mentioned molding cushion material 1 is arranged on both outsides of the body 12 to be pressed, and the molding cushion material 1 is arranged between the heating plates 13, and the molding plate 1 is interposed between the heating plates 13. The pressed body 12 is heated and pressed. By such heat and pressure molding, the resin of the prepreg 8 is completely cured, and the prepreg 8 and the metal foil 9 in each laminate 10 are cured.
And are laminated and integrated to obtain a laminated plate.

In addition, during the above-mentioned lamination molding, FIG.
As shown in FIG. 1, one or a plurality of prepregs 8 are stacked on the circuit surface side of the core base material 14 on which a circuit is formed on one surface or both surfaces of the insulating substrate, and a metal foil 9 is arranged on the outer side of the prepreg 8 and laminated. It is also possible to form the article 10 and heat and press mold the laminate 10 in the same manner as in the above case. In this case, a multilayer board is obtained as the laminated board.

In this way, when a laminated board is manufactured using the above-mentioned molding cushion material 1, the molding cushion material 1
Since the strain of the heating platen 13 is absorbed by the heating platen 13 and a uniform surface pressure is applied, uniform formability is obtained, and the same molding cushion material 1 is repeatedly used to form a laminated plate. It can be manufactured, and the cost reduction at the time of manufacturing a laminated board and the reduction of environmental load can be realized.

[0063]

Examples (Example 1) 100 parts by weight of unvulcanized butadiene-styrene rubber ("OS rubber" manufactured by Hiker Co.) and carbon black (RT Vanderblt)
Co. 20 parts by weight of "Thermax" manufactured by Inc.,
15 parts by weight of magnesium oxide (Showa Chemical Industry Co., Ltd., "Kyowakuma 30") and 1.5 parts by weight of a vulcanizing agent (peroxide, manufactured by NOF CORPORATION, "Perhexa 2.5B") are kneaded. An unvulcanized compound was prepared.

This rubber compound was roll-formed to form an unvulcanized rubber sheet 5 having a thickness of 0.5 mm.

Further, 120 parts by weight of MEK as a solvent was added to the above-mentioned rubber compound to prepare a glass substrate (“ASCO216LAS45” manufactured by Asahi Schwabel Co., Ltd.).
0 ") and heat-dried at 130 ° C. for 20 minutes to form a reinforcing sheet 7 in which the unvulcanized rubber compound was impregnated at a ratio of 50% by mass with respect to the total amount.

As the fiber material 6, webs made of aromatic polyamide fiber ("Conex" manufactured by Teijin Ltd.) were laminated and entangled and integrated by needle punching.
A product having a thickness of 4 mm and a basis weight of 1200 g / m ² was used.

Then, as shown in FIG. 3, the reinforcing sheet 7
After arranging one rubber sheet 5 on each side of each of the rubber sheets, and further arranging one fiber material 6 on the outer side of each of the rubber sheets 5 and laminating the fibrous materials 6,
It was hot pressed. At this time, the heating temperature is 180 ° C., the molding time is 100 minutes, and the pressing force is 1 MPa at the start of molding.
As a result, the pressure was increased to 4 MPa 30 minutes after the start of molding, and thereafter maintained at 4 MPa.

By this heat and pressure molding, the unvulcanized rubber sheet 5 and the unvulcanized rubber compound in the reinforcing sheet 7 are vulcanized and cured, and the rubber sheet 5,
The glass base material and the fiber material 6 were laminated and integrated to obtain the molding cushion material 1.

(Example 2) In place of the unvulcanized butadiene-styrene rubber and the vulcanizing agent, unvulcanized fluororubber (manufactured by Daikin Industries, Ltd., "Daiel G755C",
101.5 parts by weight of a polyol-based vulcanizing agent) was mixed to prepare a rubber compound, and as the fiber material 6, a web made of polyester fiber (trade name “Tetoron” manufactured by Teijin Limited) was laminated. A product having a thickness of 4 mm and a basis weight of 1200 g / m ² , which was entangled and integrated with a needle punch, was used. A cushioning material 1 for molding was obtained in the same manner as in Example 1 except for the above.

Example 3 In place of the unvulcanized butadiene-styrene rubber and the vulcanizing agent, unvulcanized fluororubber ("Daiel G755C" manufactured by Daikin Industries, Ltd.,
A cushioning material 1 for molding was obtained in the same manner as in Example 1 except that 101.5 parts by weight of a polyol-based vulcanizing agent was mixed to prepare a rubber compound.

(Example 4) A rubber compound was prepared by using an unvulcanized silicone rubber ("KE941-U" manufactured by Shin-Etsu Chemical Co., Ltd.) in place of the unvulcanized butadiene-styrene rubber. Further, as the fiber material 6, a web having a thickness of 6 mm and a weight per unit area of 1800 g / m ^{2 which} is obtained by laminating webs made of aromatic polyamide fibers (manufactured by Teijin Ltd., “Conex”) and entangled and integrated by needle punching is used. Using. A cushioning material 1 for molding was obtained in the same manner as in Example 1 except for the above.

(Example 5) A rubber compound was prepared by using an unvulcanized silicone rubber ("KE941-U" manufactured by Shin-Etsu Chemical Co., Ltd.) instead of the unvulcanized butadiene-styrene rubber. A rubber sheet 5 was formed in the same manner as in Example 1.

As the fiber material 6, webs made of aromatic polyamide fiber ("Conex" manufactured by Teijin Ltd.) were laminated and entangled and integrated by needle punching.
A product having a thickness of 2 mm and a basis weight of 600 g / m ² was used.

Then, as shown in FIG. 2, one fiber sheet 6 was placed on each side of one rubber sheet 5 and laminated, and then heat and pressure molding was performed. The molding conditions were the same as in Example 1.

By this heat and pressure molding, the unvulcanized rubber sheet 5 is vulcanized and hardened, and the rubber sheet 5 is also cured.
The fiber material 6 was laminated and integrated to obtain the molding cushion material 1.

(Example 6) Example 1 was repeated except that an unsulfurized state ("KE941-U" manufactured by Shin-Etsu Chemical Co., Ltd.) was used in place of the unsulfurized state butadiene-styrene rubber.
A rubber compound was prepared in the same manner as above, and an unsulfurized rubber sheet 5 having a thickness of 0.35 mm was formed from this rubber compound.

Using this rubber compound, a reinforcing sheet 7 was formed in the same manner as in Example 1.

As the fiber material 6, webs made of polyester fiber ("Tetron" manufactured by Teijin Ltd.) were laminated and entangled and integrated by needle punching, and the thickness was 3 m.
m and the basis weight was 900 g / m ² .

Then, as shown in FIG. 4, two rubber sheets 5 are arranged on both sides of one reinforcing sheet 7,
Further, one fibrous material 6 was placed on each of the outer sides of the fibrous material 6 and laminated, and then heat and pressure molding was performed. The molding conditions were the same as in Example 1.

By this heat and pressure molding, the unvulcanized rubber sheet 5 and the unvulcanized rubber compound in the reinforcing sheet 7 are vulcanized and cured, and the rubber sheet 5,
The glass base material and the fiber material 6 were laminated and integrated to obtain the molding cushion material 1.

(Comparative example 1)
The heating temperature was 180 ° C., the molding time was 100 minutes, and the applied pressure was 3 MPa from the start of molding to the end of molding.
A cushioning material 1 for molding was obtained in the same manner as in Example 3 except for the above.

(Comparative Example 2) The molding conditions for heat and pressure molding were as follows:
The heating temperature was 180 ° C., the molding time was 100 minutes, and the applied pressure was 3 MPa from the start of molding to the end of molding.
A cushioning material 1 for molding was obtained in the same manner as in Example 1 except for the above.

(Comparative Example 3) Using the rubber sheet 5 used in Example 3, one rubber sheet 5 was placed on each side of the reinforcing sheet 7 and laminated, and then hot pressing was performed. At this time, the heating temperature is 180 ° C and the molding time is 1
00 minutes, the pressure is 1 MPa at the start of molding,
After 30 minutes from the start of molding, the pressure was increased to 4 MPa,
After that, the pressure was maintained at 4 MPa.

On both sides of the cushion material formed only of the rubber sheet 5 and the reinforcing sheet 7 thus obtained,
The same fiber material 6 as in Example 3 was arranged.

(Evaluation test) a. Storage elastic modulus measurement The rubber sheet 5 used in each of the examples and comparative examples was molded under the heat and pressure molding condition of each example and comparative example, and the width: 5
A sample consisting of only the core layer 2 having dimensions of mm × length: 55 mm × thickness: 1 mm was obtained. For this sample, JIS K
Based on 7198, a viscoelasticity measuring instrument (manufactured by Seiko, part number "SSC-5000") was used by the non-resonance forced vibration method.
The temperature dispersion of dynamic viscoelasticity was measured under the conditions of a temperature rising rate of 5 ° C./s and a measurement frequency of 10 Hz to obtain a storage elastic modulus at 130 ° C.

B. Cushion amount measurement Autograph compression tester with a constant temperature bath (manufactured by Shimadzu Corporation,
Part number “AGS-500B”) is used to apply a pressure of 0.5 MPa in the thickness direction at 170 ° C. to the molding cushion material 1 obtained in each example and comparative example, and then 4 M
The amount of change when Pa pressure was applied was measured. Such measurement was performed on 10 samples for each of the examples and comparative examples, and the average of the measured values was evaluated as the cushion amount.

C. Measurement of thermal resistance For each example and comparative example, dimensions in plan view 500 mm × 5
Using the cushioning material 1 for molding cut to 00 mm, FIG.
As shown in FIG.
The molding cushion material 1 and the heat insulating material 17 (heat resistance Rd = 5000 m ² ° C / W) are arranged in order from the 5 side, and the thermocouple 18 is arranged between the molding cushion material 1 and the heat insulating material 17 to form the molding. Laminate 1 of cushion material 1 and heat insulating material 17
The temperature Ta of the heating plate 15 was kept at 180 ° C. and the temperature Te of the cooling plate 16 was kept at 30 ° C. while applying a pressure of 4 MPa to the heating plate 15 and the cooling plate 16.

After maintaining this state for 60 minutes, the thermocouple 18
The thermal resistance Rb in the thickness direction of the molding cushion material 1 was derived from the temperature Tc measured by the following equation (1).

Rb = (Ta−Tc) / (Tc−Te) × Rd (1) Note that this equation (1) is derived based on Ohm's law in the thermal circuit shown in equation (2) below. It is derived from the equations (3) and (4).

Q = (T1−T2) / R (2) Q: Heat flux (W / m ² ) T1: High temperature part temperature (° C.) T2: Low temperature part temperature (° C.) R: Thermal resistance (m ² ° C. / W) Rb = (Ta-Te) / Q-Rd (3) Rb = (Ta-Tc) / Q (4) d. Measurement of Thickness of Intermediate Layer The cushioning material 1 for molding of each Example and Comparative Example was cut in the thickness direction and the cross section was observed with a microscope to measure the thickness of the intermediate layer 4. Such measurement is performed on 10 samples for each of the examples and comparative examples,
The average of the measured values was evaluated as the thickness of the mid layer 4.

E. Moldability evaluation Epoxy resin varnish ("YDB5" manufactured by Tohto Kasei Co., Ltd.
00EK80 "100 parts by weight, Nippon Carbide Co., Ltd. dicyandiamide 3 parts by weight, Shikoku Kasei Co., Ltd. 2-ethyl-4-methylimidazole" 2E4MZ "
A glass cloth base material (“7628AS450S”, manufactured by Asahi Schwabel Co., Ltd.) was impregnated with 0.2 parts by weight of a diluent solvent “dimethylformamide” and “methylethylketone”) and dried to give a resin content (resin content) of 48%. A prepreg 8 in a semi-cured state was obtained.

Two prepregs 8 were stacked, and a copper foil having a thickness of 35 μm was arranged on both sides of the prepreg 8 to form a laminate 10.

20 sets of this laminate 10 were prepared, and the laminate 1
The pressed body 12 was obtained by stacking the molding plates 11 between 0 with the molding plate 11 interposed therebetween.

The cushioning material 1 for molding is arranged on both sides of this pressure-receiving body 12 and is arranged between the heating plates 13, and the pressure-receiving body 12 is heated and pressed by the heating platen 13 through the cushioning material 1 for molding. did. The molding conditions were a temperature of 170 ° C., a pressure of 3 MPa, and a molding time of 2 hours. Then, it was further cooled under the same pressure to obtain a laminated plate in which the respective laminates 10 were molded and integrated.

Using the same molding cushion material 1, molding of the laminated plate was repeated under the above molding conditions,
The copper foil of the laminate obtained at the 50th, 100th, 200th and 300th repetitions was removed by etching treatment, and the appearance was observed visually and using a magnifying glass, and the following evaluation criteria were used. evaluated. ◯: Mesling and void are not observed. Δ: Mesling is 1 mm or less and 2 or less per 1 m ² , and voids are 0.5 mm ² or less and 3 or less per 1 m ² . X: Mease rings are more than 1 mm, or 3 or more per 1 m ² , or voids are more than 0.5 mm ² or 4 or more per 1 m ² .

F. Glass transition temperature measurement: e. The copper foil on the surface of the laminate obtained by the evaluation of formability was removed by etching, and the glass transition temperature (Tg) was measured at a heating rate of 20 ° C./min using an inspection scanning calorimeter (DSC).
Was measured.

After cooling the laminated plate used for this measurement to room temperature, the glass transition temperature (Tg ') was measured again at the temperature rising rate of 20 ° C./min in the same manner, and the glass transition temperature (Tg') was obtained in the first measurement. The difference from the glass transition temperature (ΔTg = Tg′−Tg) was determined.

The results are shown in Tables 1 and 2 together.

[0099]

[Table 1]

[0100]

[Table 2]

As described above, in each example, Comparative Examples 1 and 2
Better results have been obtained. Further, in Comparative Example 3, excellent results are obtained in the above evaluation, but since the fibrous material 6 and the cushioning material are separate types, the handleability and the like are not good.

[0102]

As described above, the molding cushion material according to claim 1 comprises the core layer made of a material having rubber elasticity, and the fiber layers formed on both sides of the core layer. An intermediate layer in which the core layer and the fiber layer intrude into each other is formed at the joint portion with the layer, and the thickness of the intermediate layer is 10 to 70 μm.
Therefore, when the laminate including the prepreg and the metal foil is heated and pressed by the hot platen through the forming cushion when manufacturing the laminated plate, the strain of the hot platen is absorbed. It is possible to apply pressure with a uniform surface pressure to improve the moldability, and it has high durability, and even if the cushioning material for molding is repeatedly used during molding of the laminated plate, the cushioning material for molding is formed. The amount of elastic deformation of the material can be maintained for a long period of time, and the formability of the laminated plate can be improved over a long period of time.

According to the second aspect of the present invention, since the core layer of the molding cushion material is made of fluororubber, deterioration (curing) of the core layer due to heat at the time of molding the laminated plate is particularly small, and the core layer of the cushion material is repeatedly used. The influence of heat history is reduced, and the durability can be remarkably improved.

According to the third aspect of the present invention, since the fiber layer of the molding cushion material is made of an aromatic polyamide nonwoven fabric, the heat resistance of the fiber layer is improved, deterioration due to heat is suppressed, and durability is remarkably improved. It can be improved.

According to a fourth aspect of the present invention, in the molding cushion material, the storage elastic modulus of the core layer at 130 ° C. is 10 to 6.
Since it is in the range of 0 MPa, damage to the core layer can be suppressed by repeated use to achieve a longer life of the cushioning material for molding, and at the same time, sufficient cushioning properties can be imparted to the core layer to form a laminated plate. The moldability at that time can be further improved.

According to the invention of claim 5, the ratio of the thickness of each fiber layer to the thickness of the core layer is in the range of 1 to 10 when the thickness of the core layer is 1. It is possible to further homogenize the surface pressure at the time, suppress the extension of molding time and the occurrence of temperature unevenness, and further improve the moldability at the time of molding the laminated plate.

Further, the invention of claim 6 is a cushion for molding.
Thermal resistance of material is 2500-5000m ²℃ / W
Therefore, it is important to improve the formability of the laminate when molding the laminate.
Is transmitted from the hot platen, etc. through the cushioning material for molding.
It can improve heat transfer efficiency and shorten molding time.
It is something.

Further, in the invention of claim 7, the elastic deformation amount at 170 ° C. when the compression pressure of 0.5 MPa in the thickness direction is changed to the compression pressure of 4 MPa is obtained. Since it is in the range of 100 to 500 μm, deformation of the cushioning material for molding (with a mold) when the cushioning material for molding is repeatedly used at the time of molding a laminated plate.
This makes it possible to prevent unevenness (pressure loss) in the pressure applied to the laminate and further improve the formability of the laminate during repeated use.

A method of manufacturing a laminated board according to claim 8 is
1 to 7 for a laminate including a prepreg and a metal foil
In order to perform heat and pressure molding with a hot platen through the molding cushioning material described in any one of 1. above, the distortion of the hot platen should be absorbed by the molding cushioning material to apply pressure with a uniform surface pressure. It is possible to improve the moldability, and even when the molding cushion material is repeatedly used during molding of the laminated plate, the elastic deformation amount of the molding cushion material can be maintained for a long period of time. The moldability of the laminated plate can be improved.

[Brief description of drawings]

1A and 1B show an example of the structure of a cushioning material for molding, where FIG. 1A is a sectional view and FIG. 1B is a partially enlarged view of FIG. 1A.

FIG. 2 is a cross-sectional view showing an example of a manufacturing process of a molding cushion material.

FIG. 3 is a cross-sectional view showing another example of the manufacturing process of the molding cushion material.

FIG. 4 is a cross-sectional view showing still another example of the manufacturing process of the cushioning material for molding.

FIG. 5 is a cross-sectional view showing an example of a manufacturing process of a laminated board.

FIG. 6 is a cross-sectional view showing another example of a manufacturing process of a laminated board.

FIG. 7 is a cross-sectional view showing a method for measuring the thermal resistance of a molding cushion material.

[Explanation of symbols]

1 Cushion material for molding 2 core layers 3 fiber layers 4 Middle class 8 prepreg 9 metal foil 10 Laminate 13 hot plate

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4F100 AA18 AA37 AG00 AK17A                       AK47B AK47C AK73 AN02A                       BA03 BA04 BA06 BA10B                       CA03 DG01B DG01C DG15B                       DG15C EJ17 EJ42 EJ82                       GB43 JK07 JK07A JK11                 4F204 AH36 AJ03 AJ05 AJ09 FA01                       FA15 FB01 FQ17

Claims (8)

[Claims] 1. A core layer made of a material having rubber elasticity,
An intermediate layer having a fiber layer formed on both sides of the core layer and having the core layer and the fiber layer invading each other is formed at a joint portion between the core layer and the fiber layer, and the intermediate layer has a thickness of 10 ~ 70μ
A cushioning material for molding which is in the range of m. 2. The cushioning material for molding according to claim 1, wherein the core layer is made of fluororubber. 3. The cushioning material for molding according to claim 1, wherein the fiber layer is made of an aromatic polyamide nonwoven fabric. 4. The storage elastic modulus of the core layer at 130 ° C.
The cushioning material for molding according to any one of claims 1 to 3, which is in the range of 10 to 60 MPa. 5. The ratio of the thickness of each fiber layer to the thickness of the core layer is 1 to 10 when the thickness of the core layer is 1.
The cushioning material for molding according to any one of claims 1 to 4, characterized in that 6. A thermal resistance of 2500 to 5000 m ² ° C./W
The cushioning material for molding according to any one of claims 1 to 5, wherein 7. 0.5 M in the thickness direction at 170 ° C.
7. The elastic deformation amount when the compression pressure of Pa is applied to the compression pressure of 4 MPa is in the range of 100 to 500 μm. The cushioning material for molding described in 1. 8. A laminate comprising a laminate including a prepreg and a metal foil, which is heated and pressed by a hot platen via the cushioning material according to any one of 1 to 7. Method of manufacturing a plate.