JP2002144350A - Method for manufacturing friction material and sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a friction material having a desired shape, especially a non-plane shape, easily even without using a molding mold. SOLUTION: In the method for producing the friction material which is fitted to the fitting surface 1a of a friction part 1, a friction material composition is molded into a flexible sheet, the sheet 2 is stuck on the fitting surface of the friction part or a friction part model, and the composition stuck on the fitting surface 1a is cured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a friction material, and more particularly to a method for producing a friction material capable of easily producing a curved or other non-planar friction material, and a sheet-like material used therefor. About things.

[0002]

2. Description of the Related Art
BACKGROUND ART Friction materials (friction lining materials) used for friction braking of various machines, such as brakes for industrial machines and clutch plates, are manufactured by press molding using a molding die. A friction part is manufactured by adhering to a surface to be attached. For example, in a method for producing a friction material by a so-called resin molding method, a friction material composition in which a thermosetting resin and a friction modifier are mixed is preliminarily molded in a blanking die having a desired shape. The preform is put into a firing mold and cured while applying heat and pressure to produce a friction material having a desired shape in order to obtain a final product shape.

However, all of the conventional manufacturing methods require a molding (sintering) mold, and furthermore, the mold is required in accordance with the dimensions and shape of the friction material, so that there is a limit in cost reduction. Having. In particular, when manufacturing a non-planar (for example, curved) friction material used for a drum-type brake, etc., compared to a flat friction material used for a disc-type brake, the brake to which this is attached is used. Different molds must be manufactured for each shape of friction parts such as shoes. For example, a friction material like a drum type brake used for a winding device for raising and lowering a ship's anchor is manufactured. In such a case, the above problem is more remarkable.

[0004] Further, the above-mentioned resin mold preform is relatively brittle even though it has been molded to some extent, and also has a problem in operation that requires careful handling.

In view of the above, the present invention has been made in view of the above-mentioned conventional problems, and provides a method of manufacturing a friction material capable of easily producing a friction material having a desired shape without using a molding die. An object of the present invention is to provide a manufacturing method suitable for manufacturing a non-planar friction material. Another object of the present invention is to provide a sheet material for producing a friction material that can easily produce a friction material without using a molding die.

[0006]

Means for Solving the Problems And the present inventors,
As a result of intensive studies, they have found that the above-mentioned problems can be solved by the following means, and have completed the present invention. That is, the present invention is to form the friction material composition into a flexible sheet, apply a stress to the sheet, and bend the sheet.
The present invention relates to a method for producing a friction material in which the friction material composition is completely cured in this state. Furthermore, the present invention relates to a method for producing a friction material used by being attached to an attachment surface of a friction component, wherein the friction material composition is formed into a flexible sheet, The present invention relates to a method for producing a friction material in which a friction material is attached along a surface to which a friction part or a friction part model is attached, and the friction material composition attached to the attachment surface is completely cured.

In the manufacturing method of the present invention, since the friction material composition is formed into a flexible sheet, a stress is applied to the friction material composition or the sheet is applied to the surface to be attached. The object can be deformed and held in a predetermined shape, and by completely curing the object, a friction material having a predetermined shape can be manufactured. Therefore, a molding die for producing a friction material is not required. Although the shape of the friction material to be produced is arbitrary, in particular, the production method of the present invention is suitable for producing a non-planar friction material such as a curved shape, which was conventionally difficult to produce without a mold, For example, if a non-planar surface is used as the surface to be attached, the shape of the surface to be attached is directly reflected on the shape of the friction material, so that the surface of the friction component can be attached very easily and reliably. A friction material conforming to the shape of the above can be manufactured.

Further, the friction material composition in the method for producing a friction material is excellent in strength when a composition containing a thermosetting resin, a fibrous reinforcing material, a friction modifier and an elastomer is used, Handling is easy. As a further preferred embodiment, the thermosetting resin, the fibrous reinforcing material, the friction modifier and the elastomer are uniformly mixed, and the friction material composition is substantially solvent-free. This is also a preferred embodiment.

Further, the present invention comprises a composition in which at least a thermosetting resin, a fibrous reinforcing material, a friction modifier and an elastomer are uniformly mixed, and has a deflection rate of 100% or more measured according to JIS K6911. The present invention relates to a sheet-like material formed into a sheet-like material which can be cured to a bending rate of 90% or less by performing a heat treatment under predetermined conditions. Such a sheet-like material is excellent in its own strength and can be bent by human power, and is cured to the extent that it can be used as a friction material after heat treatment, and thus is suitable as a sheet-like material used in the above-mentioned production method.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The friction material composition used in the production method of the present invention is formed into a sheet having a predetermined thickness (a standing state at room temperature) at a stage where the curing is not completely completed (primary curing stage). In this case, a material that is flexible and does not show fluidity) and has flexibility (deformable by applying a force) is used. More preferably, a material that is hardly broken when formed into a sheet is used. As such a friction material composition, a composition obtained by kneading at least a thermosetting resin, a fibrous reinforcing material, a friction modifier, and an elastomer is preferable. Further, the composition contains substantially no solvent (substantially no solvent)
This is the most suitable because it can prevent product variations due to volatilization of the solvent during molding of the friction material.

The thermosetting resin of the friction material composition is not particularly limited, and may be granular, powdery, massive,
Examples thereof include liquid phenol resins, melamine resins, epoxy resins, acrylic resins, and urea resins. Examples of the fibrous reinforcing material include wollastonite, potassium titanate fiber, rock wool, ettringite, carbon fiber, glass fiber, masonry fiber, aramid fiber, and the like. Shaped reinforcements are preferred. For example, wollastonite, potassium titanate fiber, ettringite, and stone fiber are suitable.

Examples of the friction modifier include inorganic particulates or powders such as barium sulfate, graphite, carbon black, white carbon, calcium carbonate, clay, mica, talc, diatomaceous earth, antigolite, sepiolite, montmorillonite, and zeolite. Iron, copper, brass, bronze,
Examples thereof include particles or powders of metals or alloys such as zinc and aluminum, and organic particles or powders such as cashew dust, acrylic resin, and wood powder. These fibrous reinforcements and friction modifiers include silane coupling agents such as aminosilane coupling agents, epoxysilane coupling agents, alkoxysilane coupling agents, titanate coupling agents, and aluminum coupling agents. Alternatively, those surface-treated with various surface treatment agents such as silicone-based coupling agents may be used.

As the elastomer, various natural or synthetic rubbers and thermoplastic elastomers can be used. Particularly preferred are NR (natural rubber), NBR (nitrile rubber), BR (butadiene rubber), and SBR (styrene / butadiene). Rubber), CR (chloroprene rubber), I
R (polyisoprene rubber), ACM (acrylic rubber),
High styrene rubber, EPDM (styrene-propylene-
Diene copolymer).

An uncured friction material composition is prepared by kneading the thermosetting resin, the fibrous reinforcing material, the friction modifier, the elastomer, and other components that can be blended as required. be able to. The mixing ratio of these is not particularly limited, but the thermosetting resin 10
The mixing ratio is preferably 30 to 30 parts by weight, 20 to 70 parts by weight of the fibrous reinforcing material, 10 to 50 parts by weight of the friction modifier, and 10 to 45 parts by weight of the elastomer.

As described above, the amount of the thermosetting resin is 10 to 30.
By blending parts by weight, it is possible to improve the friction and wear characteristics while maintaining the mechanical strength after being completely cured. By blending the fibrous reinforcing material in an amount of 20 parts by weight or more, the friction and wear characteristics and the mechanical strength can be improved. By setting the amount of the fibrous reinforcing material to 70 parts by weight or less, other components can be added in a necessary amount. By blending the friction modifier in an amount of 10 parts by weight or more, desired friction and wear characteristics can be exhibited. When the amount of the friction modifier is 50 parts by weight or less, the necessary amount of other components can be added. By blending the elastomer in an amount of 10 parts by weight or more, a friction material composition having an appropriate extrudability (extrudable plasticity) can be prepared. Heat resistance and mechanical strength can be improved by setting the blending amount of the elastomer to 45 parts by weight or less.

Next, a method of manufacturing the friction material of the present invention will be described. <Friction material composition adjusting step> The components constituting the friction material composition are kneaded by a known kneader, mixer, roll, extrusion, or the like, and formed into a plate-like block with a roll or the like, or cut into strands. To form pellets. The kneading is performed until the friction material composition is sufficiently homogenized.

<Sheet forming step> The obtained block or pellets of the friction material composition are introduced into a press molding machine or the like, and heat-treated at a temperature and for a time such that the friction material composition is not completely cured. Then, a sheet having a predetermined thickness (substantially the same thickness as the friction material to be manufactured) is manufactured. Temperature conditions that do not completely cure,
Depending on the type of resin used, for example,
When the thermosetting resin is a phenol resin, 120 to 200
° C, 120-150 ° C for epoxy resin, 120-130 ° C for melamine resin, 120 for urea resin
To 180 ° C., and the processing time is generally about 1 to 2 minutes per 1 mm of the thickness of the sheet to be obtained. As described above, by forming the friction material composition according to the present invention so as not to be completely cured (primary curing molding), the friction material composition can be formed into a sheet-like material that does not exhibit fluidity at room temperature and has flexibility. It will be molded. In the obtained sheet-like material, the above-mentioned components constituting the friction material composition are uniformly mixed, and at least the above-mentioned components constituting the friction material composition are used alone (for example, even if there is no core material or the like). ),
It does not show fluidity in the state of standing at room temperature and has flexibility.

Specifically, a flexible sheet-like material which does not show fluidity at room temperature and is flexible is, for example, JIS.
The deflection rate measured according to K6911 is 100 to 20.
00%, preferably 100-1000%, of sheet moldings. Further, the size of the sheet is not particularly limited, but if it is too large, the yield is poor because scraps are formed when molding the friction material in the friction material forming step described later, and if it is too small, the material is removed. Since a plurality of sheet-like objects must be attached side by side when attaching to the attachment surface, it is preferable that the sheet-like objects are formed to have substantially the same size as the friction material to be obtained. The thickness of the sheet is not particularly limited and is appropriately designed, but is generally 50 mm or less, preferably 25 mm or less, and the lower limit is 1 mm.
The above is exemplified. If necessary, the sheet-like material may be embedded with a core material made of fiber such as aramid or glass.

<Friction Material Molding Step> The friction material molding step includes several embodiments described below. However,
The present invention is not limited to the following embodiments. [First Embodiment] In this embodiment, a friction material is formed by heating and curing a sheet-like material in a state of being sandwiched between a plurality of support plates arranged side by side. Specifically, FIG.
As shown in FIG. 2, the above-mentioned sheet is applied to the attachment surface 1a of the support plate 1 constituting the friction part 1 (or a model (friction part model) which is not the support plate itself but has the same shape as the support plate 1). The attachment is performed while the one surface 2a of the article 2 is arranged along the surface. The support plate 1 has an attachment surface 1a and an opposite surface 1b formed on substantially the same curvature surface. Further, the friction component 1 (or friction component model) is such that at least its adhered surface is not easily deformed when the friction material composition (sheet-like material 2) is completed. For example, iron, copper, Examples thereof include metals made of silver, nickel, tin, aluminum, and alloys thereof, and highly heat-resistant resins. When the sheet 2 is attached, if the entire surface of the attachment surface 1a cannot be covered with one sheet 2, the first sheet 2 is attached, and then along the end thereof. While attaching (with no gap), another sheet-like material 2 is attached to cover the attachment surface 1a with the sheet-like material 2. When one sheet 2 is larger than the attachment surface 1a, the sheet 2 is appropriately cut and attached to the attachment surface 1a.

Next, the opposite surface 1b of the other support plate 1 is brought into contact with the other surface 2b of the sheet material 2, and the attachment surface 1a of the second support plate 1 is Attaching is carried out along one surface 2a. This is repeated, and the support plate 1 and the sheet-like material 2 are alternately laminated. The components of the laminate are tightly attached to each other (for example, as shown by a dashed line in FIG. 1,
The bolts are inserted into the holes of the support plate 1 and fastened to each other), and the sheet 2 is sandwiched and pressed between the adjacent support plates 1.
Then, the bundle in which the plurality of support plates 1 and the sheet-like material 2 are bundled is heated to cause the unreacted material remaining in the sheet-like material 2 to react, and this is completely cured.

The conditions for completely curing the sheet 2 are as follows:
Depending on the type of resin used, for example,
160 to 250 when the thermosetting resin is a phenol resin
° C, 120-250 ° C for epoxy resin, 120-200 ° C for melamine resin, 1 for urea resin
The temperature is, for example, 20 to 250 ° C., and the processing time is, for example, about 5 to 20 hours. The obtained friction material is
For example, the flexural modulus measured according to JIS K6911 is 90% or less, the flexural strength is 10 MPa or more, and the flexural modulus is 0.5 GPa or more. Also, particularly preferably, the flexural modulus measured according to JIS K6911 is 70% or less, the bending strength is 40 Mpa or more, and the flexural modulus is 1.5 Gpa or more.

After the sheet 2 is completed, the cured product is removed from the surface 1a of the friction component 1 (the surface of the friction component model) to form a predetermined shape (curved shape). The manufactured friction material is manufactured. This curved friction material can be formed in a curved shape with the limit of the bending rate of the sheet-like material 2 as a limit. The obtained friction material may be subjected to post-processing such as polishing if necessary. The manufacturing method of the present invention is most effective when manufacturing a non-planar (for example, curved) friction material such as a drum shape as described above.
A flat friction material such as a disk can also be manufactured.

Finally, the manufactured friction object is fixed to the surface of the friction component prepared in advance by bonding with an adhesive or via a fastener such as a screw or a rivet. Will be manufactured. When a sheet-like material is attached to the surface to be attached of a friction part (not a friction part model) to complete it, it must be completely cured and not removed, but fixed as it is or via a fastener. May be used as a finished product.

According to this embodiment, not only a large number of friction materials can be manufactured at one time, but also the sheet-like material 2 is pressed by each support plate 1, so that the formed friction material can be formed without any particular pressing. The material is not likely to lose its shape.

[Second Embodiment] This embodiment is different from the first embodiment in that one friction material is manufactured by attaching a sheet-like material to the attachment surface 1a of the friction component 1. . First
Portions different from the first embodiment will be described, and portions that are not particularly described are the same as those in the first embodiment. Specifically, as shown in FIG. 2A, the friction component 1 having a curved attachment surface 1a
On the attachment surface 1a (or the attachment surface of the friction part model) of
A non-planar friction material is manufactured by applying the sheet-like material 2 while keeping the sheet-like material 2 along the surface, and then performing the treatment under the condition that the friction material composition is completely cured. FIG.
(B) shows a friction part 1 having a flat attachment surface 1a.
The sheet-like material 2 is adhered to the surface 1a to be attached along the surface, and then processed under the condition that the friction material composition is completely cured, whereby a flat friction material is manufactured. You.

As in the first embodiment, any of the friction materials is
A finished product of the friction component can be obtained as it is or fixed, or it can be removed and adhered or fixed to obtain a finished product of the friction component.

[Third Embodiment] This embodiment is an additional modification of each of the above-described embodiments.
The adhesive is applied to the surface to be attached or / and the sheet-like material 2 in advance when affixing to a. Hereinafter, only the added and changed parts will be described. In each of the above embodiments, an adhesive such as a thermosetting adhesive is applied to the attachment surface 1a of the friction component 1, and the one surface 2a of the sheet 2 is attached from above.
Therefore, an adhesive is interposed between the attachment surface 1a of the friction component 1 and the sheet 2 before the sheet 2 is completed. By heating and curing this, the friction material is completed, and the friction material and the attachment surface 1a are bonded. According to this aspect, after the completion of the sheet-like material 2, the obtained friction material is the attachment surface 1 of the friction part 1 (for example, a support plate).
Since it is bonded to a, the bonding or fixing operation can be omitted.

[Fourth Embodiment] The present embodiment is a modification in which a friction material or a model of a friction component is not used when a sheet-shaped material 2 is completely cured to produce a friction material having a predetermined shape. That is, the friction material is formed by completely curing the sheet-like material in a curved state. Hereinafter, only the changed portions will be described. Specifically, as shown in FIG.
The sheet 2 is formed in a predetermined size in accordance with the size of the friction material to be obtained, and both ends of the sheet 2 are gripped so that stress is applied to the center of the sheet 2. The friction material is curved so as to have a desired curvature, and is completely cured in that state. Further, as shown in FIG. 3 (b), the sheet-like material 2 is placed on the platforms 5 and 5 which are spaced apart from each other by a predetermined distance, and is placed on the center of the sheet-like material 2 by a weight 6 or the like. A load (stress) is applied to bend, and in this state, it is completely cured. The obtained friction material is attached to the mounting surface 1 of the friction component 1 as in the first embodiment.
It can be adhered or fixed to a to produce a finished friction part.

As described in the above embodiments, according to the method of manufacturing a friction material of the present invention, a friction material having a desired shape can be easily manufactured without using a molding die. In particular, when manufacturing a non-planar friction material such as a drum, conventionally, a molding die must always be produced for each type, but according to the manufacturing method of the present invention, the friction component Since the friction material can be manufactured by using the material itself as a mold, the manufacturing cost can be reduced, and it is particularly effective to manufacture the friction material as a one-piece product.

Further, by using the above-mentioned friction material composition in the production method of the present invention, it is possible to form not only a flexible sheet-shaped material but also to attach the sheet-shaped material to the surface to be attached or to bend the sheet-shaped material. Hard to break when completed, so
It can be handled easily.

[0031]

The present invention will be described in more detail with reference to the following examples. Preparation of friction material composition Phenolic resin (trade name “PR-12687”, manufactured by Sumitomo Durres Co., Ltd.), potassium titanate fiber (trade name “TISMO-D”, manufactured by Otsuka Chemical Co., Ltd.) as a fibrous reinforcing material , Nitrile rubber (NBR) as an elastomer (trade name “Ni
pol 1001 ", manufactured by Nippon Aeon Co., Ltd .; antigolite (trade name" RF-80 ", manufactured by Yutaka Sangyo Co., Ltd.) and barium sulfate (trade name" C-30 ") as friction modifiers
0 ", manufactured by Takehara Chemical Industry Co., Ltd.), sulfur, zinc white, and other vulcanization accelerators, plasticizers, and processing aids at the following mixing ratios in a pressurized kneader, and the temperature of 90 to 100 ° C. While maintaining the mixture, the mixture was sufficiently kneaded and passed through a roll to prepare a plate-like block.

The mixing ratio of nitrile rubber (NBR) 26.1 wt% phenol resin 19.3 wt% potassium titanate fiber 19.3 wt% antigorite 14.5 wt% barium sulphate 14.5% by weight sulfur 0.4 % By weight Zinc white 1.4% by weight Vulcanization accelerator 0.4% by weight Plasticizer 2.9% by weight Processing aid 1.2% by weight Total 100.0% by weight

Forming a sheet-like material A block comprising the above-mentioned friction material composition was put into a press molding machine and heated at 180 ° C for about 6 minutes to form a JIS 6911 test piece-shaped sheet-like material. Similarly, a total of five sheet materials were obtained.

Then, for each of the obtained sheets,
A bending test was performed according to the test method specified in JIS K 6911 (distance between supporting points: 60 mm, load speed: 3 mm / min). As a result, almost the same numerical value was shown for the five sheet-like objects. Table 1 shows the average value. Further, each sheet was subjected to a Charpy impact test according to a test method specified in JIS K 6911. Table 1 shows the average value. Next, each of the sheet materials was heated at 180 ° C. for 8 hours to react the unreacted material to completely cure it, and then subjected to a bending test in the same procedure as described above. The average value is shown in Table 1.

[0035]

[Table 1]

Molding of Friction Material A block of the friction material composition prepared above was put into a press molding machine and heated at 180 ° C. for 10 minutes to obtain a sheet having a thickness of 10 mm, a width of 100 mm and a length of 300 mm. This sheet-like material can be deflected by human power.
It was not damaged even if dropped from a certain height.

Next, the sheet-like material is placed on the surface (width 1) of the brake shoe to which the phenolic adhesive has been applied in advance.
00mm, length 300mm, curvature 200R)
The friction material composition was completely cured by heating at 180 ° C. for 8 hours while holding the surface of the sheet material with an iron.

According to the obtained friction material, JIS-D-44
When the friction performance was evaluated in accordance with No. 11, it showed a stable dynamic friction coefficient of approximately 0.5 up to 250 ° C., and it was confirmed that there was no problem in practical use.

[0039]

As described above, according to the method of manufacturing a friction material according to the present invention, a friction material having a desired shape can be easily manufactured without using a molding die. Therefore, since it is not necessary to manufacture a mold for each type of friction material, manufacturing costs can be reduced. Further, the sheet-like material according to the present invention can be easily bent by human power and is hardly broken, so that it can be easily handled, and is cured after the heat treatment, which is suitable for the above-mentioned production method.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a friction material forming step.

FIG. 2 shows another embodiment of a friction material forming step,
(A) is a perspective view showing a state where a sheet-like material is attached to a non-planar friction part, and (b) is a perspective view showing a state where a sheet-like substance is attached to a planar friction part. In both (a) and (b), the state where the friction material after completion is removed is shown by a two-dot chain line.

FIGS. 3A and 3B are side views showing another embodiment of a friction material forming step.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Friction parts, 1a ... Surface to which friction parts are attached, 2 ... Sheet-like object

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 101/00 C08L 101/00 C09K 3/14 520 C09K 3/14 520M 530 530F F16D 69/00 F16D 69 / 00R // B29K 21:00 B29K 21:00 101: 10 101: 10 105: 06 105: 06 B29L 31:16 B29L 31:16 (72) Inventor Eiji Shinya 170 Urata, Urata Soinin, Kaizuka City, Osaka (72) Inventor Shinichi Adachi 126-39, Makishima-cho, Uji City, Kyoto Prefecture Inside East Asia Chemicals Co., Ltd. (72) Inventor Kouji Sakane 3-2-1-21 Odori, Chuo-ku, Osaka-shi Otsuka Chemical 3J058 BA61 GA15 GA26 GA37 GA55 GA65 GA92 GA93 4F071 AA03 AA10 AA12 AB04 AB18 AB20 AB24 AD01 AE12 AE17 AF13 AH19 DA04 DA15 DA18 4F203 AA36 AA45 AB25 AD03 AD16 AE08 AG01 AG03 AH81 DA12 DB01 DC01 DH16 DL09 4F209 AA36 AA45 AB25 AD03 AD16 AE08 AG01 AG03 AH81 NA01 NB01 NG02 NK10 4J002 DA01AC03Z AC06Z AC07Z AC08Z AC09ZAW00 BG00W BG00W DA087 DA097 DA107 DC007 DE137 DE186 DE237 DF016 DG047 DJ006 DJ007 DJ037 DJ047 DJ057 DL006 FA04X FA046 FD20Y FD207 GT00

Claims (5)

[Claims] 1. A friction material composition is formed into a flexible sheet, and a stress is applied to the sheet to be curved,
A method for producing a friction material, wherein the friction material composition is completely cured in this state. 2. A method for producing a friction material used by being attached to an attachment surface of a friction part, comprising:
Formed into a sheet having flexibility, this sheet-like material is attached along the surface to be attached of the friction part or the friction part model,
A method of manufacturing a friction material, wherein the friction material composition attached to the attachment surface is completely cured. 3. The method for producing a friction material according to claim 1, wherein the friction material composition is a composition containing a thermosetting resin, a fibrous reinforcing material, a friction modifier, and an elastomer. 4. The method for manufacturing a friction material according to claim 2, wherein the attachment surface is non-planar. 5. A sheet comprising a composition in which at least a thermosetting resin, a fibrous reinforcing material, a friction modifier, and an elastomer are uniformly mixed, and having a flexure rate of 100% or more measured according to JIS K6911. By forming a sheet-like material and performing a heat treatment under predetermined conditions,
A sheet-like material that can be cured to a flexure of 90% or less.