JP2002206599A - Belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt with high performance which is not deformed even if it is used for a long time under a high load (high temperature, pressurization, elongation force). SOLUTION: This belt is made of polyimide resin and has a reinforcing body formed by winding polybenzobisoxazole fiber. It is effective for example a belt (transmission by compression or tension) for an automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt having a high degree of elongation, strength and elasticity which does not change even under repeated tension or compression operations at high temperatures, and a method for producing the same. The belt is very effective, for example, for a power transmission belt of an automobile engine.

[0002]

2. Description of the Related Art A belt known as a heat-resistant belt is disclosed, for example, in JP-A-60-36211 (A).
And JP-A-11-44346 (B). Japanese Patent Publication No. A relates to a seamless belt in which the surface of a tubular woven fabric obtained by weaving a carbon fiber, a polyimide fiber or a glass fiber in a woven structure lengthwise and breadthwise is coated with a fluororesin. On the other hand, No. B is an aramid fiber, a glass fiber or a carbon fiber as an insertion yarn, a polyester fiber, a polyamide fiber, an inlay knitted fabric obtained by knitting with a liquid crystal polymer or a polyimide fiber, an aromatic polyamide resin, an aromatic polyimide resin, Aromatic polyamide imide resin, aromatic polyester amide resin, polyether ether ketone resin, polyether sulfide resin, polyphenylene sulfide resin, polyethylene terephthalate resin, fluorine resin, silicone resin, polycarbonate resin, phenol resin or epoxy resin An endless power transmission belt obtained by coating is disclosed. The coating method described in each of these reports also discloses that the entire knitted or woven fabric is immersed (soaked) in a coating solution and dried.

[0003]

However, the belt disclosed in each of the above publications can obtain the belt desired by the present inventors regardless of the combination (fiber structure and its material, covering material, etc.). Absent. The requirement is that the belt rotates mainly at a high speed of at least 180 ° C. (in air), especially at a high speed for a long period of time (for example, 3000 r in a normal running of an automobile).
(approximately pm), the deformation (elongation) can be achieved even if the rotation method is a tension rotation that rotates the pulley by applying tension to the belt, or a pressure rotation that rotates by applying a pressing force to the belt. ) Or no wear (heat-resistant deformation under high load). Endless tubular processing is easy, and the resin coated thereon has good affinity with the fiber material and can be coated with sufficient adhesion (processability).

[0004]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above two requirements and to find a new belt with higher performance and quality.
The invention is as follows. (Claim 1) A belt made of a polyimide resin having a reinforcing body wound with polybenzobisoxazole fibers. (Item 2) The belt according to item 1, wherein a polyimide resin layer is provided on a front surface side and a back surface side of a polyimide resin layer having a reinforcing body wound with polybenzobisoxazole fibers. (Claim 3) A conductive agent is contained in at least one of the polyimide resin layers on the front surface side and the back surface side.
The belt described in. (Item 4) The belt according to Item 2 or 3, wherein a lubricant is contained in the polyimide resin layer on the front surface side and the back surface side. (Item 5) The belt according to any one of Items 2 to 4, wherein the polyimide resin layer on the back surface side is formed by a rotary casting method. Hereinafter, the present invention will be described in detail with the following embodiments.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION As a fiber material used for a reinforcing member, in particular, polybenzobisoxazole (hereinafter referred to as PBBO) is used.
Is called). By selecting this PBBO,
The heat deformation resistance under a high load during the rotation of the belt is significantly improved compared to any other heat resistant resin, and the affinity with the polyimide resin to be coated is good, and it can be easily coated with extremely high adhesion. Thus, the desired belt can be obtained. This PBBO is generally 4,4'-
An equimolar amount of dihydroxy-m-benzidine and an aromatic dicarboxylic acid or a derivative thereof (-carboxylic acid ester, -carbonyl chloride, etc.) is subjected to a polycondensation reaction (intramolecular and intermolecular reaction) in a solvent (for example, polyphosphoric acid). Is synthesized. Here, one aromatic dicarbonyl chloride is
A compound in which two carbonyl chloride is bonded to an aromatic group, a polycondensation reaction between the -OH groups and the -NH ₂ group of the benzidine. Specific examples include, for example, isophthaloyl chloride, 4,4'-carbonyl chloride-diphenylmethane, 4,4'-carbonyl chloride-diphenyl ether and the like. The molecular weight is such that the liquid crystal can be spun with sufficient spinnability, and the obtained fiber has high heat resistance of 180 ° C. or more and high elasticity (for example, 1000 cN / d) -high strength (for example, 30 c
N / d) is a molecular weight sufficient to express
This is generally around 30,000 to 70,000.

The cross-sectional shape of the PBBO fiber is not particularly limited, and is often circular. Fineness is generally 50
It is a monofilament or multifilament of 〜5000 d / 1 to 2,000 f, preferably a multifilament of 100 to 700 d. If the fineness is smaller than 50d, the surface smoothness of the belt surface is improved, but the belt strength is undesirably reduced. Conversely, if the fineness exceeds 5,000 d, the belt strength increases, but the surface smoothness of the belt surface deteriorates, which is not preferable. The reason why the multifilament is preferable to the monofilament is that the imide-based heat-resistant resin to be coated adheres more easily (because the adhesion area becomes larger) and the belt obtained finally has appropriate flexibility. Because it is effective to give

The number of twists of the PBBO fiber is 0 to 300 times /
m, preferably 0 to 100 times / m. A smaller number of twists is preferable because the fiber structure is easily unraveled and handling is difficult, but the belt strength and the surface smoothness of the belt surface are both excellent. If the number of twists is greater than 300 turns / m, the belt strength,
The surface smoothness of the belt surface is deteriorated, which is not preferable. There is no problem when using a PBBO fiber having no twist (no twist), but when using a twisted fiber, the S-twisted fiber and the Z-twisted fiber are alternately arranged to prevent meandering of the belt. Good.

Next, the polyimide resin will be described.
First, this polyimide resin is a heat-resistant (at least 180 ° C.) polymer in which at least an imide group bonded to an aromatic ring is a repeating unit. Therefore, this unit also includes a so-called aromatic polyamideimide in which an amide group bonded to an aromatic ring is also a repeating unit. Also, this aromatic ring may have only one or two phenyl groups,
An aromatic ring in which two phenyl groups are bonded by an ether bond, an alkylene bond, a carbonyl bond, or the like.

The polyimide resin is classified into a thermosetting or thermoplastic aromatic polyimide and an aromatic polyamide-imide. First, a thermosetting or thermoplastic aromatic polyimide basically has an equivalent of an aromatic diamine and an aromatic dicarboxylic dianhydride in N equivalent.
-It is obtained by a polycondensation reaction in an organic polar solvent such as methylpyrrolidone and dimethylacetamide. At this time, when the polyimide is thermosetting, the reaction is carried out at a low temperature of ordinary temperature or lower. This is because the reaction must be stopped at the stage of the precursor polyamic acid. Therefore, when coating with this, a two-step process of coating the polyamic acid solution, then desolvating and imidizing to coat the thermosetting aromatic polyimide is performed. In the case of thermoplasticity, even if the polycondensation reaction proceeds to imidization, the polycondensation is dissolved in the solvent, so that after coating, only the solvent is removed.
This thermoplastic character is represented, for example, by two ether bonds in the main chain,
C ₃ or more alkylene groups bond, expressed in the case where a carbonyl bond or the like.

The starting material of each polyimide is, for example, the following monomer. In the thermosetting, as aromatic diamine, p-phenylenediamine, 4,4'-diaminodiphenyl, 4,4'-diaminodiphenylmethane, 4,4 '
-Diaminophenyl ether and the like. On the other hand, as aromatic dicarboxylic dianhydride, pyromellitic dianhydride, 2,2
2 ', 3,3'-biphenyltetracarboxylic dianhydride, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride, bis (2,3-dicarboxyphenyl)
Methane dianhydride and the like. On the other hand, in thermoplasticity, aromatic diamines include bis [4- {3- (aminophenoxy) benzoyl} phenyl] ether, 4,4'-bis (3-aminophenoxy) biphenyl, and bis [4- (3-aminophenoxy). ) Phenyl] sulfone, 2,2′-bis [4
-(3-aminophenoxy) propane and the like. One aromatic dicarboxylic dianhydride is a combination of each of the above-mentioned acid dianhydrides.

Aromatic polyamideimide is generally thermoplastic by itself having one imide group and amide group. Therefore, even if the raw material is subjected to polycondensation reaction in the organic polar solvent to proceed to imidization at once, since it is dissolved in the solvent, this may be coated as a coating solution and the solvent may be removed. However two more ether bonds found in the case of the thermoplastic aromatic polyimide, C ₃ or more alkylene linkage and also has a carbonyl bond or the like, the more thermoplastic.

The raw materials of the polyamideimide are an aromatic tricarboxylic acid monoanhydride and an aromatic diamine. The former is represented by, for example, trimellitic acid monoanhydride, and the latter is any of the above aromatic diamines. It is. The polycondensation reaction is performed in an equivalent amount at room temperature or higher.

Among the polyimide resins described above, thermosetting aromatic polyimides are particularly preferred. This is because the finally obtained belt is provided with sufficient durability (the belt does not easily elongate), abrasion resistance and heat resistance. Although the same kind of polyimide resin is preferably used for the belt, a combination of different kinds of polyimide resins (such as those having different resins for the surface layer and the intermediate layer) or a resin composition obtained by blending different kinds of polyimide resins is used. It does not hinder.

At least one of the polyimide resin layers on the front side and the back side preferably contains a conductive agent to prevent charging of the belt. In the present invention, a commonly used conductive agent can be used. Among them, conductive carbon powder is particularly preferably used. Conductive carbon powder is selected because it is mixed with the forming raw material, and when it is manufactured by molding into an endless tubular film by a rotary casting method described below, the conductive carbon powder is uniformly dispersed throughout. Work more effectively. This is due to the fact that the bulk density is extremely smaller than other conductive agents. Also, it is easy to mix and disperse with the forming raw material, and the desired conductivity can be obtained with a relatively small mixing amount. Here, if the desired conductivity is represented by a volume resistance value, 10 ² to 10 ¹² Ω · cm, preferably 10 ² to 10 ⁵
Ω · cm. The charging of the belt is affected by the material of the pulley, the rotation speed, and the like when the belt is used, but if the volume resistance value of the belt is within the above range, the belt can be used without any practical problem.

The conductive carbon powder has various physical properties (electrical resistance, volatile matter, specific surface area, particle size, pH, etc.) depending on the raw materials (natural gas, acetylene gas, coal tar, etc.) and the production conditions (combustion conditions). Values, DBP oil absorption, etc.). With as little mixing and dispersion as possible,
Conductive carbon powder that can easily obtain higher conductivity, such as a material having a high conductivity index with a well-developed structure (this is often obtained by using acetylene gas as a raw material), or a conductivity index Although not so high, it is preferable to select a conductive carbon powder that contains a large amount of volatile components, such as lowering the pH value. However, the addition of a small amount, conductive carbon powder that can obtain higher conductivity, there is also a case where the conductivity to be imparted tends to vary, so do not hinder sufficient check in advance in that regard It is good to select an appropriate conductive carbon powder as described above. In this sense, if a specific mixing amount is exemplified, it is 3 to 20% by weight, preferably 3 to 10% by weight, based on the polyimide resin.

For improving the dispersibility of the conductive carbon powder, for example, a fluorine-based surfactant or the like may be added to the polyimide resin layers on the front and back sides. The amount of addition is about 1% by weight or less based on the polyimide resin, and is as small as possible.

The polyimide resin layer having a reinforcing body wound with PBBO fibers also has a function as an adhesive resin layer for firmly bonding the front side polyimide resin layer and the back side polyimide resin layer. is there. In order to prevent a decrease in adhesive strength, it is better not to add the above-mentioned conductive agent or the like to the polyimide-based resin layer having a reinforcing body in which PBBO fibers are wound. Also, addition of a conductive agent or the like is a negative factor in terms of affinity and adhesiveness with the polybenzobisoxazole fiber.

The thickness of the polyimide resin layer on the front side and the back side is 30 to 300 μm. If the thickness is less than 30 μm, the belt is weak and the belt is easily torn,
If the thickness exceeds 300 μm, the durability of the belt is improved, but the flexibility and flexibility deteriorate, which is not preferable. The thickness of the polyimide-based resin layer having a reinforcing body wound with PBBO fibers is 2
１５０150 μm. PBB when thickness is smaller than 2μm
If the adhesive strength with the O-fiber is insufficient, and if it exceeds 150 μm, the interlayer between the polyimide resin layer on the front side and the polyimide resin layer on the back side is likely to peel off, which is not preferable. The thickness of the entire belt varies depending on the purpose of use of the belt.
About 600 μm. The size of the belt is also about 150 to 300 mm in diameter and about 5 to 20 mm in width.

The polyimide-based resin layer having a reinforcing body in which PBBO fibers are wound has a structure in which PBBO fibers are wound around the polyimide-based resin layer at a pitch between fibers of 0 to 2 mm.
It has a structure in which BBO fibers are buried. If the inter-fiber pitch is too large, the reinforcing effect of the PBBO fiber is reduced and the strength of the belt is weakened. The conditions differ depending on the fineness of the PBBO fiber and the number of twists. Conversely, if the PBBO fiber is too tightly packed and wound, the adhesive strength with the polyimide resin layer is reduced, or the layer is indirect with the polyimide resin layer laminated on the surface. Since the adhesion may decrease, it is preferable to wind the PBBO fiber so that the distance between the PBBO fiber and the PBBO fiber is about 0 to 500 μm (0 is aligned). Polyimide-based resin and PBB in polyimide-based resin layer having reinforcement body wound with PBBO fiber
The ratio of the O fibers is such that the volume of the polyimide resin / the volume of the PBBO fibers = 5/1 to 1/2. If the proportion of the polyimide resin is more than 5/1, the reinforcing effect of the PBBO fiber is not sufficient, and if it is less than 1/2, the adhesion becomes insufficient, which is not preferable.

It can be said that the greater the belt strength, the better. However, in the present invention, the tensile breaking strength is 1500 to 4
000 N / cm. In evaluating the strength of the belt, it is important to conduct a test under conditions close to actual use. In the present invention, as shown in the examples, the heat-resistant deformation of the belt (whether or not there is a decrease in tension, Is also evaluated.

Next, the method for producing a belt of the present invention will be described by taking as an example the case where a thermosetting polyimide resin is used. 1. Formation of Polyimide-Based Resin Layer (Endless Film) on Back Side First, a predetermined amount of the above polyamic acid solution is injected while slowly rotating a casting drum of a rotary casting machine, and then rotated at a higher speed. By this rotation, the solution is uniformly cast and spread over the entire inner surface of the casting drum. While maintaining the rotation speed, the entire drum is heated and dried to imidize. The entire drum is cooled and demolded to obtain an endless film (hereinafter, referred to as an A body) to be a polyimide resin layer on the back surface side.
In addition, here, especially the polyimide-based resin layer on the back side is formed by a rotational casting method, but this has high roundness accuracy,
This is because it is a preferable method for obtaining a tough endless belt. Of course, this rotation casting method can also be used to form the polyimide resin layer on the front surface side, but it is not necessary to do so.

2-1. Formation of a polyimide resin layer having a reinforcing body wound with PBBO fibers. Is coated on a cylindrical mold, a predetermined amount of a polyamic acid solution is applied by spraying, and dried by heating. At this stage, the imidization is not completed but is kept in a semi-cured state. The endless film up to this point is referred to as a B body. 2-2. Winding of PBBO fiber The body B is rotated while being covered with a cylindrical mold, and the PBBO fiber is wound while applying tension. The endless film so far is referred to as a C body.

3. Formation of Polyimide Resin Layer on Front Side The body C is rotated while being covered with a cylindrical mold, and a predetermined amount of a polyamic acid solution is spray-applied, heated and dried to perform imidization. Spray this polyamic acid solution,
The step of heating and drying is repeated three times to form a polyimide resin layer on the surface side. Finally, it is cut to a predetermined width to obtain a belt. In this step, 2-1. In this case, the semi-cured polyimide resin layer dissolves, and the PBBO fiber wound under tension is buried in the inside thereof, and the adhesive strength is increased.

In the production of the above-mentioned belt, various additives may be added to the polyamic acid solution for forming the polyimide resin layer on the front side or the back side, if necessary. For example, better abrasion resistance is more desirable. One way to achieve this is to make the surface of the belt smooth. The specific method is, for example, a minute mixing of a powdery lubricant such as molybdenum disulfide, graphite, and fluororesin. The addition of smaller amounts is preferred as it merely adds abrasion resistance without substantially altering the properties of the belt itself. Among these lubricants, fluororesin powder is preferred. This is because a small amount of addition is sufficient and the surface layer is in a continuous dispersion state in a film form, so that abrasion resistance, lubricity and water repellency are excellent. Fluororesin has heat resistance of at least 180 ° C
Therefore, it is better to select from those exhibiting thermoplastic behavior.

There are various types of machines used in the rotary casting method, but the ones used in the present invention are as follows. A metal drum having an inner mirror surface (barriers for preventing liquid leakage are provided on the entire inner surface on both sides) is removably mounted on four rotating rollers. A far-infrared heater for heating is provided near the upper part of the drum, and an intake nozzle is provided in the drum to quickly discharge the organic polar solvent evaporated by heating. In order to automatically supply the raw material, a raw material supply nozzle that moves left and right in the drum is provided to constitute the whole.

2-1. Spraying in the formation of the polyimide-based resin layer having the reinforcing body around which the PBBO fiber is wound can be performed using a general-purpose spraying machine because the viscosity of the polyamic acid solution is small. On the other hand, 3. Spraying in forming the polyimide resin layer on the front side is performed using a nozzle having the following structure because the viscosity of the polyamic acid solution is large. The nozzle is a slit nozzle having a predetermined width, and has a mechanism capable of swinging right and left and freely changing the distance from the inner surface of the metal drum. The mechanism also horizontally moves left or right by a predetermined width in conjunction with the rotation speed. In the case of liquid discharge, the supply source is a compressed air or a gear pump because the discharge amount may be controlled simply by discharging from a nozzle of a predetermined size. However, in the case of spray discharge, it is necessary to form a spray. For this purpose, a double-structure nozzle is used in which a polyamic acid supply nozzle is provided in the center and a compressed air supply nozzle is provided so as to sandwich the nozzle from both sides. Of course,
In the spraying machine having these nozzles, the above 2-1. P
A polyimide resin layer having a reinforcing body wound with BBO fibers may be formed. In addition, the supply in the form of spray is different from the casting coating by centrifugal force, and does not require the high-speed rotation of the metal drum, and has an effect that the metal drum can be formed by slow rotation. Therefore, the conductive agent contained therein is not dispersed unevenly on the surface, but is uniformly dispersed throughout the belt.

[0027]

Next, the present invention will be described in more detail with reference to examples. In addition, the measuring method and the evaluation method in each Example are as follows. <Tensile breaking strength> The tensile breaking strength was measured according to JIS: K7113 using a test belt cut to a width of 10 mm. <Heat deformation resistance> The heat deformation resistance was measured by using a test belt cut to a width of 10 mm and stretching it over two pulleys having a diameter of 60 mm with a tension of 1000 N / cm at a speed of 3000 rpm in a 90 ° C atmosphere. , A decrease in belt tension at the time of rotation for a predetermined time (described in Table 1), cracks generated on the surface, and damage to the belt due to wear.

(Example 1) Inner diameter: 218.56 mm, width: 3
A 50 mm casting drum was placed on a rotating roller, and the casting was performed under the following conditions. Take 425 g of a polyamic acid solution (solid content: 18%) composed of biphenyltetracarboxylic dianhydride and 4,4-diaminodiphenyl ether, and add conductive carbon powder (trade name Ketjen Black E)
C) 3.5 g and 250 ppm of a fluorinated surfactant were added, and 191.5 g of N-methylpyrrolidone was further added and diluted (hereinafter referred to as a conductive polyamic acid solution). Automatic injection was performed while rotating inside the casting drum. When the injection was completed, the rotation speed was gradually increased while the temperature of the drum was raised to 130 ° C.
When the temperature reached 130 ° C., it was rotated at a constant speed of 350 rpm and maintained in this state for 2.5 hours. During the heating rotation, N-methylpyrrolidone which was sucked and evaporated in the drum was quickly exhausted. When 2.5 hours have passed, the heating was stopped, the temperature was cooled to room temperature, and stopped.
Body).

The obtained A-form was coated on a cylindrical mold having an outer diameter of 218.4 mm and heated with a hot-air dryer at 120 ° C. for 30 minutes, and then biphenyltetracarboxylic dianhydride and 4,4 were removed.
A 60 g solution of 30 g of a polyamic acid solution (18% solid content) composed of 4-diaminodiphenyl ether and 30 g of N-methylpyrrolidone for dilution was applied by spraying (air pressure 22 N / cm ² ), and dried at 120 ° C. The one so far is referred to as a B body.

The B-body, which is still covered with the cylindrical mold, has 1,
Polyparaphenylene benzobisoxazole (molecular weight 47000) obtained by polycondensation of 3-diamino 4,6 dihydroxybenzene and terephthalic acid is spun and stretched and heat-treated to obtain a 250 d / 166 filament PBBO.
The fiber is traversed (transversely moved) at 3 cm / min while applying a tension of 10 N, and the B-body is rotated at 85 rpm.
The PBBO fibers were wound together (fiber spacing: 0). The one up to this point is referred to as C body. After heating the obtained C-form with a cylindrical mold at a temperature of 120 ° C. for 30 minutes while covering it in a cylindrical mold, it was rotated at 40 rpm, and was prepared to mold the A-form from a slit nozzle moving at 8 mm / sec. The remaining 70 g of the conductive polyamic acid solution is sprayed, and the temperature is gradually increased while maintaining the rotating state.
Drying was performed at 0 ° C. for 30 minutes. After drying, 70 g of the conductive polyamic acid solution was sprayed and dried again under the same conditions, and then fired at 280 ° C. for 30 minutes. The process from spraying the conductive polyamic acid solution to baking at 280 ° C. for 30 minutes was repeated three times to obtain a tubular body having a thickness of 465 μm (the spraying of 70 g of the conductive polyamic acid solution was performed six times. Become.). Using the obtained tubular body as a belt, width 1
It was cut to 0 mm, and the tensile fracture strength and the heat deformation resistance were evaluated. The tube was placed in air at 200 ° C. for 25 minutes.
The expansion and contraction when the sample was allowed to stand for 24 hours under a load of 0 N / cm ² was measured. The result was no stretching.

[0031]

[Table 1]

(Example 2) A 500 d / 332 filament PBBO fiber was subjected to 3.8 N while applying a tension of 10 N.
Traverse (transverse) at cm / min, and move body B to 85r
pm, and the same procedure as in Example 1 was carried out except that the PBBO fibers were wound up with the PBBO fibers being aligned (fiber spacing: 0).
A μm tubular body was obtained. The obtained tubular body was cut to a width of 10 mm as a belt, and the tensile breaking strength and the heat deformation resistance were evaluated. The tubular body was placed in air at 200 ° C for 2 hours.
The expansion and contraction when a load of 50 N / cm ² was applied and left for 24 hours was measured. The result was no stretching.

(Example 3) A 250 d / 166 filament PBBO fiber was applied with a tension of 10 N to 4.5.
Traverse (transverse) at cm / min, and move body B to 85r
pm, PB so that the fiber spacing is about 250 μm
A tubular body having a thickness of 450 μm was obtained in the same manner as in Example 1 except that the BO fiber was wound. The obtained tubular body was cut to a width of 10 mm as a belt, and the tensile breaking strength and the heat deformation resistance were evaluated. The expansion and contraction when the tubular body was left standing for 24 hours under a load of 250 N / cm ^{2 in} air at 200 ° C. was measured. The result was no stretching.

[0034]

Since the present invention is configured as described above, the following effects can be obtained. For example, even if the belt is used for at least 180 ° C. in the air under strong tension or under high pressure for a long period of time, a highly durable belt having an unprecedented superiority has been obtained.

As a belt, for example, the use as a power transmission belt in the CVT of automobiles, which is expected to be promising in terms of environment and low fuel consumption in the future, has become a promising alternative to the current metal belt.

It can withstand use not only for power transmission belts but also for transporting articles under various severe conditions, and has become extremely promising for generating new demand.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a cross section of a belt according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 front side polyimide-based resin layer 2 polyimide-based resin layer 3 PBBO fiber wound reinforcement 4 back-side polyimide-based resin layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 5/04 CFG C08J 5/04 CFG F16G 1/00 F16G 1/00 D // B29K 79:00 B29K 79 : 00 105: 08 105: 08 B29L 29:00 B29L 29:00 C08L 79:08 C08L 79:08 F term (reference) 4F072 AA04 AA07 AA08 AB05 AB17 AB22 AD45 AE08 AF01 AF02 AF11 AG16 AH04 AH24 AL19 4F100 AA37 AK49B AK49C BA03 BA06 BA07 BA10B CA19B CA19C CA19H CA21B CA21C CA21H DA11 DG06A GB51 JK02 JK05 JK07 4F205 AA40 AB13 AB18 AD16 AG03 AG16 GA02 GB01 GB11 GC04 GN02 GN17 GW06

Claims (5)

[Claims] 1. A belt made of a polyimide resin having a reinforcing body wound with polybenzobisoxazole fibers. 2. The polyimide resin layer according to claim 1, wherein a polyimide resin layer having a reinforcing body wound with polybenzobisoxazole fibers is provided on the front side and the back side. belt. 3. The belt according to claim 2, wherein a conductive agent is contained in at least one of the front and back polyimide resin layers. 4. The polyimide resin layer on the front side and the back side contains a lubricant.
The belt described in. 5. The belt according to claim 2, wherein the polyimide resin layer on the back side is formed by a rotary casting method.