JP2832399B2 - Sliding member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding member comprising a shaft to be fitted and its bearing, for example, a journal and a journal bearing, a spline shaft and its bearing, etc.
The present invention relates to a sliding member whose sliding surface is lined with an extremely thin polymer film according to a monomer casting method.

[0002]

2. Description of the Related Art A low-viscosity polymerizable monomer or prepolymer is injected into a gap between a fitted shaft and a bearing, and then polymerized and cured to form an ultra-thin polymer resin film on its sliding surface. The so-called current reaction molding method for lining is conventionally known (Japanese Patent Application Laid-Open No. 60-1780).
No. 13 and JP-A-63-212518).

In this method, it is also possible to provide a resin lining layer directly on the metal surface of these sliding members. However, in order to increase the adhesive force between the resin lining layer and the metal surface, a sliding surface is previously provided with a primer. Rather than forming a resin lining layer thereon. Conventionally, commercially available primers such as silane-based and phenol-based primers have been used for the latter means.

[0004]

However, when a sliding member resin-lined by a conventional reaction molding method using such a conventional primer is applied to a drive system of a vehicle such as an automobile, a high temperature around the drive system is high. When the sliding operation is continued for a long time under a high torque condition due to the influence or invasion of water, there is a problem that the resin lining layer peels off from the sliding member. Further, when such a drive system is used, there is a problem that rust is remarkably generated on the surface of the sliding member.

[0005] The driving system of an automobile or the like is generally poor in operating environment, such as being exposed to high temperatures during operation and having a risk of water intrusion. Therefore, there has been a demand for enhancement of the adhesive force of the resin lining layer on the surface of the member and improvement of rust prevention performance so that no trouble occurs even when the sliding member is used in such a poor environment.

On the other hand, Japanese Patent Publication No. 17415/1985 discloses a reaction between a specific epoxy resin component (a ₁ ), a dicarboxylic acid (a ₂ ) and a secondary amine (a ₃ ) having a primary hydroxyalkyl group. And a polyisocyanate compound (A)
Disclosed is a method for producing a thermosetting resin, which comprises reacting (b ₁ ) with a product (B) obtained by reacting an isocyanate protective agent (b ₂ ). In addition, the publication describes a primer coating obtained by mixing methoxymethylated melamine or the like into the thermosetting resin.

However, since this primer coating has poor water resistance, the problem of peeling of the resin lining and generation of rust has not been solved even if it is applied to the above-mentioned application in a drive system of an automobile. .

The present invention has been made to solve such a problem, and an object of the present invention is to prevent the resin lining layer from peeling off even under long-time high-torque continuous operation, and to prevent rusting. An object of the present invention is to provide a sliding member which is less likely to occur and has excellent durability. Another technical problem is to increase the water resistance of the primer layer and further enhance the adhesive strength between the metal sliding surface of the sliding member and the resin lining layer.

[0009]

SUMMARY OF THE INVENTION The present invention is based on the reaction product of an epoxy resin and a block isocyanate, and uses a melamine resin and an epoxy silane coupling agent as primers for the above-mentioned applications. A composition newly contained in a proportion is used, applied to a sliding surface of a sliding member, and a resin lining layer (usually, a nylon rim layer) is formed thereon. .

In the sliding member according to the present invention, a primer is coated on the sliding surface of the sliding member, and then a ω-lactam liquid material,
In a sliding member having a resin lining formed on a sliding surface by providing a layer of a monomer casting liquid comprising a polymerization catalyst and a polymerization initiator on the primer layer and then performing polymerization and curing, the primer is It comprises a reaction product of an epoxy resin and a block isocyanate, a melamine resin and an epoxy silane coupling agent, and the melamine resin and the epoxy silane coupling agent each have a solid content ratio of 1/6 to 6 based on the reaction product. 1/3, 1/20
It is characterized in that it is contained at a ratio of 0 to 1/20.

(Summary of the Invention) A primer used in the present invention is prepared by adding a melamine resin and an epoxy-based silane coupling agent to an organic solvent solution of a reaction product of an epoxy resin and a block isocyanate based on a solid content ratio based on the reaction product. And 1/200 to 1/20, respectively.

As the epoxy resin, bisphenol A
Type epoxy resin, bisphenol F type resin, bisphenol S type epoxy resin and novolak type epoxy resin, and addition reaction products of these epoxy resins with polycarboxylic acids such as adipic acid, sebacic acid, dimer acid and phthalic acid. .

The block isocyanate used in the present invention is an isocyanate compound and an isocyanate protecting agent such as a lactam-based protecting agent (ε-caprolactam, γ
-Butyrolactam), alcohol-based protective agents (methanol, ethanol, isobutyl alcohol, etc.), phenol-based protective agents (phenol, p-tert-butylphenol, cresol, etc.)
When heated to 140 ° C. to 250 ° C., it dissociates to form a free isocyanate group.

The addition reaction in this case is usually carried out by heating a solution of the isocyanate compound in an inert solvent to 50 ° C. to 100 ° C., and dropping the isocyanate protective agent there. More preferably, the two are reacted at a ratio such that the ratio of the number of isocyanate groups of the isocyanate compound to the number of active hydrogens in the isocyanate protecting agent is 5: 1 to 5: 4.

Examples of the isocyanate compound include aliphatic or alicyclic diisocyanate compounds (for example, hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, etc.) and aromatic diisocyanate compounds (for example, Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and the like, and addition reaction products of these with polyol compounds (for example, ethylene glycol, trimethylolpropane, pentaerythritol, castor oil, and the like) are used.

The melamine resin used in the present invention is an alkoxymethylolated melamine, which is intended to react with a hydroxyl group present in a reaction product of the above epoxy resin and a block isocyanate to promote crosslinking. Typically, methoxymethylolated melamine and butoxymethylolated melamine are mentioned.

The epoxy silane coupling agent used in the present invention is a silane compound having an epoxy group in the molecule, and is characterized by γ-glycidoxypropyltrimethoxysilane and 6- (2,4 -Epoxycyclohexyl) ethyltrimethoxysilane.

A feature of the present invention is that a melamine resin and an epoxy silane coupling agent are contained in a primer in a solid content ratio of 1/6 to 1 based on a reaction product of an epoxy resin and a block isocyanate, respectively. / 3, 1 /
It is contained at a ratio of 200 to 1/20.

When the amounts of the melamine resin and the epoxy-based silane coupling agent are within the above ranges, a sufficiently high crosslinking density can be obtained on the surface of the primer and the water resistance of the entire resin lining can be improved. Even if the used sliding member is used for a long period of continuous high-torque sliding and under poor conditions where water can enter, the resin lining does not peel off.

On the other hand, if the blending amount of the melamine resin is too small, the crosslinking density on the primer surface becomes insufficient. (A polymerizable monomer solution such as a nylon monomer) and inhibits polymerization of the monomer. On the other hand, when the blending amount of the melamine resin is too large, the excess amount of unreacted methylol group generates formaldehyde gas during the polymerization reaction of the monomer casting liquid, which inhibits the polymerization reaction. Such polymerization inhibition forms a low-molecular-weight polymerization failure layer containing a large amount of a monomer casting liquid (nylon monomer) between the primer layer and the resin lining layer. This layer itself has a weak cohesive force, so that not only significantly reduces the adhesive force between the metal surface of the sliding member and the resin lining layer,
Due to the ingress of water or use under poor high humidity conditions, for example, the nylon monomer is hydrolyzed to aminocaproic acid, which causes corrosion of the sliding member metal.

If the amount of the epoxy-based silane coupling agent is less than the above range, the water resistance of the resin lining will not be satisfactorily improved, and the resin lining will peel off due to intrusion of rainwater or the like into sliding parts, In particular, in the case of a nylon rim having high water permeability, such peeling is likely to occur. Conversely, if the amount of the epoxy-based silane coupling agent is too large, it is not economically advantageous, but also weakens the cohesive force of the primer itself and decreases the adhesive force.

Next, the production of the primer used in the present invention will be described. The steps of producing the primer include reacting the epoxy resin and the block isocyanate in an inert organic solvent to obtain a resin solution as a product, and blending a melamine resin and an epoxy silane coupling agent into the resin solution. Consists of The ratio of the epoxy resin and the block isocyanate used is such that the ratio of the number of hydroxyl groups contained in the epoxy resin to the number of isocyanate groups in the block isocyanate is from 10: 1 to 1: 1, preferably from 5: 4 to The range is set to be 5: 1. The reaction in the step is usually performed at 50 ° C to 150 ° C.
The reaction is carried out until the isocyanate group is substantially absent at the temperature of, but in some cases, when the molecular weight reaches the desired value, the reaction is stopped by adding, for example, a monohydric alcohol, and the isocyanate group is removed. It may be left as it is. In the step, a melamine resin and an epoxy silane coupling agent are added to the resin solution of the reaction product obtained in the step at a solid content ratio of 1 based on the reaction product.
/ 6 to 1/3 and 1/200 to 1/20. The primer thus prepared may be used as it is, but further, if necessary, a rust-preventive pigment and other inorganic fillers, a flow regulator, a surfactant, an organic solvent, etc. were blended. It may be used in a form.

The primer produced according to the above method is used as follows. First, an appropriate coating method on one of the sliding members, for example, one of the sliding surfaces of the spline shaft or the spline bearing, for example,
The primer is applied to a dry film thickness of 1 to 50 μm by air spray, electrostatic spray and dip coating, and then applied at 150 to 250 ° C. for 5 to 6 μm.
Heat for 0 minutes to complete the crosslinking reaction of the primer layer.

Thus, the sliding member on which the primer layer is formed is fitted with the other sliding member on which the releasing agent is separately applied to the sliding surface, and then the monomer is poured into the clearance between the two members. The sliding member of the present invention is manufactured by injecting a liquid (inter alia, a liquid composed of the following ω-lactam liquid) and polymerizing and curing to form a resin lining layer. Incidentally, such a monomer casting method is disclosed in
It can be understood by referring to JP-A-60-178013, JP-A-63-212518, and the like.

In the sliding member of the present invention, the monomer casting liquid for forming the resin lining layer comprises an ω-lactam liquid, a polymerization catalyst and a polymerization initiator. As the monomer casting liquid, the following two examples of the monomer casting liquid are particularly preferable in relation to the primer used in the present invention.

The first example of a preferred monomer casting solution is an ester-bonded monomer casting solution having the following composition (hereinafter, referred to as monomer casting solution A). (A) an ω-lactam liquid containing a polymerization catalyst of an alkali metal or alkaline earth metal compound; and (B) a lactam polymerization initiator represented by the following formula:

[0027]

Embedded image

[0028]

Embedded image Or

[0029]

Embedded image (Wherein Z is a polypropylene oxide polyol, A
Is a hydrocarbyl group of aliphatic or aromatic, Q is a lactam residue having an alkylene group of C ₃ -C _11, t is at least 1, m is 0 or 1,
When m is 0, n is 0 or 1, and p is 1. When m is 1, n is in the range of 1 to 3, p = n, and R ₁
Is an alkyl group, an aralkyl group, an alkyloxy group, an aryloxy group, a halogen group or an aralkyloxy group. ) -Lactam liquid comprising at least one

Another example of a preferred monomer casting solution is an amide bond type monomer casting solution having the following composition (hereinafter, referred to as monomer casting solution B). (A) an ω-lactam liquid containing a polymerization catalyst of an alkali metal or alkaline earth metal compound; and (B) a lactam terminal group represented by the following formula:

[0031]

Embedded image

[0032]

Embedded image And / or

[0033]

Embedded image Wherein Q is a lactam residue having a C ₃ -C ₁₁ alkylene group, which is bonded to C, P or S via a nitrogen atom of the lactam, and A is an aliphatic or aromatic hydrocarbyl Or a hydrocarbyl ether group,
m is 0 or 1, and when m is 0, n is 0 or 1.
Wherein p is 1 and when m is 1, n is in the range of 1-3 and p = n, and R ₁ is an alkyl group, an aralkyl group, an alkyloxy group, an aryloxy group, a halogen Or an aralkyloxy group. ), And an elastic skeleton derived from a telechelic polyamine containing at least two primary or secondary amino groups, and a lactam polymerization initiator containing at least one lactam polymerization initiator. Stuff.

In the monomer casting liquid B, a more preferred lactam polymerization initiator is represented by the formula

[0035]

Embedded image

[0036]

Embedded image Or

[0037]

Embedded image Wherein Z is a primary or secondary selected from the group consisting of polyoxyalkylene polyamines, oxyalkylene copolymer polyamines, polyalkadiene polyamines, alkadiene copolymer polyamines, polyalkene polyamines, alkene copolymer polyamines and combinations thereof. A polyvalent group derived from a telechelic polyamine having at least two primary amino groups, t is at least 1, and A, Q, m, n and R ₁ are as defined above. It is.

The above lactam polymerization initiators are all
It can be produced by the reaction of an acyl lactam monomer having at least two acyl lactam groups with a telechelic polypropylene oxide polyol or a telechelic polyamine. In order to produce block copolymers of outstanding properties, at least 90 mol%, preferably 95%, of the hydroxyl groups of the polypropylene oxide polyol or the amino groups of the polyamine are converted to lactam end groups before the substantial lactam polymerization. It is better to let it.

The number average molecular weight of the lactam polymerization initiator is advantageously about 500 to about 15,000, more preferably about 1,000 to about 10,000, and particularly preferably about 2 to about 10,000.
000 to about 6000.

Advantageously, the number average molecular weight of the telechelic polypropylene oxide polyol or telechelic polyamine is from about 300 to about 10,000,
More preferably at least about 500, particularly preferably
Of at least about 1000.

The ω-lactam liquids include γ-butyrolactam, ε-caprolactam, ω-enantholactam, ω-caprylactam, ω-undecanolactam,
It refers to a single liquid such as ω-laurin lactam, and a mixture of one or more thereof.

The polymerization catalyst can be appropriately selected from those used for anionic polymerization of ω-lactam, and includes, for example, alkali metals and alkaline earth metals, hydrides, hydroxides, carbonates, alkylates thereof. , Arylated products, alkoxides and Grignard compounds.

[0043]

Embodiments of the present invention will be described below. In the examples, parts represent parts by weight. Example 1 (a) Preparation of primer Epoxy resin (Epototo YD-0 manufactured by Toto Kasei Co., Ltd.)
17 Epoxy equivalents 1960), 784 parts of xylol 78.
After dissolving in 4 parts and 196 parts of cellose, 25.1 parts of azelaic acid and 13.3 parts of diethanolamine were added, and the mixture was reacted at 140 ° C. for 4.5 hours under N ₂ gas. Then, when the acid value of the resin solid content reached 1.2 KOH mg / g, 314 parts of xylol and 245 parts of methyl isobutyl ketone were added, and then cooled to obtain a product (A). Separately, to 375 parts of cellose, 224 parts of hexamethylene diisocyanate and 151 parts of ε-caprolactam were added and reacted at 100 ° C. for 3 hours to obtain a product (B). Next, 165 parts of product (A) was added to 165 parts of product (A).
5 parts and 26.3 parts of xylol were added, and 1 part under N ₂ gas was added.
After reacting at 00 ° C. for 3 hours, 19.4 parts of methyl isobutyl ketone was added and then cooled to obtain a thermosetting resin solution having a solid content of 40%.

Further, 12 parts of rutile type titanium oxide and 10 parts of strontium chromate were sufficiently kneaded with 100 parts of the thermosetting resin solution using a three-roll mill, and then 10 parts of methokimethylolated melamine and γ-glycidate were mixed. One part of xypropyltrimethoxysilane was added. Then, a primer was prepared by diluting this solution with a 1: 1 mixed solvent of cellose / xylol until the solution had a viscosity of 100 centipoise (25 ° C.).

(B) Manufacture of sliding member A spline shaft having the specifications shown in Table 1 below and its bearing were used as sliding members. The primer prepared in (a) was coated on the sliding surface of the spline shaft by an appropriate coating method, and a release agent was applied to the sliding surface of the spline bearing. Next, the spline shaft and its bearing are fitted, and the monomer casting liquid A is injected into the clearance between the two.
Next, the resin was polymerized and cured by heating to form an extremely thin resin lining (a resin lining layer is laminated on a primer layer) on the sliding surface of the spline shaft.

[0046]

[Table 1] Example 2 The sliding member of Example 2 was manufactured according to the same procedure as described in Example 1 (b), except that the monomer casting liquid B was used instead of the monomer casting liquid A. . The primer used in Example 1 (a) was used as the primer.

Test Example—Adhesion Test— As shown in FIG. 1, the manufactured sliding member 2 was placed in a receiving jig 1 so that the member 2 was supported only by its resin lining, and then punched. 5, the sliding member 2 was punched out, the load P applied at that time was measured, and the load P was evaluated as a reading indicating the adhesive force. In FIG. 1, 3 represents a resin lining layer, and 4 represents a primer layer.

Initial adhesive strength at the time of production, and 7
After immersion in hot water at 0 ° C. for 24 hours, the adhesive strength after deterioration was measured. The sliding members of each example were tested, and for comparison, similar tests were performed on the following examples.

Comparative Example 1 A primer was prepared in the same manner and under the same procedure as in Example 1 (a) except that the blending amount of methoxymethylolated melamine was 15 parts. ), A sliding member was manufactured.

Comparative Example 2 A primer was prepared in the same manner and under the same procedure as in Example 1 (a) except that the blending amount of methoxymethylolated melamine was 5 parts. According to the procedure described above, a sliding member was manufactured.

Comparative Example 3 A primer was prepared under the same conditions and procedures as in Example 1 (a) except that γ-glycidoxypropyltrimethoxysilane was not used, and this was used to prepare a primer in Example 1 (b). ), A sliding member was manufactured.

Comparative Example 4 A primer was prepared in the same manner and under the same procedure as in Example 1 (a) except that 10 parts of γ-glycidoxypropyltrimethoxysilane was blended, and this was used to prepare a primer.
A sliding member was manufactured according to the procedure of (b).

Comparative Example 5 A primer prepared according to the same conditions and procedures as in Example 1 (a) was coated on a metal sliding surface of a sliding member, and the member was immersed in a container containing nylon 11 powder. Then, heating was performed to produce a sliding member in which the primer layer was powder-coated with nylon.

Control Example A primer was not applied in advance, and the procedure of Example was followed.
Sliding members were manufactured by the current reaction molding method.

Conventional Example 1 Using a commercially available silane coupling primer, a sliding member was manufactured by a conventional reaction molding method according to the procedure of the example.

Conventional Example 2 A sliding member was manufactured by a conventional reaction molding method using a commercially available phenolic primer and according to the procedure of the example.

FIG. 2 shows the results of these tests. From FIG. 2, it can be seen that the sliding member of the example has remarkably improved both the initial adhesive strength and the adhesive strength after deterioration.

-Actual vehicle running test-Each sliding member is incorporated as a torque transmission component into the drive system of an automobile, and actual vehicle running tests on submerged and undulating roads are performed for short, medium and long distances respectively. The presence or absence of peeling and generation of rust were examined. Table 2 shows the results.

[0059]

[Table 2] From Table 2, it can be seen that the sliding member of the example was subjected to such a rough road running test under the condition of long-time high-torque continuous sliding.
It can be seen that peeling of the resin lining does not occur and rust is hardly generated.

[0060]

As described above, according to the present invention,
The water resistance of the primer layer is further enhanced, and the adhesive strength between the metal sliding surface of the sliding member and the resin lining is remarkably enhanced. Therefore, even under a long-time high-torque continuous operation, the peeling of the resin lining does not occur. A sliding member that does not occur, hardly generates rust, and has excellent durability is provided.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method of testing an adhesive force of a resin lining on each sliding member.

FIG. 2 is a graph showing the results of an adhesive strength test of a resin lining on sliding members of Examples and Comparative Examples.

[Explanation of symbols]

 2 Sliding member 3 Resin lining layer 4 Primer layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16C 33/20 F16C 33/20 // B29K 77:00 B29L 31:00 (72) Inventor Seiichi Matsuo Awaji, Higashiyodogawa-ku, Osaka-shi, Osaka JP-A-2-266905 (JP, A) JP-A-63-212518 (JP, A) JP-A-60-178013 (JP, A)

Claims (1)

(57) [Claims] 1. A primer is coated on a sliding surface of a sliding member, and then a layer of a monomer casting liquid comprising an ω-lactam liquid, a polymerization catalyst and a polymerization initiator is provided on the primer layer, In a sliding member in which a resin lining is formed on a sliding surface by curing, the primer comprises a reaction product of an epoxy resin and a block isocyanate, a melamine resin and an epoxy silane coupling agent, The sliding wherein the resin and the epoxy silane coupling agent are contained at a solid content ratio of 1/6 to 1/3 and 1/200 to 1/20, respectively, based on the reaction product. Element.