JP3300699B2 - Metal fitting for oil seal member and oil seal member using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal fitting for an oil seal member and an oil seal member using the same, and more particularly, to an oil excellent in fluorohydrocarbon resistance used in an air conditioner or a refrigerator. The present invention relates to a seal member fitting and an oil seal member using the same.

[0002]

2. Description of the Related Art Many oil seal members are used for cooling devices such as refrigerators, refrigerators, and air conditioners, and compressors of air conditioners to seal refrigerant and refrigerating machine oil. Various types of such oil seal members are known. Among them, those having a vulcanized adhesive layer formed by applying and baking a vulcanized adhesive to an oil seal member bracket, and those having not been vulcanized. BACKGROUND ART An oil seal member manufactured by vulcanizing and bonding a sulfur preform to a rubber preform for an oil seal member and forming the rubber preform into a rubber molded product is generally known. The above-mentioned metal fitting for an oil seal member refers to a metal fitting made of a cold-rolled steel plate or the like that has been subjected to a chemical conversion coating treatment.

[0003] Among the above oil seal members, the use atmosphere of an oil seal member used for a shaft of an air conditioner machine or a refrigerator for a vehicle such as an automobile is becoming severer year by year. For example, in a vehicle air conditioner or a refrigerator, CFC12 (CCl2) is conventionally used as a refrigerant.
₂ F ₂₎ has have been used primarily, but in recent years the destruction of the ozone layer by chlorofluorocarbons is the environmental issues to destroy the ozone layer in place of the CFC12 HFC134a (CH ₂ FCF ₃₎
Fluorohydrocarbons have been used. Therefore, the rubber molded product of the oil seal member has excellent hardness, elongation, tensile strength, heat resistance, and oil resistance.
Further, in addition to various properties such as a small compression set, it is further required to have resistance to a fluorocarbon which is a refrigerant such that cracks and blisters are hardly generated.

[0004] For example, since an air conditioner for a car is used in an engine room of a car, the temperature of its use environment reaches 140 to 150 ° C. Conventionally used oil seal members, when used under such severe conditions, the occurrence of blisters and cracks near the bonding interface between the vulcanized adhesive layer and the chemical conversion film is recognized, The fluorohydrocarbon resistance at the above temperature was insufficient. Therefore, the adhesive interface of the used oil seal member is required to have heat resistance in a 150 ° C. environment and fluorocarbon resistance in a 150 ° C. environment.

[0005] In the future, it is considered that the use environment of an oil seal member for an air conditioner machine for a vehicle or a refrigerator will be more severe, and a stable adhesive property with the vulcanized adhesive layer will be maintained. With a conversion coating that can
It is desired to develop a metal fitting for an oil seal member and an oil seal member having better sealing characteristics.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to
An oil seal member provided with a film having excellent fluorohydrocarbon resistance even in an environment of 0 ° C. and capable of maintaining a stable adhesive property between a vulcanized adhesive layer and an oil seal member used therefor It is to provide metal fittings.

[0007]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies and as a result, they have found that the object can be achieved by performing a specific chemical conversion treatment on metal fittings. The present invention has been completed. The present invention has the following features. (1) It is made of a crystal having a particle size of 80 μm or less and has an average thickness of 0.1 μm.
Oil seal member bracket, characterized in that it comprises at least part of its surface a phosphate coating having a uniform one thickness of 5 to 10 [mu] m. (2) The metal fitting for an oil seal member according to the above (1), which is used for an oil seal member of at least one of a refrigerator and a compressor for a car air conditioner. (3) The metal fitting for an oil seal member according to the above (1) or (2) and the rubber composition for molding an oil seal member are vulcanized and bonded via a vulcanized adhesive layer in contact with the phosphate film. An oil seal member comprising:

[0008]

FIG. 1 is a simplified cross-sectional view showing a preferred example of an oil seal member 1 using an oil seal member 2 of the present invention. As shown in FIG. 1, the oil seal member 1 includes an oil seal member fitting 2,
This is a member formed by vulcanizing and bonding a rubber molded product 3 for an oil seal member. The metal fitting 2 for an oil seal member is basically a metal fitting 5 having a phosphate film 4 on at least a part of its surface 5a.

Examples of the phosphate coating 4 include a zinc phosphate coating, a zinc calcium phosphate coating, an iron phosphate coating, and a manganese phosphate coating. A system coating is preferred.

The phosphate film 4 has a uniform thickness of the average thickness D1. The average thickness D1 is 0.5 to 10
μm, and preferably 1 to 8 μm. Here Hitoshi first and refers to be uniform in terms of including a manufacturing error. The above manufacturing error is specifically caused by the phosphate film 4
Difference between the maximum thickness and the minimum thickness is preferably 1.0
μm or less, and more preferably 0.5 μm or less. As a result, when the coating 4 is formed to have an uneven thickness, in other words, when the difference between the maximum thickness and the minimum thickness of the coating 4 exceeds 1.0 μm , As a result, the corrosion resistance of the metal fitting 5 can be favorably maintained.

The average thickness D1 is 0.5 to 8 g / m ² , preferably 2 to 6 g / m ² , per unit area.
m ² . If the weight of the film is less than 0.5 g / m ² , the film 4 will be formed non-uniformly, and the corrosion resistance of the metal fitting will be poor. If the coating weight exceeds 8 g / m ² , the crystals become very large and become porous, and there is a problem that the adhesive is peeled off due to the destruction of the coating. Coating weight per unit area of such a film 4, for example, 75 ° C. to CrO ₃ 5% aqueous solution, 15
By immersing for a minute and dissolving the film,
It is calculated from the weight difference before and after peeling.

The phosphate forming the film 4 is composed of crystals having a particle diameter of 80 μm or less, preferably 20 μm or less. Preferred shapes of the crystals include needles, grains, and the like. When the particle size exceeds 80 μm,
Poor adhesion of the film, causing adhesive peeling. The particle size refers to the length of the crystal in the longest direction, and is measured, for example, by observation with an electron microscope or the like. The crystals preferably have a particle diameter of 5 μm or more.

The metal material of the metal fitting 5 includes, but is not particularly limited to, a cold-rolled steel sheet and a rolled steel material for general structure, which are generally used as metal fittings for an oil seal member, but is preferably a cold-rolled steel sheet. The metal fitting 5 is obtained by subjecting the above metal material to metal press working or the like in accordance with the desired shape and size.

The phosphate film 4 is provided on the surface 5 a of the metal fitting 5.
It is formed by subjecting a chemical conversion film to a treatment. In this chemical conversion film treatment, film characteristics such as film thickness, crystal shape and crystal size change depending on various conditions such as the treatment step, type of chemical, concentration, temperature and time. The phosphate film 4 according to the present invention is suitably formed by a chemical conversion film treatment method having each of the steps of alkali degreasing, water washing, surface conditioning, film formation, water washing, and drying, which are generally performed in the art. Temperature in each of the above steps,
Conditions such as the reaction time vary depending on the drug used, and are appropriately selected. By performing such a surface treatment on the metal fitting 5, the metal seal 2 for the oil seal member of the present invention is suitably manufactured.

As shown in FIG. 1, the oil seal member 1
The metal fitting 2 for the oil seal member and the rubber molded product 3 for the oil seal member are vulcanized and bonded via a vulcanizing adhesive layer 6 in contact with the phosphate film 4. As the rubber molded product 3 for an oil seal member, an unvulcanized rubber molded product generally used widely in this field and excellent in fluorocarbon resistance, heat resistance and oil resistance is used. Examples of such a rubber molded product include a rubber molded product obtained by molding a rubber composition containing a hydrogenated nitrile rubber as a main component. Among them, a bound acrylonitrile amount is 30 to 40% by weight, and an iodine value is 7 to 40%. 16 (mg / 100mg) and a hydrogenated nitrile rubber having a Mooney viscosity [ML _{1 + 4} (100 ° C.)] of 70 to 150, carbon black, plasticizer,
A rubber molded product obtained by molding a rubber composition to which a crosslinking agent, a crosslinking aid and the like are appropriately added is particularly preferable.

Examples of the vulcanizing adhesive for forming the vulcanizing adhesive layer 6 include a phenolic adhesive, a silicone adhesive, and a chlorinated polymer adhesive.
Preferably, a phenolic adhesive or a silicone adhesive is used. As the phenolic adhesive, specifically, a composition comprising a novolak type phenol resin or a combination of a plurality of resole type phenol resins or a curing agent such as hexamethylenetetramine is dissolved in a solvent such as methanol. An adhesive is preferably used. As the silicone-based adhesive, specifically, an adhesive obtained by reacting a silane coupling agent to form an oligomer and having an amino group or a vinyl group as a functional group is suitably used. When the hydrogenated nitrile rubber mentioned as a particularly preferable rubber composition is used, a phenol-based adhesive and a silicone-based adhesive which are particularly excellent in adhesiveness are preferably used. The vulcanized adhesive layer 6 has a substantially uniform thickness D2.
And the thickness D2 is preferably 2 to 40 μm, and more preferably 5 to 20 μm.

FIG. 2 shows the oil seal member 1 shown in FIG.
5 is a simplified flowchart showing a method for suitably manufacturing the. The oil seal member 1 includes an oil seal member fitting 2 manufactured through the step A, a structure 7 including the phosphate film 4 and the vulcanized adhesive layer 6, and an oil seal member manufactured through the step B. It is manufactured by vulcanizing and bonding with a rubber preform.

The step A includes a metal fitting manufacturing step 11, a surface processing step 12, and an adhesive processing step 13. In the metal fitting manufacturing step 11, first, the metal material described above is appropriately processed to manufacture the metal fitting 5 having a shape and a size according to the purpose. In the subsequent surface treatment step 12, the surface 5a
More specifically, a part of the surface 5a of the metal fitting 5 to which the rubber preform for the oil seal member is to be adhered when the oil seal member is to be formed later is subjected to a chemical conversion coating treatment to form the phosphate film 4 thereon. Form. Such fitting manufacturing process 11
Through the surface treatment step 12, the metal seal 2 for an oil seal member of the present invention is manufactured. In the subsequent bonding step 13, a vulcanized adhesive is applied to the phosphate film 4 of the metal fitting 2 for the oil seal member, dried and baked. The bonding step 13 is performed by using a device commonly used in the art, such as a dipping bath or a spray. Thereby, the vulcanized adhesive layer 6 is formed in a semi-cured state. Through such an A step, a structure 7 including the oil seal member fitting 2, the phosphate film 4, and the vulcanized adhesive layer 6 is produced.

The B step includes a mixing step 14 and a preforming step 15. In the mixing step 14, a rubber composition is prepared. The preparation is carried out by kneading the components of the rubber composition using a kneader such as an intermix, a kneader, a Banbury mixer or an open roll. In the subsequent preforming step 15, the rubber composition prepared as described above is preformed into a shape close to a rubber molded product. For the preforming, an apparatus such as an extruder, an open roll, or a preformer is preferably used as generally performed in the art. The shape and size of the rubber preform are appropriately selected according to the purpose. Through such a B step, an unvulcanized rubber preform for an oil seal member is produced.

Either of the steps A and B may be performed first, or they may be performed simultaneously.

In the vulcanization bonding step 16, the constituent body 7 produced through the step A and the rubber preform produced through the step B are vulcanized and bonded via the vulcanized adhesive layer 6. At the same time, the rubber preform is molded into a rubber molded product 3 for an oil seal member, and the oil seal member 1 is manufactured. Vulcanization is performed using an injection molding machine, compression molding machine, vulcanizing press, etc.
It is performed by heating at 50 to 200 ° C. for about 2 to 30 minutes.

The finishing 18 may be performed as it is via the vulcanizing and bonding step 16, but the secondary vulcanizing step 17 is preferably performed before the finishing 18. The secondary vulcanization is performed by heating at 120 to 170 ° C. for about 1 to 24 hours using an oven or the like. Since the oil seal member obtained through the secondary vulcanization step 17 is more improved in blister resistance than the oil seal member obtained without the secondary vulcanization step 17, It is preferable to go through the secondary vulcanization step 17.

Although the oil seal member 1 of the present invention is suitably manufactured by the manufacturing method including the above-described steps, the manufacturing method of the oil seal member 1 is not limited to the above method, but may be manufactured by a manufacturing method other than the above. May be used.

The metal seal 2 for the oil seal member of the present invention and the oil seal member 1 using the same can be used for various types of chlorofluorocarbon-based refrigerants used as refrigerants in cooling devices and air conditioners, for example, HFC32 (CH ₂ F ₂ ). , HFC125
(CHF ₂ CF ₃ ), HFC143a (C ₂ H ₃ F ₃ ), H
FC134a (hydrofluorocarbon, CH ₂ FC
Excellent resistance to fluorohydrocarbons such as F ₃ ) and mixtures thereof, and also mixtures with refrigeration oils such as mineral oils, polyalkylene glycols and esters, which are usually used in combination therewith, for example, mineral oils, polyalkylene glycols and esters. .

Further, the film 4 has excellent fluorohydrocarbon resistance even in an environment of 150 ° C., and can maintain a stable adhesive property at the adhesive interface with the vulcanized adhesive layer 6. The oil seal member 1 having such a coating 4 is particularly suitable as an oil seal member used for a shaft of an air conditioner for a vehicle such as an automobile or a refrigerator, and its shape and structure are not particularly limited. Not done.

Although the oil seal member of the present invention is particularly preferably used for an air conditioner machine or a refrigerator having a severe use environment as described above, its use is not limited to these, and the oil seal member other than the above may be used. It can also be used suitably for members.

[0027]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to the following examples. (Example 1) A chemical conversion coating treatment was applied to the surface of a metal fitting obtained by metal pressing a cold-rolled steel sheet having a thickness of 0.8 mm to form a zinc phosphate-based coating having a uniform thickness. The zinc phosphate coating had an average thickness of 2.8 μm, and the crystals used were needle-shaped crystals having a maximum size of 20 μm as measured by observation using an electron microscope. After applying a phenolic resin-based adhesive to the film and baking to form a vulcanized adhesive layer, a preformed product of an unvulcanized hydrogenated nitrile rubber composition is brought into contact with the vulcanized adhesive layer, and vulcanized. Heating was carried out at 185 ° C. for 6 minutes in a sulfur press to effect molding and vulcanization bonding, and an oil seal member was prepared as a sample of a lip seal. The hydrogenated nitrile rubber composition has a bound acrylonitrile content of 35.
5 parts by weight, 100 parts by weight of a hydrogenated nitrile rubber having an iodine value of 9.2 (mg / 100 mg) and Mooney viscosity [ML _{1 + 4} (100 ° C.)] of 136, 55 parts by weight of FEF carbon black, and liquid polybutadiene 5 parts by weight,
A mixture of 5 parts by weight of a plasticizer, 3 parts by weight of an organic peroxide, 2 parts by weight of an antioxidant, and 5 parts by weight of zinc oxide was used.

(Example 2) A zinc-calcium phosphate-based coating consisting of granular crystals having an average thickness of 3.9 µm and a maximum size of 10 µm measured by observation using an electron microscope was formed. In the same manner as in Example 1,
A sample of a lip seal was prepared.

Example 3 A zinc phosphate coating having an average thickness of 3.0 μm and a needle crystal having a maximum size of 50 μm as measured by observation using an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

(Example 4) A zinc phosphate coating having an average thickness of 5.2 µm and a needle crystal having a maximum size of 8 µm as measured by observation using an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

Example 5 A zinc phosphate-based coating consisting of needle-like crystals having an average thickness of 6.0 μm and a maximum size of 15 μm as measured by observation using an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

Example 6 A zinc-calcium phosphate-based coating consisting of granular crystals having an average thickness of 5.2 μm and a maximum size of 5 μm as measured by observation using an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

(Example 7) Except that a zinc-calcium phosphate-based film composed of needle-like crystals having an average thickness of 4.0 µm and a maximum size of 30 µm as measured by observation using an electron microscope was formed. In the same manner as in Example 1,
A sample of a lip seal was prepared.

Comparative Example 1 A zinc phosphate coating having an average thickness of 5.9 μm and a needle crystal having a maximum size of 90 μm as measured by observation with an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

(Comparative Example 2) A zinc phosphate coating having an average thickness of 9.3 µm and a needle crystal having a maximum size of 110 µm as measured by observation using an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

Comparative Example 3 The average thickness was 20 μm,
A sample of a lip seal was prepared in the same manner as in Example 1 except that a zinc calcium phosphate-based coating composed of needle-shaped crystals having a maximum size of 20 μm as measured by observation using an electron microscope was formed. .

Comparative Example 4 The average thickness was 20 μm,
A sample of a lip seal was prepared in the same manner as in Example 1 except that a zinc phosphate-based film made of needle-shaped crystals having a maximum size of 20 μm as measured by observation using an electron microscope was formed.

(Comparative Example 5) A zinc phosphate coating having an average thickness of 0.3 μm and a needle crystal having a maximum size of 20 μm as measured by observation with an electron microscope was formed. A sample of a lip seal was prepared in the same manner as in Example 1.

(Evaluation 1) Each of the test samples obtained in Examples 1 to 7 and Comparative Examples 1 to 5 was subjected to a destruction test using radio pliers, and the state of destruction was observed. The normal properties of the product were evaluated.

(Evaluation 2) Each of the samples obtained in Examples 1 to 7 and Comparative Examples 1 to 5 was subjected to HFC134a at 25 ° C.
After immersion for 24 hours, immediately heated in an oven at 150 ° C. for 1 hour, and then performed a destructive test in the same manner as in the normal evaluation.
By observing the fracture state, the fluorocarbon resistance of each sample was evaluated. Table 1 shows the results of Examples 1 to 7.
Table 2 shows the results of Comparative Examples 1 to 5.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

As described above, according to the present invention, 150
Excellent fluorohydrocarbon resistance even at ℃ environment,
It has become possible to provide an oil seal member provided with a film whose adhesive interface with a vulcanized adhesive layer can maintain stable adhesiveness, and a metal fitting for the oil seal member used therefor.

[Brief description of the drawings]

FIG. 1 is a simplified sectional view showing a preferred example of an oil seal member 1 using an oil seal member 2 of the present invention.

FIG. 2 is a simplified flowchart showing a method for suitably manufacturing the oil seal member 1 shown in FIG.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 oil seal member 2 metal fitting for oil seal member 3 rubber molded product for oil seal member 4 phosphate film 5 metal fitting 6 vulcanized adhesive layer

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-149465 (JP, A) JP-A-1-203763 (JP, A) JP-A-53-53531 (JP, A) (58) Field (Int. Cl. ⁷ , DB name) C23C 22/00-22/86 F16J 15/12

Claims (3)

(57) [Claims] 1. A oil seal member Average thickness consists particle size 80μm or less of the crystal is characterized in that it comprises at least part of its surface a phosphate coating having a uniform one thickness of 0.5~10μm Metal fittings. 2. A metal fitting for an oil seal member according to claim 1, which is used for at least one of an oil seal member of a refrigerator and a compressor for a car air conditioner. 3. The oil seal member fitting according to claim 1 or 2 and a rubber molded product for the oil seal member are vulcanized and bonded via a vulcanized adhesive layer in contact with the phosphate film. An oil seal member characterized by the above-mentioned.