JPH0631369B2 - Lubricant for thermoplastic plastics equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricant which can be used for thermoplastics devices without any trouble, and more specifically, a rotating or sliding member formed of a thermoplastics housing or component. The present invention relates to a fluorine-based lubricant that can be suitably used for various devices having a dynamic mechanism.

Conventional technology and its problems With the remarkable progress of science and technology in recent years, various materials for industrial and consumer equipment and devices are rapidly changing from conventional metals and glass to lightweight and inexpensive plastics. ing. In particular, thermoplastics containing a styrene-based component are easy to mass-produce and have good physical properties, so that they are widely used for housings and parts of electric and electronic devices and OA devices. Electronic circuits that do not involve mechanical operation are increasing as operating mechanisms for these various devices, but on the other hand, conventional mechanisms involving mechanical operations such as rotation and sliding are still indispensable. Lubricants are needed.

When conventional mineral oil-based lubricants are used for equipment with these plastic parts, crazing and cracking occur in the plastic parts where oil adheres, resulting in a phenomenon of strength reduction or damage. Has occurred frequently and has become a serious problem in the industry. Such a problem may cause not only a decrease in the service life of the component and an increase in failures, but also a serious risk that the reliability of the entire system is deteriorated.

Of the oils that are often in contact with molded articles made of thermoplastics, those that easily cause stress cracking include lubricating oil for the rotation and sliding mechanisms, grease, and a rust preventive agent for the molding die, Various oils and greases such as anticorrosion protection coats, release agents, etc. can be mentioned. In recent years, as the weight and size of various devices have been reduced, and the operating mechanism has become faster and the noise has been reduced, the chances of lubricants adhering to the housing have increased. The demand for safe oils and greases that do not damage thermoplastics is increasing.

For this reason, products called lubricants that can be safely used for plastics are already on the market, but in the case of products such as mineral oil and synthetic ester lubricants, crazing occurs at a bending strain rate of 0.5% for plastics. Most of them are cracked, and some of them have extremely low strength (in extreme cases, the strength is zero), so that they cannot be used at present.

In consumer electric, electronic equipment and OA equipment, thermoplastic resins containing styrene-based components, especially modified PPO resin housings are predominantly used at present, but this resin is particularly susceptible to oil attack. For,
Equipment manufacturers have reached the point where product design is affected, such as by sticking metal foil to areas where oil may come into contact with them and surpassing the immediate situation.

Means for Solving the Problems In view of the present situation, the present inventors have earnestly studied to develop a lubricant that can be suitably used for a thermoplastics-made device, and as a result, the specific fluorocarbons shown below are obtained. It has been found that polyethers can achieve the intended purpose of the present invention, and the present invention has been completed here.

That is, the present invention provides at least one selected from fluoropolyethers represented by the following formula (1), fluoropolyethers represented by the following formula (2) and fluoropolyethers represented by the following formula (3). The present invention relates to a lubricant for a device made of a thermoplastics.

[In the formula, p, q, and r are each 0 or an integer, and 2
It satisfies ≦ p + q + r ≦ 200. ] [In the formula, the value of n is a real value of 2 ≦ n ≦ 60. ] [Wherein the ratio of n to m is about 40: 1 and the molecular weight is about 4
It is in the range of 00 to 7000. ] The fluoropolyethers represented by the formula (1) include _{F- (CF 2 CF 2 CF 2} O) r -CF 2 CF 3, F-
_{(CH 2 CF 2 CF 2 O} ) can be exemplified p _-CF 2 CF ₃ and the like.

The fluoropolyether represented by the above formula (1) can be prepared, for example, according to the method described in JP-A-60-202122.
It can be synthesized by ring-opening polymerization and fluorination of 2,2,3,3-tetrafluorooxetane. Further, the fluoropolyether represented by the above formula (2) can be obtained, for example, from US Pat.
It can be synthesized by ring-opening polymerization and terminal stabilization of hexafluoropropylene oxide according to the method described in US Pat. No. 2,228,26, US Pat. No. 3,242,218 and the like. Further, the fluoropolyether represented by the above formula (3) can be obtained, for example, from JP-B-45-10929 and JP-A-46-1.
It can be synthesized by copolymerization of hexafluoropropylene and oxygen and terminal stabilization according to the method described in JP 1164, JP 49-45719 and the like.

There are no particular restrictions on the use of the lubricating composition of the present invention, and it can be used in the same manner as conventionally known lubricating compositions.

The thermoplastics to which the lubricant composition of the present invention is applied is not particularly limited, and conventionally known ones can be widely exemplified. For example, modified PPO resin, ABS resin, A
Examples thereof include S resin, ABS / polycarbonate polymer alloy resin, and styrene-modified resins such as styrene-methyl methacrylate resin.

Examples of equipment using these plastics materials include copying machines, printers, floppy drive devices, VTRs, compact discs, optical disc devices, cameras, clocks and the like. The composition of the present invention can be suitably used not only as a lubricant for the moving parts of these devices but also for non-moving parts such as tapping, for any purpose, or in contact with thermoplastic parts. It can also be preferably used as a rust preventive.

Effects of the Invention As is clear from the examples and comparative examples described below, modified PPO
Resin and ABS resin have a bending strain rate of 0.5% and crazing occurs with a commercially available mineral oil, and the elongation retention rate is 35% or less, which is far from the acceptance criteria, whereas the composition of the present invention is used. In addition to 0.5% distortion rate,
%, No crazing or cracking occurred, and the strength retention rate was 80% or more, which is a very good result, and 100%.
Some of them showed close values, and the elongation retention was 50% or more. The difference from the conventional product was clear, and the effect of the present invention was clearly recognized.

Examples The present invention will be further clarified below with reference to Examples and Comparative Examples.

In addition, the tensile strength retention rate and the tensile elongation retention rate in each example are measured by the following methods.

That is, a JIS No. I type test piece prepared by injection molding or cutting from a target thermoplastics is given by the following formula (4) ε _max = Mh / 2EI = 6hδ / L ² (4) [where ε _max is The maximum bending strain on the tensile side of the test piece, M is the bending moment of the test piece, E is the elastic modulus of the material of the test piece,
I is the moment of inertia of area of the test piece, h is the thickness of the test piece, L
Is the distance between the fulcrums of the test piece, and δ is the deflection. ] Bending strains of 0%, 0.5%, and 1% calculated in [1] were added as shown in Fig. 1, and the test oil was adhered (adhered) to the tensile side, and allowed to stand at 20 ° C for 7 days, and tested. After removing the oil agent, a visual inspection and a tensile test were performed, each tensile strength and tensile elongation were measured, each retention rate was calculated, and the percentage of this value was used as a parameter.

In the above, the deflection was applied to the test piece using a stress crack test tool. The test oil agent was adhered to the test piece with absorbent cotton or a brush when it was a liquid material with high viscosity such as oil or grease, and when it was a substance with low viscosity, a filter paper impregnated with the material was adhered to the test piece. . The contact position of the test oil agent is the surface of the test piece where the maximum stress occurs.

The criteria for judgment were that no abnormalities such as crazing and whitening were observed in the visual test, the retention rate of tensile strength was 80% or more on average and the retention rate of tensile elongation was 50% or more, and it was set to pass.

Example 1 A JIS I tensile test piece made of ABS resin [Styrac 191, manufactured by Asahi Kasei] or modified PPO resin [Yupiace AN-45, manufactured by Mitsubishi Gas Chemical Co., Ltd.] was bent by the above formula (4). Strain 0%, 0.5%, 1% is added, p = q = 0 in the above formula (1) on the tensile side, and r is a perfluoro having an average value of about 30 (average molecular weight of about 5000). A filter paper impregnated with a lubricating oil composed of ether was brought into close contact with the filter paper, allowed to stand at 20 ° C. for 7 days, the lubricating oil was removed with Freon 113, and a visual inspection was performed, followed by a tensile test.

As a result of the visual inspection of the test conducted with the number of repetitions of 0%,
No abnormality was observed in any of the bending strains of 0.5% and 1%. The results of tensile strength and elongation measurement of the test piece were good, showing the values shown in Table 1 below.

Example 2 In the above formula (1), p: q: r≈2: 1: 5,
The inspection and testing were performed in the same manner as in Example 1 except that a lubricating oil composed of fluoropolyether having a molecular weight of about 4,500 was used.

As a result of visual inspection, no abnormality was observed in any of 0%, 0.5%, and 1% bending strain. Further, the results of tensile strength and elongation measurement of the test piece showed the values shown in Table 2 below, which were good results.

Example 3 In the above formula (2), n is about 12 (average molecular weight of about 20).
The inspection and test were conducted in the same manner as in Example 1 except that the lubricating oil consisting of perfluoropolyether (00) was used.

As a result of visual inspection, no abnormality was observed in any of 0%, 0.5%, and 1% bending strain. Further, the results of the tensile strength and the elongation measurement of the test piece were good, showing the values shown in the following third surface.

Example 4 An inspection and a test were performed in the same manner as in Example 1 except that a lubricating oil made of fluoropolyether having an average molecular weight of about 3000 was used in the above formula (3).

As a result of visual inspection, no abnormality was observed in any of 0%, 0.5%, and 1% bending strain. The results of tensile strength and elongation measurement of the test piece were good, showing the values shown in Table 4 below.

Comparative Example 1 A JIS I tensile test piece made of an ABS resin [Styrac 191, manufactured by Asahi Kasei] or a modified PPO resin [Yupiace AN-45, manufactured by Mitsubishi Gas Chemical Co., Ltd.] was bent by the formula (2). Strain 0%, 0.5%, 1% was added, and a filter paper impregnated with a lubricant for commercial plastics and a lubricant for commercial plastics (for high temperature) was adhered to the tension side,
After standing at 20 ° C. for 7 days, the lubricating oil was removed with methanol, a visual inspection was performed, and then a tensile test was performed.

0.5% as a result of the visual inspection of the test performed with the number of repetitions 3
Also, crazing or cracking was observed at a bending strain of 1%. Also in the tensile test, the strength was significantly reduced.

Comparative Example 2 Using a commercially available mineral oil-based lubricating oil, an inspection and a test were conducted in the same manner as in Example 1 above.

As a result of visual inspection, the occurrence of crazing was observed at bending strains of 0.5% and 1%. Also in the tensile test, the decrease in elongation was remarkable.

Example 8 (Example of use in copying machine) The lubricating oil used in Example 1 was applied to a portion of a copying machine housing molded using a modified PPO resin, which was particularly susceptible to stress (conventional stress cracks were often generated). Then 2
Tests were conducted at 5 ° C and 65 ° C up to 720 ° C, respectively. As a result of visual inspection, in all cases, no occurrence of stress cracks was observed, and it was confirmed that the product can be used safely.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a drawing for explaining a test method for measuring tensile strength and tensile elongation.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location C10N 40:14 (72) Inventor Shinichi Yamada 463 Kagasuno, Kawauchi Town, Tokushima City, Tokushima Prefecture Otsuka Chemical Co., Ltd. Company Tokushima Factory (72) Inventor Mitsuo Hirohama 10-33 Ashihara-cho, Nishinomiya-shi, Hyogo Matsumura Oil Research Institute Co., Ltd. (72) Inventor Minsei Akada 10-33 Ashihara-cho, Nishinomiya-shi Hyogo Matsumura Co., Ltd. Petroleum Research Institute (56) Reference JP 52-16561 (JP, A) JP 58-215495 (JP, A) JP 62-265394 (JP, A) JP 61-155345 (JP, A) A) JP-A-61-254663 (JP, A) JP-A-62-232497 (JP, A) JP-A-62-101696 (JP, A) European Patent Application Publication 165649 (EP, A)

Claims (4)

[Claims] 1. The following formula (1) [In the formula, p, q, and r are each 0 or a positive integer, and satisfy 2 ≦ p + q + r ≦ 200. ] A fluoropolyether represented by the following formula (2) [In the formula, the value of n is a real value of 2 ≦ n ≦ 60. ] Fluoropolyethers represented by and the following formula (3) [Wherein the ratio of n to m is about 40: 1 and the molecular weight is about 4
It is in the range of 00 to 7000. ] A lubricant for equipment made of thermoplastics comprising at least one selected from fluoropolyethers represented by: 2. A fluoropolyether of the formula (1) is p =
The lubricant according to claim 1, wherein q = 0. 3. A fluoropolyether of formula (1) is q =
The lubricant according to claim 1, wherein r = 0. 4. Thermoplastics are modified PPO, A
The lubricant according to any one of claims 1 to 3, which is at least one selected from the group consisting of BS, AS and HIPS.