JPS5914492B2 - Patsukin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to packing, and more specifically, it provides a packing suitable for use in articles such as showcases, coolers, refrigerators, etc., which have a built-in vibration generating source such as a motor. It is.

Conventional packings include asphalt-impregnated packings (
Glass wool, felt, cloth, leather, etc. are used as the base material.

), but these impregnated packings are highly temperature sensitive because the impregnated substance is asphalt, have poor workability during installation, and have the drawback that a sufficient packing effect cannot be obtained. That is, because asphalt is highly sensitive to temperature, when an impregnated packing is tightened with a nut or the like to the base surface of an article at high temperatures, such as in the summer, softened asphalt flows out and contaminates the surface of the article. On the other hand, in low temperatures like winter, the asphalt solidifies, so the impregnated packing lacks elasticity and flexibility, making it difficult to adhere to the product surface and/or nut surface, and if you try to force it into contact, it will It has the disadvantage of requiring considerable torque pressure. Moreover, the impregnated packing has poor restorability after compression, so it has the disadvantage that it cannot absorb the vibrations of the article and cannot prevent the nut from loosening due to vibrations with the restoring force of the packing.

Recently, as an impregnated packing with good recovery properties after compression, about 30
A double-expanded polyurethane foam impregnated with asphalt has been proposed, but even this foam-impregnated type cannot prevent the asphalt from flowing out when tightening nuts, and its resilience after compression is poor in winter. There are 15 problems in that it is not sufficient at the time when asphalt hardens.

The packing of the present invention includes bolts (including construction bolts such as channel bolts) that are screwed onto electrical appliances, buildings, vehicles, etc.

) screws (including construction screws such as tapping screws), etc., and is characterized by exhibiting properties such as waterproofing, rustproofing, and preventing nuts from loosening. More specifically, the packing of the present invention uses a copolymer consisting of ethylene, α-olefin, and a cyclic or non-cyclic polyene having a non-conjugated double bond as a foam material alone or a rubber mainly composed of the copolymer. and a water-repellent and sticky softening substance and/or resin, a blowing agent, and recycled rubber as essential components, and the mixture is
The foam should be foamed to double its original size, and the foam should have a cell wall structure composed of the rubber and the softening substance and/or resin, and the closed cell structure should be at least 55% (volume ratio), and it should be compressed by 50%. The subsequent recovery rate loss is 30% or less, and the torque pressure at 50% compression is 10k9.? It is characterized by the following: and the swelling ratio at 50% compression is 15% or more, and such functions are difficult to obtain with ordinary impregnated packing.

Furthermore, the packing of the present invention is characterized by excellent chemical resistance (particularly alkali resistance) and weather resistance. To explain this invention more specifically, a copolymer consisting of ethylene, α-olefin and a cyclic or acyclic polyene having a non-conjugated double bond or a rubber mainly composed of the copolymer and a water repellent and adhesive It is a packing made of a plate-shaped foam that is foamed to an expansion ratio of 2 to 7 times by foaming and vulcanizing a mixture whose essential components are a softening substance and/or resin, a foaming agent, and recycled rubber. , the packing has a cell wall structure consisting of the rubber and a softening substance and/or resin having at least 55% (volume ratio) of closed cells, and the following A. The present invention provides a packing characterized by having physical property values of B and C.

A: Restoration rate loss after 50% compression is 30% or less.

B: Torque pressure at 50% compression is 10k9? below. C:
Expansion rate at 50% compression is 15% or more. The mixture that becomes the foam material of the packing of this invention is preferably ethylene, α
- A copolymer consisting of an olefin and a cyclic or acyclic polyene having a non-conjugated double bond alone or a rubber mainly composed of the copolymer and a rubber having water repellency and adhesive properties in excess (by weight) of the rubber. A softening substance and/or resin and known compounding agents such as a blowing agent, a vulcanizing agent, a vulcanization accelerator, a vulcanization accelerating aid, a filler containing recycled rubber, a coloring agent, an anti-aging agent, etc. are combined by a conventional method. As is clear from the blending ratio detailed below, the mixture is in the form of a mousse with appropriate rubber elasticity.

The rubbers used to produce the mixture include:
A copolymer consisting of ethylene, α-olefin, and a cyclic or acyclic copolymer having a nonconjugated double bond (hereinafter referred to as EPDM) is used. However, when compressing and deforming the packing and using it as a waterproof material in areas exposed to weak indirect light (faint sunlight) for a long period of time, EPDM alone or as a rubber material has excellent weather resistance and is resistant to stress cracks due to aging. At least 30% by weight EP in the rubber component
A mixture with a rubber component such as butyl rubber containing DM is suitable, and the effect of resisting stress caused by compressive deformation and suppressing cracks is a property that cannot be obtained with anything other than EPDM. EP
To elaborate on DM, EPDM is a terpolymer consisting of ethylene, propylene or butene-1 and the polyene monomers listed below, including synchropentadiene, 1,5-cyclooctadiene, 1,1- cyclooctadiene, 1,6-
Cyclododecadiene, 1,7-cyclododecadiene, 1
・5,9-cyclododecatriene, 1,4-cycloheptadiene, 1,4-cyclohexadiene, norbornadiene, methylenenorbornene, 2-methylpentadiene-1,4,1,5-hexadiene, 1,6-heptadiene, Examples include methyl-tetrahydroindene and 1,4-hexadiene. The copolymerization ratio of each monomer is preferably 30 to 80 mol% for ethylene and 0.1 to 2 mol% for polyene.
A terpolymer containing 0 mol% and the remainder being α-olefin is used to obtain a terpolymer with a viscosity of ML1+4 (100°C) 40 to 90.
This is preferable because it provides the packing with good mechanical strength. The water-repellent and sticky softening substances and/or resins added to the rubbers make the mixture that becomes the foaming material of the packing viscous (molecular weight ML).
It functions to adjust the temperature to a soft paste with a temperature of l+4 (100°C) 2 to 15, preferably 4 to 10). The film viscosity of the mixture is such that the packing obtained by molding the mixture into a plate shape and foaming and vulcanizing the mixture is moderately flexible and has sufficient recovery properties as a waterproof material after compression deformation. . Softening substances that cause such a predisposition include spindle oil,
Lubricating oils such as machine oil and cylinder oil, process oils such as paraffinic process oils, aromatic process oils, petroleum asphalt process oils, liquid paraffin, paraffin such as vaseline, ozokerite, ceresin, gilsonite, mineral lava, etc. Coal tar such as tarpitz, castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, bean oil, fallen raw oil,
Aliphatic resin oils such as wood wax, waxes such as beeswax, carnauba wax, and lanolin, other polybutenes, liquid polyisobutylene, and the like are preferably used.

As the resin, bituminous materials such as asphalt and asphalt pitch, phenol resin, xylene resin, coumaron resin, petroleum resin, and atactic polypropylene are preferably used. Such softening substances and/or resins are preferably added in an amount of 1 part by weight per 100 parts by weight of rubber.
05 to 350 parts by weight, more preferably 120 to 25 parts by weight
By adding 0 parts by weight, the base material of the foam material of the packing which is the object of this invention is prepared.

If the softening substance and/or resin is less than 105 parts by weight, it will not be possible to obtain a packing having the specific physical properties targeted by the present invention, and moreover, the packing will not contain at least 50% of the packing when used.
Even when compressed, sufficient effects such as waterproofing, rust prevention, and nut loosening prevention cannot be achieved, and if the amount exceeds 350 parts by weight, the resulting packing will be stiff and difficult to absorb, which is undesirable for work. An appropriate amount of the following compounding agent (100 to 500 parts by weight per 100 parts by weight of the rubber) is added to the base material to produce a mixture that becomes a foam material. Specific examples of compounding agents include: (a) Foaming agents such as inorganic agents such as sodium bicarbonate and calcium bicarbonate, N-N/- dinitroso pentamethylene tetramine, N-N'-dimethyl-N −
Nitroso compounds such as N/-dinitroso terephthalmamide, azo compounds such as azodicarbonamide, azobisisobutyronitrile, diazoaminobenzene, and other sulfonyl hydrazides, etc. (b) As a vulcanizing agent,
For example, sulfur, magnesium oxide, zinc white, p-quinone dioxime type, etc. (c) As a vulcanization accelerator, for example, thiuram type such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, other guanidine type, thiazole type, etc. (2) Vulcanization accelerators such as stearic acid and lauric acid; (1) Fillers such as calcium carbonate, clay, talc, asbestos, recycled rubber, shellac, and glass; Fibers, wood flour, fiber waste, etc.
(f) Other coloring agents, anti-aging agents, etc. From viscous mixtures with rubber elasticity made by mixing rubbers with added softening substances and/or resins and compounding agents, for example, mold release agents can be used. Thickness 0.1~ on the sex conveyor
It is usually molded into a plate shape with a temperature of 120 to 200°C, and the foaming ratio is 2 to 7 times, preferably 3 to 4 times.
Heat foam vulcanization for ~60 minutes to produce a foam tissue structure with at least 55%, preferably at least 65% closed cells by volume, and 50% compression (conditions: 72 hours of compression time, one irradiation with a standard weather meter, sample shape , outer diameter 22~X
Inner diameter 5.5 ~ x thickness 5.8♂) for 24 hours (20℃ x
65%) The recovery rate loss after standing is 30% or less, preferably 14% or less, and when compressed by 50% (conditions: 20℃ x 65%R
．． H. Compression speed 10~/Sec. Sample shape Outer diameter 2
．． 2~ x inner diameter 5.5~ x thickness 5.8~) torque pressure is 1
0k9・? Below, preferably 8 kg・? Below, 50%
Expansion ratio during compression (measurement conditions are based on torque pressure) is 15
A packing material having physical properties of at least 20%, preferably at least 20%, is produced.

In addition, the recovery rate loss was calculated|required by the following formula.

A: Original thickness of sample B: 20'C, X65%R. after decompression. H. X Sample thickness after 24 hours.

In addition, the bulge rate refers to the above-mentioned packing material, for example, an outer diameter of 5 to 5.
100', refers to the degree of expansion of the packing toward the center hole when compressive deformation is applied to a donut-shaped packing with a center hole with an inner diameter of 2 to 50 mm under the conditions described above. The swelling ratio was calculated using the following formula.

A1: Original pore diameter of sample B1: Pore diameter of sample after 50% compression This invention will be specifically explained using the drawings.

Figures 1 and 2 show examples of the shape of this invention.
In this example, the packing 1 has a generally known donut shape and has a central hole 2. Figure 3~
FIG. 6 is a schematic diagram showing an example of use of the packing 1 according to the present invention.

FIG. 3 illustrates the overlapping joint of the outer wall panels H1 and H2 of a large cooler. Y in the figure is a screw. Fourth
The figure shows an example of use in a curtain wall joint, in which the seal 1 is pressed and fixed by a joint cover Z. FIG. 5 shows an example of the use of corrugated plates H3 and H4 made of plastic, metal, etc. in an overlapping joint, which is fixed with a channel bolt Y1.
FIG. 6 shows an example of its use in a V-corrugated plate attachment part of a roof, in which the packing 1 is interposed between the corrugated plates H3 and H4, and is held in place by bolts Y2. Figure 7 shows the flange parts H5 and H of the refrigerator panel by cutting the above-mentioned packing material into tape shapes.
6 shows an example of how the packing 17 is used when it is clamped along the length direction of the flange portion of the packing 17.

The gasket of this invention has a cell wall structure composed of rubber, a softening substance, and/or a resin, so it has excellent adhesion and flexibility. By tightening with torque pressure, the cell walls come into close contact with each other and exhibit good waterproof properties.

Moreover, since the width of the compression range is wide and the expansion ratio at 50% compression is high, the packing adheres tightly around the bolt by moderate compression, and good waterproof properties can be obtained. In addition, the recovery rate loss after 50% compression is small, that is, the recovery performance is excellent, so
The nut (via the washer) is constantly pressed by the restoring force of the packing, so even if the fitting to which the packing is attached has a built-in motor that is a source of vibration, such as a cooler, the nut will not loosen. There is no such thing. Examples of this invention will be shown below. The words "part of the text" indicate parts by weight. Example 1 Blend Composition The above blend was mixed in a Banbury mixer (at 80°C
±2 minutes), then masticate with a mixing roll (60
℃±10℃ for 7±2 minutes) to obtain a viscosity of M
A viscous mixture of L1+4 (100 DEG C.) 17-25 is obtained.

Next, the mixture was formed into a sheet (4 to 55 mm) using a rubber extruder.
0~x600~) and heat it in a heating furnace (170℃)
for 60 minutes to vulcanize and foam, then reduce to 6% x 810 x 75O
A plate-shaped packing material was obtained.

The foaming ratio of this material is approximately 3 times, and the closed cell ratio is 6 times the total volume.
It was 6%.

Next, this material is shaped as shown in Figure 1 with an inner diameter of 5.5~.
A donut plate-shaped packing for punching tests with an outer diameter of 22 mm or more was obtained. Its physical properties and characteristics are shown in Table 1.

Examples 2 to 4 The manufacturing method of the packing is based on Example 1.

In Comparative Example 3, a polyurethane foam of approximately 30 times the size was impregnated with a mixture of 100 parts of asphalt, 20 parts of petroleum resin, and 100 parts of kerosene at a rate of 0.27 per 1 d.

As is clear from the above examples, the seal of the present invention does not cause any softening material and/or resin to flow out even when the seal is tightened with a nut, and has low temperature sensitivity, so the seal effect and installation work depend on the working temperature conditions. It has the remarkable effect of not being affected by gender.

Moreover, the low torque pressure makes it easy to install the gasket without damaging the base surface of the product, and the high bulge ratio provides excellent waterproofing around the bolt, and the low loss of restoring rate allows for vibration of the product. It has the special effect of absorbing water over a long period of time and effectively preventing nuts from loosening.

[Brief explanation of drawings]

Figure 1 is a perspective view showing an actual example of the packing of this invention, Figure 2
The figure is a cross-sectional view of FIG. 1 taken along the line I-' and viewed from the direction of the arrow, and FIGS. 3 to 7 are schematic diagrams showing examples of the use of the packing of the present invention. 1...Packing, 2...Center hole, Y,
Yl, Y2...Bolt.

Claims (1)

[Claims] 1. A copolymer consisting of ethylene, an α-olefin, and a cyclic or non-cyclic polyene having a non-conjugated double bond, or a rubber containing at least 30% by weight of the copolymer, and water repellency and adhesive properties. A packing made of a plate-shaped foam foamed to an expansion ratio of 2 to 7 times by foaming and vulcanizing a mixture containing a certain softening substance and/or resin, a foaming agent, and recycled rubber as essential components, The packing shall have a cell wall structure consisting of the rubber and a softening substance and/or resin having at least 55% (volume ratio) of closed cells, and have the following physical property values A, B and C. Packing featuring: A: Restoration loss after 50% compression is 30% or less. B: Torque pressure at 50% compression is 10 kg/cm or less. C
: Expansion rate at 50% compression is 15% or more.