JP2014020449A - Liquid composition for vibration control device and liquid encapsulation type vibration control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of cavitation in an encapsulated working liquid and prevent the occurrence of allophone or impact with the breakdown of the cavitation, in a liquid encapsulation type vibration control device.SOLUTION: A liquid composition for a vibration control device has a solidification point or a fluid point being -20°C or less, and includes: a liquid A containing a liquid A1, for example, comprising ethylene glycol; at least one kind of liquid B having a steam pressure lower than the liquid A and a lot of oxygen dissolving amounts, and for example, comprising fluid paraffin; and a particulate additive subjected to surface treatment by, for example, a fluorine compound or a silicone compound, and having a surface with water repellent property and oil repellent property.

Description

  The present invention relates to a liquid composition for a vibration isolator and a liquid-filled vibration isolator.

  A vehicle such as an automobile is generally equipped with a liquid-filled vibration isolator in which a main liquid chamber and a sub liquid chamber communicate with each other through an orifice. In the liquid-filled vibration isolator having such a structure, cavitation occurs in the liquid sealed in the liquid chamber when vibration is input. For this reason, as a method for preventing the occurrence of such cavitation, for example, in Patent Document 1, a liquid enclosure chamber and an air chamber partitioned by a diaphragm are provided, and the internal pressure of the liquid enclosed in the liquid enclosure chamber is increased. A liquid-filled anti-vibration mount having a possible structure is described. Patent Document 2 describes a vibration isolator in which a pressure absorber is mixed with a liquid in a main liquid chamber, a sub liquid chamber, and an orifice. Patent Documents 3 to 6 describe a vibration isolator that adds a liquid that is incompatible with the main component liquid and has a higher vapor pressure than the main component liquid as the second liquid.

Japanese Patent Laid-Open No. 08-170683 JP 2008-095719 A JP 2010-286026 A JP 2010-286027 A JP 2010-286028 A JP 2010-286035 A

  By the way, for example, as described in Patent Document 3, when a second liquid having a higher vapor pressure than the main component liquid is added, the main component liquid and the second liquid exist separately. For this reason, when the liquid-filled vibration isolator is exposed to a high temperature in the engine room, the internal pressure of the liquid chamber increases due to the generation of the vapor of the second liquid, and the diaphragm and the like are expanded. As a result, there is a problem that the performance of attenuating the input vibration, which is the original function of the liquid filled type vibration damping device, is reduced.

  An object of the present invention is to prevent the occurrence of cavitation in a sealed liquid in the liquid-filled vibration isolator, and to prevent the generation of abnormal noise and impact associated with the collapse of cavitation. Furthermore, even when the liquid-filled vibration isolator is held at a high temperature, it is intended to suppress the expansion of the diaphragm due to the generation of the gas phase and the resulting decrease in the damping performance.

That is, according to the present invention, for a vibration isolator comprising a liquid A having a freezing point or a pour point of −20 ° C. or less and a particulate additive having a water and oil repellent surface. A liquid composition is provided.
Here, the liquid A preferably contains a liquid A1 composed of at least one compound represented by the following general formula (1).

(In general formula (1), R ¹ , R ² , R ³ , and R ⁴ are hydrogen or a methyl group. N is 0 or 1.)
Moreover, it is preferable that the liquid A1 is contained in at least 30 parts by mass in 100 parts by mass of the liquid A1.
Furthermore, it is preferable that the particulate additive has a surface made of a fluorine compound and / or a silicone compound.
The content of the particulate additive is preferably 0.1 parts by mass to 5 parts by mass with respect to the liquid A.
It is preferable that the average particle diameter of the particulate additive is 0.1 μm to 1000 μm.
It is preferable that the particulate additive consists of polymer particles.
The polymer particles are preferably crosslinked polymer particles made of at least one selected from acrylic acid monomers, methacrylic monomers, and styrene monomers.

Next, according to the present invention, the liquid A having a freezing point or a pour point of −20 ° C. or lower, and incompatible with the liquid A, the vapor pressure is lower than that of the liquid A and the amount of dissolved oxygen is at least There is provided a liquid composition for an anti-vibration device comprising one type of liquid B and a particulate additive having a water-repellent and oil-repellent surface.
Here, the liquid A preferably contains a liquid A1 composed of at least one compound represented by the following general formula (1).

(In general formula (1), R ¹ , R ² , R ³ , and R ⁴ are hydrogen or a methyl group. N is 0 or 1.)
The liquid A1 is preferably included at least 30 parts by mass when the total weight of the liquid A and the liquid B is 100 parts by mass.
Furthermore, the liquid B is preferably included in a range of 0.2 parts by mass to 49 parts by mass when the total weight of the liquid A and the liquid B is 100 parts by mass.
The particulate additive preferably has a surface made of a fluorine compound and / or a silicone compound.
The content of the particulate additive is preferably in the range of 0.1 parts by mass to 5 parts by mass when the total amount of the liquid A and the liquid B is 100 parts by mass.
It is preferable that the average particle diameter of the particulate additive is 0.1 μm to 1000 μm.
It is preferable that the particulate additive consists of polymer particles.
The polymer particles are preferably crosslinked polymer particles made of at least one selected from acrylic acid monomers, methacrylic monomers, and styrene monomers.

  Furthermore, according to the present invention, there is provided a liquid-filled vibration isolator provided between the vibration source and the non-vibration source, the first attachment member attached to the vibration source side and the first attachment member attached to the non-vibration source side. 2 mounting members, an elastic member that elastically connects the first mounting member and the second mounting member, a main liquid chamber in which hydraulic fluid is sealed with the elastic member as a part of a wall, and the main A liquid chamber and a sub liquid chamber that is communicated by an orifice passage through a partition member and at least a part of the wall portion is formed of a diaphragm, and is enclosed in each of the main liquid chamber and the sub liquid chamber A liquid-filled vibration isolator is provided, wherein the hydraulic fluid is composed of a liquid composition containing the liquid A and the particulate additive, or a liquid composition containing the liquid A, the liquid B and the particulate additive. .

According to the present invention, in the liquid filled type vibration isolator, cavitation in the enclosed liquid is made fine (that is, the occurrence of large cavitation is suppressed), thereby preventing the generation of abnormal noise and impact due to the collapse of cavitation. To do.
In addition, according to the present invention, even when the liquid-filled vibration isolator is held at a high temperature, the expansion of the diaphragm due to the generation of the gas phase and the resulting decrease in the damping performance are suppressed.

It is a figure explaining the liquid seal mount which is one form of a liquid enclosure type vibration isolator.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary. That is, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are not intended to limit the scope of the present invention, but are merely illustrative examples, unless otherwise specified. . The drawings used are examples for explaining the present embodiment and do not represent actual sizes. The size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation.

<Liquid filled vibration isolator>
FIG. 1 is a view for explaining a liquid seal mount 1 which is an embodiment of a liquid-filled vibration isolator. The liquid seal mount 1 includes a first mounting member 11, a second mounting member 12, an elastic member 13 that connects the first mounting member 11 and the second mounting member 12 and is provided integrally therewith. ing. Further, the second mounting member 12 has a diaphragm 15 attached so as to face the elastic member 13, and is a liquid chamber (a main liquid chamber 16, a sub-liquid) including a closed space surrounded by the diaphragm 15 and the elastic member 13. A chamber 17) is constructed.
The first attachment member 11 is attached to an engine side bracket 100 on an automobile engine (not shown) side as an example of a driving force engine that is a vibration source. The second attachment member 12 is attached to the vehicle body side bracket 200 that is a vibration source.

The first attachment member 11 has a main body portion 112 attached to the vibration source side and a flange portion 113 protruding from the outer edge portion of the main body portion 112. The shape of the main body 112 has an axial shape extending toward the inside of the second attachment member 12 in parallel with the input direction X of the main vibration.
The main body portion 112 of the first attachment member 11 is fitted to one end of the engine side bracket 100 and attached by attachment bolts 111. The other end of the engine side bracket 100 is attached to an automobile engine (not shown) with a bolt or the like.

  The elastic member 13 includes a conical portion 131 formed in a substantially conical shape and a cylindrical tubular portion 132. The inner surface 136 of the conical portion 131 is in close contact with the surface 114 of the main body portion 112 of the first attachment member 11 with an adhesive. The cylindrical portion 132 is formed integrally with the conical portion 131, and its outer surface is in close contact with the surface of the second mounting member 12. The elastic member 13 is made of, for example, a rubber material containing natural rubber.

  The second attachment member 12 has a cylindrical portion 122 that is in close contact with the outer surface of the cylindrical portion 132 of the elastic member 13. In the present embodiment, the first partition member 14 a and the second partition member 14 b provided horizontally are stacked in two upper and lower stages inside the cylindrical portion 122 of the second mounting member 12. An elastic membrane (membrane) 141 is attached to the inside of the upper first partition member 14a. The diaphragm 15 is provided below the second partition member 14b.

  In a liquid sealed chamber formed of a closed space, a working liquid L as a liquid composition for a vibration isolator is sealed. The liquid sealing chamber includes a main liquid chamber 16 defined by the inner surface of the elastic member 13 and the first partition member 14a, and a sub liquid chamber 17 defined by the second partition member 14b and the diaphragm 15. . The main liquid chamber 16 and the sub liquid chamber 17 communicate with each other through an orifice passage 161 formed at the peripheral edge portions of the first partition member 14a and the second partition member 14b. The hydraulic fluid L will be described later.

  In the present embodiment, the vibration in the high frequency region generated from the automobile engine is absorbed by the elastic deformation of the elastic member 13. Further, for example, vibrations in a low frequency region such as an engine shake are damped with a liquid column resonance action of the working fluid L flowing in the orifice passage 161 with a volume change of the main liquid chamber 16 and the sub liquid chamber 17. The internal pressure of the sub liquid chamber 17 is absorbed by elastic deformation of the diaphragm 15. As a result, a pressure difference is generated in the internal pressure between the sub liquid chamber 17 and the main liquid chamber 16, and a smooth flow of the working fluid L in the orifice passage 161 is generated.

(Elastic member 13)
In the present embodiment, the rubber material used for the elastic member 13 of the liquid seal mount 1 is appropriately selected from rubbers usually used for automotive engine mount applications, and is not particularly limited. For example, natural rubber (NR), polyisoprene rubber (IR), high cis-polybutadiene rubber (HCBR), low cis-polybutadiene rubber (LCBR), styrene-butadiene copolymer rubber (SBR (emulsion polymerization SBR (random), solution) Polymerized SBR (random, styrene tapered)), etc. Further, acrylonitrile-butadiene copolymer rubber (NBR), hydrogenated acrylonitrile-butadiene copolymer rubber (HNBR), ethylene-α-olefin copolymer rubber (EPR, EPDM) and chloroprene rubber.

Among these, natural rubber (NR) is preferable because it exhibits a low dynamic ratio compared to other rubbers. Further, chloroprene rubber is preferable because weather resistance tends to be improved when used under high temperature as compared with natural rubber (NR) and the like. Here, the dynamic magnification is a ratio (Kd / Ks) between a static spring constant (Ks (unit: N / mm)) measured according to JIS K 6394 and a dynamic spring constant (Kd (unit: N / mm)). ).
The elastic member 13 in the present embodiment prepares a rubber composition in which various reinforcing agents, vulcanizing agents, vulcanization accelerators, plasticizers, anti-aging agents, and the like are blended with the rubber material described above, and vulcanizes the rubber composition. It is formed by.
Next, the working fluid L as a liquid composition for a vibration isolator enclosed in the liquid seal mount 1 will be described.

<Liquid composition I for vibration isolator>
In the present invention, as a first embodiment, a liquid composition I for a vibration isolator (hereinafter sometimes simply referred to as “liquid composition I”) contains two components of liquid A and a particulate additive. To do. Hereinafter, the liquid A and the particulate additive will be described.

(Liquid A)
In the present embodiment, the liquid A which is the first component of the liquid composition I is a liquid having a freezing point or a pour point of −20 ° C. or lower. Furthermore, the liquid A of the liquid composition I contains a liquid A1 composed of at least one compound represented by the following general formula (1).

In general formula (1), R ¹ , R ² , R ³ , and R ⁴ are hydrogen or a methyl group. n is 0 or 1.

  Specific examples of the compound represented by the general formula (1) contained in the liquid A include, for example, ethylene glycol, propylene glycol, 2-methyl-2,4-pentanediol, and 2,4-dimethyl-2,4-pentane. Diol, 1-methyl-1,3-butanediol, 1,3-dimethyl-1,3-butanediol, 1-methyl-1,3-propanediol, 1,3-dimethyl-1,3-propanediol, etc. Is mentioned. Among these, ethylene glycol, propylene glycol, and 2-methyl-2,4-pentanediol are preferable. In the present embodiment, the compound represented by the general formula (1) can be used alone or in combination of two or more compounds.

  In the present embodiment, the liquid A1 is preferably included in at least 30 parts by mass in 100 parts by mass of the liquid A that is the first component of the liquid composition I. Furthermore, the liquid A1 is more preferably contained at least 40 parts by mass in 100 parts by mass of the liquid A. If the content of the liquid A1 contained in the liquid A is excessively small, the liquid A tends to easily penetrate or be absorbed into the elastic member 13 in the liquid seal mount 1 shown in FIG. In that case, the composition of the liquid composition I changes with long-term use. For this reason, the physical properties of the elastic member 13 may change, leading to deterioration of fatigue durability and vibration absorption performance.

(Particulate additive)
The particulate additive having a water repellent and oil repellent surface used in the present embodiment is preferably a particle having an average particle diameter in the range of about 0.1 μm to 1000 μm, preferably about 10 μm to 500 μm.
Further, the water- and oil-repellent surfaces of such particles are formed, for example, when the particles are polymer particles using a fluorine atom-containing monomer as a raw material. Alternatively, it is preferably formed by treating the surface of various particles with a fluorine atom-containing compound, a silicone compound, or the like.
Examples of the fluorine compound used for the surface treatment include fluorine atom-containing oligomers and / or polymers. Examples of the silicone compound include various silicone oligomers and / or polymers, various alkoxysilane compounds, and the like.

In the present embodiment, the particulate additive is preferably made of polymer particles. Specific examples of the polymer particles include, for example, crosslinked polymer particles made from at least one selected from acrylic acid monomers, methacrylic monomers, styrene monomers, olefin monomers, diene monomers, and the like. Further, fluorine-containing acrylic monomers, fluorine-containing methacrylic monomers, fluorine-containing styrene monomers, fluorine-containing olefin monomers, fluorine-containing diene monomers and the like, each containing a fluorine atom, can also be used.
In addition, in order to make the above-mentioned polymer particles into crosslinkable polymer particles, a reactive monomer having at least two functionalities can be used. Examples of the reactive monomer having at least two functionalities include divinylbenzene, polyfunctional acrylate, and polyfunctional methacrylate. Moreover, the method of bridge | crosslinking by irradiating an electron beam etc. to a polymer particle can also be used.

  Specific examples of the particulate additive used in the present embodiment include, for example, polymethylmethacrylate (PMMA) crosslinked particles and surface-treated with acrylic polymer- (b) -fluorinated acrylic polymer; And those treated with an acrylic polymer- (b) -silicone-containing polymer.

  In this Embodiment, content of a particulate additive is 0.1 mass part-5 mass parts with respect to the liquid A, Preferably, it adds in 0.2 mass parts-3 mass parts. When the content of the particulate additive is excessively small, the effect of suppressing abnormal noise accompanying cavitation collapse tends to be insufficient. When the content of the particulate additive is excessively large, the fluidity of the liquid composition I becomes insufficient, so that the vibration-proof performance of the liquid-filled vibration-proof device tends to be insufficient.

(Operation of Liquid Composition I for Vibration Isolator)
As described above, in the present embodiment, a two-component system ((i) liquid A having a freezing point or a pour point of −20 ° C. or lower, (ii) particulate addition that is a particle having a water-repellent and oil-repellent surface. By using the liquid composition I of the agent as the working liquid L sealed in the liquid seal mount 1, the cavitation bubbles are reduced in diameter, and an abnormal sound (transmitted sound) generated when the cavitation bubbles disappear is suppressed. The action mechanism in which such abnormal noise (transmitted sound) is suppressed is considered as follows.

  That is, when the pressure in the liquid chamber of the liquid seal mount 1 is lowered, the particulate additive dispersed in the liquid A serves as a bubble generation nucleus, and cavitation bubbles are generated on the surface thereof. Since cavitation occurs on the surface of the additive C present in large numbers in the liquid A as particles, large bubbles (cavitation) as in the case of only the liquid A component do not occur. Therefore, abnormal noise due to impact when cavitation collapses is also suppressed to a low level.

<Liquid composition II for vibration isolator>
In the present invention, as the second embodiment, the liquid composition II for an anti-vibration device (hereinafter sometimes simply referred to as “liquid composition II”) includes the liquid A, the liquid B, and the particulate additive. It contains three components. Hereinafter, each component will be described.

(Liquid A)
Examples of the liquid A that is the first component of the liquid composition II include the same liquid A as the first component of the liquid composition II described above.

(Liquid B)
The liquid B that is the second component of the liquid composition II is incompatible with the liquid A that is the first component of the liquid composition II, and has a lower vapor pressure and a larger amount of dissolved oxygen than the liquid A. is there.
In the liquid composition II, when the liquid B, which is incompatible with the liquid A, flows in the liquid chamber of the liquid seal mount 1, the liquid B is dispersed as small oil droplets in the liquid A. Liquid B, which has a lower vapor pressure and a larger amount of dissolved oxygen than Liquid A, contains particulate additive particles having water- and oil-repellent surfaces localized at the phase separation interface between Liquid A and Liquid B. An oxygen phase (air phase) is formed as a nucleus, and a large number of fine bubbles are formed.

Here, the vapor pressure of the liquid B needs to be lower than the vapor pressure of the liquid A, and the numerical range thereof is not particularly limited. However, in the present embodiment, it is usually 9 Pa or less at 20 ° C.
Further, the amount of dissolved oxygen in the liquid B needs to be larger than the amount of dissolved oxygen in the liquid A, and the numerical range is not particularly limited, but is usually 20 mg / L or more in the present embodiment.

  In the three-component liquid composition II, the liquid A1 is preferably contained at least 30 parts by mass when the total weight of the liquid A and the liquid B is 100 parts by mass. Furthermore, it is more preferable that 50 mass parts or more are contained. If the content of the liquid A1 is excessively small, the liquid A tends to penetrate or be absorbed into the elastic member 13 in the liquid seal mount 1 shown in FIG. In that case, the composition of the liquid composition II changes with long-term use. For this reason, the physical properties of the elastic member 13 may change, leading to deterioration of fatigue durability and vibration absorption performance.

  In the three-component liquid composition II, the liquid B is preferably included in the range of 0.2 parts by mass to 49 parts by mass when the total weight of the liquid A and the liquid B is 100 parts by mass. Furthermore, it is more preferable that it is contained in the range of 1 part by mass to 30 parts by mass. When the content of the liquid B is excessively small, there is a tendency that the effect of suppressing abnormal noise accompanying cavitation collapse becomes insufficient. In addition, when the content of the liquid B is excessively large, the liquid A is dispersed in the liquid B, and the expansion of the diaphragm due to the generation of a gas phase when the liquid-filled vibration isolator is held at a high temperature, There is a tendency that the attenuation performance due to.

  Specific examples of the liquid B used in the present embodiment include liquid paraffin, paraffinic oil, naphthenic oil, and silicone oil. Further, a fluorinated solvent having a relatively high boiling point is also used.

(Particulate additive)
Further, the particulate additive which is the third component in the three-component liquid composition II may be the same as the component of the liquid composition I described above.
The content of the particulate additive in the liquid composition II is preferably in the range of 0.1 to 5 parts by mass when the total amount of the liquid A and the liquid B is 100 parts by mass. Furthermore, it is more preferable that it is contained in the range of 0.2 part by mass to 3 parts by mass.
When the content of the particulate additive is excessively small, the effect of suppressing abnormal noise accompanying cavitation collapse tends to be insufficient. When the content of the particulate additive is excessively large, the fluidity of the liquid composition I becomes insufficient, so that the vibration-proof performance of the liquid-filled vibration-proof device tends to be insufficient.

<Action of Liquid Composition II for Vibration Isolator>
As described above, in this embodiment, the three-component system ((i) liquid A having a freezing point or pour point of −20 ° C. or lower, (ii) incompatible with liquid A, and having a vapor pressure higher than that of liquid A. At least one kind of liquid B having a low oxygen content and a large amount of dissolved oxygen, (iii) a particulate additive which is a particle having water- and oil-repellent surfaces) By using it as the liquid L, there is an effect that the cavitation bubbles are reduced in diameter, and abnormal noise (transmitted sound) generated when the cavitation bubbles disappear is suppressed. The action mechanism in which such abnormal noise (transmitted sound) is suppressed is considered as follows.

  That is, when the pressure in the liquid chamber of the liquid seal mount 1 is decreased, the liquid B is dispersed as small oil droplets in the liquid A. At this time, it is considered that the particles of the particulate additive having a water- and oil-repellent surface are likely to be localized at the phase separation interface between the liquid A and the liquid B. Since the liquid B contains a large amount of dissolved oxygen, an oxygen phase (air phase) is formed around the particles of the particulate additive at the phase separation interface between the liquid A and the liquid B to form a large number of fine bubbles. Further, when the pressure in the liquid chamber is reduced, the liquid A component is vaporized using such fine bubbles as nuclei, so that large bubbles (cavitation) as in the case of only the liquid A component are not generated. Therefore, abnormal noise due to impact when cavitation collapses is also suppressed to a low level.

As described above, by using the liquid compositions I and II to which the present embodiment is applied as the working liquid L sealed in the liquid seal mount 1, the abnormal noise caused by the occurrence of cavitation is suppressed. Can do.
In the case of the ternary liquid composition II, when the liquid B having a larger amount of dissolved oxygen than the liquid A is used, a large number of particles of the particulate additive are used as nuclei at the phase separation interface between the liquid A and the liquid B. Even when kept at a high temperature, a gas phase is not generated, and a decrease in the damping performance of the vibration isolator is small. Furthermore, as described in Patent Documents 3 to 6, there is little decrease in the damping performance as compared with the case where a high vapor pressure liquid incompatible with the main liquid is used for the liquid seal mount 1.

  In addition, the liquid composition for vibration isolator used in the present embodiment is appropriately mixed with various additives, stabilizers, rust preventives, etc., which are usually used in liquid filled vibration isolators such as automobiles. Can do.

  The vibration isolator using the liquid composition for a vibration isolator to which the present embodiment is applied is not limited to the liquid ring mount 1 illustrated in FIG. In other words, a liquid-filled vibration isolator having a liquid sealed chamber surrounded by the elastic member 13 and the diaphragm 15 is preferably used as the working fluid L sealed in the liquid sealed chamber. Examples of the liquid-filled vibration isolator include various types of automobile anti-vibration rubber devices such as engine mounts, body mounts, cab mounts, member mounts, and differential mounts.

  Below, based on an Example, this invention is demonstrated further in detail. In addition, this invention is not limited to an Example. In the examples and comparative examples, all parts and percentages are based on weight unless otherwise specified.

(1) Cavitation noise measurement of the liquid ring mount 1 After the liquid ring mount 1 shown in FIG. 1 is prepared and the working fluid L is sealed in the liquid chamber (main liquid chamber 16, sub liquid chamber 17), the liquid ring mount 1 The vibration (Sin 13 Hz ± 2.0 mm) was input to and the transmission force (cavitation noise) at the time of cavitation collapse at that time was measured (unit: N). The transmission force was measured for 1 to 20 waves of the input vibration, and the maximum value among them was taken as the result. It shows that generation | occurrence | production of unusual noise is suppressed, so that a numerical value is small. In Tables 1 to 5, the results are displayed as indices (transmitting power indices) when the value in Comparative Example 1 described later is set to 100.

(2) Dynamic characteristic test of liquid ring mount 1 Damping property was measured for the liquid ring mount 1 in which the working liquid L was sealed in the liquid chamber (main liquid chamber 16, sub liquid chamber 17) (unit: N · sec / mm). ). An input with an amplitude of ± 1.0 mm and a frequency range of 5 to 30 Hz was given to the liquid seal mount 1 to measure the frequency dependence of the attenuation coefficient, and the peak value was used as an index of attenuation. The larger the value, the better the attenuation.

(3) Preparation of Elastic Member 13 of Liquid Seal Mount 1 The elastic member 13 of the liquid seal mount 1 is prepared by molding a rubber composition having the following composition by an injection molding method and vulcanizing at 165 ° C. for 10 minutes. did.

(Composition composition)
Natural rubber 65 parts Butadiene rubber 35 parts Carbon black GPF 40 parts Zinc oxide 5 parts Stearic acid 1 part Anti-aging agent 3 parts Wax 1 part Sulfur 1.5 parts Vulcanization accelerator (TMTD) 1 part Vulcanization accelerator (CBS) 0.5 part

(4) Swelling of the diaphragm portion The swelling of the diaphragm portion was determined based on the following criteria.
After the liquid seal mount 1 in which the hydraulic fluid L is sealed in the liquid chamber (the main liquid chamber 16 and the sub liquid chamber 17) is left in a gear oven controlled at 100 ° C. for 48 hours, the diaphragm portion is swollen visually. It was confirmed by comparing with what was left still at room temperature. When the swelling was minute and visual judgment could not be made, the liquid seal mount 1 was shaken to confirm whether there was any sound due to the formation of a gas layer in the liquid chamber. As a result of visual confirmation, the diaphragm was not swollen and no sound was generated when it was vibrated, and "X" was assigned when the diaphragm was swollen or vibrated.

(Examples 1 to 3, Comparative Examples 1 to 3)
In the liquid chamber (main liquid chamber 16, sub liquid chamber 17) of the liquid seal mount 1 shown in FIG. 1, the hydraulic fluid L composed of the two-component liquid composition I (liquid A, particulate additive) shown in Table 1 Was measured, and cavitation noise, attenuation, and swelling of the diaphragm were measured. Further, as a comparative example, only the liquid A and particles that are not subjected to the surface treatment with the liquid A are sealed in the liquid chamber (the main liquid chamber 16 and the sub liquid chamber 17) of the liquid seal mount 1, and the same conditions as in the first embodiment. The cavitation noise and the like were measured.
The results are shown in Table 1 together with the components of the liquid composition I used as the hydraulic fluid L.

In Table 1, the breakdown of the particulate additives is as follows.
<Particulate additive>
(Particle 1 * a)
1% by weight of PMMA cross-linked particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)) and acrylic polymer (b) -fluorinated acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) It has been processed.

(Particle 2 * b): Art Pearl SE-90T (Negami Kogyo Co., Ltd.)
1% by weight of crosslinked PMMA particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)) and acrylic polymer- (b) -silicone-containing polymer (Modiper FS710 (manufactured by NOF Corporation)) It has been processed.

(Particle 3 * c):
PMMA cross-linked particles (average particle size 80 μm: Techpolymer MBX-80 (manufactured by Sekisui Plastics Co., Ltd.)) and acrylic polymer- (b) -fluorinated acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) 1 It is processed by weight%.

(Particle 4 (no treatment) * d): Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)
PMMA cross-linked particles not subjected to surface treatment (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)).

  From the results shown in Table 1, when the liquid composition I containing a particulate additive surface-treated with a fluorine compound or a silicone compound was used (Example 1 to Example 3), no particulate additive was contained. It can be seen that the cavitation noise (transmittance index) is small compared to the case (Comparative Examples 1 and 2) and the case of containing a particulate additive having no surface of a fluorine compound or a silicone compound (Comparative Example 3). Moreover, in Examples 1 to 3, no swelling of the diaphragm portion is observed, and it can be seen that the attenuation is maintained at the same level as in Comparative Examples 1 to 3.

(Example 4 to Example 10, Comparative Example 4 to Comparative Example 7)
A liquid composition II to which liquid paraffin ((* 1) Cosmo White P120 (manufactured by Cosmo Oil Lubricants Co., Ltd.) was added as a three-component liquid B was prepared, and cavitation noise was measured in the same manner as in Example 1. The results are shown in Table 2.
Further, in the same manner as in Example 1, the particulate additive (particle 1 * a) was added to PMMA crosslinked particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)), acrylic polymer ((b ) -Fluorine-containing acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) treated with 1% by weight.
Table 3 shows the results of Comparative Examples 4 to 7 using the liquid composition containing only liquid A and liquid B.

From the results shown in Table 2 and Table 3, when the liquid composition II containing the predetermined particulate additive together with the liquid B was used (Examples 4 to 10), the liquid composition containing only the liquid B It can be seen that the cavitation noise (transmittance index) is small compared to the case of using (Comparative Example 4 to Comparative Example 7). In addition, it can be seen that Examples 4 to 10 maintain the same level of attenuation as Comparative Examples 4 to 7. Furthermore, it turns out that the swelling of a diaphragm part does not generate | occur | produce Example 4-10.
In addition, when the liquid composition II containing the liquid B and the particulate additive is used (Examples 4 to 10), the liquid composition I to which the liquid B is not added is used (Examples 1 to 4). It can be seen that the effect of suppressing cavitation noise (transmitting power index) is further improved compared to Example 3). This has shown that a synergistic effect is acquired by mix | blending both the liquid B and a particulate additive.

(Example 11 to Example 17)
Using the three-component liquid composition II shown in Table 4, cavitation noise and the like were measured in the same manner as in Example 1. The results are shown in Table 4. In addition, seven types of liquids were added as the liquid B. Further, in the same manner as in Example 1, the particulate additive (particle 1 * a) was added to PMMA crosslinked particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)), acrylic polymer ((b ) -Fluorine-containing acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) treated with 1% by weight. The results are shown in Table 4.

In Table 4, the breakdown of the liquid B is as follows.
<Liquid B>
(Paraffinic oil * 2): Atmos 22N (manufactured by JX Nippon Mining & Metals)
(Paraffinic oil * 3): Shell Terrace S2V15 (manufactured by Showa Shell Co., Ltd.)
(Naphthenic oil * 4): SMH8 (manufactured by Sankyo Oil Chemical Co., Ltd.)
(Silicone oil * 5): KF-96-20CS (manufactured by Shin-Etsu Silicone Co., Ltd.)
(Silicone oil * 6): KF-96-100CS (manufactured by Shin-Etsu Silicone Co., Ltd.)
(Silicone oil * 7): KF-414 (manufactured by Shin-Etsu Silicone Co., Ltd.)
(Silicone oil * 8): KF-4003 (manufactured by Shin-Etsu Silicone Co., Ltd.)

  From the results shown in Table 4, Examples 11 to 17 in which seven kinds of liquids were added as the predetermined particulate additives and the liquid B satisfying the predetermined conditions are excellent in suppressing cavitation noise (transmitting force) and are attenuated. It can be seen that the property does not deteriorate and the diaphragm portion does not bulge.

(Examples 18 to 20, Comparative Examples 8 to 9)
Using liquid composition II shown in Table 5, cavitation noise and the like were measured in the same manner as in Example 1. The results are shown in Table 5. In addition, liquid paraffin ((* 1) Cosmo White P120 (manufactured by Cosmo Oil Lubricants Co., Ltd.) was added as liquid B.

The breakdown of the additives in Table 5 is as follows.
<Fluorine solvent>
(Fluorine-based solvent * 9): demnum S-65 (manufactured by Daikin Industries, Ltd .: bp 230 ° C.)
(Fluorine-based solvent * 10): Asahiklin AC-6000 (Asahi Glass Co., Ltd .: bp 114 ° C., vapor pressure (25 ° C.) 2600 Pa)

<Particulate additive>
(Particle 1 * a)
1% by weight of PMMA cross-linked particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)) and acrylic polymer (b) -fluorinated acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) It has been processed.

(Particle 2 * b): Art Pearl SE-90T (Negami Kogyo Co., Ltd.)
1% by weight of crosslinked PMMA particles (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)) and acrylic polymer- (b) -silicone-containing polymer (Modiper FS710 (manufactured by NOF Corporation)) It has been processed.

(Particle 3 * c):
PMMA cross-linked particles (average particle size 80 μm: Techpolymer MBX-80 (manufactured by Sekisui Plastics Co., Ltd.)) and acrylic polymer- (b) -fluorinated acrylic polymer (Modiper FT200 (manufactured by NOF Corporation)) 1 It is processed by weight%.

(Particle 4 (no treatment) * d): Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)
PMMA cross-linked particles not subjected to surface treatment (average particle size 110 μm: Art Pearl SE-90T (manufactured by Negami Industrial Co., Ltd.)).

From the results shown in Table 5, a predetermined particulate additive (particles 2 and 3) different from the particulate additive (particle 1) used in Example 5 described above was added, and the others were the same as in Example 5. When the liquid composition II prepared in Example 1 was used (Examples 18 and 19), it was found that an excellent noise suppressing effect was exhibited, and a decrease in attenuation and a swelling of the diaphragm portion did not occur.
In addition, when a low vapor pressure (1 × 10 ⁻⁵ Pa) (fluorinated solvent * 9) was used (Example 20), an excellent noise suppression effect (transmittance index 20) was exhibited, and the diaphragm portion It can be seen that no blistering occurs.

On the other hand, when a liquid composition containing a particulate additive (particle 4) having no surface (not surface-treated) made of a fluorine compound or a silicone compound (Comparative Example 8) is used, the noise suppressing effect ( It can be seen that the transmission power index 72) cannot be obtained.
Moreover, although the particulate additive (particle 1) used in Example 5 was added, a liquid composition in which a fluorine-based solvent (vapor pressure 2600 Pa (25 ° C.)) having a higher vapor pressure than liquid A was added as liquid B. When an object is used (Comparative Example 9), it can be seen that swelling of the diaphragm portion occurs.

DESCRIPTION OF SYMBOLS 1 ... Liquid seal mount, 11 ... 1st attachment member, 12 ... 2nd attachment member, 13 ... Elastic member, 14a ... 1st partition member, 14b ... 2nd partition member, 15 ... Diaphragm, 16 ... Main liquid chamber, 17 DESCRIPTION OF SYMBOLS ... Secondary liquid chamber, 100 ... Engine side bracket, 111 ... Mounting bolt, 112 ... Body part, 113 ... Flange part, 114 ... Surface, 122 ... Cylindrical part, 131 ... Conical part, 132 ... Cylindrical part, 136 ... Inner surface, 141 ... Elastic membrane (membrane) 161 ... Orifice passageway 200 ... Car body side bracket

Claims (18)

A liquid A having a freezing point or a pour point of -20 ° C or lower;
A liquid composition for an anti-vibration device, comprising: a particulate additive having a water- and oil-repellent surface. The said liquid A contains the liquid A1 which consists of at least 1 sort (s) of the compound represented by following General formula (1), The liquid composition for vibration isolator of Claim 1 characterized by the above-mentioned.

(In general formula (1), R ¹ , R ² , R ³ , and R ⁴ are hydrogen or a methyl group. N is 0 or 1.)   The liquid composition for an anti-vibration device according to claim 2, wherein the liquid A1 is contained in at least 30 parts by mass in 100 parts by mass of the liquid A.   The liquid composition for a vibration isolator according to any one of claims 1 to 3, wherein the particulate additive has a surface made of a fluorine compound and / or a silicone compound.   5. The liquid composition for an anti-vibration device according to claim 1, wherein a content of the particulate additive is 0.1 to 5 parts by mass with respect to the liquid A. 6. object.   The liquid composition for a vibration isolator according to any one of claims 1 to 5, wherein an average particle diameter of the particulate additive is 0.1 µm to 1000 µm.   The liquid composition for an anti-vibration device according to any one of claims 1 to 6, wherein the particulate additive comprises polymer particles.   The liquid composition for a vibration isolator according to claim 7, wherein the polymer particles are cross-linked polymer particles made of at least one selected from acrylic acid monomers, methacrylic acid monomers, and styrene monomers. object. A liquid A having a freezing point or a pour point of -20 ° C or lower;
At least one liquid B that is incompatible with the liquid A, has a vapor pressure lower than that of the liquid A, and has a large amount of dissolved oxygen;
A liquid composition for an anti-vibration device, comprising: a particulate additive having a water- and oil-repellent surface. The liquid composition for an anti-vibration device according to claim 9, wherein the liquid A includes a liquid A1 composed of at least one compound represented by the following general formula (1).

(In general formula (1), R ¹ , R ² , R ³ , and R ⁴ are hydrogen or a methyl group. N is 0 or 1.)   The liquid composition for an anti-vibration device according to claim 10, wherein the liquid A1 is included at least 30 parts by mass when the total weight of the liquid A and the liquid B is 100 parts by mass.   The said liquid B is contained in the range of 0.2 mass part-49 mass parts, when the sum total weight of the said liquid A and the said liquid B is 100 mass parts. 2. A liquid composition for a vibration isolator according to item 1.   The liquid composition for a vibration isolator according to any one of claims 9 to 12, wherein the particulate additive has a surface made of a fluorine compound and / or a silicone compound.   The content of the particulate additive is in a range of 0.1 parts by mass to 5 parts by mass when the total amount of the liquid A and the liquid B is 100 parts by weight. 14. The liquid composition for a vibration isolator according to any one of 13 above.   The liquid composition for a vibration isolator according to claim 9, wherein an average particle diameter of the particulate additive is 0.1 μm to 1000 μm.   The liquid composition for a vibration isolator according to any one of claims 9 to 15, wherein the particulate additive comprises polymer particles.   17. The polymer particle according to claim 9, wherein the polymer particle is a crosslinked polymer particle using at least one selected from an acrylic acid monomer, a methacrylic acid monomer, and a styrene monomer as a raw material. Liquid composition for vibration isolator. A liquid-filled vibration isolator provided between the vibration source and the non-vibration source side,
A first attachment member attached to the vibration source side;
A second attachment member attached to the non-vibration source side;
An elastic member for elastically connecting the first mounting member and the second mounting member;
A main liquid chamber in which a working fluid is sealed with the elastic member as a part of the wall;
A secondary liquid chamber communicated by an orifice passage through the main liquid chamber and a partition member, wherein at least a part of the wall portion is formed of a diaphragm;
The liquid-filled type, wherein the hydraulic fluid sealed in each of the main liquid chamber and the sub liquid chamber is the liquid composition for a vibration isolator according to any one of claims 1 to 17. Anti-vibration device.

Images