JP2008230074A - Manufacturing method of rubber-filler composite - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the low heat build-up performance, fatigue resistance and processability of a rubber composition by uniformly and finely dispersing a filler respecting a rubber-filler composite. <P>SOLUTION: A filler slurry containing 5-20 wt.% of a filler such as carbon black and silica is supplied into a dispersion processing chamber (1) in a flow rate of 300-700 m/sec, the filler is thereby crushed and finely dispersed into the slurry, at least either of the filler slurry having been subjected to the dispersion processing and a concentrated natural rubber latex is supplied into a mixing processing chamber (10) in a flow rate of 300-700 m/sec to mix both of them, and the filler is finely dispersed in the rubber polymer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a rubber-filler composite, which is a composite of rubber and filler. More specifically, the present invention relates to a method for producing a rubber-filler composite used as a master batch in which a filler such as carbon black or silica is dispersed in natural rubber.

  A rubber composition used for tires and the like is blended with a filler such as carbon black for the purpose of reinforcement. Conventionally, the filler and the rubber are mixed by a method called dry mixing, in which the filler is added to the rubber in the form of a powder and kneaded. However, there is a limit to uniform and fine dispersion.

  Therefore, in recent years, a rubber-filler composite called a wet masterbatch has been produced by mixing a rubber slurry and a filler slurry in which fillers such as carbon black and silica are pre-dispersed in water. It has been proposed to improve the low heat build-up and wear resistance on rough roads by blending this with a rubber composition (see Patent Documents 1 to 5 below).

  However, in the conventional method for producing a rubber-filler composite, the aggregated filler is not sufficiently pulverized and it is difficult to maximize the performance of the filler.

  For example, in Patent Document 1 below, the filler slurry and the latex are mixed with each other by supplying the filler slurry as a jet flow under high pressure to entrain the latex fluid. It has been proposed to reduce heat generation and wear resistance on rough roads compared to dry mixing. However, this reference only describes that the filler slurry is dispersed using a homogenizer, and does not disclose pulverization (micronization) using a high-speed jet stream. Further, in this document, the flow rate of the filler slurry when mixing the filler slurry and latex is 100 to 800 feet per second, that is, 244 m / second at the maximum, and the speed is insufficient. It is not sufficient to bring out the maximum performance as a filler composite.

  In the following Patent Document 2, a master batch obtained by mixing and solidifying carbon black slurry and rubber latex is used, and bismaleimide is added to a rubber component composed of isoprene rubber and transpolybutadiene so that crack resistance and low resistance are reduced. It is disclosed to improve the exotherm. However, such a measure leads to an increase in cost. Further, this document only discloses a rotor-stator type high shear mixer, a high-pressure homogenizer, and the like as apparatuses used for preparing the filler slurry (paragraph 0040). Paragraph 0063), the speed around the rotor converted from the rotor diameter is at most 13 m / sec. For this reason, the degree of dispersion of carbon black in the rubber-filler composite is insufficient.

  Patent Document 3 below discloses a method for producing a master batch by decomposing an amide bond in natural rubber latex and then mixing the rubber latex and a filler slurry. Also in this case, as a method for preparing the filler slurry, there is only a description equivalent to the above-mentioned Patent Document 2, and therefore the degree of dispersion of the filler in the master batch cannot be said to be sufficient.

  The following Patent Document 4 also discloses a method of producing a rubber-filler composite by mixing rubber latex and filler slurry, but the peripheral speed of the stirrer at the time of mixing both is at most There is only a description of 12 m / sec. Therefore, the speed is insufficient and it is difficult to maximize the performance of the rubber-filler composite.

In Patent Document 5 below, when preparing a masterbatch containing a plurality of fillers, carbon black and silica are dispersed in water using a high shear mixer to prepare a filler slurry, and then the slurry is latex. A method of mixing with is disclosed. However, this document uses a high shear mixer to mix and disperse fillers having different properties without using a surfactant, and generates an ultra-high-speed flow of the filler slurry to crush the filler. It is not disclosed to do. Therefore, even in this document, it is difficult to maximize the performance of the rubber-filler composite.
JP 2000-507892 A JP 2006-152117 A JP 2004-99625 A JP 2004-182994 A JP 2006-219593 A

  The present invention has been made in view of the above points, and maximizes the performance of the rubber-filler composite by uniformly and finely dispersing the filler in the rubber-filler composite as compared with the prior art. It is an object of the present invention to provide a method for producing a rubber-filler composite capable of improving low heat buildup, fatigue resistance and workability when drawn into a rubber composition.

  In the method for producing a rubber-filler composite according to the present invention, a filler slurry containing a filler is supplied to a dispersion treatment chamber at an ultra-high speed flow having a flow rate of 300 m / second or more to finely add the filler into the slurry. A dispersion step of dispersing, and a mixing step of mixing the dispersion-treated filler slurry with concentrated natural rubber latex.

  In the present invention, more preferably, in the mixing step, at least one of the dispersion-treated filler slurry and the concentrated natural rubber latex is supplied to the mixing processing chamber at an ultra high speed flow rate of 300 m / sec or more. It is to mix both.

  In the above configuration, as a more specific aspect, the dispersion processing chamber has a cylindrical shape, and is provided with a supply port for supplying the filler slurry to one end surface in the axial direction and the other end in the axial direction. It is preferable that a discharge port for the filler slurry subjected to the dispersion treatment is provided in the section, and the filler slurry is injected from the supply port into the dispersion treatment chamber at an ultra high speed flow rate of 300 m / sec or more.

  The mixing chamber has a cylindrical shape, and a first supply port for supplying one fluid of the filler slurry and the concentrated natural rubber latex is provided on one end surface in the axial direction, and one end portion in the axial direction. Is provided with a second supply port for supplying the other fluid of the filler slurry and the concentrated natural rubber latex downstream of the first supply port, and further discharges the fluid mixed at the other end in the axial direction. It is preferable that a discharge port is provided and the one fluid is jetted from the first supply port into the mixing treatment chamber at an ultra high speed flow having a flow rate of 300 m / sec or more.

  According to the present invention, prior to mixing with the rubber latex, the filler slurry is effectively pulverized by treating the filler slurry with an ultra high-speed flow equal to or higher than the sound velocity of 300 m / sec or higher. be able to. By mixing the filler slurry thus dispersed with the rubber latex, the filler can be uniformly finely dispersed in the rubber. Therefore, by using the obtained rubber-filler composite in a rubber composition, the performance of the rubber-filler composite is maximized, and the low heat buildup, fatigue resistance and workability of the rubber composition are improved. Can be improved. Further, by using concentrated natural rubber latex as the rubber latex, it is possible to further reduce heat generation by a synergistic effect.

  Further, in the present invention, when the dispersed slurry of the filler and the concentrated natural rubber latex are mixed at an ultra high speed flow rate of 300 m / second or more, the filler is more evenly mixed in the rubber. It can be finely dispersed, and the performance of the rubber-filler composite can be extracted more effectively.

  Hereinafter, matters related to the implementation of the present invention will be described in detail.

  In the present invention, as the filler, various inorganic fillers such as silica, clay and zeolite can be used in addition to carbon black, and these can be used alone or in combination of two or more. Carbon black, silica, or a combination of carbon black and silica is preferable. Examples of the silica include wet silica, dry silica, colloidal silica, and the like.

  The filler slurry is obtained by dispersing the filler in an aqueous solvent such as water. Such filler slurry can be obtained, for example, by adding water to the filler and stirring with a stirrer. The filler content in the filler slurry is preferably 5 to 20% by weight from the viewpoint of the pulverizing effect in the dispersing step and the mixing effect with the rubber latex in the mixing step.

  In the present invention, concentrated natural rubber latex is used as the rubber latex. Concentrated natural rubber latex is a natural rubber field latex collected by tapping from natural rubber wood (usually a rubber concentration (DRC: Dry Rubber Content) of 20 to 35% by weight) and a known concentration such as centrifugation. Concentrated by the method to increase the rubber concentration. The rubber concentration (DRC) of the concentrated natural rubber latex used in the present invention is preferably 50% by weight or more, more preferably 50 to 70% by weight.

  In the method for producing a rubber-filler composite in the present invention, the filler slurry is finely dispersed in the dispersion step. In the fine dispersion treatment, an ultra-high speed flow of a filler slurry having a flow rate of 300 m / second or more is generated, and this is supplied to a dispersion treatment chamber, whereby the filler is pulverized and finely dispersed in the slurry. Conventionally, such high-speed fine dispersion treatment has not been performed at all for rubber-filler composites particularly for tire applications, and such high-speed fine dispersion treatment is practically advantageous for tire performance. It was not thought to be effective. That is, although it has been conventionally required to uniformly disperse the filler in the rubber, it has not been required to achieve such a fine dispersion. The present invention has been found for the first time to give a practically advantageous effect as a rubber-filler composite used for tires and the like by processing at an ultra-high speed that greatly exceeds the conventional level.

  The flow rate of the filler slurry is preferably 300 to 700 m / second, more preferably 450 to 700 m / second. If the lower limit of 300 m / sec is less than this, the effect of fine dispersion is inferior, and the effect of improving the rubber composition, such as low heat buildup, high fatigue resistance, and workability, is insufficient. On the other hand, the higher the flow rate is, the better as the fine dispersion effect is. However, since a flow rate exceeding 700 m / sec is difficult to control with current machines, the upper limit is preferably 700 m / sec or less.

  In the dispersion step, various dispersants such as anion, cation, nonion, and amphoteric type can be added in advance to the filler slurry. Specifically, examples of the dispersant include sodium salt of β-naphthalenesulfonic acid formalin condensate, lauryltrimethylammonium chloride, polyoxyethylene distyrenated phenyl ether, lauryl betaine, and the like, either alone or Two or more types can be used in combination.

  More specifically, in the dispersion step, an ultrahigh pressure pressure energy is applied to the filler slurry using a high pressure generator or the like to generate an ultra high speed flow having a flow rate of 300 m / second or more. For example, an ultra-high pressure energy of 45 MPa to 245 MPa is applied to accelerate to 300 to 700 m / second.

  Then, this ultra high-speed flow is supplied to the dispersion processing chamber, and the filler slurry is finely dispersed by pulverizing and dispersing the filler by the action of collision, cavitation, turbulent flow, etc. in the chamber. More specifically, (A) a method of finely dispersing by cavitation or turbulent flow when the ultrahigh-speed flow is injected into a chamber filled with fluid, and (B) bifurcating the ultrahigh-speed flow into two. (C) A method in which the super-high velocity flow is jetted onto a rigid body such as a sphere and pulverized by the collision. (D) The filler slurry is accelerated by a plurality of nozzles. And a method of generating ultra high-speed flows, jetting these ultra-high-speed flows into a chamber, colliding and crushing them, and the like.

  FIG. 1 shows a preferred embodiment of the dispersion process, and the dispersion treatment chamber (1) has a cylindrical shape. One end face (1a) in the axial direction of the dispersion processing chamber (1) is provided with a supply port (2) for supplying a filler slurry, and the supply port (2) is supplied with the filler slurry in the state of the high-speed flow. Is connected to a high pressure generator (3). The other end (1b) in the axial direction of the dispersion treatment chamber (1) is provided with a discharge port (4) for the filler slurry subjected to the dispersion treatment.

  In the dispersion step, the dispersion treatment chamber (1) is preliminarily filled with a liquid such as water, and the filler slurry is supplied from the supply port (2) at a flow rate of 300 m / second or more at an ultra high speed flow. Inject into. The injected filler slurry is finely dispersed by pulverizing the filler by cavitation or turbulent flow in the dispersion treatment chamber (1). The liquid initially filled in the dispersion treatment chamber (1) is replaced with the filler slurry by jetting the filler slurry, and the dispersion treatment chamber (1) is filled with the filler slurry in a steady state. It is in the state. The filler slurry finely dispersed in this manner is discharged from the discharge port (4) and sent to the next mixing step.

  Next, in the mixing step, it is preferable to mix both of the filler slurry and the concentrated natural rubber latex dispersed as described above by supplying them to the mixing chamber at a flow rate of 300 m / sec or more. Conventionally, the mixing of the filler slurry and the concentrated natural rubber latex has not been carried out at all at a speed equivalent to or higher than the speed of sound, and for the first time according to the present invention, a rubber-filler composite used for tires and the like A practically beneficial effect has been found.

  In the mixing step, the flow rate of at least one of the filler slurry and the concentrated natural rubber latex is preferably 300 to 700 m / sec, more preferably 450 to 700 m / sec.

  It should be noted that either one of the filler slurry and the concentrated natural rubber latex may be an ultra high-speed flow, but more preferably, both are mixed as an ultra-high speed flow. In the mixing step, the same dispersant as in the dispersing step can be added before mixing, and in that case, it may be added to either the filler slurry or the concentrated natural rubber latex.

  More specifically, in the mixing step, an ultrahigh pressure flow energy is applied to the filler slurry or the concentrated natural rubber latex using a high pressure generator or the like to generate an ultra high speed flow having a flow rate of 300 m / sec or more. For example, an ultra-high pressure energy of 45 MPa to 245 MPa is applied to accelerate to 300 to 700 m / second.

  Then, this ultra high-speed flow is supplied to the mixing treatment chamber, and the filler is finely dispersed in the rubber polymer of the concentrated natural rubber latex by the action of collision, cavitation, turbulence, etc. in the chamber. More specifically, (E) the super-high-speed flow is supplied from the downstream side of one of the filler slurry and the concentrated natural rubber latex while the super-high-speed flow is injected into the chamber filled with the fluid. Mixing both by cavitation and turbulent flow to finely disperse the filler, (F) A method in which the filler slurry and concentrated natural rubber latex are injected into the chamber as ultra-high velocity flows and collided to mix, etc. Is mentioned.

  FIG. 2 shows a preferred embodiment of the mixing step, and the mixing chamber (10) has a cylindrical shape. A first supply port (12) for supplying filler slurry is provided at one end surface (10a) in the axial direction of the mixing treatment chamber (10), and the filler slurry is supplied to the first supply port (12). A high-pressure generator (13) that supplies in an ultrahigh-speed flow state is connected. A second supply port (14) for supplying concentrated natural rubber latex is provided on the downstream side of the first supply port (12) at one axial end (10b) of the mixing treatment chamber (10). A rubber latex supply tank (15) for supplying concentrated natural rubber latex is connected to the 2 supply port (14). The other end (10c) in the axial direction of the mixing treatment chamber (10) is provided with a discharge port (16) for discharging the mixed fluid.

  In the mixing step, the filler slurry processed in the dispersion step is sprayed from the first supply port (12) into the mixing processing chamber (10) at an ultra high speed flow rate of 300 m / sec or more. Due to the flow of the injected filler slurry in the mixing processing chamber (10), the concentrated natural rubber latex is sucked from the rubber latex supply tank (15) into the mixing processing chamber (10) through the second supply port (14). It is. Then, the filler slurry and the concentrated natural rubber latex are mixed by cavitation or turbulent flow in the mixing treatment chamber (10) with the ultrafast flow filler slurry, and the filler is finely mixed in the rubber polymer of the concentrated natural rubber latex. Distributed.

  The mixing ratio of the filler slurry and the concentrated natural rubber latex is preferably within a range such that the filler is 20 to 80 parts by weight with respect to 100 parts by weight of the rubber polymer.

  The mixture of the filler slurry and the concentrated natural rubber latex finely dispersed in this manner is discharged from the discharge port (16), and is then subjected to a conventional method, that is, through a solidification and drying process (not shown), A rubber-filler composite is obtained.

  The obtained rubber-filler composite can be used as a master batch when producing a rubber composition for vulcanization. In such a rubber composition, the rubber component may be only added as a rubber-filler composite, but other rubber may be blended with the rubber-filler composite. Examples of other compounding agents include oil, anti-aging agent, zinc white, stearic acid, softener, vulcanizing agent, vulcanization accelerator, and the like, and are not particularly limited.

  The other rubber is not particularly limited, and examples thereof include various rubber polymers such as natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, butyl rubber, halogenated butyl rubber, ethylene propylene rubber, nitrile rubber, and derivatives thereof. Can be mentioned.

  Since the rubber composition containing the rubber-filler composite can maximize the performance of the filler and improve low heat buildup, high fatigue resistance, and workability, the tire The rubber composition can be suitably used for various rubber compositions including a tire rubber composition such as a tread rubber and a sidewall rubber.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

[Examples 1 to 6]
(Production of master batch)
Master batches of Comparative Examples 1 to 5 and Examples 1 to 6 were prepared by the blending and mixing methods shown in Table 1 below. Comparative Example 1 is a dry blend of natural rubber and carbon black, Comparative Example 2 is a mixture of natural rubber latex and carbon black in powder form, Comparative Examples 3-5 and Examples 1-6 are natural rubber latex This is a mixture of carbon black slurry. Each component in the table is as follows.

・ Natural rubber: RSS # 3,
・ Natural rubber field latex: “NR Latex” (rubber concentration DRC = 30% by weight) manufactured by Golden Hope
Concentrated natural rubber latex: “NR Latex” (Rubber Concentration DRC = 60% by weight) manufactured by Resitex Corporation,
Carbon black: Small particle size carbon “# 2300” manufactured by Mitsubishi Chemical Corporation.

Carbon black slurry A: Carbon black (“# 2300” manufactured by Mitsubishi Chemical Corporation) added to water so as to be 10% by weight, and stirred with a stirrer (stirring speed: 50 m / sec).

Carbon black slurry B: Water was added to carbon black (Mitsubishi Chemical Corporation “# 2300”) so as to be 10% by weight, and after stirring with a stirrer (stirring speed: 50 m / sec), FIG. Dispersion treatment was performed in the dispersion treatment chamber shown (inner diameter = about 20 mm, length = about 25 cm, nozzle diameter of supply port (2) = 0.15 mm). The dispersion treatment was performed by spraying the stirred slurry at a flow rate of 244 m / sec (high pressure generator pressure = 30 MPa) into the dispersion treatment chamber, and this dispersion treatment was passed five times.

Carbon black slurry C: The carbon black slurry B was prepared in the same manner except that the flow rate of the slurry was 300 m / second (pressure of the high pressure generator = 45 MPa).

Carbon black slurry D: Carbon black slurry B was prepared in the same manner as the carbon black slurry B except that the slurry flow rate was 450 m / second (pressure of the high pressure generator = 101 MPa).

Carbon black slurry E: The carbon black slurry B was prepared in the same manner except that the flow rate of the slurry was 600 m / second (pressure of the high pressure generator = 180 MPa).

Carbon black slurry F: Carbon black slurry B was prepared in the same manner except that the flow rate of the slurry was 700 m / sec (pressure of the high pressure generator = 245 MPa).

Carbon black slurry G: In carbon black slurry B, 0.3 weight of carbon black with water and a dispersing agent (“Demol NL (Natrium salt of β-naphthalenesulfonic acid formalin condensate: anionic)” manufactured by Kao Corporation) %, And the slurry flow rate was 700 m / second (pressure of the high pressure generator = 245 MPa), and the others were produced in the same manner.

-Mixing step by ultra high-speed flow: Using the mixing treatment chamber shown in FIG. 2 (inner diameter = about 5 mm, length = about 60 cm, nozzle diameter of the first supply port (12) = 0.15 mm), the carbon black Slurries A to G are injected from the first supply port (12) at a flow rate of 700 m / second (pressure of the high pressure generator = 245 MPa) or a flow rate of 450 m / second (pressure of the high pressure generator = 101 MPa) described in Table 1. At the same time, rubber latex was supplied from the second supply port (14).

(Evaluation of master batch)
A rubber composition was prepared using each of the above master batches. The composition of the rubber composition is 1 part by weight of stearic acid (manufactured by NOF Corporation), 1 part by weight of anti-aging agent (“6PPD” manufactured by Monsanto), 150 parts by weight of the master batch (100 parts by weight of rubber component), zinc white 3 parts by weight (Mitsui Kinzoku “Zinc Hana 1”), 1 part by weight of wax (“OZOACE0355” manufactured by Nippon Seiki), 2 parts by weight of sulfur (“5% oil-filled fine powder sulfur” by Tsurumi Chemical Industries), vulcanized 1 part by weight of an accelerator (“CBS” manufactured by Sanshin Chemical Co., Ltd.) was blended.

  Each rubber composition obtained was evaluated for dispersibility, fatigue, heat build-up, and processability, and Table 1 shows the results. Each evaluation method is as follows.

Dispersibility: Measured according to ASTM D2663 method B,
Fatigue property: Measured according to JIS K6270 and displayed as an index with Comparative Example 1 as 100. The larger the index, the better the fatigue resistance (crack resistance).
Exothermic property: The exothermic temperature was measured according to JIS K6265, and displayed as an index with Comparative Example 1 as 100. The smaller the index, the lower the heat generation temperature and the better the low heat generation.
Processability: The Mooney viscosity is measured according to JIS K6300-1, and is displayed as an index with Comparative Example 1 being 100. The smaller the index, the lower the Mooney viscosity and the better the processability.

  As shown in Table 1, in the rubber composition using the carbon black / natural rubber composite of the example according to the present invention, the dispersibility of the carbon black is clearly improved as compared with that of the comparative example. Fatigue, low heat generation, and workability were greatly improved.

[Examples 7 to 10]
(Production of master batch)
Master batches of Comparative Examples 6 to 8 and Examples 7 to 10 were prepared by the blending and mixing methods shown in Table 2 below. Comparative Example 6 is a mixture obtained by dry-mixing natural rubber and carbon black, and Comparative Examples 7, 8 and Examples 7-10 are a mixture of natural rubber latex and carbon black slurry. Each component in the table is as follows.

・ Natural rubber: RSS # 3,
・ Natural rubber field latex: “NR Latex” (rubber concentration DRC = 30% by weight) manufactured by Golden Hope
Concentrated natural rubber latex: “NR Latex” (Rubber Concentration DRC = 60% by weight) manufactured by Resitex Corporation,
Carbon black: Large particle size carbon “# 40” manufactured by Mitsubishi Chemical Corporation.

Carbon black slurry H: Carbon black (“# 40” manufactured by Mitsubishi Chemical Corporation) added to water so as to be 15% by weight and stirred with a stirrer (stirring speed: 50 m / sec).

Carbon black slurry I: After adding water to carbon black (“# 40” manufactured by Mitsubishi Chemical Corporation) so as to be 15 wt% and stirring with a stirrer (stirring speed: 50 m / sec), FIG. Dispersion treatment was performed in the dispersion treatment chamber shown (inner diameter = about 20 mm, length = about 25 cm, nozzle diameter of supply port (2) = 0.15 mm). The dispersion treatment was performed by injecting the slurry after stirring into the dispersion treatment chamber at a flow rate of 450 m / second (pressure of the high pressure generator = 101 MPa), and this dispersion treatment was passed five times.

Carbon black slurry J: Carbon black slurry I was prepared in the same manner except that the flow rate of the slurry was 600 m / second (pressure of the high pressure generator = 180 MPa).

Carbon black slurry K: Carbon black slurry I was prepared in the same manner except that the flow rate of the slurry was 700 m / second (pressure of the high pressure generator = 245 MPa).

Carbon black slurry L: In carbon black slurry I, carbon black with water and a dispersant (“Demol NL (Natrium salt of β-naphthalenesulfonic acid formalin condensate: anionic)” manufactured by Kao Corporation) 0.3 weight %, And the slurry flow rate was 700 m / second (pressure of the high pressure generator = 245 MPa), and the others were produced in the same manner.

-Mixing step by ultra high-speed flow: Using the mixing treatment chamber shown in FIG. 2 (inner diameter = about 5 mm, length = about 60 cm, nozzle diameter of the first supply port (12) = 0.15 mm), the carbon black Slurries H to L were injected from the first supply port (12) at a flow rate of 700 m / second (pressure of the high pressure generator = 245 MPa), and rubber latex was supplied from the second supply port (14).

(Evaluation of master batch)
A rubber composition was prepared using each of the above master batches. The composition of the rubber composition is 1 part by weight of stearic acid (manufactured by NOF Corporation), 1 part by weight of anti-aging agent (“6PPD” manufactured by Monsanto), 150 parts by weight of the master batch (100 parts by weight of rubber component), zinc white 3 parts by weight (Mitsui Kinzoku “Zinc Hana 1”), 1 part by weight of wax (“OZOACE0355” manufactured by Nippon Seiki), 2 parts by weight of sulfur (“5% oil-filled fine powder sulfur” by Tsurumi Chemical Industries), vulcanized 1 part by weight of an accelerator (“CBS” manufactured by Sanshin Chemical Co., Ltd.) was blended.

Each rubber composition obtained was evaluated for dispersibility, fatigue, heat build-up, and processability, and Table 2 shows the results. Each evaluation method is the same as in the case of Table 1 above. However, the indices of fatigue, exothermicity and workability are shown with Comparative Example 6 as 100.

Sectional view showing an example of a dispersion processing chamber Sectional view showing an example of a mixing chamber

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Dispersion processing chamber, 1a ... One end surface, 1b ... Other end part, 2 ... Supply port, 3 ... High pressure generator, 4 ... Discharge port, 10 ... Mixing processing chamber, 10a ... One end surface, 10b ... One end part, 10c ... other end, 12 ... first supply port, 13 ... high pressure generator, 14 ... second supply port, 15 ... rubber latex supply tank, 16 ... discharge port

Claims (6)

A dispersion step of finely dispersing the filler in the slurry by supplying the filler slurry containing the filler to the dispersion treatment chamber at a flow rate of 300 m / second or more;
And a mixing step of mixing the dispersion-treated filler slurry with concentrated natural rubber latex.   The dispersion treatment chamber has a cylindrical shape, and is provided with a supply port for supplying the filler slurry to one end surface in the axial direction, and a discharge port for the filler slurry subjected to the dispersion treatment at the other end portion in the axial direction. 2. The method for producing a rubber-filler composite according to claim 1, wherein the filler slurry is sprayed into the dispersion treatment chamber from the supply port at a flow rate of 300 m / second or more.   2. The rubber-filler composite according to claim 1, wherein in the mixing step, at least one of the dispersion-treated filler slurry and the concentrated natural rubber latex is supplied to a mixing chamber at a flow rate of 300 m / second or more to mix them. Body manufacturing method.   The mixing chamber has a cylindrical shape, and is provided with a first supply port for supplying one fluid of the filler slurry and the concentrated natural rubber latex to one end surface in the axial direction, and the one end portion in the axial direction is provided with the first supply port. A second supply port for supplying the other fluid of the filler slurry and the concentrated natural rubber latex is provided downstream of the first supply port, and a discharge port for discharging the mixed fluid at the other end in the axial direction. 4. The rubber-filler composite according to claim 3, wherein the one fluid is sprayed from the first supply port into the mixing chamber at a flow rate of 300 m / second or more. Production method.   A rubber-filler composite produced by the method according to claim 1.   A rubber composition using the rubber-filler composite according to claim 5.

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