KR100593031B1 - Inside lubricant composition for green tire - Google Patents

Abstract

The present invention relates to an internal lubricant composition for a green tire, and more particularly, a lubricant used in a green tire when manufacturing a tire, to impart releasability and lubricity between an inside of a green tire and a vulcanizer brada, and in particular, an interface between tire rubber elements. The present invention relates to an internal lubricant composition for a green tire that does not degrade adhesiveness while maintaining general release properties and lubricity.

An object of the present invention is to provide a lubricant composition that can improve the release property and lubricity between the interior of the green tire and the brada.

The internal lubricant composition for green tire of the present invention is 8 to 10% by weight of hydrosil-organic polysiloxane, 2 to 4% by weight of inorganic fillers selected from mica, talc, clay and calcium carbonate, and 3 to 5% by weight of polyisoprene rubber. 1 to 2% by weight of fatty acid, 2 to 3% by weight of polyethylene glycol, 3 to 5% by weight of nonionic surfactant, 2 to 3% by weight of anionic surfactant, and the balance of water.

Description

Inside lubricant composition for green tire

The present invention relates to an internal lubricant composition for a green tire, and more particularly, a lubricant used in a green tire when manufacturing a tire, to impart releasability and lubricity between an inside of a green tire and a vulcanizer brada, and in particular, an interface between tire rubber elements. The present invention relates to an internal lubricant composition for a green tire that does not degrade adhesiveness while maintaining general release properties and lubricity.

The internal lubricant used in the tire is evenly applied to the inner part of the molded green tire, and evaporates the moisture of the coating film after a certain time to maintain the film, and then in the vulcanizer, a vulcanizing bladder in the mold. And green tires, especially the vulcanization bladder and the inner part of the green tires to give all the releasability, to provide the lubricity when the brada is pushed into the mold cavity of the green tires and to help the air between the contacting interface to escape well Giving will also function.

After the green tire is vulcanized at a high temperature for a certain time, the components of the lubricant applied to the inner surface of the tire are formed into a stable coating, and when the mold is demolded from the mold, the components of the applied lubricant are adhered as they are to exhibit mold release properties.

At this time, solids such as inorganic fillers should not be separated during the expansion and contraction of the brada.

In general, the inner part of the tire is a rubber composition composed mainly of butyl rubber with good air permeability in order to maintain the air inside, and has low interfacial strength due to extremely low reactivity between other elements during vulcanization. If components are introduced or buried, it is difficult to maintain safe quality because of no interfacial adhesion.

In the case of a tube-type large tire, the tire is attached to the vehicle, and then the tire is not in contact with the inside of the tire while driving. There is a risk of giving.

Therefore, the film stability of the lubricant inside the tire should be helpful to the reduction of friction and the minimum flow stability. As a result, internal lubricants can be critical for active response to harsh driving conditions as well as tire manufacturing processes. In addition to maintaining the release properties and lubricity, which are the main functions of the lubricant, it is very important to maintain adhesion at the rubber interface, which can greatly affect tire quality.

The conditions required for the lubricant used in the interior of the green tires include high lubrication and release property, high air breed, elimination of harm to brada life, storage stability, elimination of harmfulness, high adhesion to inner areas, Maintain adhesion between interfaces after heat treatment, heat resistance, etc.

In addition, various deletion methods for side effects of the internal lubricant of the tire have been variously examined, but sufficient fairness needs to be reflected.

The lubricant of the present invention is an improved composition, unlike the keying interior composition, in order to maintain the quality of the interfacial adhesion even when applied directly to the rubber interface during the manufacturing process of a large tire. In addition, through the application of fairness and quality verification, the internal lubricant for large tires was intended to eliminate the manifestations and side effects of various functions.

Conventionally, the main component of the mold release agent inside the tire is an additive mixed with silicone oil including inorganic filler as a main component, and during storage, during the application process, the storage stability decreases, which causes viscosity non-uniformity due to precipitation and uniformity of particles when applied through a gun. There is also a problem with falling sex. In particular, as the lubrication degree over time when the solution is left for a long time, silicon or the like is adsorbed to the inorganic filler, which also causes a decrease in function.

In addition, when applied to green tires are scattered from the environmental point of view and waste pollution such as sludge is generated.

Conventional inorganic filler / silicone oil-based internal lubricants may be contaminated by the inorganic filler applied during the vulcanization process after the vulcanization, the inorganic filler is weak adhesion to the mold and brada.

In the case of using a tube, including a large tire, strengthening of interfacial adhesion is more required. In addition, the use of a protective vinyl tape to prevent the contamination of the lubricant on the internal joints during the manufacturing process of the green tire is required to improve in terms of productivity and efficiency due to the additional process.

Accordingly, various researches have been made on internal lubricants, including tires, and efforts are being made to improve them.

Therefore, it is necessary to examine to maintain and show the bonding strength between rubbers while meeting the improvement of tire quality after lubrication, mold release, and environmental pollution.

On the other hand, as a prior art related to the present invention, there is a tire release agent in which 0.5 to 1.5% by weight of polyethylene glycol (PEG) having an average molecular weight of 8000 is added as a gelling agent.

In addition, Korean Laid-Open Patent Publication No. 2000-0025204 discloses a mixture of internal mold release agent composition consisting of mica powder, lamp black, surfactant, polyethylene olein ether, silicone oil, polyethylene glycol, and lecithin with water in a 1: 1 ratio of 50, The contents of the release product of the green tire internal release which improves the external pollutability of less than 00CPC and the hydrogen ion index of 7 to 8 and the friction coefficient of 0.3 or less are described.

However, these prior arts differ from the technical composition of lubricant compositions consisting of hydrosil-organic polysiloxanes, inorganic fillers, polyisoprene rubbers, fatty acids, polyethylene glycols, nonionic surfactants, anionic surfactants and the balance of water.

The present invention devised to solve the above-mentioned problems has been completed by studying the composition of the lubricant that can improve the release property and lubricity between the interior of the green tire and the brada.

Therefore, an object of the present invention is to provide a lubricant composition which can improve the release property and lubricity between the interior of the green tire and the brada.

In other words, unlike conventional internal lubricants, lubricants for releasing, lubricating, and air breeding characteristics in order to smooth the airflow characteristics between the vortex breda inside the large green tires while preventing the vulcanization adhesion between the rubber interfaces inside the tire from dropping. It is for the purpose of providing a composition.

The lubricant composition used in the tire of the present invention for achieving the above-mentioned object is a conventional lubricant used in the tire,

8-10% by weight of hydrosil-organic polysiloxane, 2-4% by weight of inorganic filler, 3-5% by weight of polyisoprene rubber, 1-2% by weight of fatty acid, 2-3% by weight of polyethylene glycol, 3-5% of nonionic surfactant It is possible to provide a lubricant composition composed of weight%, anionic surfactant 2 to 3 weight% and the balance of water.

Hydrosil-organopolysiloxane in the lubricant composition of the present invention can be used as a release agent.

In the lubricant composition of the present invention, the inorganic filler may be an inorganic filler used in a conventional lubricant composition. As an example of such an inorganic filler in the present invention, any one selected from mica, talc, clay, calcium carbonate (CaCO ₃ ), or two or more thereof may be used. In this case, two kinds of inorganic fillers may be used by mixing them in a weight ratio of 1: 9 to 9: 1.

In the lubricant composition of the present invention, the polyisoprene rubber is used to improve the adhesive force between the interface between the green tire and the vulcanization brada. In the present invention, the polyisoprene rubber may have an average molecular weight of 30,000 to 50,000.

In the lubricant composition of the present invention, any fatty acid may be used as long as the fatty acid is used to suppress a decrease in viscosity of the lubricant.

As an example of the fatty acid in the present invention, a fatty acid having 16 to 18 carbon atoms can be used. Meanwhile, as an example of the fatty acid, palmitic acid having 16 carbon atoms or stearic acid having 18 carbon atoms may be used.

Polyethylene glycol (PEG) in the lubricant composition of the present invention can be used as an emulsifier and dispersant in the lubricant composition.

Polyethylene glycol having such a role in the present invention can be used that has an average molecular weight of 200 to 500.

Nonionic surfactants and anionic surfactants are used to improve the dispersibility of the lubricant compositions of the present invention, and any surfactant can be used as long as they are used in conventional lubricant compositions.

Glyceryl fatty acid esters may be used as an example of such nonionic surfactants in the present invention. And as an example of anionic surfactant, a tauric acid salt can be used.

Purified water in the present invention can be used as a solvent of the composition of the lubricant.

The lubricant composition is applied in various amounts to the internal lubricant composition for the green tire of the present invention, and the lubricant composition meeting the object of the present invention is preferably used in the above-described numerical range.

Hereinafter, the present invention will be described by the following comparative examples, examples and test examples. However, these are not limited to the scope of the present invention by these as an embodiment of the present invention.

<Example 1>

After heating the purified water to 40 ° C. as shown in Table 1 below, 9% by weight of hydroxyl-organic polysiloxane, 4% by weight of liquid polyisoprene rubber having an average molecular weight of 40,000, and 3% by weight of fatty acid having 16 carbon atoms (palmitic acid) %, 2% by weight of polyethylene glycol having an average molecular weight of 300%, 5% by weight of nonionic surfactant (glyceryl fatty acid ester) usually used for lubricants, anionic surfactants (tauuric acid salts) usually used for lubricants 3 Weight percent was added and stirred at 100 rpm for 30 minutes to mix.

Then, talc 2% by weight was added to the mixed solution containing hydroxyl-organic polysiloxane as an inorganic filler and stirred for 30 minutes at 100 rpm again to prepare a lubricant.

<Example 2>

A lubricant was prepared in the same manner as in Example 1, except that 6% by weight of hydroxyl-organic polysiloxane and 2% by weight of polyisoprene rubber were used.

<Example 3>

A lubricant was prepared in the same manner as in Example 1, except that 11% by weight of hydroxyl-organic polysiloxane and 6% by weight of polyisoprene rubber were used.

<Example 4>

A lubricant was prepared in the same manner as in Example 1, except that 5% by weight of fatty acid was used.

Example 5

A lubricant was prepared in the same manner as in Example 1, except that 5% by weight of fatty acid and 4% by weight of talc were used.

Comparative Example

After the purified water was heated to 40 ° C. as shown in Table 1 below, 10% by weight of silicone oil, 2% by weight of polyethylene glycol having an average molecular weight of 300%, 5% by weight of nonionic surfactant (glyceryl fatty acid ester), anionic 3 weight% of surfactant (tauric acid salt) was added, and it stirred and mixed at 100 rpm for 30 minutes.

Then, 25% by weight of mica was added to the mixed solution containing the silicone oil as an inorganic filler, and again stirred at 100 rpm for 30 minutes to prepare a lubricant.

TABLE 1 Lubricant Composition Components (Unit: Weight%) of Comparative Example and Example

Item Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Mica 25 - - - - - Talc - 2 2 2 2 4 Silicone oil 10 - - - - - Hydroxyl-organopolysiloxanes - 9 6 11 9 9 Polyisoprene rubber - 4 2 6 4 4 fatty acid - 3 3 3 5 5 Polyethylene glycol 2 2 2 2 2 2 Nonionic surfactant 5 5 5 5 5 5 Anionic surfactant 3 3 3 3 3 3 Purified water 55 72 77 67 70 68

<Test Example 1>

Physical properties such as solid content, ash, viscosity, and pH of the lubricants prepared in Examples and Comparative Examples were measured by ASTM-related regulations, and the results are shown in Table 2 below.

It can be seen that the solid content of the lubricant of the example is superior to that of the comparative example.

<Table 2> Measurement of physical properties of Comparative Examples and Examples

Item Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Solid content (%) 38.2 44.1 41.54 46.5 43.8 45.5 Ash content (%) (55 ℃, 2hr) 23.7 29.1 27.3 32.9 30.0 30.0 Viscosity (CPS) 1100 1000 950 1250 990 1050 pH 8.1 8.4 8.0 8.5 7.9 7.8

<Test Example 2>

The lubricant prepared in Examples and Comparative Examples was applied between the green tire and the brada, followed by vulcanization to prepare the tire, followed by drying time, rubber surface wettability, filler separation degree, and rubber vulcanization for the lubricant applied to the tire. Physical properties such as adhesion, air bleed, film stability, and crack growth were measured by ASTM-related regulations, and the results are shown in Table 3 below.

TABLE 3 Measurement of physical properties of Comparative Examples and Examples

Item Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Drying time 16.5 minutes 15.4 minutes 15.0 minutes 17.5 minutes 17.0 minutes 16.5 minutes Rubber Surface Wetting usually Good usually usually Good usually Filler separation degree usually Extremely low Good Good Good usually Vulcanization adhesion between rubbers 5kgf or less 20kgf or less 15kgf or less 20kgf or less 13kgf or less 10kgf or less Air breed Good Good usually Good usually Good Anti-sagging Good Good usually Good usually usually Crack growth (mm) none none none none none none

As shown in the results of Table 3 above, when the tire was manufactured using the lubricant composition of the present invention, the rubber of the comparative example had a physical property equivalent to or higher than that of the lubricant of the comparative example, and in particular, the degree of peeling of the filler and the rubber had an excellent effect on the vulcanization adhesion. And it was found.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the present invention without departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that it can be changed.

Claims (3)

In the internal lubricant composition for green tires, 8-10 wt% of hydrosil-organic polysiloxane, 2-4 wt% of inorganic fillers selected from mica, talc, clay, calcium carbonate, 3-5 wt% of polyisoprene rubber, 1-2 wt% of fatty acid, polyethylene glycol The internal lubricant composition for green tire which consists of 2-3 weight%, 3 to 5 weight% of nonionic surfactants, 2-3 weight% of anionic surfactants, and remainder of water. The internal lubricant composition for a green tire according to claim 1, wherein the polyisoprene rubber has an average molecular weight of 30,000 to 50,000. The internal lubricant composition for a green tire according to claim 1, wherein the fatty acid is a fatty acid having 16 to 18 carbon atoms.