JP5773010B1 - Tire puncture sealant - Google Patents

Abstract

Provided is a tire puncture sealant which has excellent freezing resistance and excellent sealing performance even when the amount of liquid is small. A tire puncture sealant comprising a rubber latex and / or a resin emulsion, a glycol ether represented by the following formula (1), and a surfactant. (In the formula (1), R1 represents a hydrogen atom or an alkyl group. P represents an integer of 1 or more.) [Selection] None

Description

  The present invention relates to a tire puncture sealant.

In recent years, puncture repair kits have been increasingly introduced as standard or optional equipment for automobiles.
The puncture repair kit is known to have a configuration in which a tire puncture sealant (tire puncture sealant) is combined with an optional compressor, and as an actual product, a tire called a “tire puncture emergency repair agent” or the like. A combination of a puncture sealant and a small-capacity compressor that takes power from a cigarette lighter socket and packaged in a compact manner is generally known.

  Here, the tire puncture sealant is required to be difficult to freeze (freeze resistance) even at low temperatures so that it can be used even in cold regions.

Under such circumstances, for example, in Patent Document 1, “in a tire puncture sealant containing natural rubber latex and / or synthetic resin emulsion and propylene glycol, the ratio of propylene glycol / water is 0.5 to 1.1. And a tire puncture sealant having a viscosity at −20 ° C. of 100 to 1200 mPa · s at a rotational speed of 60 rpm when a BL type viscometer is used. ”(Claim 1).
Patent Document 2 discloses “a tire puncture sealant containing natural rubber latex, a tackifier, 1,3-propanediol and a nonionic surfactant.” (Claim 1).
Patent Documents 1 and 2 describe that by adopting the above configuration, the injection property at a low temperature is excellent.

JP 2013-40297 A JP 2011-12158 A

On the other hand, along with a request for downsizing of a puncture repair kit, it is required to reduce the amount of tire puncture sealant (for example, to about 2/3 of the conventional level).
When the present inventor examined the tire puncture sealant disclosed in Patent Documents 1 and 2, it is surely excellent in freezing resistance, but with a smaller amount of liquid than the conventional one (about 2/3 of the conventional liquid amount). When used, it became clear that the sealing performance was not always sufficient.

  In view of the above circumstances, an object of the present invention is to provide a tire puncture sealant that has excellent freezing resistance and exhibits excellent sealing performance even when the amount of liquid is small.

As a result of intensive studies on the above problems, the present inventor has found that by adding a specific glycol ether, it exhibits excellent freezing resistance and excellent sealing properties even when the amount of liquid is small, leading to the present invention. It was.
That is, the present inventor has found that the above problem can be solved by the following configuration.

(1) A tire puncture sealant containing a rubber latex and / or a resin emulsion, a glycol ether represented by the formula (1) described later, and a surfactant.
(2) The tire according to (1), wherein the glycol ether content is 70 to 300 parts by mass with respect to 100 parts by mass in total of the solid content of the rubber latex and the solid content of the resin emulsion. Punk sealant.
(3) The tire puncture sealant according to (1) or (2) above, wherein the surfactant is a sulfate ester salt.
(4) Said (1)-(3) whose content of the said surfactant is 3-20 mass parts with respect to a total of 100 mass parts of solid content of the said rubber latex and solid content of the said resin emulsion. The tire puncture sealant according to any one of the above.
(5) The tire puncture sealant according to any one of the above (1) to (4), wherein p in formula (1) described later is an integer of 3 or more.

  As described below, according to the present invention, it is possible to provide a tire puncture sealant that has excellent freezing resistance and exhibits excellent sealing properties even when the amount of liquid is small.

The tire puncture sealant of the present invention will be described below.
In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

The tire puncture sealant of the present invention contains a rubber latex and / or a resin emulsion, a glycol ether represented by the formula (1) described later, and a surfactant.
Since the tire puncture sealant of the present invention has such a configuration, it is considered that the tire puncture sealant is excellent in freezing resistance and exhibits excellent sealing properties even when the amount of liquid is small. The reason is not clear, but it is presumed that it is as follows.

In tire puncture repair using a tire puncture sealant, the tire puncture sealant is injected into a punctured tire and the vehicle travels in that state. At this time, the tire puncture sealant is agitated in the tire, and as a result, the solid content in the tire puncture sealant is deposited and the puncture hole is closed.
Here, the tire puncture sealant injected into the tire may be agitated and bubbled by traveling. The present inventor has found that when the tire puncture sealant foams in this way, the apparent volume of the injected tire puncture sealant increases, and the sealing performance is maintained even if the amount of liquid is reduced. Furthermore, the tire puncture sealant formulated with the glycol ether (specific glycol ether) represented by the formula (1) described later has high initial foaming, and the foaming is maintained over time. I know.
The present invention is based on these findings, and by blending the specific glycol ether, the apparent volume of the injected tire puncture sealant increases, so that excellent sealing performance can be obtained even if the amount of liquid is reduced. It is thought that Moreover, since the specific glycol ether has a low freezing point, the tire puncture sealant of the present invention is considered to be excellent in freeze resistance.
In addition, since the tire puncture sealant of the present invention contains the specific glycol ether, it has a low viscosity and excellent injectability.
Hereinafter, each component contained in the tire puncture sealant of the present invention will be described.

[Rubber latex and / or resin emulsion]
The tire puncture sealant of the present invention contains a rubber latex and / or a resin emulsion. Among these, it is preferable to contain a rubber latex and a resin emulsion. That is, it is preferable to use rubber latex and resin emulsion in combination.
Hereinafter, the rubber latex and the resin emulsion will be described.

<Rubber latex>
The rubber latex is not particularly limited, and a conventionally known rubber latex can be used.
Specific examples of the rubber latex include natural rubber latex, chloroprene latex, styrene butadiene rubber latex, acrylonitrile butadiene rubber latex, styrene butadiene acrylic rubber latex, and the like. Of these, natural rubber latex is preferable.
In the tire puncture sealant of the present invention, the rubber latex can be used alone or in combination of two or more.

The natural rubber latex is not particularly limited, and a conventionally known natural rubber latex can be used.
Specific examples of natural rubber latex include those collected by tapping Hevea brasiliensis trees, so-called “deproteinized natural rubber latex” obtained by removing proteins from natural rubber latex, and the like.

  The solid content in the rubber latex is not particularly limited, but is preferably 40 to 80% by mass with respect to the entire rubber latex.

<Resin emulsion>
The resin emulsion is not particularly limited, and a conventionally known resin emulsion can be used. Of these, a synthetic resin emulsion is preferred.
Specific examples of the synthetic resin emulsion include urethane emulsion, acrylic emulsion, polyolefin emulsion, ethylene-vinyl acetate copolymer emulsion, polyvinyl acetate emulsion, ethylene-vinyl acetate-vinyl versatate copolymer emulsion, and polyvinyl chloride. An emulsion etc. are mentioned, These may be used individually by 1 type and may use 2 or more types together.
The resin emulsion is preferably an ethylene-vinyl acetate copolymer emulsion or an ethylene-vinyl acetate-vinyl versatate copolymer emulsion, more preferably an ethylene-vinyl acetate-vinyl versatate copolymer emulsion.

  The solid content in the resin emulsion is not particularly limited, but is preferably 30 to 70% by mass with respect to the entire resin emulsion.

In the tire puncture sealant of the present invention, the total content of the rubber latex and the resin emulsion is not particularly limited, but is preferably 30 to 80% by mass with respect to the entire tire puncture sealant.
The total content of the solid content of the rubber latex and the solid content of the resin emulsion is not particularly limited, but is preferably 10 to 50% by mass with respect to the entire tire puncture sealant.

[Glycol ether]
The tire puncture sealant of the present invention contains a glycol ether represented by the following formula (1).

In the above formula (1), R ₁ represents a hydrogen atom or an alkyl group. Of these, a hydrogen atom is preferable. The alkyl group is not particularly limited. The alkyl group may be linear, branched or cyclic, but is preferably linear.

  In the above formula (1), p represents an integer of 1 or more. Especially, it is preferable that it is an integer greater than or equal to 2, and it is more preferable that it is an integer greater than or equal to 3.

  Specific examples of the glycol ether include methyl glycol, methyl diglycol, methyl triglycol, methyl polyglycol, dimethyl glycol, dimethyl diglycol, dimethyl triglycol, dimethyl polyglycol and the like.

  In the tire puncture sealant of the present invention, the content of glycol ether is not particularly limited, but is 10 to 500 parts by mass with respect to 100 parts by mass in total of the solid content of the rubber latex and the solid content of the resin emulsion. It is preferably 50 to 300 parts by mass, more preferably 70 to 300 parts by mass, and particularly preferably 100 to 300 parts by mass.

[Surfactant]
The surfactant contained in the tire puncture sealant of the present invention is not particularly limited, and a conventionally known surfactant can be used. Specific examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, and zwitterionic surfactants. Surfactant may be used individually by 1 type and may use 2 or more types together.

Nonionic surfactants include, for example, fatty acid sorbitan esters, polyoxyethylene fatty acid sorbitans, polyoxyethylene higher alcohol ethers, polyoxyethylene-propylene higher alcohol ethers, polyoxyethylene fatty acid esters, polyoxyethylene alkylphenols, polyoxyethylenes. Examples thereof include alkylamines and polyoxyethylene-polyoxypropylene block polymers.
Examples of the anionic surfactant include fatty acid salts, alkyl sulfates, alkyl ether sulfate esters, alkyl ester carboxylates, alkyl benzene sulfonates, linear alkyl benzene sulfonates, alpha sulfo fatty acid ester salts, alkyl polyoxy Examples thereof include ethylene sulfate, alkyl phosphate, monoalkyl phosphate ester salt, naphthalene sulfonate, alpha olefin sulfonate, alkane sulfonate, and alkenyl succinate.
Examples of the cationic surfactant include quaternary ammonium salts such as alkylamine acetate and alkyltrimethylammonium chloride.
Examples of the zwitterionic surfactant include dimethylalkyl betaine and alkylamide betaine.

  The surfactant is preferably at least one surfactant selected from the group consisting of a nonionic surfactant and an anionic surfactant, more preferably an anionic surfactant, and a sulfate ester. More preferably, it is a salt.

  The sulfate ester salt is not particularly limited, but is preferably an alkyl sulfate ester salt or a polyoxyethylene alkyl ether sulfate ester salt, and more preferably a compound represented by the following formula (2) or (3).

In the above formulas (2) and (3), R ₂ and R ₃ each independently represent an alkyl group having 1 to 20 carbon atoms, M ⁺ represents a monovalent cation, and n represents 1 to 15 Represents an integer.

In the above formulas (2) and (3), examples of the alkyl group having 1 to 20 carbon atoms represented by R ₂ and R ₃ include, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl Group, octyl group, ethylhexyl group, nonyl group, decyl group, dodecyl group (lauryl group), undecyl group, hexadecyl group, octadecyl group, cyclopropylmethyl group, trifluoroethyl group and the like. Twenty long chain alkyl groups are preferred. The alkyl group may be linear, branched or cyclic, but is preferably linear.

In the above formulas (2) and (3), examples of the monovalent cation represented by M ⁺ include monovalent metal cations (for example, alkali metal cations), ammonium cations, and the like. The cation represented by (4) is preferred.

In the above formula (4), R _{41 to} R ₄₄ each independently represent a hydrogen atom, an alkyl group (for example, an alkyl group having 1 to 5 carbon atoms), or an alkyl group having a hydroxy group (for example, —R— OH: Here, R represents an alkylene group (preferably an alkylene group having 1 to 5 carbon atoms). At least one of R _{41 to} R ₄₄ is preferably an alkyl group having a hydroxy group.
Examples of the cation represented by the above formula (4) include triethanolammonium.

  In the tire puncture sealant of the present invention, the content of the surfactant is not particularly limited, but is 0.1 to 30 mass with respect to a total of 100 mass parts of the solid content of the rubber latex and the solid content of the resin emulsion. Part, preferably 1 to 20 parts by weight, and more preferably 3 to 20 parts by weight.

[Optional ingredients]
The tire puncture sealant of the present invention may contain components (arbitrary components) other than the above-described components as necessary. Examples of such optional components include antifreeze agents, fillers, anti-aging agents, antioxidants, pigments (dyes), plasticizers, thixotropic agents, ultraviolet absorbers, flame retardants, dispersants, and dehydrating agents. And antistatic agents.

[Method for producing tire puncture sealant]
The manufacturing method in particular of the tire puncture sealant of this invention is not restrict | limited, For example, the method etc. which mix each component mentioned above using a stirrer etc. are mentioned.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these.

<Manufacture of tire puncture sealants>
The components shown in Table 1 below were mixed at a ratio (parts by mass) shown in the same table using a stirrer to produce tire puncture sealants (tire puncture sealants of Examples and Comparative Examples). In Table 1, the numbers in parentheses for rubber latex and resin emulsion represent mass parts of solid content.

<Loss miles test>
The obtained tire puncture sealant was subjected to a loss miles test. Specifically, with respect to the obtained tire puncture sealant, according to JIS K3362: 2008, “the height of the foam immediately after all the solution flows out” (the height of the initial foam), and “all the solutions The height of the foam after 5 minutes ”(the height of the foam after 5 minutes) was measured. The results are shown in Table 1.

<Sealability>
The resulting tire puncture sealant was evaluated for sealability as follows.
A puncture hole (diameter 4 mm) was made in the shoulder groove portion of the tire tread.
Next, the tire with puncture holes was mounted on a drum testing machine, and 300 ml of the obtained tire puncture sealant was injected from the valve port of the tire, and air was filled so that the tire internal pressure was 150 kPa. The 300 ml corresponds to about 2/3 of the conventional liquid volume.
Thereafter, the intermittent operation in which the tire was run for 1 minute and stopped under conditions of a load of 350 kg and a speed of 30 km was repeated until there was no air leakage (until sealing). The presence or absence of air leakage was confirmed visually and by spraying soapy water near the puncture hole.
And the sealing performance was evaluated according to the following criteria. The results are shown in Table 1. From the viewpoint of sealing properties, A or B is preferable, and A is more preferable.
A: Sealed within 5 cycles of intermittent operation.
B: Sealed in intermittent operation 6 to 10 cycles.
C: Sealed after 11 cycles or more of intermittent operation.

<Freezing resistance>
The resulting tire puncture sealant was evaluated for freezing resistance according to the following criteria. The results are shown in Table 1. From the viewpoint of freezing resistance, A is preferable.
A: Do not freeze at -40 ° C.
-B: Freeze at -40 ° C.

The details of each component shown in Table 1 are as follows.
・ Rubber latex: Natural rubber latex (Hytex HA, solid content: 60% by mass, manufactured by Felfex (handled by Nomura Trading Co., Ltd.))
Resin emulsion: ethylene-vinyl acetate-vinyl versatate copolymer emulsion (Sumikaflex 950HQ, solid content: 50% by mass, manufactured by Sumika Chemtex Co., Ltd.)
-Propylene glycol: Propylene glycol-Ethylene glycol: Ethylene glycol-1,3-propanediol: 1,3-propanediol-Methyltriglycol: Methyltriglycol (glycol ether represented by the above formula (1). R ₁ : hydrogen atom, p = 3.)
Methyl diglycol: methyl diglycol (glycol ether represented by the above formula (1). Here, R ₁ : hydrogen atom, p = 2.)
Surfactant 1: lauryl sulfate triethanolamine (Emar TD, molecular weight: 405, manufactured by Kao Corporation) (compound represented by the above formula (2). Here, R ₂ : lauryl group (n-dodecyl group), M ⁺ : a cation represented by the above formula (4) (where R _{41 is a} hydrogen atom, R _{42 to} R ₄₄ : —CH ₂ CH ₂ OH).)
Surfactant 2: ammonium lauryl sulfate (Latemul AD-25, manufactured by Kao Corporation)

As can be seen from Table 1, all of the examples of the present application containing rubber latex and / or resin emulsion, glycol ether represented by the above formula (1) and surfactant are excellent in freezing resistance, and liquid Excellent sealing performance even with a small amount.
From the comparison between Examples 1 and 4, Example 1 in which p in the above formula (1) is an integer of 3 or more showed better sealing properties.
From the comparison of Examples 1 to 3, Examples 1 and 3 in which the content of glycol ether is 70 to 300 parts by mass with respect to 100 parts by mass in total of the solid content of the rubber latex and the solid content of the resin emulsion Excellent sealing performance was exhibited.
From the comparison between Examples 1 and 8, the surfactant is a compound represented by the above formula (2), and M ⁺ in the above formula (2) is a cation represented by the above formula (4). In addition, Example 1 in which at least one of R _{41 to} R _{44 in} the above formula (4) is an alkyl group having a hydroxy group showed better sealing properties.
Further, from the comparison of Examples 1 and 5 to 7, Example 1 in which the content of the surfactant is 3 to 20 parts by mass with respect to 100 parts by mass in total of the solid content of the rubber latex and the solid content of the resin emulsion. , 6 and 7 showed better sealing properties.

  On the other hand, in Comparative Examples 1 to 5 not containing the glycol ether represented by the above formula (1), the sealing performance was insufficient when the liquid amount was small.

Claims (5)

A tire puncture sealant containing a rubber latex and / or resin emulsion, a glycol ether represented by the following formula (1), and a surfactant.
(In formula (1), R ₁ represents a hydrogen atom or an alkyl group. P represents an integer of 1 or more.)   The tire puncture sealant according to claim 1, wherein a content of the glycol ether is 70 to 300 parts by mass with respect to 100 parts by mass in total of a solid content of the rubber latex and a solid content of the resin emulsion.   The tire puncture sealant according to claim 1 or 2, wherein the surfactant is a sulfate ester salt.   The content of the surfactant is 3 to 20 parts by mass with respect to a total of 100 parts by mass of the solid content of the rubber latex and the solid content of the resin emulsion. The tire puncture sealant described in 1.   The tire puncture sealant according to any one of claims 1 to 4, wherein p in the formula (1) is an integer of 3 or more.