JP2525857B2 - Adhesive comprising 3,5-xylenol-resorcinol-formaldehyde condensation resin composition and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention can be preferably used as an adhesion aid for favorably adhering rubber and polyester fiber as a reinforcing material thereof, for example, 3,5-xylenol resorcinol. More specifically, the present invention relates to an adhesive containing a formaldehyde condensation resin composition and a method for producing the adhesive, and more specifically, by mixing and using it in RFL which is a general adhesive between a rubber and a fiber-reinforced material, the rubber and the polyester of the adhesive are used. 3,5-xylenol-resorcinol, which can significantly improve the adhesive strength with fibers
The present invention relates to an adhesive containing a formaldehyde condensation resin composition and a method for producing the adhesive.

<Prior Art> Polyester fiber, which is a linear polymer with an ester bond in the main chain, retains stable mechanical properties compared to fibers such as nylon, less stress relaxation, creep properties and elongation elastic recovery. The rate is excellent. Therefore, the polyester fiber is extremely useful as a reinforcing material for rubber articles such as tires, belts, air springs and rubber hoses, and is used in the form of filaments, yarns, cords, cables, cord fabrics, canvas and the like.

However, when polyester fiber is used as a reinforcing material for these rubber articles, as an adhesive between rubber and polyester fiber, resorcinol formaldehyde used as a good adhesive when a fiber such as nylon or rayon is used as a reinforcing material. Condensate (hereinafter referred to as RF)
It is not possible to obtain a sufficient adhesive force even if the adhesive liquid RFL composed of rubber latex is used.

This is because polyester fibers are denser in terms of higher-order structure and have less functional groups than fibers such as nylon and rayon.

Therefore, as a method of improving the adhesive force between the rubber and the polyester fiber, the polyester fiber surface is preliminarily treated with epoxy (JP-A-39-10514) or isocyanate (UK Patent 816640) to modify the RFL. A method of using a two-component adhesive has been proposed in which it is used to adhere to rubber.

However, since the isocyanate compound and the epoxy compound have high reactivity, they react with water, which is a solvent of RFL, and RFL. Therefore, such a reactive adhesive cannot be a one-component adhesive. Therefore, in such a method, it is necessary to perform the adhesive treatment of the polyester fiber in two steps, and there is a cost problem that extra equipment and heat are required. Further, there is a problem that a large amount of smoke is generated in the heat treatment step of the adhesive-treated polyester fiber, which is not preferable from the viewpoint of environmental pollution.

Further, as a serious problem, regarding the adhesive force between the rubber and the polyester fiber adhered by such a method, although the initial adhesive force is high, there is a problem that a rapid adhesive deterioration occurs when used at high temperature. there were.

On the other hand, as a one-pack type adhesive, there has been proposed one in which RFL is mixed with a phenol, a methylol compound of phenol with formaldehyde, and a cocondensate obtained by reacting resorcin (JP-A-46-11251). See the bulletin).

However, among the co-condensates, those specifically mentioned are the co-condensates of resorcin or alkylresorcin derivative, o-, p-alkyl or halogenphenol, and formaldehyde. In this case, since the electrophilic reaction site (ortho or rose position) of the phenol part of the cocondensate is lost, the reactivity with RF in RFL is low even when mixed with RFL. Therefore, even if such an adhesive is used, there is a problem in that the adhesive strength required in the rubber industry is insufficient.

Another known one-component adhesive is a mixture of 3,5-xylenol-resorcinol-formaldehyde resin and RFL. In this case, 3,5-xylenol
It is said that the average molecular weight of the resorcin-formaldehyde condensation resin is preferably about 300 to 1000 from the viewpoint of the adhesiveness between the polyester fiber of the resin and the rubber.

However, the 3,5-xylenol-resorcinol-formaldehyde condensation resin has a
-Since resorcin has extremely high reactivity with formaldehyde as compared with xylenol, there is a problem that a condensation reaction product of resorcin and formaldehyde is mainly produced.

In order to solve such problems, JP-A-57-167312 discloses a method of producing a condensate by first reacting 3,5-xylenol with methylol and then reacting the methylol compound with resorcin. ing.

However, as a result of additional tests by the present inventor, the target 3,5-xylenol methylol compound was contained in the methylolated product formed by such a method only at a level of 30 area% or more, and most of the rest remained. It was a condensation reaction product of methylol compounds. Therefore, when such a methylol compound and resorcin are condensed, the average molecular weight is about 1300.
A resin having a high molecular weight is obtained. Therefore, such a resin has a problem that it is not preferable to be used as a raw material of an adhesive because the adhesiveness to a polyester fiber is extremely poor.

<Problems to be Solved by the Invention> The present invention is intended to solve the problems associated with the above-mentioned two-pack adhesive and the one-pack adhesive using a conventional 3,5-xylenol / resorcin / formaldehyde condensation resin. An adhesive containing a resin composition for an adhesion aid, which is a raw material of a one-component adhesive, capable of reducing the cost of the adhesive treatment between rubber and polyester fiber and preventing environmental pollution, and It is an object to provide a method for producing the adhesive.

Further, the present invention provides an adhesive containing a resin composition for an adhesive aid for increasing the adhesive force between the rubber and the polyester fiber of the one-pack type adhesive agent and preventing the deterioration of the adhesive force even at high temperature. An object of the present invention is to provide an agent and a method for producing the adhesive.

Here, the one-pack type adhesive agent contains RFL and an adhesion aid, and means a material that firmly bonds the rubber and the polyester fiber in one step treatment.

<Means for Solving Problems> Therefore, the present inventors diligently studied 3,5-xylenol / resorcinol / formaldehyde resin as an adhesion aid for a one-pack type adhesive in order to achieve the above object. As a result, the 3,5-xylenol-resorcinol-formaldehyde resin is a binuclear body represented by the following formula (I) as a representative example, a trinuclear body represented by the formula (II) as a representative example, and 4 to 6 depending on the production conditions.
It was found to consist of nuclei and high molecular weight compounds of 7 nuclides or more.

Regarding the relationship between the composition of various nuclides constituting 3,5-xylenol-resorcinol-formaldehyde resin and the adhesive force when it is used in a one-component adhesive, it is necessary to develop high adhesive force. The condition is an area% of 4 to 6 nuclear bodies.
The ratio obtained by dividing (S _4-6 ) by the area% (ΔS ₂ ) obtained by subtracting the area% (S ₁ ) of the mononuclear body from the area% (100 area%) of the entire condensate Content of 4 to 6 nuclides] is 27 to 43 area% and area% of polynuclear bodies of 4 or more nuclides (S _4- )
And the fused polymer entire area% (100 area%) from the area% of the mononuclear body (S ₁₎ and subtracted by comprising area% (△ S ₁₎ obtained by dividing the ratio [4 or more nuclei of multinuclear Body content] is 60-73 area%
It has been found that it is preferable that the molar ratio of 3,5-xylenol methylol compound to be reacted with resorcin be within a certain range.

The polynuclear body content of 4 or more nuclear bodies and 4
~ 6-nuclear body content means GPC analysis (column; Toyo Soda G30
Direct connection of 00HXL and G2000HXL, solvent: tetrahydrofuran 0.4 ml / min, detector: differential refractometer SE-3 manufactured by Shoden
1) From the results, it is the composition ratio of the components obtained by the following formula.

Another factor that controls the adhesive strength is 3,5
-There is 2,6-dimethylol-3,5-xylenol concentration in 3,5-xylenol methylol compound, which is a raw material for producing xylenol-resorcinol-formaldehyde condensation resin, and it is preferable that the concentration is a specific concentration or more. I found it.

Furthermore, in order to obtain a specific polynuclear 3,5-xylenol-resorcinol-formaldehyde condensation resin as described above, or as a 3,5-xylenol methylol compound at a specific concentration or more 2,6-dimethylol-3,5-xylenol. In order to obtain those containing 3,5-xylenol, when the methylolation of 3,5-xylenol is performed with formaldehyde, the condensation product of the methylolated products is not formed, and the composition of various formed methylated products can be controlled. Is necessary, and for that, 3,
It has been found that the reaction of 5-xylenol with formaldehyde may be carried out in the presence of a constant concentration of a base, an organic solvent capable of dissolving the resulting 3,5-xylenol methylol compound and water.

The present invention has been completed based on the above findings.

That is, the present invention relates to 3,5-xylenol resorcin.
With respect to the 3,5-xylenol-resorcinol-formaldehyde condensate represented by the following formula (a) in the formaldehyde condensation resin composition, the area% of the polynuclear body of four or more nuclides in which n is 2 or more in the formula (a) ( S _4- ) is the area% of the entire condensate (100 area%) to the area% of the mononuclear body (S ₁ )
The ratio [4 obtained by dividing by the area% (△ S ₁ )
Polynuclear body content of nucleolar or higher] is 60 to 73 area%, and area% of 4 to 6 nucleolus, in which n in formula (a) is 2 to 4
The ratio obtained by dividing (S _4-6 ) by the area% (ΔS ₂ ) obtained by subtracting the area% (S ₁ ) of the mononuclear body from the area% (100 area%) of the entire condensate 4-6 core content] is 27-43 area%, and a rubber and fiber having excellent high-temperature resistance, which contains RFL and an adhesion aid composed of a 3,5-xylenol-resorcinol-formaldehyde condensation resin composition And a one-pack adhesive.

In addition, the present invention, 3,5-xylenol and formaldehyde or formaldehyde generating compound 0.5-1.5 equivalents to 3,5-xylenol base, the presence of water and an organic solvent capable of dissolving 3,5-xylenol methylol compound Of the 3,5-xylenol methylol compound formed by reacting below, the content of 2,6-dimethylol-3,5-xylenol is 25 area% or more, methylation of 3,5-xylenol, The 3,5-xylenol methylol compound and resorcinol are reacted in the presence of an acid catalyst to give 3,5-
Provided is a method for producing a one-pack type adhesive composed of rubber and fibers, which is excellent in high temperature resistance and is characterized by producing an adhesion aid comprising a xylenol / resorcin / formaldehyde condensation resin composition and mixing it with RFL.

In the above invention, the organic solvent capable of dissolving the 3,5-xylenol methylol compound is preferably 0.5 mol or more with respect to the 3,5-xylenol. It is preferable that the water has a molar ratio with respect to the 3,5-xylenol of 15 or less, and the formaldehyde or the formaldehyde-generating compound has a molar ratio with respect to 3,5-xylenol of 0.5 to 3 in terms of formaldehyde. Is preferred. It is preferable that the resorcinol has a molar ratio of 1 to 5 with respect to the 3,5-xylenol methylol compound.

<Structure of the Invention> The structure of the present invention will be described in detail below.

The 3,5-xylenol-resorcinol-formaldehyde condensation resin composition of the present invention is such that the content of various polynuclear bodies in the condensate constituting the same is within a certain range, that is, the area of the polynuclear body having 4 or more nuclides. % of (S _4-), the ratio obtained by dividing the area percent of the total said reduced coalescence area% mononuclear body from (100 area%) (S ₁₎ area% made by subtracting the (△ S ₁₎ [ Polynuclear body content of 4 or more nuclei] is 60 to 73 area%, and 4 to 6
The area% (S _4-6 ) of the nucleus is calculated as the area% (100% of the whole condensate).
Area% mononuclear body from the area%) (S ₁₎ area% made by subtracting the (△ S ₂₎ [content of 4-6 nuclei] divided by the ratio obtained by
Is characterized by 27 to 43 area%. This is because when the content of each nucleus is in this range, high adhesive strength is exhibited.

This is based on the results of the present inventors' study of the contribution of each nucleus to the adhesive force.

That is, the present inventors have synthesized various 3,5-xylenol / resorcinol / formaldehyde condensation resin compositions by changing the reaction molar ratio of resorcin to 3,5-xylenol methylol compound in the range of about 1 to 10. , GPC analysis of the core composition of each condensation resin composition, GPC analysis of the core composition of the condensation resin composition, each core content (GPC composition) in the condensation resin and each condensation resin composition RFL The relationship with the adhesive force of the adhesive mixed in was analyzed. As a result, as shown in FIG. 1 (a) and FIG. 1 (b), the contribution of each nucleus to the adhesive force was as follows.

1 to 3 nuclei << 7 nuclei or more <4 to 6 nuclei Small → adhesive strength → large Thus, it is understood that increasing the content of 4 to 6 nuclides is important for increasing the adhesive strength.

Furthermore, the present inventors have made various changes in the methylolation reaction conditions of 3,5-xylenol and the condensation reaction conditions of 3,5 xylenol methylol compound and resorcin to various 3,5-xylenol / resorcin / formaldehyde condensation reaction. Synthesizing resin composition, GP of those condensation resin composition
The multiple correlation analysis was performed on the relationship between the C composition and the adhesive force of the adhesive in which each condensation resin was mixed with RFL. As a result, as shown in FIG.
The condition necessary to develop a high adhesive force of 2.9 kgf / cord or more is the area% (S _4- ) of the polynuclear body of 4 or more nuclear bodies,
The ratio obtained by dividing the area% of the whole condensate (100 area%) by the area% (ΔS ₁ ) obtained by subtracting the area% (S ₁ ) of the mononuclear body [containing polynuclear bodies of 4 or more nuclides] Rate] is 60 to 73 area%, and the area% of the 4 to 6 nuclei (S _4-6 ) is calculated from the area% of the whole condensate (100 area%) to the area% of the mononuclear body (S ₁ ) Divided by the area% (ΔS ₂ ) obtained by subtracting
The content rate of the nuclear body] was 27 to 43 area%.

As described above, the 3,5-xylenol / resorcinol / formaldehyde condensation resin composition of the present invention having the content of each nuclide in the specific range is 2,6 in 3,5-xylenol methylol compound to be reacted with resorcin. -Dimethylol-
A 3,5-xylenol / resorcinol / formaldehyde condensation resin composition obtained so that the 3,5-xylenol concentration is 25% or more is preferable.

The reason for this condition is 2,6-dimethylol-
Since 3,5-xylenol is considered to react almost 100% in 3,5-xylenol-resorcinol-formaldehyde resin, nuclei derived from 3,5-xylenol in the condensation resin composition are almost the same% or more. This is because it is considered that they are methylene-bonded to resorcin at the 2- and 6-positions.

As a result, the adhesive obtained by mixing the 3,5-xylenol-resorcinol-formaldehyde condensation resin composition of the present invention and RFL stably exhibits a high adhesive force of 2.9 kgf / code or more.

Note that this is the relationship between the 2,6-dimethylol-3,5-xylenol concentration and the adhesive strength of the adhesive agent used by mixing the 3,5-xylenol / resorcin / formaldehyde condensation resin composition in RFL. This is based on the results of the research conducted by the authors as shown in FIG.
In this case, the area% (S _4-6 ) of 4 to 6 nuclides of the 3,5-xylenol-resorcinol-formaldehyde condensation resin composition used was calculated from the area% (100 area%) of the entire condensate. Area% obtained by subtracting area% (S ₁ ) of mononuclear body
The ratio [content of 4 to 6 nuclei] obtained by dividing by (ΔS ₂ ) is
It was 38 to 43 area%.

The 3,5-xylenol-resorcinol-formaldehyde condensation resin composition of the present invention as described above can be produced by the following method.

That is, 3,5-xylenol is methylolated with formaldehyde by a specific production method to obtain a 3,5-xylenol methylol compound, and the 3,5-xylenol methylol compound and resorcin are reacted in the presence of an acid catalyst. can get.

Here, first, the methylolation step of 3,5-xylenol will be described.

The methylolation step of 3,5-xylenol in the production method of the present invention is a reaction raw material of a 3,5-xylenol / resorcin / formaldehyde condensation resin composition 3,5-
It is intended to suppress the formation of condensates of xylenol methylol compounds and to form 3,5-xylenol methylol compounds (mononuclear compounds) in high yield. As a result, the content ratio of each nucleus of the 3,5-xylenol-resorcinol-formaldehyde condensation resin composition can be set within the above-mentioned constant range.

Furthermore, preferably, among various 3,5-xylenol methylol compounds produced, 2,6-dimethylol-3,5-
It is intended to highly selectively methylol 3,5 xylenol so that the content of xylenol is 25 area%. As a result, the resulting condensation product of the 3,5-xylenol methylol compound and resorcin can stably exhibit a high adhesive force of 2.9 kgf / code or more.

Based on the above intention, methylolation of 3,5-xylenol is carried out by adding 3,5-xylenol and formaldehyde or a formaldehyde-generating compound in an amount of 0.5 to 1.5 equivalents of the base, methylol, to 3,5-xylenol. The reaction is carried out in the presence of an organic solvent capable of dissolving the 3,5-xylenol methylol compound produced by the oxidization step and water. Here, the formaldehyde-generating compound means a compound capable of generating formaldehyde in the reaction system of 3,5-xylenol methylolation, and specific examples thereof include formaldehyde condensates such as paraformaldehyde and trioxane.

Thus, by performing methylolation of 3,5-xylenol in the presence of an organic solvent and water capable of dissolving the 3,5-xylenol methylol compound to be produced, the condensation reaction of the methylol compound is significantly suppressed, and 80 A mononuclear methylol compound can be obtained in a high yield of at least%.

As in the past, when 3,5-xylenol was reacted with formaldehyde in a water solvent in the presence of a small amount of a base catalyst to form a methyl roll, the resulting methylol compound contained a large amount of methylol compound condensate. Therefore, it is almost impossible to obtain the target mononuclear methylol compound in a high yield of 80% or more.

Specific examples of the organic solvent capable of dissolving the 3,5-xylenol methylol compound include cyclic ethers such as tetrahydrofuran and dioxane, and alcohols such as n-butyl alcohol. Among them, tetrahydrofuran is preferable. Also, such an organic solvent is preferably used in a molar ratio of 3,5-xylenol of about 0.5 mol or more, more preferably about 2.5 or more. This is because the use in this range can further suppress the formation of a condensate of methylol compounds.

The amount of water used is preferably 15 or less in terms of molar ratio to 3,5-xylenol. By adjusting the amount used in this range, the above-mentioned 2,6-dimethylol-
Highly selective production of 3,5-xylenol is possible. This is based on the following findings by the present inventors. That is, by changing the molar ratio of water to 3,5-xylenol, the production ratio of each methylol compound other than the 2,4,6-trimethylol compound can be significantly changed. Specifically, when water is used at various molar ratios with respect to 3,5-xylenol, the production ratio of each methylol compound is 2,3,6-trimethylol compound from 2 to 3 throughout.
On the other hand, when the molar ratio of water is 15 or less, the 4-methylol body and the 2,4-dimethylol body are a few% each, and the rest are mostly the 2-methylol body and the 2,6-dimethylol body. However, these relationships are reversed at a molar ratio of 15 or more. Therefore, it is preferable to maintain the molar ratio of water to 15 or less in order to increase the 2,6-dimethylol compound, which is an active ingredient of adhesive synthesis.

The type of base used in the present invention is not particularly limited as long as it is an alkali metal hydroxide or an alkaline earth metal hydroxide, but sodium hydroxide is particularly preferable.
However, the amount of base used is an important constituent factor of the present invention,
It is used in 0.5 to 1.5 equivalents based on 3,5-xylenol.

The amount of formaldehyde or the formaldehyde-generating compound used is preferably 0.5 to 3, more preferably 1.5 to 3, in terms of formaldehyde in terms of the number of moles with respect to 3,5-xylenol. Thereby, among the various methylol compounds produced, the above-mentioned 2,6-dimethylol-3,5
-Xylenol can be produced with high selectivity.

Methylolation of 3,5-xylenol using the above-described one is carried out in a mixture of 3,5-xylenol dissolved in the above organic solvent and an aqueous solution of a base at about 5 to 100 ° C., preferably about 20 to It can be carried out by adding formaldehyde dropwise under the temperature condition of 70 ° C. The total time of the dropping time and the reaction time after the dropping is about 1 to 20 hours, preferably 2
~ 10 hours.

After completion of the reaction, various acids such as acetic acid, formic acid, hydrochloric acid and phosphoric acid are added to the reaction mixture for neutralization and oil-water separation is performed to obtain a 3,5-xylenol methylol compound as an organic solvent liquid. The organic solvent solution of the 3,5-xylenol methylol compound is used in the subsequent condensation reaction step with resorcin.

Next, the condensation reaction step of the 3,5-xylenol methylol compound and resorcin will be described.

This condensation reaction is performed by reacting the 3,5-xylenol methylol compound obtained by methylolation of 3,5-xylenol described above with resorcin in the presence of an acid catalyst.

Specifically, a solution prepared by dissolving an acid catalyst and resorcin in an organic solvent or water similar to that used when synthesizing the 3,5-xylenol methylol compound is prepared, and in the solution, the 3, The target 3,5-xylenol / resorcinol / formaldehyde condensation resin composition can be obtained by dropping a solution of the 3,5-xylenol methylol compound synthesized in the methylolation step of 5-xylenol in an organic solvent.

Here, the amount of resorcin used is preferably set in the range of 1 to 5, particularly 1.5 to 3.0 as the reaction molar ratio to the 3,5-xylenol methylol compound. This makes it possible to easily control the proportions of various polynuclear bodies in the resulting condensate to fall within the range necessary for exhibiting the above-mentioned high adhesive strength. That is, when the amount of resorcin used is within the above range, the area% (S _4- ) of polynuclear bodies having 4 or more nuclides in the resulting condensate is
The ratio obtained by dividing the area percentage (S ₁ ) of the mononuclear body (S ₁ ) by the area percentage (△ S ₁ ) obtained from (100 area%) is 60 to 73 areas. %, And the area% obtained by subtracting the area% of the mononuclear body (S ₁ ) from the area% of the entire condensate (100 area%), and the area% of the 4 to 6 nuclear bodies (S _4-6 ).
The ratio [content of 4 to 6 nuclei] obtained by dividing by (ΔS ₂ ) is
It can be 27-43 area%.

As the acid catalyst used for the condensation reaction, known catalysts can be used, and specifically, hydrochloric acid, nitric acid, formic acid, acetic acid, oxalic acid, p-toluenesulfonic acid and the like can be used.

The amount used is about 0.1 with respect to 3,5-xylenol.
It is preferably in the range of -10 mol%, particularly 0.1-5 mol%.

The temperature of the condensation reaction is 10 to 100 ° C, preferably 30 to 80 ° C. However, this temperature is appropriately selected depending on the combination of the organic solvent used, the amount of catalyst, and the reaction time.

After completion of the condensation reaction, it is preferable to neutralize with an alkali from the viewpoint of preventing alteration of the co-condensation resin composition, but when the amount of the acid catalyst used is small, the acid catalyst is not neutralized and is left in the produced resin. You can leave it.

When neutralized with an alkali, the alkali is added to the resin produced as an aqueous solution. After neutralization, separate oil and water,
Then, the aqueous phase containing salts may be removed, and the oil phase may be concentrated to obtain a condensed resin composition, or the oil and water may not be separated, and the organic solvent and water may be concentrated directly to remove the salts. May remain in the condensation resin composition.

In addition, the content of unreacted monomer in the resin produced is 10
When it exceeds the area%, it should be 10 area% or less.
It is desirable to remove the unreacted monomer by washing with water after the above-mentioned alkali neutralization, or by distilling off the organic solvent from the separated oil phase and subsequently performing vacuum distillation.
Of course, if the monomer content in the condensed resin composition is 10% or less, such a removing operation is not necessary.

Thus, the condensed resin composition produced by the method of the present invention can be obtained as a solid after distilling off the organic solvent and water.

Next, a method of applying the 3,5-xylenol-resorcinol-formaldehyde condensation resin composition of the present invention to the adhesion between polyester fiber and rubber will be described.

The condensed resin composition of the present invention is not used by itself as an adhesive between polyester fiber and rubber, but is used as an adhesive by being used together with RFL which is well known as a vulcanizable adhesion aid. Before mixing with RFL, dilute with water before use. At that time, when the handling is difficult, the condensation resin composition of the present invention obtained as a solid may be dissolved in a lower alcohol such as methanol, ethanol or isopropyl alcohol before use. Further, since the condensed resin composition contains a component that is difficult to dissolve in neutral water, it may be dissolved in water using an alkali. As the alkali, alkali metal oxides such as sodium hydroxide and potassium hydroxide, ammonium hydroxide,
Organic amines such as monomethylamine can be used, of which ammonium hydroxide is particularly preferred. For those having poor solubility in alkaline water, they may be dispersed in water using a disperser such as a pole mill or a sand mill using any anionic surfactant.

By mixing the aqueous solution or aqueous dispersion of the condensation resin composition thus obtained with RFL, a one-pack type adhesive is formed.

The mixing ratio of the condensed resin composition and RFL is preferably 25: 100 to 125: 100 in terms of the ratio of each solid content.

The RFL used in the present invention may be one produced by a known preparation method. Specifically, the reaction molar ratio of resorcin and formaldehyde was set in the range of 1.0: 0.8 to 1: 7, and RF was produced by aging for several hours using an alkali catalyst such as sodium hydroxide or ammonium hydroxide. And rubber latex are mixed in the range of 1: 100 to 35: 100, and aged for several hours. Alternatively, resorcin, formaldehyde, and rubber latex may be mixed and aged at the above ratio from the beginning. The amount of alkali catalyst used is pH.
It is desirable to adjust so that the value is between 8.5 and 12.0.

As the rubber latex used for the RFL, at least one kind of synthetic rubber latex such as natural rubber latex, styrene-butadiene copolymer rubber terax, and styrene-vinylpyridine-butadiene copolymer rubber latex is used.

When using the adhesive configured as described above to bond the polyester fiber and the rubber, after first adhering the adhesive to the polyester fiber, at a temperature of 200 ℃ or more, preferably 220 ℃ ~ 250 ℃ Heat-treated to prepare an adhesive-treated polyester fiber. Next, by vulcanizing the adhesive-treated polyester fiber and the vulcanizable unvulcanized rubber, the polyester fiber and the rubber can be firmly bonded.

<Example> Hereinafter, the 3,5-xylenol.
The resorcinol / formaldehyde condensation resin composition and a method for producing the same are specifically described, and an adhesive obtained by mixing the produced condensation resin composition of the present invention and RFL was used for bonding polyester fiber and rubber. The evaluation result of the adhesive strength in the case will be described. Further, in the text, "part" means "part by weight" unless otherwise specified.

(Example 1) Production and evaluation of 3,5-xylenol / resorcinol / formaldehyde condensation resin composition (i) Methylolation reaction step of 3,5-xylenol A reflux condenser, a dropping funnel, a thermometer, and a stirrer were attached. A separable flask was charged with 0.556 parts of tetrahydrofuran and 0.339 parts of 3,5-xylenol and kept at 25 to 30 ° C. To this, a sodium hydroxide aqueous solution consisting of 0.115 parts of sodium hydroxide and 0.125 parts of water was added from a dropping funnel at a reaction temperature of 25 to 30.
The solution was added dropwise while being externally cooled so as to keep the temperature at ℃.

The dropping time was about 10 minutes. Subsequently, 0.451 parts of 37% aqueous formaldehyde solution was added dropwise, and the post-reaction was carried out for about 4 hours while maintaining the reaction temperature at 25 to 30 ° C.

Then, 0.167 parts of acetic acid was added to neutralize the reaction solution, and then 0.278 parts of tetrahydrofuran and 0.278 parts of water were added. After stirring, the mixture was left standing and oil-water separation was performed. After extracting 0.859 parts of the aqueous phase (including 0.236 parts of sodium acetate) as waste water, 1.45 parts (0.834 parts of tetrahydrofuran, 0.114 parts of water,
An oil phase of 0.52 parts of the methylolation product of 3,5-xylenol was obtained.

The composition of the methylolated product was measured by liquid chromatogram (column; Zorbax ODS 4.6 mm x 25 cm, developing solution; water / acetonitrile mixed solution, detector; UV254 nm). As a result, monomethylol 33%, 2,6-dimethylol The content was 27% in body, 3% in trimethylol body, and 5% in 3,5-xylenol (all are area%).

(Ii) Condensation reaction step of 3,5-xylenol methylol compound and resorcinol Resorcinol 0.576 parts, water 1.25 parts, oxalic acid dihydrate in a separable flask equipped with a reflux condenser, a dropping funnel, a thermometer and a stirrer. 0.012 parts were charged and heated to 50 ° C.

To this, 1.45 parts of a tetrahydrofuran solution of the 3,5-xylenol methylol compound produced in the methylolation step was added dropwise from a dropping funnel over 90 minutes. Continue to 60 ℃
The post-reaction was continued for 5 hours. Then sodium carbonate
An aqueous solution containing 0.010 part and 0.135 part of water was added to neutralize oxalic acid.

Then, without separation of oil and water, under reduced pressure of 10 to 20 mmHg, 1.5 parts of water at 80 ° C., 0.834 parts of tetrahydrofuran, and 2.43 parts of a light boiling fraction consisting of 0.096 parts of other components were removed,
1.00 parts of the target 3,5-xylenol / resorcin / formaldehyde resin was obtained.

The melting point of this resin is 82 to 134 ° C., and the result of GPC analysis (column: Toyo Soda's G3000HXL and G2000HXL directly connected, solvent: tetrahydrofuran 0.4 ml / min, detector: Shoden's differential refractometer SE-31), Monomer 16%, dinuclear 14%, trinuclear
It was 11%, 59% or more than tetranuclear bodies. The content of majority nuclei of 4 or more nuclei excluding the monomer components was calculated based on the formula to be 71%, and the content of 4 to 6 nuclei was calculated to be 33% based on the formula. All GPC compositions are area%.

(Iii) Manufacture of adhesive 15 parts of the solid content of 3,5-xylenol-resorcinol-formaldehyde resin manufactured by the above method were sampled and
% Ammonia water 10.5 parts was added, and water was added so that the total amount became 100 parts to obtain an aqueous ammonia solution of 3,5-xylenol / resorcin / formaldehyde resin.

An adhesive was prepared by mixing 75 parts of this aqueous ammonia solution and 100 parts of RFL. The RFL was prepared to have the following composition, and 48
It is aged over time. RFL water 518.8 parts Resorcin 11.0 parts Formaldehyde (37%) 16.2 parts Ammonium hydroxide (28%) 10.0 parts Vinyl pyridine-styrene- butadiene copolymer rubber latex (41%) 244.0 parts (iv) Adhesion evaluation Next polyester As the fiber, a polyethylene terephthalate tire cord having a twist structure of 1500 d / 2, an upper twist number of 40 times / 10 cm, and a lower twist number of 40 times / 10 cm is dipped in the above adhesive, and then 1.
After drying for 5 minutes, heat treatment was performed for 2 minutes in an air atmosphere kept at 240 ° C. to produce an adhesive treatment cord.

In adhering this adhesive treatment cord and the compounded rubber of the following composition, first, embed the adhesive treatment code in the unvulcanized state of the above compounded rubber, and then 145 ° C × 30 minutes, 2 kg
It was vulcanized under a pressure of f / cm ² . Compounded rubber composition Natural rubber 80 parts Styrene butadiene copolymer rubber 20 parts Carbon black 40 parts Stearic acid 2 parts Petroleum softener 10 parts Baintar 4 parts Zinc white 5 parts N-phenyl-β-naphthylamine 1.5 parts 2-Benzothiazolyl Disulfide 0.75 parts Diphenylguanidine 0.75 parts Sulfur 2.5 parts Adhesion was evaluated by digging up the cord from the vulcanizate thus obtained, peeling the cord from the vulcanizate at a speed of 30 cm / min, and measuring the peel resistance. This was done by setting this as an adhesive force.

The unit is kgf / code.

As a result, the 3,5-xylenol
Adhesive strength of resorcin / formaldehyde resin is 2.92kgf /
It was a code.

(Comparative Example 1) Production and evaluation of 3,5-xylenol / resorcinol / formaldehyde resin 3,5-xylenol 91.5 parts and water 12 in a separable flask equipped with a reflux condenser, a thermometer, a dropping funnel and a stirrer.
7.3 parts and 1.5 parts of sodium hydroxide were charged, and 121.6 parts of 37% aqueous formaldehyde solution was added dropwise thereto over 3 hours while maintaining the reaction temperature at 50 ° C.

Furthermore, after carrying out a post-reaction at the same temperature for 1 hour, it was cooled to 25 ° C., 93.7 parts of ethanol was added, and 432.6 parts of uniform 3,5
-A xylenol formalin reaction solution was obtained.

At this stage, the composition of the methylol compound was measured according to the analytical method shown in Example 1. As a result, the methylol compound of various mononuclear compounds contained only 30% or more, and most of the rest were the same as those of the methylol compound. It was a condensate. Also, 2-
Methylol body concentration is 6%, 4-methylol body concentration is 4
%, 2,6-dimethylol body concentration was 5% (all are area%).

In a separate separable flask, 165.0 parts resorcin, 24 water
Charge 7.3 parts and 4.2 parts of oxalic acid, stir at 70 ° C,
432.6 parts of the 3,5-xylenol / holimarin reaction solution was added dropwise over 3 hours. Then, post-reaction 3 at the same temperature
After that, 563.4 parts of a mixture of water and ethanol was distilled off at 70 to 149 ° C. under normal pressure. Subsequently, 31.5 parts of a mixture of unreacted 3,5-xylenol and resorcin was distilled off at 144 to 150 ° C. under a reduced pressure of 9 to 10 mmHg to obtain 246.5 parts of 3,5-xylenol / resorcinol / formaldehyde resin.

The weight average molecular weight of this resin (in terms of polystyrene) is 13
It was from 00 to 1400. Also, the area% of polynuclear bodies of 4 or more nuclear bodies
The (S _4-), the area% of the total the fused polymer (100 area%) from the area% of the mononuclear body (S ₁₎ and subtracted by comprising area% (△ S ₁₎ the ratio obtained by dividing the [4 Polynuclear body content above nucleolus] is about 90
%, Area% of 4 to 6 nuclei (S _4-6 ), area% of the whole condensate (100 area%) minus area% of mononuclear body (S ₁ ) (ΔS _The ratio [content of 4 to 6 nuclei] obtained by dividing by ₂ ) was about 20%. The adhesive strength of this resin was measured according to the method described in Example 1, and as a result, it was about 2.0 kg / cord.

(V) Adhesion deterioration test The 3,5-xylenol resorcin resin of Example 1 was used for 120
An adhesion deterioration accelerating test was conducted by exposing it to a nitrogen atmosphere at 0 ° C. for 3 days. As a result, in the case of the epoxy-treated two-component adhesive described in JP-B-39-10514, the initial adhesive strength was 2.
The value of 9 kg / cord decreased to 0.5 kg, but in the case of the resin of the present invention, a high adhesive force of 1.8 kg / cord was maintained.

In the case of the 3,5-xylenol-resorcinol resin of Comparative Example 1, the adhesive strength was reduced to 0.7 kg / cord after 3 days in the adhesion deterioration test under the same conditions.

<Effect of the Invention> The 3,5-xylenol-resorcinol-formaldehyde condensation resin composition of the present invention has an area% of tetranuclear or more polynuclear bodies of 3,5-xylenol-resorcinol-formaldehyde condensate contained therein ( the S _4-), the fused polymer entire area% (100 area%) from the area% of the mononuclear body (S ₁₎ and subtracted by comprising area% (△ S ₁₎ obtained by dividing the ratio [4 nuclei Polynuclear body content of the body or more] is 60 to 73 area%, and the area% of 4 to 6 cores (S _4-6 ) is calculated from the area% (100 area%) of the entire condensate to mononuclear body. Area% obtained by subtracting the area% (S ₁ ) of
The ratio [content of 4 to 6 nuclei] obtained by dividing by (ΔS ₂ ) is
Since it is 27 to 43 area%, the condensed resin composition of the present invention can be effectively diffused into the polyester fiber.

Accordingly, the 3,5-xylenol resorcin.
By using the formaldehyde condensation resin composition as an adhesion aid and forming an adhesive by mixing it with RFL, even if the adhesive is used for adhesion between polyester fiber and rubber, which have not been able to obtain high adhesion conventionally, High adhesive strength can be obtained. Further, it is possible to prevent the adhesion deterioration at a high temperature.

Further, since the 3,5-xylenol-resorcinol-formaldehyde condensation resin composition for adhesion aids of the present invention constitutes a one-pack type adhesive together with RFL, the polyester fiber adhesive treatment can be carried out in one step. The cost of bonding the rubber and the polyester fiber can be reduced. Further, no smoke is generated in the bonding process, and environmental pollution can be prevented.

And the 3,5-xylenol resorcinol of the present invention
According to the method for producing a formaldehyde condensation resin composition,
Since methylolation of 3,5-xylenol is carried out under specific reaction conditions, it can be carried out with high yield and high selectivity. Then, since the produced mononuclear body content is high and the 3,5-xylenol methylol compound and resorcin are condensed under a specific reaction condition, the present invention having the above-mentioned advantages 3,5-
A xylenol / resorcin / formaldehyde condensation resin composition can be easily produced.

[Brief description of drawings]

FIG. 1 (a) is a graph showing the relationship between the content of 1 to 3 nuclei and the adhesive force. Fig. 1 (b): Relationship between polynuclear body content of 4 or more nuclei and adhesive strength: Relationship between polynuclear body content of 4 or more nuclei and 4 to 6 nuclides: Polynuclear body of 4 or more nuclei It is a graph showing the relationship between the body content rate and the content rate of 7 or more nuclides. FIG. 2 is a multiple correlation analysis diagram showing the relationship between the polynuclear body content of 4 or more nuclei and the content of 4 to 6 nuclei and the adhesive force. FIG. 3 is a graph showing the relationship between the 2,6-dimethylol-3,5-xylenol concentration and the adhesive strength.

Claims (6)

(57) [Claims] 1. A compound represented by the following formula (a) in a 3,5-xylenol-resorcinol-formaldehyde condensation resin composition:
For the 3,5-xylenol-resorcinol-formaldehyde condensate, the area% (S _4- ) of the polynuclear body having four or more nuclides in which n is 2 or more in the formula (a) is the area% of the whole condensate ( The ratio [content of polynuclear bodies of 4 or more nuclei] is 60 to 73 area%, which is obtained by dividing the area% (S ₁ ) of mononuclear bodies by the area% (△ S ₁ ) And the area% of 4-6 nuclides in which n is 2-4 in the formula (a).
The ratio obtained by dividing (S _4-6 ) by the area% (ΔS ₂ ) obtained by subtracting the area% (S ₁ ) of the mononuclear body from the area% of the entire condensate (100 area%). 4-6 core content] is 27-43 area%, and a rubber and fiber having excellent high-temperature resistance, which contains RFL and an adhesion aid composed of a 3,5-xylenol-resorcinol-formaldehyde condensation resin composition And a one-component adhesive. 2. A 3,5-xylenol and formaldehyde or a formaldehyde generating compound, 0.5 to 1.5 equivalents of a base with respect to 3,5-xylenol, an organic solvent capable of dissolving a 3,5-xylenol methylol compound and water. Of the 3,5-xylenol methylol compound formed by reacting in the presence, 3,5-xylenol is methylolated so that the content of 2,6-dimethylol-3,5-xylenol is 25 area% or more, The 3,5-xylenol methylol compound and resorcin are reacted in the presence of an acid catalyst to produce an adhesion aid composed of a 3,5-xylenol / resorcinol / formaldehyde condensation resin composition, which is mixed with RFL. A method for producing a one-pack type adhesive containing rubber and fibers, which has excellent high temperature resistance. 3. The method according to claim 2, wherein the organic solvent capable of dissolving the 3,5-xylenol methylol compound is 0.5 mol or more with respect to the 3,5-xylenol.
Liquid adhesive manufacturing method. 4. The method for producing a one-pack adhesive according to claim 2 or 3, wherein the water has a molar ratio to the 3,5-xylenol of 15 or less. 5. The one liquid according to any one of claims 2 to 4, wherein the formaldehyde or the formaldehyde-generating compound has a molar ratio in terms of formaldehyde to 3,5-xylenol of 0.5 to 3. Method for producing mold adhesive. 6. The method according to any one of claims 2 to 5, wherein the resorcinol has a molar ratio of 1 to 5 with respect to the 3,5-xylenol methylol compound.
Liquid adhesive manufacturing method.