JPH0873825A - Rubber-based adhesive composition - Google Patents

Abstract

PURPOSE: To obtain a rubber-based adhesive composition useful for adhering shoes, woodworks, building materials, etc., excellent in stability against coloring by heating, phase separation during preservation, etc., by containing a specific phenolic resin, a gum and a metal oxide. CONSTITUTION: This rubber-based adhesive composition preferably comprises (A) 40-100 pts.wt. of a phenolic resin (preferably having 70-100 deg.C softening temperature) having <=1 of Gardner color scale (in 50wt.% toluene solution) produced by heat reacting 1 mole alkylphenol or arylphenol with >=1 mole aldehyde in the presence of a basic alkali or alkaline-earth metal hydroxide, adding a polymeric phenol-based antioxidant (preferably having 3-4 benzene-rings and 500-1500 molecular weight) and a benzotriazole-based UV adsorber and condensing in an acidic condition, (B) 100 pts.wt. of a rubber and (C) 2-20 pts.wt. of a metal oxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber-based adhesive composition having excellent heat non-coloring property. Rubber-based adhesives are widely used as industrial adhesives, for example, for bonding shoes, woodworking, building materials, home appliances and the like.

[0002]

2. Description of the Related Art Conventionally, it has been known to add an alkylphenol resin to a rubber-based adhesive in order to improve heat resistance, adhesive strength, stickiness retention time and the like. In such a rubber-based adhesive, since the sticking-out adhesive is generated and it takes a lot of time for wiping, especially when the shoe skins are adhered to each other, transparency of the adhesive is required. Further, there is a demand for an adhesive whose protrusion does not become colored by heating. The conventional rubber-based adhesives to which an alkylphenol resin has been added can only obtain a pale yellow or yellow rubber-based adhesive due to the coloring of the alkylphenol resin. Tokusho Sho 6
In JP-A 1-212268, 1 mol or more of an aldehyde is heated and reacted with 1 mol of an alkylphenol or an arylphenol in the presence of a potassium compound that is basic in a rubber-based adhesive composition, and then acidified to cause a condensation reaction. A rubber-based adhesive composition containing a phenolic resin having a softening point of 70 to 100 ° C. and a metal oxide obtained by the above is shown, but this has a problem in heat non-coloring property.

[0003]

As a result of intensive studies, the present invention has solved these problems by using a specific antioxidant and an ultraviolet absorber in combination, and is colorless and transparent and is not colored by heating. And excellent properties as a rubber adhesive (adhesiveness, heat resistance, adhesive strength, etc.),
The present invention also provides a rubber-based adhesive composition that is excellent in phase separation during storage.

[0004]

According to the present invention, 1 mol or more of an aldehyde is heated and reacted with 1 mol of an alkylphenol or an arylphenol in the presence of a hydroxide of a basic alkali metal or alkaline earth metal, Then
Phenolic resin, rubber and metal oxide having Gardner color number (50 wt% toluene solution) 1 or less obtained by adding a polymer type phenolic antioxidant and a benzotriazole type ultraviolet absorber and conducting a condensation reaction under acidic conditions A rubber-based adhesive composition containing

The phenol resin of the present invention is produced, for example, as follows. First, 1 mol or more, preferably 1.5 to 3 mol, of an aldehyde relative to 1 mol of an alkylphenol or an arylphenol (hereinafter simply referred to as phenols), and an alkali metal or alkaline earth metal hydroxide is preferably used as described above. 0. 1 for 1 mol of phenols.
It is made basic by adding it in an amount of 01 to 0.5 mol, for example, 50
Addition reaction is carried out at -100 ° C for 1-10 hours. If the aldehyde content is less than 1 mol, the molecular weight of the resole does not increase sufficiently, and a phenol resin having good characteristics cannot be obtained. Then, the reaction system is made acidic (preferably pH 3 to 6) by adding 0.03 to 1 mol of an organic acid or an inorganic acid to 1 mol of the above-mentioned phenols, and then the resulting salt is filtered. The polymer type phenolic antioxidant and the benzotriazole type ultraviolet absorber are added immediately after removal by washing with water or without removing them, and the condensation reaction is allowed to proceed in the presence thereof.

The polymeric phenolic antioxidant is 0.1 to 10% by weight, particularly 1 to 5% by weight, based on the resin solid content of the phenolic resin obtained from the viewpoint that it is excellent in light color effect and heat non-coloring property. It is preferable to add it. The benzotriazole-based UV absorber is less likely to cause turbidity, and is excellent in a light color effect and a heat non-coloring property, and therefore 0.01 to 10% by weight, particularly 0.1 to 0.1% by weight based on the resin solid content of the obtained phenol resin. It is preferable to add 1 to 1% by weight. The condensation reaction is
For example, it can be carried out by reacting at 80 to 180 ° C. for 5 minutes to 15 hours. The resulting phenol resin has a Gardner color number (50% by weight toluene solution) of 1 or less. When it exceeds 1, the heating non-coloring property is poor. It is preferable that the softening point of the phenol resin is 70 to 100 ° C. for convenience of mixing with other components. The phenol resin thus obtained is colorless and transparent, and is excellent in heat non-colorability and heat resistance.

Examples of the alkylphenol include cresol, amylphenol, tert-butylphenol, sec
-Butylphenol, octylphenol, nonylphenol, dodecylphenol and the like. Examples of the arylphenol include phenylphenol, substituted phenylphenol and cumylphenol. As the phenols, alkylphenols are preferable, and tert-butylphenol and octylphenol are particularly preferable.

As the aldehyde, formalin,
There are paraformaldehyde, furfural and the like, and formalin and paraformaldehyde are preferable. As the alkali metal or alkaline earth metal hydroxide, sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, barium hydroxide or the like is used, and potassium hydroxide, barium hydroxide or the like is preferable. Acids for acidifying the reaction system when adding the polymeric phenolic antioxidant and the benzotriazole ultraviolet absorber include hydrochloric acid, phosphoric acid, sulfuric acid and the like as inorganic acids, acetic acid as an organic acid, There are formic acid, oxalic acid, maleic acid, phthalic acid and the like, and among them, phosphoric acid and oxalic acid are preferable.

The polymeric phenolic antioxidants used in the present invention include 1,1,3-tris (2-methyl-
4-hydroxy-5-tert-butylphenyl) butane,
1,3,5-Trimethyl-2,4,6-tris (3,5
-Di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ', 5'-di-
tert-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3'-bis- (4'-hydroxy-3'-tert-butylphenyl) butyl acid]
Glycol ester, 1,3,5-tris (3 ', 5'
-Di-tert-butyl-4'-hydroxybenzyl) -s
-Triazine-2,4,6- (1H, 3H, 5H) trione, α-tocopherol, β-tocopherol, γ-
Tocopherol, δ-tocopherol and the like are used, but those having 3 or more benzene rings (preferably benzene ring having a hydroxyl group bonded), particularly 3 to 4 are preferable,
The molecular weight is 400 to 2000, especially 500 to 1.
It is preferably 500. Specifically, particularly preferred is 1,3,5-trimethyl-2,4,6-tris (3,5
-Di-tert-butyl-4-hydroxybenzyl) benzene.

The benzotriazole type ultraviolet absorber used in the present invention is 2- (2'-hydroxy-5'-).
Methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-te
rt-Butylphenyl) benzotriazole, 2- (2 '
-Hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-
Hydroxy-3 ', 5'-di-tert-butylphenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) -benzotriazole, 2- (2'-hydroxy-4'-octoxyphenyl) -benzotriazole , 2- (2'-
Hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl)
-Benzotriazole, 2,2-methylenebis [4-
(1,1,3,3-tetramethylbutyl) -6- (2H
-Benzotriazol-2-yl) phenol] and the like, and a benzotriazole derivative having a hydroxyphenyl group (a benzene ring to which a hydroxyl group is bonded) are used. Especially preferred is 2- (2'-hydroxy-5'-methylphenyl) benzotriazole.

By using the phenol resin obtained as described above, a rubber-based adhesive composition which is colorless and transparent and has excellent heat non-coloring property can be obtained. The rubber-based adhesive composition of the present invention contains rubber and a metal oxide together with the phenol resin. The rubber used in the present invention is generally one that can be used in rubber adhesives, and examples thereof include natural rubber, styrene-butadiene rubber, and acrylonitrile-
There are butadiene rubber, chloroprene rubber, recycled rubber, urethane rubber, epichlorohydrin rubber, and the like, and those modified with these are also included. Examples of the metal oxide used in the present invention include titanium oxide, magnesium oxide, zinc oxide and the like.

The ratio of the three components of the phenol resin, rubber and metal oxide is 40 to 1 of the phenol resin with respect to 100 parts by weight of the rubber in that excellent adhesive strength and heat resistance can be obtained.
It is preferable that the amount is 00 parts by weight and the metal oxide is 2 to 20 parts by weight. The rubber-based adhesive composition according to the present invention further includes a ketone resin, a coumarone / indene resin, a xylene resin, a petroleum resin, a terpene resin, a terpene phenol resin, a modifying resin such as an epoxy resin, calcium silicate, carbon black, Additives such as stearic acid, other antioxidants, vulcanization accelerators, curing agents and the like may be appropriately added, and organic solvents such as toluene, n-hexane, ethyl acetate and methyl ethyl ketone may be used.

The rubber-based adhesive composition is produced, for example, by roll kneading a rubber such as chloroprene rubber, a metal oxide such as magnesium oxide and zinc oxide, and an antioxidant such as Nocrac PA, if necessary, with toluene. It can be carried out by dissolving it in a mixed solvent such as to obtain a rubber liquid, and then adding and dissolving the phenol resin and the mixed solvent in the rubber liquid.

[0014]

EXAMPLES Next, examples of the present invention will be shown. Hereinafter, parts and% indicate parts by weight and% by weight, respectively. Example 1 A flask equipped with a stirrer, a reflux condenser, a thermometer, and an inert gas inlet was charged with p-tertiary-butylphenol 30.
0 g, formalin 324 g, and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, 2 g of acetic acid was added to confirm that the pH was 5.5, and then 0.2 g of phosphoric acid and an antioxidant (1,
3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene,
Product name ADEKA STAB AO-330, manufactured by Asahi Denka Co., Ltd. 3
g, UV absorber (2- (2'-hydroxy-5'-methylphenyl) benzotriazole, trade name Tinuvin-
P, manufactured by Geigy Co., Ltd.) 0.3 g, and added to 100 to 5
Curing was carried out at a system temperature of 110 ° C. at 00 mmHg to obtain a colorless and transparent phenol resin A having a Gardner color number (50% toluene solution) 1 (measured using a Gardner colorimeter) and a softening point of 80 ° C. 100 parts of polychloroprene (Neoprene AD, trade name of Showa Neoprene Co., Ltd.), 6 parts of magnesium oxide, 5 parts of zinc oxide, 2 parts of amine-based antioxidant (Nocrac PA, trade name of Ouchi Shinko Chemical Industry Co., Ltd.) Roll kneading, 113 parts of toluene, 113 parts of n-hexane and 11 parts of ethyl acetate
A rubber liquid was obtained by dissolving in a mixed solvent consisting of 3 parts. 45 parts of Resin A was dissolved in a mixed solvent of 45 parts of toluene, 45 parts of n-hexane and 45 parts of ethyl acetate, and then the above rubber liquid was mixed to obtain a rubber-based adhesive composition.

Comparative Example 1 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 373 g and barium hydroxide 6.3 g were charged and heated with stirring to react at 95 ° C. for 1 hour. After removing the separated water, 2 g of acetic acid was added and after confirming that the pH was 5.0, 0.2 g of 0.1% phosphoric acid was added,
Hardened at a system temperature of 130 ° C at 100-500 mmHg, Gardner color number (50% toluene solution) 2-3, softening point 115
Pale yellow transparent phenol resin B at ℃ was obtained. Resin B above
A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of

Example 2 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, 2 g of acetic acid was added to confirm that the pH was 5.8, and then 0.2 g of 0.1% phosphoric acid, 3 g of an antioxidant (Adeka Stab AO-330), an ultraviolet absorber (Tinuvin) were added. -P) 0.3 g was added and cured at 100 to 500 mmHg at an internal temperature of 110 ° C. to obtain a colorless and transparent phenol resin C having a Gardner color number (50% toluene solution) of 1 and a softening point of 85 ° C. A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of Resin C was used.

Example 3 In a flask equipped with a stirrer, a reflux condenser, a thermometer, and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, 2 g of acetic acid was added to confirm that the pH was 4.6, and then 0.2 g of 0.1% phosphoric acid, 1 g of an antioxidant (Adeka Stub AO-330), an ultraviolet absorber (Tinuvin- 0.1 g of P) was added and cured at 100 to 500 mmHg at an internal temperature of 110 ° C. to obtain a colorless and transparent phenol resin D having a Gardner color number (50% toluene solution) of 1 and a softening point of 86 ° C. A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of Resin D was used.

Comparative Example 2 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, 150% of 80% paraformaldehyde and 12 g of potassium hydroxide were charged and heated with stirring to react at 90 ° C. for 2 hours. After removing the separated water, add 90% acetic acid to 20
After adding g and confirming that the pH is 4.5, 100-5
It was cured at 00 mmHg at an internal temperature of 100 to 115 ° C. to obtain a pale yellow transparent phenol resin E having a Gardner color number (50% toluene solution) of 3 and a softening point of 110 ° C. Resin E above 45
A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that the same was used.

Example 4 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, adding 2 g of acetic acid and confirming that the pH was 5.0, 0.2 g of 0.1% phosphoric acid, 30 g of antioxidant (Adeka Stab AO-330), ultraviolet absorber (Tinuvin) -P) Add 3.0 g, 100-500 mm
Cured with Hg at an internal temperature of 110 ℃, Gardner color number (50
% Toluene solution) 1, and a colorless and transparent phenol resin F having a softening point of 90 ° C. was obtained. A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of the resin F was used.

Example 5 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, 2 g of acetic acid was added to confirm that the pH was 4.7, and then 0.2 g of 0.1% phosphoric acid, 6 g of an antioxidant (Adeka Stab AO-330), an ultraviolet absorber (Tinuvin) were added. -P) 0.1 g was added and cured at 100 to 500 mmHg at an internal temperature of 110 ° C. to obtain a colorless and transparent phenol resin G having a Gardner color number (50% toluene solution) of 1 and a softening point of 91 ° C. A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of Resin G was used.

Example 6 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, 2 g of acetic acid was added to confirm that the pH was 4.8, and then 0.2 g of 0.1% phosphoric acid, 6 g of an antioxidant (Adeka Stab AO-330), an ultraviolet absorber (Tinuvin) were added. -P) 0.6 g was added and cured at a system temperature of 110 ° C. at 100 to 500 mmHg to obtain a colorless and transparent phenol resin H having a Gardner color number (50% toluene solution) of 1 and a softening point of 81 ° C. A rubber adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of the above resin H was used.

Example 7 In a flask equipped with a stirrer, a reflux condenser, a thermometer and an inert gas inlet, p-tertiary-butylphenol 30 was added.
0 g, formalin 486 g and barium hydroxide 6 g were charged and heated with stirring to react at 95 ° C. for 2 hours.
After removing the separated water, adding 2 g of acetic acid and confirming that the pH was 4.3, 0.2 g of 0.1% phosphoric acid, 6 g of antioxidant (Adeka Stab AO-330), ultraviolet absorber (Tinuvin) -P) 1.2 g was added and cured at a system temperature of 110 ° C. at 100 to 500 mmHg to obtain a colorless and transparent phenol resin I having a Gardner color number (50% toluene solution) of 1 and a softening point of 83 ° C. A rubber-based adhesive composition was obtained in the same manner as in Example 1 except that 45 parts of Resin I was used.

The performances of the rubber-based adhesive compositions obtained in these examples and comparative examples are shown in Table 1.

[Table 1]

The test method is as follows. (1) Peel strength: Measured at a speed of 200 mm / min 5 days after adhesion with a stainless steel plate and a canvas by ASTM-D-903-49. (2) Heat resistance: Measured by ASTM-D-15-88-T3A on the third day after the adherends were adhered to each other. (3) Tack time: The adhesive composition is applied to art paper in advance with an applicator to a thickness of 0.5 mm and left at 25 ° C. for 20 hours. Next, the adhesive composition was similarly applied to the iron plate, and the adhesive composition surface of the art paper, which was cut into tanzaque shapes every 5 minutes, with 0 minutes as this time, was pressure-bonded to the adhesive composition surface of the iron plate with finger pressure immediately. Peel off. The time from 0 minutes until no adhesion was expressed as tack time. (4) Phase separation property: 20 g of the adhesive composition was weighed in an 18φ test tube, and the state after standing at 25 ° C. for 30 days was examined. (5) Non-coloring property by heating: An adhesive composition is applied to a glass plate to a thickness of 0.5 mm using an applicator and left at 80 ° C. for 7 days. The appearance of the adhesive composition after 7 days was expressed as non-colored by heating.

[0025]

EFFECT OF THE INVENTION The rubber-based adhesive composition of the present invention exhibits excellent adhesiveness and heat non-coloring property of the adhesive, and also has excellent adhesive strength and heat resistance, and also phase separation of the adhesive composition. Absent.
Therefore, it can be widely used as an adhesive composition for shoes, building materials, and home appliances.

Claims (4)

[Claims] 1. A polymer type phenolic antioxidant is prepared by reacting 1 mol or more of an aldehyde with 1 mol of an alkylphenol or arylphenol in the presence of a hydroxide of a basic alkali metal or alkaline earth metal, and then reacting with the polymer. Agent and benzotriazole type UV absorber are added,
A rubber-based adhesive composition containing a phenol resin having a Gardner color number (50% by weight toluene solution) of 1 or less, which is obtained by a condensation reaction under acidic conditions, a rubber, and a metal oxide. 2. The softening point of the phenol resin is 70 to 100.
The rubber-based adhesive composition according to claim 1, which has a temperature of ° C. 3. The content ratio of phenol resin, rubber and metal oxide is 4 parts by weight of phenol resin to 100 parts by weight of rubber.
The rubber-based adhesive composition according to claim 1 or 2, wherein the amount is 0 to 100 parts by weight and the metal oxide is 2 to 20 parts by weight. 4. The rubber-based adhesive composition according to claim 1, 2 or 3, wherein the polymeric phenolic antioxidant has 3 to 4 benzene rings and a molecular weight of 500 to 1500.