JP5177681B2 - 2-Cyanoacrylate adhesive composition - Google Patents

Description

  The present invention relates to a 2-cyanoacrylate-based adhesive composition that retains excellent stability without impairing the curing rate even in a state of being in contact with air for a long time.

  The 2-cyanoacrylate adhesive has the advantage that it is a single solution and has a fast curing speed at room temperature, but it is weak against moisture and heat, so if it is in contact with air for a long time, it will depend on moisture in the air. The problem of thickening occurs such that the viscosity of the adhesive increases during storage and operation. In order to avoid this, there is a problem that the product life is shortened unless air is shielded from the adhesive as much as possible and the use and storage in a sealed state are not restricted.

Generally, as a method for applying 2-cyanoacrylate adhesive, an adhesive is filled in a sealed container such as a polyethylene bottle or an aluminum tube, and the adhesive is applied through a polyethylene or polypropylene nozzle attached to the container. A method of applying mechanically through a resin tube using a rotary type, pressure type dispenser or the like has been performed. In any case, until the adhesive is applied to the adherend, the stability of the adhesive itself is maintained by applying the adhesive so that it is not in contact with air as much as possible. However, in recent years, the application method of the 2-cyanoacrylate adhesive has also been diversified, and depending on the use and shape of the adherend, not only a conventional application method by dripping through a nozzle or resin tube, but also a brush or spatula.・ The application method using cotton swabs has been increasingly adopted. When adopting an application method using such a brush, spatula, cotton swab, etc., it is necessary to transfer the 2-cyanoacrylate adhesive to an open container such as a plate or tray. With cyanoacrylate adhesives, when the adhesive liquid surface is in contact with air over a long period of time using an open container, it cannot be applied due to rapid thickening, and the adhesive performance such as curing speed Inconveniences such as insufficient adhesion due to the decrease occurred.

So far, various stability-improved 2-cyanoacrylate adhesive compositions (Patent Documents 1 to 3) have been proposed. As a typical compound that has been used for these 2-cyanoacrylate adhesives, an example of a gaseous compound at room temperature is SO ₂ . Examples of the liquid compound at normal temperature include various inorganic acids and organic acids. However, because SO ₂ is a gas at room temperature, when added to a 2-cyanoacrylate adhesive that is liquid at room temperature, the SO ₂ is in the gas phase part of the void in the nozzle or in the sealed container due to diffusion to the gas phase part. Although the effect is recognized, the effect at the gas-liquid interface and the liquid phase part is small, and the duration of the effect is short, so it is necessary to use a relatively large amount, which is caused by a delay in curing speed or coloring It becomes a factor causing such problems.

  On the other hand, inorganic acids and organic acids that are liquid compounds at room temperature have an effect in the liquid phase part and contribute to the stability of the adhesive in a sealed container. In the state where the adhesive liquid surface is in contact with air for a long time, such as when the adhesive liquid is placed on an open dish or tray, the liquid surface of the adhesive is small. There was a problem that the thickening of the resin and the performance deterioration proceeded rapidly. Also, in combination with a gaseous compound, in order to increase the stability of the gas-liquid interface where the liquid surface of the adhesive is in contact with air, a relatively large amount must be used. Problems such as slowing of the curing speed and coloring have occurred, and no essential solution has been reached.

In recent years, as the market demands, the application method using brushes, spatulas, cotton swabs, etc., has been increasingly adopted for types with higher bonding speeds, and the curing speed is impaired even when in contact with air for a long time. Therefore, it has been desired to develop a 2-cyanoacrylate adhesive composition that retains excellent stability.

JP 58-63771 A JP-A-62-100568 JP 2002-285107 A

The present invention provides a 2-cyanoacrylate-based adhesive composition that maintains excellent stability without impairing the curing rate even in a state of being in contact with air for a long time.

In order to achieve the above object, the present inventors have earnestly studied various cyanoacrylate adhesive compositions that maintain a strong stability effect not only in the gas phase part and the liquid phase part but particularly in the gas-liquid interface. As a result of investigation, it was found that a specific compound having a vapor pressure in a specific range has a function of greatly enhancing the stabilization effect of the gas-liquid interface between the cyanoacrylate adhesive and air.
Furthermore, by combining with a specific stabilizer effective in the gas phase part and liquid phase part, the stability of the gas phase part in the nozzle or the resin tube and the stability of the liquid phase part when sealed in the container In addition, the present inventors have found that a strong stability effect appears at the gas-liquid interface when the liquid surface of the adhesive is in contact with air for a long time such as being placed in an open container such as a dish or tray. That is, a 2-cyanoacrylate-based adhesive composition comprising (A) 2-cyanoacrylate monomer and (B) acid gas, (C) HBF ₄ or BF ₃ complex salt, (D) sulfuric acid or p-toluenesulfonic acid By using a 2-cyanoacrylate-based adhesive composition characterized by containing 0.0001 to 0.01 part by weight per 100 parts by weight of 2-cyanoacrylate. The present invention was completed by finding that excellent stability was maintained without impairing the curing rate even in the state of being.

By using the 2-cyanoacrylate-based adhesive composition of the present invention, a 2-cyanoacrylate-based adhesive composition that retains excellent stability without impairing the curing speed even in a state of being in contact with air for a long time. Things can be provided.

Hereinafter, the present invention will be described together with embodiments.

Specific examples of (A) 2-cyanoacrylate in the present invention include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, octyl, neopentyl, cyclohexyl of 2-cyanoacrylic acid. , Ethylhexyl, dodecyl, allyl, methoxyethyl, ethoxyethyl, methoxypropyl, benzyl, phenyl, chloroethyl, tetrahydrofurfuryl and the like. Moreover, these (A) 2-cyanoacrylates can be used 1 type or in mixture of 2 or more types.

Examples of (B) acidic gas used in the present invention include SO ₂ , BF ₃ , HF, CO ₂ , NO, NO _{2 and the} like. Of _these, SO _{2, BF 3,} HF is preferred. Moreover, these (B) acidic gas can be used 1 type or in mixture of 2 or more types.

The amount of (B) acid gas used in the present invention is 0.0001 to 0.01 parts by weight, preferably 0.0002 to 0 parts per 100 parts by weight of (A) 2-cyanoacrylate. 0.005 part by weight. If it is less than 0.0001 part by weight, the duration of the effect as a stabilizer is short, and if it exceeds 0.01 part by weight, the curing rate is slowed or coloring is not preferred.

Examples of (C) HBF ₄ or BF ₃ complex salt used in the present invention include HBF ₄ , BF ₃ ether complex, and BF ₃ acetic acid complex. Of these, HBF ₄ is preferred. Moreover, these (C) can be used 1 type or in mixture of 2 or more types.

The amount of (C) HBF ₄ or BF ₃ complex salt used in the present invention is 0.0001 to 0.01 parts by weight, preferably 0, per 100 parts by weight of (A) 2-cyanoacrylate. 0.0001 to 0.005 parts by weight.
If it is less than 0.0001 part by weight, the duration of the effect of the stabilizer is short, and if it exceeds 0.01 part by weight, the curing rate is slowed or coloring is not preferred.

The amount of (D) sulfuric acid or p-toluenesulfonic acid used in the present invention is 0.0001 to 0.01 parts by weight, preferably 0.0001 to 0.00 parts per 100 parts by weight of 2-cyanoacrylate. 005 parts by weight. If it is less than 0.0001 part by weight, the effect of the stabilizer, particularly the duration of the effect on the liquid surface, is short, and if it exceeds 0.01 part by weight, the curing rate is slowed or coloring is not preferred.

A curing accelerator can be blended with the 2-cyanoacrylate adhesive of the present invention as long as the effects of the present invention are not inhibited.

Examples of the curing accelerator used as necessary in the present invention include (E) polyalkylene oxide derivatives and calixarene compounds.

（式中、Ｘ４ およびＸ５ は、それぞれ独立に水素原子、ハロゲン原子、水酸基、置換若しくは非置換のアルキル、アルケニル、アリール又はアラルキル基を示す。ｐは１以上の整数、ｑは２以上の整数を示し、末端は環形成されていてもよい。）
なる繰り返し単位を有する化合物から選ばれた１種以上が挙げられる。 In the present invention, among the (E) polyalkylene oxide derivatives and calixarene derivatives which are curing accelerators used as necessary, the polyalkylene oxide derivatives include those represented by the formula (3)

(Wherein X4 and X5 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a substituted or unsubstituted alkyl, alkenyl, aryl or aralkyl group. P is an integer of 1 or more, and q is an integer of 2 or more. And the terminal may be ring-formed.)
1 type or more chosen from the compound which has the repeating unit which becomes.

Specific examples of the polyalkylene oxide derivative include, but are not limited to, the following compounds.

  Formaldehyde condensate, acetaldehyde condensate, trioxane polymer, polyalkylene glycol (eg diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol (400, 1000, etc.), dipropylene glycol, polypropylene glycol, polytetramethylene oxide, poly 3,3-bis (chloromethyl) butylene oxide, poly 1,3-dioxolane, ethylene oxide-propylene oxide block polymer, etc.)

Polyalkylene glycol monoethers (eg methyl carbitol, carbitol, diethylene glycol-n-butyl ether, diethylene glycol phenyl ether, diethylene glycol benzyl ether, dipropylene glycol ethyl ether, tripropylene glycol methyl ether, polyethylene glycol methyl ether, polyethylene glycol propyl ether Polyethylene glycol lauryl ether, polyethylene glycol stearyl ether, polyoxyethylene nonylphenyl ether, polyethylene glycol allyl ether, etc.), polyalkylene glycol diethers (eg, diethylene glycol diethyl ether, diethylene glycol di-n-butyl ether, triethylene glycol) Lumpur dimethyl ether, tetraethylene glycol distearyl ether, polyethylene glycol dimethyl ether.

Polyalkylene glycol monoesters (eg, diethylene glycol monopropionate, tetraethylene glycol monoacetate, tripropylene glycol mono-n-butyrate, polyethylene glycol monoacetate, polyethylene glycol monopropionate, polyethylene glycol laurate, polyethylene glycol sebacate , Polyethylene glycol stearate, polyethylene glycol oleate, polyoxyethylene sorbitan monolaurate, diethylene glycol acrylate, diethylene glycol methacrylate, diethylene glycol crotonate, etc.), polyalkylene glycol diesters (eg, diethylene glycol diacetate, diethylene glycol dipropionate, die Lenglycol diacrylate, diethylene glycol distearate, diethylene glycol dimethacrylate, tetraethylene glycol dicrotonate, polyethylene glycol diacetate, polyethylene glycol di-n-butyrate, polyethylene glycol diurarate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, Polyethylene glycol dicrotonate, polyethylene glycol di-2-cyanoacrylate, polyethylene glycol stearyl-methacrylate, polyethylene glycol lauryl-acrylate, etc.),

Polyalkylene glycol monoether monoester (for example, methyl carbitol, carbitol, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, polyethylene glycol monomethyl ether, polyethylene glycol monoethyl ether, tetraoxyethylene glycol monomethyl ether, polyoxyethylene glycol monolauryl Ethers, acrylates, methacrylates, crotonates, or 2-cyanoacrylates of glycol monoether compounds such as polyoxyethylene glycol monononylphenyl ether), other bisphenol A-polyalkylene oxide adducts, trimethylolpropane-polyalkylene oxide additions Glycerin-polyalkylene oxide Addendum, adipic acid - polyalkylene oxide adducts, trimellitic acid - polyalkylene oxide adducts and the like. Other cyclic compounds include, for example, 18-crown-6-ether, 15-crown-5-ether, 18-crown-5-ether, dithio-15-crown ether, dibenzo-18-crown-6-ether, dicyclohexyl- 18-crown-6-ether, 1,2-naphth-15-crown-5-ether, 1,2-methylbenzo-18-crown-6-ether and the like can be used. Or you may use 2 or more types.

（式中、Ｒ４は水素原子、更に置換されていてもよいアルキル基および置換されていてもよいアルコキシ基であり、Ｒ５は水素原子又は置換されていてもよいアルキル基である。また、ｙは４，６又は８である。） As the calixarene compound, the following formula (4)

(Wherein R4 is a hydrogen atom, an optionally substituted alkyl group and an optionally substituted alkoxy group, R5 is a hydrogen atom or an optionally substituted alkyl group, and y is 4, 6 or 8.)

The calixarene compound shown by these is mention | raise | lifted. As such calixarene compounds, specifically, 5,11,17,23,29,35-hexa-tert-butyl-37,38,39,40,41,42-hexahydroxycalix [6 ] Allene, 37,38,39,40,41,42-hexahydroxycalix [6] allene, or 37,38,39,40,41,42 described in, for example, JP-A-60-179482 -Hexa- (2-ethoxy-2-oxoethoxy) -calix [6] allene, 25,26,27,28-tetra- (2-ethoxy-2-oxoethoxy) -calix [4] allene and the like are preferably used It is done.

In this invention, the usage-amount of the hardening accelerator used as needed is 0.005-5.0 weight part normally with respect to 100 weight part of 2-cyanoacrylate, Preferably it is 0.01-1.0. Parts by weight.

In addition, the 2-cyanoacrylate adhesive composition of the present invention includes a stabilizer (for example, hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, conventionally used by adding to a 2-cyanoacrylate adhesive). Radical polymerization inhibitors such as catechol and pyrogallol), plasticizers (dimethyl phthalate, diethyl phthalate, diisodecyl phthalate, etc.), thickeners (acrylic ester copolymer elastomer, styrene-butadiene copolymer elastomer, Polyurethane elastomers, chloroprene elastomers, carboxylated acrylonitrile-butadiene copolymer elastomers, polyester elastomers, fluorine elastomers, polyisoprene elastomers, epichlorohydrin elastomers, ethylene 2-propylene copolymer elastomers, ethylene-vinyl acetate copolymer elastomers), colorants, fragrances, solvents, strength improvers, aliphatic polycarboxylic acids, aromatic polycarboxylic acids, etc., depending on the purpose. As long as the stability of the acrylate monomer is not impaired, it can be added and blended as appropriate.
Hereinafter, the present invention will be described in more detail with reference to examples.

(Example)
The present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

〔Test method〕
Measurements and evaluations in the examples were performed according to the following methods.
<Stability test 1: Nozzle clogging resistance test>
An aluminum tube is filled with 3 g of the adhesive composition. Attach a cap to the polyethylene nozzle and the tip of the nozzle after opening. Next, about 10 cm is applied to a commercially available NBR test piece (1 × 25 × 100 mm manufactured by Engineering Test Service) while the tip of the nozzle is in contact therewith. The nozzle tip is covered with a cap and allowed to stand for 30 minutes, and then similarly applied onto NBR and the nozzle tip is covered with a cap. In this state, it was exposed to an atmosphere of 60 ° C. and 95% RH, and the number of days that the adhesive composition accumulated inside the nozzle was solidified and the adhesive was not released because the nozzle was blocked was measured. The longer the nozzle clogging days, the better the stability of the gas phase.
The nozzle clogging resistance was evaluated as follows according to the number of days until the nozzle was blocked. ○: 7 days or more, Δ: 4-6 days, ×: 3 days or less <Stability test 2: forced exposure test under high temperature and high humidity>
After filling 20 g of the adhesive composition into a polyethylene container (cylindrical container having an inner diameter of 25 mm and a height of 50 mm), it was sealed with a nozzle, and after curing in a 60 ° C. and 95% RH atmosphere for 7 days, the viscosity was JIS- Measurement was performed according to K6861. The smaller the increase in viscosity, the better the stability of the liquid phase part.
<Stability test 3: Long-term air exposure test>
Fill the polyethylene container (cylindrical container with an inner diameter of 15 mm x height of 8 mm) with 1 g of the adhesive composition for the purpose of reproducing the stability of the container in an open container during application with a brush or spatula, and then open it. The solution was allowed to stand in an atmosphere of 60 to 70% RH at 20 ° C., and the viscosity after 10 days was measured according to JIS-K6861. The smaller the increase in viscosity, the better the stability of the gas-liquid interface.
<Measurement of set time after long-term air exposure (measurement and evaluation of curing time)>
Curing time was measured using the adhesive subjected to the long-term air exposure test of Stability Test 3.
EPDM rubber and CR rubber were used as adherends, and measurements were taken according to JISK6861.

(A) 0.005 part by weight of SO ₂ , (C) 0.005 part by weight of HBF ₄ and (D) 0.0005 part by weight of sulfuric acid are added to 100 parts by weight of 2-ethylcyanoethyl acrylate. A 2-cyanoacrylate adhesive composition was prepared. Table 2 shows the stability test results 1 to 3 and the set time measurement results after long-term air exposure of the obtained adhesive composition.

(Examples 2-4, Comparative Examples 1-3)
A 2-ethylcyanoacrylate adhesive was prepared in the same manner as in Example 1 except that each component had the composition shown in Table 1. Table 2 shows the stability tests 1 to 3 and the set time measurement results after long-term air exposure for each of the obtained adhesive compositions.

Ｂ-1：ＳＯ_２
Ｃ-1：ＨＢＦ_４
Ｃ-2：ＢＦ_３ジエチルエーテル錯体
Ｄ-1：硫酸
Ｄ-2：パラトルエンスルホン酸
Ｅ-1：３７，３８，３９，４０，４１，４２−ヘキサ−（２−エトキシ−２−オキソエトキシ）−カリックス〔６〕アレン
Ｅ-2：ポリエチレングリコール＃４００モノメチルエーテルモノメタクリレート

B-1: SO ₂
C-1: HBF ₄
C-2: BF ₃ diethyl ether complex D-1: sulfuric acid D-2: p-toluenesulfonic acid E-1: 37, 38, 39, 40, 41, 42-hexa- (2-ethoxy-2-oxoethoxy) -Calix [6] Allene E-2: Polyethylene glycol # 400 monomethyl ether monomethacrylate

Claims (3)

A 2-cyanoacrylate adhesive composition comprising (A) 2-cyanoacrylate monomer and (B) acid gas, (C) HBF ₄ or BF ₃ complex salt, (D) sulfuric acid or p-toluenesulfonic acid, A 2-cyanoacrylate-based adhesive composition containing 0.0001 to 0.01 parts by weight per 100 parts by weight of 2-cyanoacrylate. (B) acid gas SO _2, BF _3, claim 1 of 2-cyanoacrylate-based adhesive composition, wherein the at least one compound selected from _HF. 2. The composition according to claim 1, wherein at least one compound selected from (E) a polyalkylene oxide derivative and a calixarene derivative is contained as a curing accelerator in an amount of 0.005 to 5 parts by weight based on 100 parts by weight of 2-cyanoacrylate. The 2-cyanoacrylate adhesive composition according to any one of?