JP6084878B2 - Adhesive composition and product using the composition - Google Patents

Description

  The present invention relates to an adhesive composition and a product using the composition. More specifically, the present invention relates to providing an adhesive composition that is free from blisters during heat-drying treatment during production and has excellent viscosity stability, and has excellent adhesive strength and water resistance.

  Conventionally, a water-based adhesive composition in which an inorganic filler such as calcium carbonate is blended with a butadiene-based or acrylic synthetic emulsion is used for backing adhesives such as carpets and artificial grass, nonwoven fabric binders, and chipping paints. It is used. These adhesive compositions are applied to a substrate and then dried with a gas burner or high-temperature hot air to form a coating layer having a function for adjusting the adhesion function and texture or a substrate protection performance.

  In recent years, the number of cases where the speed of the coating machine is increased in order to pursue productivity, and measures such as increasing the temperature and increasing the air volume are taken as the drying process. However, when the water-based adhesive composition is rapidly heated and dried, phenomena such as blisters and cracks called so-called blisters are likely to occur, and when these phenomena occur, the productivity is remarkably reduced or the product quality is reduced. I had a problem.

  As a method for preventing blisters during the drying treatment, a method in which a polyorganosiloxane thermosensitive compound and a nonionic surfactant are used in combination as an additive (Patent Document 1: Japanese Patent Publication No. 56-44191), and the most common example. A method of adding starch (Patent Document 2: Japanese Patent Publication No. 57-30429) is known.

However, when using a polyorganosiloxane heat-sensitive compound, there is a concern that the adhesive composition gels during storage depending on the storage environment.
In addition, when starch is used, there is no concern about gelation, but there are problems that the adhesive strength and blister resistance decrease with time, and that the adhesive composition is easily spoiled.

  In addition, there is an example in which a nonionic surfactant and zirconium zirconium carbonate, which is a zirconium compound, are used in a carpet-based aqueous adhesive composition to prevent blistering (Patent Document 3: JP-A-3-23479). The performance balance such as long-term storage stability and fluidity of the agent composition is insufficient, and in order to compensate for this, a zirconium compound is added to the adhesive composition with a mixer provided immediately before the coating treatment step. There was a need. (Patent Document 4: Japanese Patent Application Laid-Open No. 2011-117112) However, complications are unavoidable due to an increase in the number of manufacturing steps, and there is a disadvantage that additional mixers cannot be installed depending on the structure of the coating machine.

Japanese Examined Patent Publication No. 56-44191

Japanese Patent Publication No.57-30429

Japanese Patent Laid-Open No. 3-23479

JP 2011-117112 A

  The purpose of the present invention is to solve the current problems in view of the above-mentioned circumstances, without generating blisters during the drying process during production, without increasing the viscosity stability, and without increasing the production process, The object is to provide processed products and coated products with excellent adhesive strength and water resistance.

In order to solve the above-described problems, an adhesive composition of the present invention is a backing adhesive composition containing a butadiene / styrene copolymer latex, and the sodium and potassium of the butadiene / styrene copolymer latex. The total content is 3500 ppm or less (based on 100 parts by weight of solid content) .
The backing adhesive composition of the present invention preferably further contains a nonionic surfactant having a cloud point in the range of 50 to 80 ° C.
Moreover, it is suitable that the adhesive composition for backing of the present invention further contains a polycarboxylate having a weight average molecular weight (Mw) of 20000 or less.
The product of the present invention is characterized by using the adhesive composition for backing of the present invention.

  The adhesive composition of the present invention is excellent in viscosity stability and blister resistance. A product using the adhesive composition of the present invention is excellent in adhesive strength and water resistance.

  The adhesive composition according to this embodiment contains a synthetic emulsion. Synthetic emulsions used in the adhesive composition of the present invention include, for example, butadiene / styrene copolymer latex, butadiene / acrylonitrile copolymer latex, butadiene / methyl methacrylate copolymer latex, butadiene / styrene / vinylpyridine copolymer. Synthetic rubber latex such as coalesced latex, polychloroprene latex, polyisoprene latex, for example, (meth) acrylate emulsion, vinyl acetate emulsion, urethane emulsion, vinyl chloride emulsion, vinylidene chloride emulsion, polyvinyl alcohol emulsion Synthetic resin emulsions such as these can be mentioned, and one or more of these can be used. Of these, butadiene / styrene copolymer latex is preferred.

The synthetic emulsion used in the adhesive composition of the present invention can be obtained by emulsion polymerization of each monomer. The addition method of various components in emulsion polymerization is not particularly limited, and any of a batch addition method, a divided addition method, a continuous addition method, and a power feed method can be employed. As the polymerization method, batch polymerization, semi-batch polymerization, seed polymerization and the like can be used.
Furthermore, in the case of emulsion polymerization, conventional emulsifiers, chain transfer agents, polymerization initiators, hydrocarbon solvents, electrolytes, polymerization accelerators, chelating agents, and the like can be used.

  The emulsifiers used in emulsion polymerization of synthetic emulsions include negative alcohol sulfates, alkylbenzene sulfonates, alkyl diphenyl ether disulfonates, aliphatic sulfonates, aliphatic carboxylates, sulfate esters and the like. 1 type or 2 types or more of amphoteric surfactants such as nonionic surfactants such as ionic surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkylene alkyl ethers, polyoxyethylene derivatives, and betaine types Can be used.

  Examples of chain transfer agents used in the synthetic emulsion include alkyl mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, t-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-stearyl mercaptan, dimethylxanthogen disulfide, Xanthogen compounds such as diisopropylxanthogen disulfide, terpinolene, thiuram compounds such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetramethylthiuram monosulfide, α-methylstyrene dimer, 2,6-di-t-butyl-4- Phenolic compounds such as methylphenol and styrenated phenol, allyl compounds such as allyl alcohol, dichloromethane, dibromomethane, carbon tetrabromide, etc. Rogenated hydrocarbon compounds, vinyl ethers such as α-benzyloxystyrene, α-benzyloxyacrylonitrile, α-benzyloxyacrylamide, triphenylethane, pentaphenylethane, acrolein, methacrolein, thioglycolic acid, thiomalic acid, 2-ethylhexyl A thioglycolate etc. are mentioned, These can be used 1 type or 2 or more types.

  As the polymerization initiator used in the synthetic emulsion, water-soluble polymerization initiators such as potassium persulfate, sodium persulfate, and ammonium persulfate, redox polymerization initiators, and oil-soluble polymerization initiators such as benzoyl peroxide may be appropriately used. it can. In particular, the use of a water-soluble polymerization initiator is preferred.

  Further, in the emulsion polymerization of the synthetic emulsion, saturated hydrocarbons such as pentane, hexane, heptane, octane, cyclohexane, cycloheptane, pentene, hexene, heptene, cyclopentene, cyclohexene, cycloheptene, 4-methylcyclohexene, 1-methylcyclohexene, etc. Hydrocarbon solvents such as unsaturated hydrocarbons, aromatic hydrocarbons such as benzene, toluene, and xylene may be used.

The synthetic emulsion used in the adhesive composition of the present invention needs to have a total content of sodium and potassium of 5000 ppm or less based on the solid content of the synthetic emulsion. When the total content of sodium and potassium exceeds 5000 ppm, the blister resistance in the drying process when obtaining a product using the adhesive composition of the present invention is reduced, or the adhesive strength and water resistance of the resulting product are reduced. Becomes worse. Preferably, it is 3500 ppm or less, more preferably 2500 ppm or less.
Sodium and potassium contained in the synthetic emulsion are brought in from polymerization aids such as a polymerization initiator, an emulsifier, an electrolyte, and a pH adjuster used in emulsion polymerization of the emulsion. As the polymerization aid, any of the above-mentioned known ones can be used in combination without any particular limitation. To make the total content of sodium and potassium in the finally obtained synthetic emulsion within the specified range of the present invention, It is necessary to adjust the type and amount of the above-mentioned polymerization aid. Specifically, for example, when sodium persulfate is used as a polymerization initiator, the amount of emulsifier, electrolyte and pH adjuster is reduced, or a type not containing sodium and potassium is used. By combining, it is possible to adjust within the scope of the present invention.
In addition, the total content of sodium and potassium in the synthetic emulsion is determined based on the alkali metal element by inductively coupled plasma emission spectroscopic analysis (ICP-AES: SPS4000 type manufactured by Seiko Denshi Kogyo Co., Ltd.) after thermally decomposing the synthetic emulsion with sulfuric acid and nitric acid. The amount of the alkali metal element obtained is calculated as the concentration (ppm) with respect to the solid content of the synthetic emulsion.

It is preferable that the adhesive composition of the present invention further contains a nonionic surfactant having a cloud point in the range of 50 to 80 ° C. Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylene alkyl ethers, polyoxyethylene derivatives, and the like, and one or more of these can be used. The addition amount of the nonionic surfactant is preferably 0.5 to 5.0 parts by weight with respect to 100 parts by weight of the synthetic emulsion. If the amount is less than 0.5 part by weight, the effect of improving the balance between viscosity stability and blister resistance is small, and if it exceeds 5.0 parts by weight, the adhesive strength and water resistance tend to decrease.
The nonionic surfactant is used when emulsion-polymerizing the synthetic emulsion, added to the synthetic emulsion obtained by emulsion polymerization, or directly added to the adhesive composition, Either is acceptable.
The cloud point of the nonionic surfactant is preferably in the range of 50 to 80 ° C. Although the cloud point is not limited to this range, it is effective for the viscosity stability of the composition. However, when the cloud point is in the range of 50 to 80 ° C., the effect on the function of preventing blistering is remarkable.

The adhesive composition of the present invention further preferably contains a polycarboxylate having a weight average molecular weight (Mw) of 20000 or less in terms of improving the blister resistance. Examples of polycarboxylic acid salts include polycarboxylic acid ammonium salts, polycarboxylic acid alkanolamine salts, polycarboxylic acid sodium salts, and the like, and one or more of these can be used. Of these, polyacrylate is preferable. The amount of polycarboxylate added is preferably 0.1 to 1.0 part by weight per 100 parts by weight of the synthetic emulsion. If it is less than 0.1 part by weight, the effect of improving the blister resistance is small. Moreover, even if it adds exceeding 1.0 weight part, the blister improvement effect corresponding to the addition amount is not acquired, and it is unpreferable.
The molecular weight of the polycarboxylate is preferably 20000 or less, more preferably 8000 or less in terms of weight average molecular weight. When the molecular weight of the polycarboxylate exceeds 20000, the viscosity at the time of blending the adhesive composition tends to increase, and the viscosity stability tends to decrease.
The polycarboxylate may be added to the synthetic emulsion obtained by emulsion polymerization, or may be added directly to the adhesive composition.

  In the adhesive composition of the present invention, one or more of calcium carbonate, clay, aluminum hydroxide, magnesium hydroxide, titanium oxide, barium sulfate and the like can be used as an inorganic filler. The amount of the inorganic filler used is preferably 100 to 500 parts by weight with respect to 100 parts by weight of the synthetic emulsion. If it is less than 200 parts by weight, the cost of the composition becomes high. If it exceeds 500 parts by weight, the adhesive strength tends to decrease.

  In the adhesive composition of the present invention, as other additives, anti-aging agent, ultraviolet absorber, flame retardant, preservative, deodorant, pH adjuster, thickener, foaming agent, antifoaming agent, filling Agents, dyes, pigments, fragrances and the like can also be added. Moreover, you may use together polyorganosiloxane and starch which have the function of preventing a blister.

  The product of the present invention can be obtained by applying the adhesive composition of the present invention to a substrate and drying it. The method for applying the adhesive composition is not particularly limited, and examples thereof include a roll coating method, a foam direct coating method, an impregnation method, and a spray method. The method for drying is not particularly limited, but a method of drying by heat treatment is preferred. The heating temperature at that time is preferably 80 to 160 ° C, more preferably 100 to 140 ° C.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to these Examples, unless the summary is exceeded. In the examples, parts and percentages indicating percentages are based on weight unless otherwise specified. In addition, various physical properties in the examples were evaluated by the following methods.

Evaluation of viscosity stability (Evaluation of viscosity stability over time)
After preparing the adhesive composition, the viscosity immediately after the preparation and the viscosity in a stationary state after being stored at 50 ° C. for 7 days were measured with a BM viscometer (No. 4 rotor, 12 rpm). The viscosity difference between the viscosity immediately after the preparation and the static viscosity over time was calculated, and the rate of change (%) of the viscosity difference with respect to the viscosity immediately after the preparation was calculated.
Change rate (%) = (Standing viscosity after storage at 50 ° C. for 7 days−Viscosity immediately after preparation) × 100 / Viscosity immediately after preparation From this change rate, the viscosity stability was evaluated as follows.
◎ (Viscosity stability is very good): Change rate is + 10% or less ○ (Viscosity stability is good): Change rate is more than + 10% and + 25% or less × (Viscosity stability is inferior): Change rate is + 25% Over

Evaluation of Blister Resistance An adhesive composition foamed twice with a hand mixer was applied to the back of a polyester tuft carpet base fabric at 900 g / m ² (wet), and then heated with a hot air dryer set at 200 ° C. Dry for 5 minutes.
Blisters such as blisters and cracks generated on the coated surface were visually evaluated from 5 points (excellent: no blisters were generated) to 1 point (poor: blisters were generated on the entire surface).

Evaluation of pulling-out strength It measured by the method based on JISL1021-8 (Fiber floor covering test method-Part 8: Pull-out strength test method of pile yarn).

Evaluation of water resistance The fiber-processed product was immersed in water at 25 ° C. for 1 hour, taken out, wiped off with a waste cloth, and then measured in the same manner as the evaluation of the yarn removal strength.

Preparation of synthetic emulsions A to D A pressure-resistant polymerization reactor was charged with 120 parts of pure water, 0.9 part of ammonium persulfate, and 0.3 part of sodium dodecylbenzenesulfonate, and after sufficient stirring, each unit shown in Table 1 was prepared. The polymer, 0.2 part of t-dodecyl mercaptan and 2 parts of cyclohexene were added and polymerization was started at 70 ° C., and the polymerization was terminated when the final polymerization conversion rate exceeded 95%.
Subsequently, the pH adjuster shown in Table 1 was added to the resulting synthetic emulsion, and unreacted monomers and other low-boiling compounds were removed by steam distillation to obtain synthetic emulsions A to D.

Preparation of synthetic emulsions E to G A pressure-resistant polymerization reactor was charged with 100 parts of pure water, 0.6 part of potassium persulfate, 0.1 part of sodium dodecylbenzenesulfonate, 0.5 part of sodium alkyldiphenyl ether disulfonate, After sufficiently stirring, each monomer shown in Table 1, 0.2 part of t-dodecyl mercaptan and 2 parts of cyclohexene were added and polymerization was started at 70 ° C. When the final polymerization conversion rate exceeded 95%. The polymerization was terminated.
Subsequently, the pH adjuster shown in Table 1 was added to the resulting synthetic emulsion, and unreacted monomers and other low-boiling compounds were removed by steam distillation to obtain synthetic emulsions E to G.

Preparation of adhesive composition (adhesive compositions 1-4, 13-15)
According to the coating formulation shown in Tables 2 and 3, 100 parts by weight of the synthetic emulsion, 400 parts by weight of calcium carbonate as the inorganic filler, 0.5 parts by weight of the foaming agent, and 2.5 parts by weight of the thickener And adhesive compositions 1 to 4 and 13 to 15 adjusted to a solid content of 70% using a predetermined amount of water.

Preparation of adhesive composition (adhesive compositions 5-8, 16)
Adhesive compositions 5 to 8 and 16 were obtained in the same manner as the adhesive composition 2 except that 1.0 part by weight of the nonionic surfactant shown in Tables 2 and 3 was added to the synthetic emulsion B. It was.

Preparation of adhesive composition (adhesive composition 9, 10, 12, 18)
Adhesive compositions 9, 10, 12, and 18 were obtained in the same manner as the adhesive composition 2 except that 0.5 parts by weight of the polycarboxylate shown in Table 3 was added to the synthetic emulsion B.

Preparation of adhesive composition (adhesive compositions 11, 17)
According to the coating formulation shown in Table 3, 100 parts by weight of synthetic emulsion, 400 parts by weight of calcium carbonate as inorganic filler, 0.5 parts by weight of foaming agent, 2.5 parts by weight of thickener, nonionic 1.0 parts by weight of a surfactant and 0.5 parts by weight of a polycarboxylate were blended to obtain adhesive compositions 11 and 17 adjusted to a solid content of 70% using a predetermined amount of water.

  In preparing the adhesive composition, as the nonionic surfactant, Emulgen 108, 120 (product name of Kao Corporation, Emulgen is a registered trademark of Kao Corporation), Neugen LF-80X, LF-100X (Product name of Daiichi Kogyo Seiyaku Co., Ltd., Neugen is a registered trademark of Daiichi Kogyo Seiyaku Co., Ltd.). As the polycarboxylate, Aron T-50 (product name of Toagosei Co., Ltd., Aron is a registered trademark of Toagosei Co., Ltd.), Socaran PA40, PA50 (product name of BASF) were used.

Fabrication of textile processed product Each adhesive composition obtained above was foamed to a foaming ratio of 2 times with a hand mixer, and 900 g / m ² (wet) was applied to the back of a polyester tuft carpet using a coating bar. After coating to an amount, it was dried at 140 ° C. for 15 minutes to obtain a fiber processed product.

  From the results of Table 3, since all the adhesive compositions 13 to 18 have a total content of sodium and potassium in the synthetic emulsion that exceeds the upper limit of the specified range of the present invention, the blister resistance of the fiber processed product, The unwinding strength and water resistance were greatly inferior.

  According to the adhesive composition of the present invention, since the viscosity stability is excellent, the workability in the step of applying the composition can be improved. Moreover, since it is excellent in blister resistance, it can withstand severer drying conditions in the drying process after coating, and productivity can be improved. In addition, by using the adhesive composition of the present invention, it is possible to stably provide processed products and coated products having excellent adhesive strength and water resistance. Therefore, backing adhesives such as carpets and artificial turf, nonwoven fabric binders, It can be suitably used for chipping paints.

Claims (4)

A backing adhesive composition containing a butadiene / styrene copolymer latex, wherein the total content of sodium and potassium in the butadiene / styrene copolymer latex is 3500 ppm or less (based on 100 parts by weight of solid content). It is characterized by being. Furthermore, the adhesive composition for backing of Claim 1 containing the nonionic surfactant which has a cloud point in the range of 50-80 degreeC. Furthermore, the adhesive composition for backing of Claim 1 or Claim 2 containing the polycarboxylate whose weight average molecular weight (Mw) is 20000 or less. The product using the adhesive composition for backing in any one of Claims 1-3.