JPH04220484A - Adhesive - Google Patents

Abstract

PURPOSE:To obtain an adhesive having a long and stable pot life and improved adhesive strength in a highhumidity atmosphere by mixing a vinyl acetate polymer with a higher alcohol and an organic solvent in a specified ratio. CONSTITUTION:An adhesive is obtained by mixing 100 pts.wt. vinyl acetate polymer (e.g. polyvinyl acetate) of a degree of polymerization of 200-10000 with 1-15 pts.wt. 5-28 C, desirably 16-18 C higher alcohol (e.g. 16 C alcohol) as a retarder, 10-2000 pts.wt. organic solvent (e.g. methanol), and optionally water, a filler, a plasticizer, another adhesive resin, a colorant, a fiber, a stabilizer, a surfactant, etc.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a solvent-based vinyl acetate adhesive that has a pot life that is not affected by the temperature during use and has excellent adhesive strength in high humidity environments. .

0002

[Prior Art] Conventionally, paste adhesives made by dissolving vinyl acetate polymers together with various fillers, additives, etc. in organic solvents such as methanol have been used for bonding vinyl chloride resin tiles, wooden tiles, etc. Widely used in various fields such as woodworking and paper. However, when this adhesive is applied to an adherend, since the solvent evaporates rapidly, a film is formed on the surface within several minutes after application, resulting in a decrease in adhesive properties. That is, it has short pot life and poor workability, which is a big problem especially when applying over a large area, and workability is significantly reduced at high temperatures.

[0003] For this reason, it has been proposed to add various surfactants to adhesives for the purpose of extending the pot life. In other words, Special Public Interest Publication in 1972-
43179 discloses the inclusion of an alkylamine, Japanese Patent Publication No. 49-23812 discloses the inclusion of a specific nonionic surfactant or anionic surfactant, and JP-A-53-67739 discloses the inclusion of a specific nonionic surfactant or anionic surfactant. It is also known that stearic acid ester or ethylene oxide adducts of glycerin/diglycerin may be contained, as disclosed in JP-A-56-269.
Publication No. 46 proposes the inclusion of a glycerin partial acetate monohigher fatty acid ester. However, although all of these proposals extend the pot life by adding these substances, the pot life varies greatly depending on the ambient temperature in which the adhesive is used. There are flaws in gender.

In addition, in JP-A No. 61-192776, in order to improve the above-mentioned drawbacks, the degree of saponification is further increased from 1 to 40 mol%.
It has been proposed to add low saponification polyvinyl acetate. However, although this method extends the pot life and improves its stability, it has the drawback of poor adhesive strength in a high humidity atmosphere.

[0005] In any of these cases, it is currently not possible to obtain an adhesive that satisfies all required performances.

[0006]

[Problems to be Solved by the Invention] As a result of intensive studies aimed at improving these drawbacks, the present inventors found that by incorporating a specific alcohol as a retardant into a vinyl acetate solvent-based adhesive, the adhesive can last for a long time. and has a stable pot life.
Furthermore, the present inventors have discovered that an adhesive with excellent adhesive strength even in a high humidity atmosphere can be obtained, leading to the completion of the present invention.

[0007]

[Means for Solving the Problems] That is, the present invention contains a vinyl acetate polymer, a higher alcohol, and an organic solvent,
The content of the higher alcohol is 100% of the vinyl acetate polymer.
The adhesive is characterized in that the amount is 1 to 15 parts by weight.

The present invention will be explained in detail below. As the vinyl acetate polymer used in the present invention, vinyl acetate polymers, vinyl acetate copolymers, modified products thereof, etc. can be used. For example, in addition to vinyl acetate homopolymers, vinyl acetate and (meth) Acrylic acid ester, olefins such as ethylene, propylene or higher α-olefins,
Polymerizable unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid, and maleic acid, or their alkyl esters, half esters, anhydrides, amides, nitriles, and salts, polymerizable unsaturated sulfonic acids or their salts, vinyl versatate ,
Copolymers with alkyl vinyl ethers, vinyl chloride, etc. are included. Among them, vinyl acetate homopolymer, vinyl acetate-(meth)acrylic acid ester, vinyl acetate-crotonic acid, vinyl acetate-olefin, vinyl acetate-acrylic acid, vinyl acetate-methacrylic acid, vinyl acetate-maleic acid, etc. It is preferable to use a copolymer as the vinyl acetate polymer. Moreover, the above-mentioned vinyl acetate polymers can be used alone or in combination of two or more.

The degree of polymerization of the vinyl acetate polymer used in the present invention is preferably from 200 to 10,000, preferably from 300 to 5,000.
is more preferable, and particularly preferably 500 to 2,500.

Furthermore, the vinyl acetate polymer used in the present invention can be used without being limited to the polymerization method used to obtain the polymer, such as solution polymerization, suspension polymerization, bulk polymerization,
Those obtained by emulsion polymerization etc. can be used.

In the present invention, the higher alcohol used as a retarder is preferably an alcohol having 5 to 28 carbon atoms, such as octyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, etc. Among these, higher alcohols mainly composed of alcohols having 16 to 18 carbon atoms are particularly preferred. Further, higher alcohols can be used alone or in combination of two or more.

[0012] The higher alcohol used in the present invention can be a saturated or/and unsaturated alcohol, and the presence or absence of a side chain is not limited. Furthermore, it is preferable to use higher alcohols obtained from animal and vegetable raw materials, such as coconut oil, whale oil, beef and pork fat, because they are easily available and inexpensive. The higher alcohol used in the present invention has 5 carbon atoms.
Although there is no problem even if a small amount of alcohol outside the range of 28 to 28 carbon atoms is contained, it is preferable that the alcohol outside the range of 5 to 28 carbon atoms is contained in an amount of 10% by weight or less.

The blending ratio of the higher alcohol in the adhesive of the present invention is preferably 1 to 15 parts by weight, preferably 2 to 10 parts by weight, based on 100 parts by weight of the vinyl acetate polymer. If it is less than 1 part by weight, it will not be effective in extending pot life, and if it exceeds 15 parts by weight, the adhesive strength will decrease.

The organic solvent used in the present invention is not particularly limited, and any organic solvent suitable for the vinyl acetate polymer used can be used. For example, for resins with a high proportion of vinyl acetate polymer units, industrial Methanol, which is easily available, is preferably used. In addition, organic solvents such as ethanol, toluene, acetone, and ethyl acetate can also be used. Further, the organic solvents may be used alone or in combination of two or more.

The content of the organic solvent contained in the adhesive of the present invention is appropriately selected depending on the workability, viscosity, etc. desired for the adhesive. Preferably 10 to 2000 parts by weight, more preferably 20 to 2000 parts by weight, particularly preferably 30 to 50 parts by weight.
0 parts by weight is desirable.

The adhesive of the present invention may contain water to the extent that its performance is not impaired. The adhesive of the present invention includes:
If desired, fillers such as calcium carbonate, asbestos, clay, kaolin, talc, powdered silica, titanium oxide, fly ash, rosin, rosin derivatives, plasticizers,
It may also contain resins with adhesive properties other than vinyl acetate polymers, organic or inorganic fibers, colorants, stabilizers, surfactants, etc.

The adhesive of the present invention comprises a vinyl acetate polymer,
It can be obtained by mixing a higher alcohol and an organic solvent, and optionally adding fillers, plasticizers, stabilizers, etc., and there are no restrictions on the manufacturing method.

When the vinyl acetate polymer is used in liquid form,
An organic solvent may be used as necessary during the above mixing. When the vinyl acetate polymer is in a solid state, the adhesive of the present invention can also be obtained by mixing the substances to be blended except for the organic solvent, and then mixing it with the organic solvent.

When it is desired to obtain an adhesive containing a filler by using both the vinyl acetate polymer and the higher alcohol in solid form, the polymer, the filler and the higher alcohol are mixed, and the resulting mixture is mixed. An adhesive can be obtained by mixing the adhesive with other substances such as an organic solvent. In this case, the mixture of the polymer, filler, and higher alcohol has the advantage of being easy to store, transport, package, etc., and difficult to block.

In order to obtain a homogeneous adhesive, it is preferable to mix a small amount of a substance such as a higher alcohol with the vinyl acetate polymer liquid, organic solvent, etc. used in advance.

[0021] The mixer used to obtain the adhesive of the present invention does not require a special one; a commonly used mixer equipped with an agitator can be used, and when the viscosity is high, a high viscosity mixer such as a planetary mixer can be used. , kneader, etc. can be used. Further, the temperature at the time of mixing is not particularly limited, but it is preferably below the boiling point of the organic solvent used. The adhesive of the present invention can be widely used for adhering vinyl chloride resin tiles, wooden tiles, etc., as well as wood, plywood, wood wool boards, paper, paperboard, fibers, cloth, nonwoven fabrics, etc. I can do it.

[0022]

EXAMPLES The present invention will be explained in detail with reference to Examples below. Example 1 100 parts by weight of polyvinyl acetate with a degree of polymerization of 1000, 140 parts by weight of methanol, 1 part by weight of calcium stearate, and 1 part by weight of higher alcohol A shown in Table 1 were charged into a mixer and stirred for about 1 hour. Next, 80 parts by weight of calcium carbonate and 80 parts by weight of asbestos were added, and the mixture was further stirred and kneaded for 1 hour to prepare an adhesive. As a result of measuring the pot life and adhesive strength of this adhesive according to Test Method I and Test Method II described later, it showed the characteristics as shown in Table 3, and was able to satisfy the performance as an adhesive.

Example 2 An adhesive was prepared in the same manner as in Example 1 except that the amount of higher alcohol A was changed to 3 parts by weight. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 3 100 parts by weight of granular polyvinyl acetate with a degree of polymerization of 1000,
1 part by weight of calcium stearate, higher alcohol A5
Important parts, 80 parts by weight of calcium carbonate and 80 parts by weight of asbestos
Parts by weight were dry blended using a mixer to obtain a mixture. Pack this mixture into bags and stack the bags 3 times.
Although the bag was left for a month, the mixture in the bag did not solidify into a block.

Next, 266 parts by weight of this mixture and 140 parts by weight of methanol were kneaded in a kneader to prepare an adhesive. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 4 An adhesive was prepared in the same manner as in Example 1, except that the amount of higher alcohol A in Example 1 was changed to 8 parts by weight, and the higher alcohol was mixed in advance with methanol before use. was created. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive. Example 5 An adhesive was produced in the same manner as in Example 1 except that the amount of higher alcohol A was changed to 10 parts by weight. As a result of evaluating this adhesive using the same method as in Example 1,
It exhibited the characteristics shown in Table 3, and was able to satisfy the performance as an adhesive.

Example 6 An adhesive was prepared in the same manner as in Example 1 except that the amount of higher alcohol A was changed to 12 parts by weight. As a result of evaluating this adhesive using the same method as in Example 1,
It exhibited the characteristics shown in Table 3, and was able to satisfy the performance as an adhesive.

Example 7 An adhesive was prepared in the same manner as in Example 1 except that the amount of higher alcohol A was changed to 14 parts by weight. As a result of evaluating this adhesive using the same method as in Example 1,
It exhibited the characteristics shown in Table 3, and was able to satisfy the performance as an adhesive.

Example 8 An adhesive was prepared in the same manner as in Example 1 except that 3 parts by weight of higher alcohol B was used instead of 1 part by weight of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 9 An adhesive was prepared in the same manner as in Example 1, except that 8 parts by weight of higher alcohol B was used in place of 1 part by weight of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 10 An adhesive was prepared in the same manner as in Example 1 except that 3 parts by weight of higher alcohol C was used in place of 1 part by weight of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 11 The amount of higher alcohol C used in Example 10 was increased to 5
An adhesive was prepared in the same manner as in Example 1 except that the parts by weight were changed. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 12 The amount of higher alcohol C used in Example 10 was 8
An adhesive was prepared in the same manner as in Example 1 except that the parts by weight were changed. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 13 In place of the polyvinyl acetate used in Example 2, 15 mol% of ethyl acrylate was copolymerized with a polymerization degree of 10.
An adhesive was prepared in the same manner as in Example 2 except that 100 parts by weight of modified polyvinyl acetate No. 50 was used. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 14 An adhesive was prepared in the same manner as in Example 1 except that 5 parts by weight of higher alcohol D was used in place of 1 part by weight of higher alcohol A used in Example 1. Example 1 of this adhesive
As a result of evaluation in the same manner as in Table 3, it showed the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 15 An adhesive was prepared in the same manner as in Example 1 except that 8 parts by weight of higher alcohol E was used in place of 1 part by weight of higher alcohol A used in Example 1. Example 1 of this adhesive
As a result of evaluation in the same manner as in Table 3, it showed the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 16 100 parts by weight of polyvinyl acetate having a degree of polymerization of 2500, 100 parts by weight of methanol, and 3 parts by weight of higher alcohol A shown in Table 1 were placed in a mixer and stirred and mixed at room temperature for about 1 hour to prepare an adhesive. As a result of measuring the pot life and adhesive strength of this adhesive according to Test Method I and Test Method II described below,
It exhibited the characteristics shown in Table 3, and was able to satisfy the performance as an adhesive.

Example 17 In place of the polyvinyl acetate used in Example 16,
Polymerization degree of 15 mol% copolymerized with ethyl acrylate
An adhesive was prepared in the same manner as in Example 16 except that 100 parts by weight of modified polyvinyl acetate of No. 050 was used. As a result of evaluating this adhesive in the same manner as in Example 16, it exhibited the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Example 18 In place of the polyvinyl acetate used in Example 16,
Example 16 except that 100 parts by weight of modified polyvinyl acetate with a degree of polymerization of 850 copolymerized with 5 mol% crotonic acid was used.
An adhesive was prepared in the same manner as above. Example 16 of this adhesive
As a result of evaluation in the same manner as in Table 3, it showed the properties shown in Table 3, and was found to have satisfactory performance as an adhesive.

Comparative Example 1 The amount of higher alcohol A used in Example 1 was reduced to 0.
An adhesive was prepared in the same manner as in Example 1 except that the amount was changed to 5 parts by weight. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under any conditions, the pot life was short.

Comparative Example 2 The amount of higher alcohol A used in Example 1 was increased to 16
An adhesive was prepared in the same manner as in Example 1 except that the parts by weight were changed. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although the pot life was satisfactory under all conditions, the adhesive strength was low.

Comparative Example 3 An adhesive was prepared in the same manner as in Example 1, except that 0.7 parts by weight of higher alcohol B was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under both normal and high humidity conditions, the pot life was short.

Comparative Example 4 An adhesive was prepared in the same manner as in Example 1, except that 16 parts by weight of higher alcohol B was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. There were no problems with pot life under any conditions, but
Adhesive strength was low.

Comparative Example 5 An adhesive was prepared in the same manner as in Example 1, except that 0.7 parts by weight of higher alcohol D was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under any conditions, the pot life was short.

Comparative Example 6 An adhesive was prepared in the same manner as in Example 1, except that 0.7 parts by weight of higher alcohol E was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under any conditions, the pot life was short.

Comparative Example 7 An adhesive was prepared in the same manner as in Example 1, except that 4 parts by weight of polyoxyethylene cetyl ether was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under any conditions, the pot life was short under high temperature atmospheres of 20°C and 30°C.

Comparative Example 8 In place of higher alcohol A used in Example 1, 2.0% of polyoxyethylene glycerin monostearate was used.
An adhesive was prepared in the same manner as in Example 1 except that parts by weight were used. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there were no problems with adhesive strength under any conditions, the pot life was short under high temperature atmospheres of 20°C and 30°C.

Comparative Example 9 An adhesive was prepared in the same manner as in Example 1, except that 3.3 parts by weight of stearylamine was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there was no problem in adhesive strength under any conditions, the pot life was short under a high temperature atmosphere of 30°C.

Comparative Example 10 An adhesive was prepared in the same manner as in Example 1, except that 1 part by weight of glycerin monoacetate monostearate was used in place of higher alcohol A used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although there was no problem in adhesive strength under any conditions, the pot life was short under a high temperature atmosphere of 30°C.

Comparative Example 11 In place of 100 parts by weight of polyvinyl acetate used in Example 1, 50 parts by weight of the same polyvinyl acetate as used in Example 1 was used.
Same as Example 1 except that 50 parts by weight of partially saponified polyvinyl acetate with a degree of polymerization of 700 and a degree of saponification of 10 mol% was used, and 1 part by weight of propylene glycol monostearate was used instead of higher alcohol A. An adhesive was prepared. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although the pot life was satisfactory under all conditions, the adhesive strength was significantly lower under high humidity.

Comparative Example 12 In place of 100 parts by weight of polyvinyl acetate used in Example 1, 60 parts by weight of the same polyvinyl acetate as used in Example 1 was used.
Same as Example 1 except that 40 parts by weight of partially saponified polyvinyl acetate with a degree of polymerization of 1000 and a degree of saponification of 20 mol% was used, and 1 part by weight of diglycerol monostearate was used instead of higher alcohol A. An adhesive was prepared. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. Although the pot life was satisfactory under all conditions, the adhesive strength was significantly lower under high humidity.

Comparative Example 13 An adhesive was prepared in the same manner as in Example 1 except that higher alcohol A was not used in Example 1. As a result of evaluating this adhesive in the same manner as in Example 1, it exhibited the characteristics shown in Table 5. There was no problem with adhesive strength under any conditions, but pot life was short under any conditions.

Comparative Examples 14, 15 and 16 Examples 16, 1
In each of Comparative Example 14, adhesives were prepared in the same manner as in Examples 16, 17, and 18, except that higher alcohol A was not used in each of Comparative Example 14.
, 15 and 16. As a result of evaluating these adhesives in the same manner as in Example 16, they exhibited the characteristics shown in Table 5, and the adhesives of Comparative Examples 14, 15, and 16 all had short pot life.

Test Method I (Pot life evaluation method) Using a comb trowel as specified in JIS A 5536, the adhesive was applied onto an asbestos cement board (flexible board) at a coating amount of 350 g/m2. Coated. Every 5 minutes after application, the adhesive-applied surface is laminated to a vinyl floor tile piece (40 x 40 x 2 mm), and a load of 1 kg is applied on the bonded body for 5 seconds. Next, after removing the load, the flexible board of the bonded body is immediately peeled off. At this time, check the rate of adhesive transfer from the flexible board to the bonding surface of the vinyl floor tile piece, and determine the maximum open time when this rate is not less than 80% by weight. Use time. The test conditions were 3 temperatures: 5°C, 20°C, and 30°C.
level.

Test method II (adhesive strength evaluation method) J
In accordance with the method described in IS A 5536, using a flexible board (70 x 70 x 8 mm) as the base material and composition vinyl floor tiles as the vinyl tile, the coating amount was 350 g/m2 with a comb trowel. Adhesive was applied to one side of the flexible board. After applying the adhesive, a vinyl tile was attached after an open time of 5 minutes, and a weight of 1 kg was placed on top of the tile for 5 seconds, and then the weight was removed. Curing is at 20℃, 65%RH
The experiment was carried out under the following conditions for 48 hours.

[0056] The adhesive strength was measured under the following two conditions using the JIS jig described above. Normal condition: The sample after curing as described above was measured as it was. High humidity condition: After the above curing, the sample was further heated at 20℃ for 9
After being left for 7 days under 0% RH conditions, the same measurements were taken. Furthermore, among the measured adhesive strength values, 12 kgf/cm2
Adhesive strength above this means that the adherend material will break.

Explanation of abbreviations in the table PVAc: Polyvinyl acetate AR: Polyvinyl acetate modified by ethyl acrylate copolymerization CA: Polyvinyl acetate modified by crotonic acid copolymerization PH-P
VAc: Partially saponified polyvinyl acetate MeOH: Methyl alcohol St-Ca: Calcium stearate POE: Polyoxyethylene cetyl ether POES: Polyoxyethylene glycerin monostearate SA: Stearylamine GASE: Glycerin monoacetate monostearate PGS: Propylene glycol monostearate D
GS: diglycerin monostearate

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

[0062]

[Table 5]

[0063]

[Effects of the Invention] As explained above, according to the adhesive of the present invention, by incorporating a higher alcohol as a retarder into an organic solvent-based adhesive containing a vinyl acetate polymer, the adhesive can be used for a long time and stably. It has a long pot life and also has excellent adhesive strength in a high humidity atmosphere.

Claims (2)

[Claims] [Claim 1] It contains a vinyl acetate polymer, a higher alcohol, and an organic solvent, and the content of the higher alcohol is 1 to 15 parts by weight based on 100 parts by weight of the vinyl acetate polymer. glue. 2. The adhesive according to claim 1, wherein the higher alcohol is an alcohol having 5 to 28 carbon atoms.