JPH09249865A - Adhesive composition and paper tube using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive composition, excellent not only in moisture and heat resistances but also in elastic modulus and initial adhesive strength of a membrane thereof and accordingly providing a paper tube produced at a high temperature and high humidity excellent in compressive and wet strengths. SOLUTION: This adhesive composition comprises 100 pts.wt. resin content in the polyvinyl acetate resin-based emulsion obtained by an emulsion polymerization of 100 pts.wt. vinyl acetate monomer with 0.1-5.0 pts.wt. monomer containing a carboxyl group in the presence of polyvinyl alcohol as a protecting colloid, 0.5-5.0 pts.wt. polyamide epichlorohydrin as a water-soluble epoxy resin. 80-170 pts.wt. inorganic filler, 35-70 pts.wt. at least one selected from polyvinyl alcohol, a polyvinyl alcohol modified by carboxyl groups, a starch and a dextrin and 1.0-5.0 pts.wt. boric acid. A paper tube is obtained by using the adhesive composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive composition used in various applications, and more particularly, when a cardboard is produced by winding cardboard around a metal mandrel, the side of the cardboard wound around the metal mandrel is produced. The present invention relates to an adhesive composition preferably used for adhering edges to each other, and a paper tube manufactured by using the adhesive composition.

[0002]

2. Description of the Related Art A paper tube used as a mandrel for winding a sheet-shaped article such as paper, foil, and woven fabric is usually a cardboard that is spirally wound around a metal mandrel and adjacent side edges of the cardboard are used. It is manufactured by bonding parts together with an adhesive. The adhesive used for manufacturing such a paper tube is manufactured based on starch, polyvinyl alcohol (PVA), polyvinyl vinyl acetate and the like.

For example, in Japanese Patent Laid-Open No. 5-125341, the resin content of a vinyl acetate resin emulsion is
An adhesive composition is disclosed in which an inorganic filler, PVA, and boric acid are added in predetermined proportions.

[0004]

Since the paper tube is required to have a pressure resistance so that the paper tube is not damaged by the pressure of the sheet-like article to be wound, the adhesive used for manufacturing the paper tube is The film, when dried, must have a high modulus. Further, when manufacturing a paper tube, the diameter of the paper tube to be manufactured must be made constant, and as an adhesive for manufacturing the paper tube, a cardboard wound around a metal core is fixed. It is also necessary to have an initial adhesiveness capable of maintaining the diameter.

In the adhesive composition disclosed in the above-mentioned publication, the adhesive film has a high elastic modulus, and the paper tube produced has excellent pressure resistance. In addition, the initial adhesive strength is also excellent. However, the paper tube is required to have further pressure resistance depending on the sheet-like article to be wound, and therefore, even as an adhesive used for manufacturing the paper tube, the film has a higher elastic modulus and an initial adhesive strength. Further improvement is required.

It is also known that the adhesive film has a high strength in order to increase the pressure resistance of the paper tube by giving strength to the paper tube to be produced. For this reason, for example, as a protective colloid. Adhesives using a strong isobutylene-maleic anhydride polymer have also been developed. However, such an adhesive has a problem that a satisfactory moisture resistance strength cannot be obtained, and the strength reduction of the paper tube due to manufacturing the paper tube at high temperature and high humidity cannot be suppressed.

The present invention solves such a problem, and its purpose is not only excellent in moisture resistance and heat resistance, but also excellent in film strength and initial adhesive strength, and therefore at high temperature and An object of the present invention is to provide an adhesive composition capable of making a paper tube manufactured under high humidity excellent in pressure resistance and humidity resistance.

[0008]

The present invention relates to a vinyl acetate resin emulsion obtained by emulsion-polymerizing a carboxyl group-containing monomer with a vinyl acetate monomer in the presence of a protective colloid at a predetermined ratio. As a water-soluble epoxy resin, polyamide epichlorohydrin represented by the following structural formula, and as a polymer, general-purpose PVA,
By adding any one of carboxyl group-modified PVA, starch, and dextrin, an inorganic filler, and boric acid in a predetermined ratio, moisture resistance and heat resistance are significantly improved, and the elastic modulus of the adhesive film and This is based on the finding that the initial adhesive strength is also improved.

[0009]

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The adhesive composition according to claim 1 is a vinyl acetate obtained by emulsion polymerization of 0.1 to 5.0 parts by weight of a carboxyl group-containing monomer with 100 parts by weight of a vinyl acetate monomer in the presence of a protective colloid. With respect to 100 parts by weight of the resin content of the resin emulsion, 0.5 to 5.0 parts by weight of polyamide epichlorohydrin, 80 to 170 parts by weight of an inorganic filler, 1.0 to 5.0 parts by weight of boric acid, and 35
˜70 parts by weight of polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, starch, and at least one selected from dextrins are added.

The adhesive composition according to claim 2 is used for adhering adjacent side edges of cardboard when the cardboard is wound around a mandrel to manufacture a paper tube.

The paper tube according to claim 3 is manufactured by bonding the adjacent side edges of the cardboard wrapped around the mandrel with the adhesive composition according to claim 1. And

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the adhesive composition of the present invention, acetic acid obtained by emulsion polymerization of 0.1 to 5.0 parts by weight of a carboxyl group-containing monomer with 100 parts by weight of vinyl acetate monomer in the presence of a protective colloid. The main component is vinyl resin emulsion, and 0.5 to 100 parts by weight of the resin content of such vinyl acetate resin emulsion is used.
5.0 parts by weight of polyamide epichlorohydrin, 80 to 17
0 parts by weight of inorganic filler, 1.0 to 5.0 parts by weight of boric acid,
Further, 35 to 70 parts by weight of polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, starch, and at least one selected from dextrin are added.

As the polymerization initiator for obtaining the vinyl acetate resin emulsion, potassium persulfate, ammonium persulfate, hydrogen peroxide, tartaric acid and the like are used alone or in combination of two or more thereof.

As the protective colloid, polyvinyl alcohol (PVA), carboxyl group-modified PVA, a copolymer of isobutylene and maleic anhydride, carboxymethyl cellulose and the like are used.

When the amount of the carboxyl group-containing monomer to be emulsion-polymerized is less than 0.1 part by weight based on 100 parts by weight of the vinyl acetate monomer, the obtained vinyl acetate resin emulsion is blended with a water-soluble epoxy resin such as polyamide epichlorohydrin. However, the adhesive composition finally obtained does not have sufficient hot water resistance and is inferior in moisture resistance. On the other hand, if it exceeds 5.0 parts by weight, the polymerization stability becomes poor.

Resin component of vinyl acetate resin emulsion 1
0.5 to 5.0 parts by weight of polyamide epichlorohydrin, and 80 to 170 parts by weight of inorganic filler per 100 parts by weight of 1.
0 to 5.0 parts by weight of boric acid, and 35 to 70 parts by weight of P
In the adhesive composition to which any one selected from VA, carboxyl group-modified PVA, starch and dextrin is added, an inorganic filler added to the vinyl acetate resin emulsion, PVA, carboxyl group-modified PVA,
By the action with starch or dextrin, the film of the adhesive has a high elastic modulus and has an excellent adhesive force. Further, the action of boric acid provides excellent initial adhesive strength and water resistance. Therefore, when the cardboard is wound around the metal mandrel to manufacture a paper tube, it is preferably used for adhering adjacent side edges of the cardboard spirally wound around the metal mandrel.

Resin component of vinyl acetate resin emulsion 1
With respect to 00 parts by weight, the water-soluble epoxy resin polyamide epichlorohydrin is less than 0.5 parts by weight,
The resulting adhesive composition does not have sufficient hot water resistance,
Also, the moisture resistance becomes poor. On the other hand, when the amount is more than 5.0 parts by weight, the stability of the obtained adhesive composition becomes poor. It is preferably 2 to 4 parts by weight.

Examples of the carboxyl group-modified PVA blended in the vinyl acetate resin emulsion include those obtained by reacting PVA with a carboxylic acid to introduce a carboxyl group at the end of PVA. Examples of the carboxylic acid used in the reaction include acrylic acid, methacrylic acid, and itaconic acid, but are not particularly limited.

The inorganic filler to be added to the vinyl acetate resin emulsion includes clay, aluminum hydroxide,
Calcium carbonate, kaolin, talc and the like can be used, but clay is particularly preferable.

Such an inorganic filler is used in an amount of 80 to 170 with respect to 100 parts by weight of the resin content of the vinyl acetate resin emulsion.
It is blended in the range of parts by weight. 80% inorganic filler
When the amount is less than the weight part, the strength of the adhesive film obtained by the adhesive composition decreases, so that when used in the production of paper tubes, the pressure resistance of the paper tube produced is inferior. Become. If the blending ratio of the inorganic filler is more than 170 parts by weight, the initial adhesive strength of the adhesive composition will decrease. In particular, the inorganic filler is preferably blended in an amount of 115 to 140 parts by weight based on 100 parts by weight of the resin content of the vinyl acetate resin emulsion.

Boric acid added to the vinyl acetate resin emulsion is a resin component of the vinyl acetate resin emulsion.
It is compounded in the range of 1.0 to 5.0 parts by weight with respect to 00 parts by weight. If the blending ratio of boric acid is less than 1.0 part by weight, the water resistance and the initial adhesive strength of the adhesive composition will decrease. When the proportion of boric acid is more than 5.0 parts by weight,
The temporal stability of the viscosity of the adhesive composition decreases. Especially,
Boric acid is a resin component of vinyl acetate resin emulsion.
It is preferable to add 2.0 to 3.5 parts by weight with respect to parts by weight.

The PVA, carboxyl group-modified PVA, starch or dextrin blended in the vinyl acetate resin emulsion is blended in the range of 35 to 70 parts by weight with respect to 100 parts by weight of the resin content of the vinyl acetate resin emulsion. It PVA is also used when emulsion-polymerizing a vinyl acetate resin emulsion, but since it is not completely polymerized during this emulsion polymerization, PVA is used after the polyvinyl acetate resin emulsion is obtained. Is added.

The blending ratio of PVA, carboxyl group-modified PVA, carboxyl group-modified PVA, starch, or dextrin is obtained from the balance with the blending ratio of inorganic filler and boric acid. PVA, carboxyl group-modified PVA, If the blending ratio of starch or dextrin is less than 35 parts by weight, the strength of the adhesive film obtained by the adhesive composition decreases,
When used to manufacture a paper tube, the pressure resistance of the manufactured paper tube becomes poor. PVA, carboxyl group modified P
When the blending ratio of VA, starch, or dextrin is more than 70 parts by weight, the initial adhesive strength of the adhesive composition decreases. Particularly, PVA, carboxyl group-modified PVA, starch, or dextrin is preferably added in an amount of 45 to 60 parts by weight with respect to 100 parts by weight of the resin content of the vinyl acetate resin emulsion.

[0025]

Embodiments of the present invention will be described below in detail.

First, an adhesive composition was prepared by adding a predetermined amount of water-soluble epoxy resin polyamide epichlorohydrin, inorganic filler, PVA, and boric acid to a vinyl acetate resin emulsion. Examples 1-3 are shown. Further, comparative examples for Examples 1 to 3 are shown in Comparative Examples 1 to 10.

Example 1 A reactor having a stirrer, a thermometer, and a dropping funnel was charged with 110 parts by weight of water and 11 parts by weight of PVA (Kuraray Co., Ltd., trade name "CST"). The PVA was dissolved in water with stirring at a temperature of 90 ° C. for 1 hour. Then, the obtained PVA solution was cooled to 75 ° C.

Next, a mixed monomer in which 100 parts by weight of vinyl acetate monomer and 2 parts by weight of acrylic acid were sufficiently mixed was prepared, and 0.3 part by weight of hydrogen peroxide solution as a polymerization catalyst and 0.2 part by weight of tartaric acid were prepared. Were mixed to obtain a polymerization catalyst. Then, 10% of the prepared mixed monomer and 20% of a polymerization catalyst of a mixture of hydrogen peroxide solution and tartaric acid were added to the PVA solution already obtained to carry out initial polymerization.

Thereafter, the rest (90%) of the mixed monomer of vinyl acetate monomer and acrylic acid was added dropwise to the prepolymer over 3 hours, and the rest of the polymerization catalyst which was a mixture of hydrogen peroxide solution and tartaric acid. (80%) was added dropwise over 3.5 hours to complete the emulsion polymerization. Then, the obtained polymer was aged. The polymer was aged at a temperature of 85 ° C. for 1 hour after the addition of the vinyl acetate monomer was completed. As a result, solid content 48%, viscosity 8,500cps
To obtain a vinyl acetate resin emulsion.

Obtained vinyl acetate resin emulsion 1
<00 parts by weight <2.0 parts by weight of polyamide epichlorohydrin as a water-soluble epoxy resin and additives such as a plasticizer, an antifoaming agent and an antiseptic agent are added, and the solid content is adjusted to 45% by adjusting with water. , And the viscosity was 4,000 cps.

Next, 125 parts by weight of clay (30% slurry) as an inorganic filler and 100 parts by weight of the resin content, PV
A (15% aqueous solution) 50 parts by weight, boric acid (3% aqueous solution) 2.5
By adding each part by weight and adjusting with water,
An adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated by the following method. The results of each performance evaluation are shown in Table 1.

(1) Laminated ring crush strength According to JIS P-8126 "Paperboard compressive strength test method (ring crush method)", the ring crush strength in the longitudinal and transverse directions of the paper core paper is as follows. I asked. Two sheets of Fukuyama Paper Co., Ltd. class B paper tube base paper were prepared. One base paper was coated with the adhesive composition at a coating amount of 30 g / m ^{2 in} the vertical direction, and the other base paper was coated in the horizontal direction. 30 g of adhesive composition on
The base papers were applied with a coating amount of m ² , and the base papers were attached to each other in the longitudinal direction and the transverse direction, and then pressure-bonded with a pressure of 70 g / cm ² . Then, it was allowed to cure for 24 hours in an atmosphere of a temperature of 20 ° C. and a relative humidity of 65% RH. The laminated base paper thus obtained is 12.7 mm wide and 152.4 mm long.
The test piece was cut into two pieces to obtain two test pieces.

One of the test pieces was used for measuring the normal strength.
72 in a temperature of 20 ° C and relative humidity of 65% RH
After curing for a period of time, it was set in a compression tester and compressed at a compression speed of 10 mm / min to measure the ring crush strength.

The other test piece was used for measuring the humidity resistance strength, and was adjusted to have a water content of 12 to 13% in an atmosphere of a temperature of 50 ° C. and a relative humidity of 95% RH. Then, this test piece was set in a compression tester and compressed at a compression speed of 10 mm / min to measure the ring crush strength.

In Example 1, the ring crush strength of the adhesive composition was 12 Okgf in the normal state (20 ° C. × 65% RH), and the moisture resistance strength when cured in an atmosphere of 50 ° C. × 90% RH was obtained.
It was 85 kgf.

(2) Initial adhesive strength (shear adhesive strength) From a B-class paper tube base paper made by Fukuyama Paper Co., Ltd., 10 cm × 4 cm and 10 cm ×
Three pairs of rectangular paper pieces each having a size of 5 cm were cut out, and the pair of paper pieces were adhered to each other by the adhesive composition.
The coating amount of the adhesive composition for adhering a pair of paper pieces is 30
g / m ² (wet), coating speed is 0.6 m / sec, time (open time) from application of adhesive composition to one piece of paper to application of the other piece of paper is 0.5 seconds, compression pressure of both pieces of paper 3 kg
/ Cm ^2, and the compression time of each set of paper pieces is 6
Seconds, 8 seconds, 10 seconds. Then, after leaving for 0.5 seconds after releasing the compression, the both adhered paper pieces were pulled at a pulling speed of 10 with an initial adhesive force measuring device (manufactured by JT Toshi Co., Ltd.).
The tensile shear strength was measured by pulling at 0 m / min. During the measurement, the atmosphere was fixed at 20 ° C. and 65% RH.

In the adhesive composition of Example 1, the pressing time was 6
2.51kg seconds at 0.72kg / cm ^2, 8 seconds at 1.66kg / cm ^2, 10 seconds
A tensile shear strength of / cm ² was obtained respectively.

(3) Evaluation of water resistance and heat resistance The paper tube base paper used for evaluation and measurement of initial adhesive strength was 25 mm × 50
It was cut into a rectangular shape having a size of mm to obtain two pieces of paper. On one side of the obtained one piece of paper, 0.05% of the adhesive composition
A test piece was prepared by applying a coating amount of g / (25 mm) ² (wet) and sticking the other piece of paper. And, this test piece 1
20 kg after being compressed for 60 seconds at a pressure of kg / (25 mm) ^2.
It was aged for 24 hours under the atmosphere of temperature of ℃ and relative humidity of 65% RH. In this way, a pair of test pieces was obtained. Then, a weight of 100 g was hung on one paper piece of one test piece and immersed in warm water of 40 ° C., and the time until both test pieces were peeled off at the adhesive surface and dropped was measured. In addition, a weight of 100 g was suspended on one paper piece of the other test piece and immersed in boiling water, and the time until both test pieces peeled off at the adhesive surface and dropped was measured.

In the adhesive composition of Example 1, when soaked in warm water of 40 ° C., both pieces of paper were separated by 72 before peeling and dropping.
It took more than 2 hours, and boiling water required more than 2 hours.

(4) Evaluation of viscosity stability over time The adhesive composition was left in an atmosphere of 40 ° C. for one month, and then the viscosity of the adhesive was measured. Then, the viscosity increase rate was calculated in comparison with the viscosity before standing.

In the adhesive composition of Example 1, the viscosity increase rate was 1.1 times.

<Example 2> When the vinyl acetate resin emulsion was polymerized in Example 1, vinyl acetate monomer 1
The amount of acrylic acid was 0.5 part by weight with respect to 00 parts by weight. Further, with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion, 0.8 part by weight of polyamide epichlorohydrin, 90 parts by weight of clay (30% slurry) as an inorganic filler, 40 parts of PVA (15% aqueous solution) Parts by weight,
By adding 1.2 parts by weight of boric acid (3% aqueous solution), and adjusting with water, an adhesive composition having a solid content of 24.5% and a viscosity of 460 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 114 kgf in the normal state and 50 ° C ×
78k as humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.54 / cm ² at 1.63 kg / cm ^2, 10 seconds at 0.75 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.0. The results are also shown in Table 1.

<Example 3> When the vinyl acetate resin emulsion was polymerized in Example 1, vinyl acetate monomer 1
The amount of acrylic acid was 4.5 parts by weight based on 00 parts by weight. In addition, the obtained vinyl acetate resin emulsion 1
4.6 parts by weight of polyamide epichlorohydrin for 100 parts by weight
By weight, clay as an inorganic filler (30% slurry) 1
65 parts by weight, PVA (15% aqueous solution) 65 parts by weight, boric acid (3
% Aqueous solution) 4.7 parts by weight were respectively added and adjusted with water to obtain an adhesive composition having a solid content of 26.5% and a viscosity of 560 cps.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 123 kgf in the normal state and 50 ° C. ×
87k as the moisture resistance strength when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.40 kg / cm ² at 1.45 kg / cm ^2, 10 seconds at 0.53 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.6 times. The results are also shown in Table 1.

Comparative Example 1 When a vinyl acetate resin emulsion was polymerized in the same manner as in Example 1, the amount of acrylic acid added was 0.05 per 100 parts by weight of the vinyl acetate monomer.
Parts by weight were used. Further, the compounding amount of polyamide epichlorohydrin was 0.3 part by weight with respect to 100 parts by weight of the obtained vinyl acetate resin emulsion, and 125 parts by weight of clay (30% slurry) as an inorganic filler and PVA were used in the same manner as in Example 1. By adding 50 parts by weight of a 15% aqueous solution and 2.5 parts by weight of boric acid (3% aqueous solution) and adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 119 kgf in the normal state and 50 ° C ×
81k as the humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.48kg / cm ² at 1.66 kg / cm ^2, 10 seconds at 0.68 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, in warm water at 40 ° C, it took 72 hours or more for both paper pieces to peel and fall, but in boiling water, the time for both paper pieces to peel and fall Is 1 minute and Examples 1 to 3
Was significantly inferior to. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. The results are also shown in Table 1.

Comparative Example 2 When a vinyl acetate resin emulsion was polymerized in the same manner as in Example 1, the amount of acrylic acid to be mixed was 6.0 with respect to 100 parts by weight of vinyl acetate monomer.
Parts by weight were used. In this case, the polymerization stability was poor, the emulsion gelled during the polymerization, and the adhesive could not be obtained.

Comparative Example 3 To 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1, clay (30% slurry) as an inorganic filler was not added at all. , Polyamide epichlorohydrin, PVA
The addition rates of (15% aqueous solution) and boric acid (3% aqueous solution) were 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight, respectively, as in Example 1. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 400 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. The ring crush strength is 103 kgf in the normal state, and the humidity resistance strength when cured in an atmosphere of 50 ° C x 90% RH is 70 kgf.
It was inferior to 3. The initial adhesive strength (shear adhesive strength) is 0.73 kg / cm ² when the compression time is 6 seconds and 1.54 kg when the compression time is 8 seconds.
/ Cm ² , 2.55kg / cm ² in 10 seconds. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 1.

Comparative Example 4 The clay (30% slurry) as an inorganic filler was added to 200 parts by weight of the vinyl acetate resin emulsion obtained in the same manner as in Example 1 with respect to 100 parts by weight of the resin content. In the same manner as in Example 1, the addition ratios of polyamide epichlorohydrin, PVA (15% aqueous solution) and boric acid (3% aqueous solution) were 2.0 parts by weight, respectively.
The parts were 50 parts by weight, 50 parts by weight and 2.5 parts by weight. Then, by adjusting with water, an adhesive composition having a solid content of 25.5% and a viscosity of 550 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. The ring crush strength was 125 kgf in the normal state, and the humidity resistance strength when cured in an atmosphere of 50 ° C x 90% RH was 88 kgf. The initial adhesive strength (shear adhesive strength) is 0 when the compression time is 6 seconds.
^{30kg / cm 2, 1.98kg / cm} 2 at 8 seconds at 1.06kg / cm ^2, 10 seconds
Then, it was inferior to Examples 1 to 3. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 1.

<Comparative Example 5> With respect to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 1, the addition ratio of clay (30% slurry) as an inorganic filler was 60%. Parts by weight, polyamide epichlorohydrin, PVA (15% aqueous solution) and boric acid (3% aqueous solution)
As in Example 1, the addition ratios thereof were 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight, respectively. Then, by adjusting with water, an adhesive composition having a solid content of 25.5% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 105 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
1 kgf, which was inferior to those of Examples 1 to 3. The initial adhesive force (shear adhesive force) is 0.53 kg / cm when the compression time is 6 seconds.
^2, was 2.44 kg / cm ² at 1.46 kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 1.

Comparative Example 6 Polyamide epichlorohydrin was prepared by adding 30 parts by weight of PVA (15% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1. As in Example 1, the addition ratios of clay (30% slurry) and boric acid (3% aqueous solution) as inorganic fillers were 2.0
The parts were 125 parts by weight, 125 parts by weight and 2.5 parts by weight. And
By adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 400 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 106 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
It was 0 kgf, which was inferior to those of Examples 1 to 3. The initial adhesive strength (shear adhesive strength) is 0.48 kg / cm when the compression time is 6 seconds.
^2, was 2.31 kg / cm ² at 1.50 kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 1.

Comparative Example 7 Polyamide epichlorohydrin was prepared by adding 90 parts by weight (15% aqueous solution) of PVA to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 1. As in Example 1, the addition ratios of clay (30% slurry) and boric acid (3% aqueous solution) as inorganic fillers were 2.0
The parts were 125 parts by weight, 125 parts by weight and 2.5 parts by weight. And
By adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 450 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 122 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 6 kgf. The initial adhesive strength (shear adhesion) is, 0.28 kg at compression time is 6 seconds ^{/ cm 2, 1.05kg / cm 2} , 10 in 8 seconds
It was 2.03 kg / cm ^{2 in} seconds, which was inferior to Examples 1 to 3. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. The results are also shown in Table 1.

Comparative Example 8 Polyamide epichlorohydrin was prepared by adding 0.5 part by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1. The addition ratio of clay (30% slurry) and PVA (15% aqueous solution) as inorganic fillers was 2.0, respectively, as in Example 1.
The parts are 125 parts by weight, 125 parts by weight and 50 parts by weight. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 121 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 3 kgf. The initial adhesive strength (shear adhesion) is, 0.36 kg at compression time is 6 seconds ^{/ cm 2, 1.22kg / cm 2} , 10 in 8 seconds
It was 2.14 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, with hot water of 40 ° C., both paper pieces are inferior to Examples 1 to 3 until they peel and fall, and even with boiling water, both paper pieces are Before peeling and dropping 1.5
It was inferior in time and to Examples 1 to 3. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 1.

Comparative Example 9 Polyamide epichlorohydrin was prepared by adding 6.0 parts by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1. The addition ratio of clay (30% slurry) and PVA (15% aqueous solution) as inorganic fillers was 2.0, respectively, as in Example 1.
The parts are 125 parts by weight, 125 parts by weight and 50 parts by weight. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 118 kgf in the normal state and 50 ° C ×
84k as the humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.46 kg / cm ² at 1.53 kg / cm ^2, 10 seconds at 0.59 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and drop with warm water at 40 ° C, and for boiling water to take 2 hours or more for both paper pieces to peel off and fall. did. The viscosity increase rate as an evaluation of the viscosity stability over time was 3.2 times, and Examples 1 to 3
Was inferior to. The results are also shown in Table 1.

Comparative Example 10 In the same manner as in Example 1, no acrylic acid was added at the time of polymerizing the vinyl acetate resin emulsion, and the obtained vinyl acetate resin emulsion was treated with polyamide. An adhesive composition having a solid content of 25% and a viscosity of 350 cps was obtained without adding any epichlorohydrin, and without adding any inorganic filler, PVA and boric acid.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 100 kgf in the normal state and 50 ° C x
Moisture resistance of 63k when cured in an atmosphere of 90% RH
It was inferior to gf and Examples 1 to 3. The initial adhesive strength (shear adhesive strength) is 0.55 kg / cm ² when the compression time is 6 seconds,
Was 2.38kg / cm ² at 1.49kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, in warm water of 40 ℃, the time until both paper pieces peel and drop is 10 minutes, in boiling water, the time until both paper pieces peel and drop is 30 seconds, It was significantly inferior to Examples 1 to 3. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.0. The results are also shown in Table 1.

[0066]

[Table 1]

Next, Examples 4 to 6 show adhesive compositions in which polyamide epichlorohydrin, an inorganic filler, a carboxyl group-modified PVA, and boric acid were mixed in a predetermined amount in a vinyl acetate resin emulsion. . In addition, the comparison target with respect to these Examples 4 to 6,
It shows as Comparative Examples 11-18.

<Example 4> 2.0 parts by weight of polyamide epichlorohydrin was added to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1,
As an inorganic filler, 125 parts by weight of clay (30% slurry), 50 parts by weight of carboxyl group-modified PVA (15% aqueous solution), and 2.5 parts by weight of boric acid (3% aqueous solution) were added, respectively, and adjusted with water. By this, solid content 25%, viscosity 500c
An adhesive composition of ps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 120 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 8 kgf. The initial adhesive strength (shear adhesion) is, 0.72 kg at compression time is 6 seconds ^{/ cm 2, 1.65kg / cm 2} , 10 in 8 seconds
It was 2.49 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 2.

<Example 5> When vinyl acetate resin emulsion was polymerized in Example 4, vinyl acetate monomer 1
A vinyl acetate resin emulsion was obtained by adjusting the amount of acrylic acid to be 0.5 parts by weight based on 00 parts by weight. Next, with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion, 0.8 parts by weight of polyamide epichlorohydrin, 90 parts by weight of clay (30% slurry) as an inorganic filler, and carboxyl group-modified PVA (15% Aqueous solution) 40 parts by weight and boric acid (3% aqueous solution) 1.2 parts by weight were added respectively and adjusted with water to give a solid content of 24.5% and a viscosity of 460c
An adhesive composition of ps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 115 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.76 kg at compression time is 6 seconds ^{/ cm 2, 1.66kg / cm 2} , 10 in 8 seconds
It was 2.52 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 2.

<Example 6> When the vinyl acetate resin emulsion was polymerized in Example 4, vinyl acetate monomer 1
The amount of acrylic acid was 4.5 parts by weight based on 00 parts by weight. In addition, the obtained vinyl acetate resin emulsion 1
The blending amount of polyamide epichlorohydrin to 00 parts by weight was 4.6 parts by weight, and further 165 parts by weight of clay (30% slurry) as an inorganic filler, carboxyl group-modified P
65 parts by weight of VA (15% aqueous solution), boric acid (3% aqueous solution)
By adding 4.7 parts by weight of each and adjusting with water, an adhesive composition having a solid content of 26.5% and a viscosity of 560 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 124 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.57 kg at compression time is 6 seconds ^{/ cm 2, 1.46kg / cm 2} , 10 in 8 seconds
It was 2.41 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.8 times. The results are also shown in Table 2.

<Comparative Example 11> When a vinyl acetate resin emulsion was polymerized in the same manner as in Example 4, the amount of acrylic acid added was 100 parts by weight with respect to 100 parts by weight of the vinyl acetate monomer.
05 parts by weight. The amount of polyamide epichlorohydrin was 0.3 part by weight per 100 parts by weight of the obtained vinyl acetate resin emulsion, 125 parts by weight of clay (30% slurry) as an inorganic filler, and carboxyl group-modified PVA (15% aqueous solution). ) 50 parts by weight, boric acid (3%
(Aqueous solution) 2.5 parts by weight of each was added and adjusted with water to obtain an adhesive composition having a solid content of 25% and a viscosity of 500 cps.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 121 kgf in the normal state and 50 ° C ×
82k as humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.43kg / cm ² at 1.69 kg / cm ^2, 10 seconds at 0.70 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, in warm water at 40 ° C, it took 72 hours or more for both paper pieces to peel and fall, but in boiling water, the time for both paper pieces to peel and fall Is 5 minutes and Examples 4 to 6
Was significantly inferior to. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 2.

Comparative Example 12 Clay as an inorganic filler (30% slurry) was added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 4.
Polyamide epichlorohydrin, carboxyl group-modified PVA (15% aqueous solution) and boric acid (3
% Aqueous solution), as in Example 4, respectively, 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight. And by adjusting with water, solid content 25%, viscosity 400c
An adhesive composition of ps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 104 kgf in the normal state and 50 ° C. ×
71k as the humidity resistance when cured in an atmosphere of 90% RH
It was gf, which was inferior to Examples 4 to 6. Also, the initial adhesive force (shear adhesive force) has a compression time of 6
0.75kg / cm ² in seconds, 1.75kg / cm ² in 8 seconds, 2.55kg in 10 seconds
/ Cm ² . Furthermore, in the water resistance evaluation test,
With hot water at 40 ° C., it took 72 hours or more for both pieces of paper to peel and fall, and for boiling water, two hours or more for peeling and drops of both pieces of paper. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. The results are also shown in Table 2.

Comparative Example 13 Clay (30% slurry), which is an inorganic filler, was added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 4.
And 200 parts by weight of polyamide epichlorohydrin, carboxyl group-modified PVA (15% aqueous solution) and boric acid (3% aqueous solution), respectively, in the same manner as in Example 4, 2.0 parts by weight, 50 parts by weight and It was 2.5 parts by weight. Then, by adjusting with water, the solid content of 25.5
%, A viscosity of 550 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 127 kgf in the normal state and 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.29 kg at compression time is 6 seconds ^{/ cm 2, 0.98kg / cm 2} , 10 in 8 seconds
It was 1.95 kg / cm ^{2 in} seconds, which was inferior to Examples 4 to 6. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. Table 2 shows the results
It is described together.

<Comparative Example 14> Clay (30% slurry), which is an inorganic filler, is added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 4.
And 60 parts by weight of polyamide epichlorohydrin, carboxyl group-modified PVA (15% aqueous solution) and boric acid (3% aqueous solution) were added in the same manner as in Example 4, respectively, 2.0 parts by weight, 50 parts by weight and It was 2.5 parts by weight. Then, by adjusting with water, the solid content of 25.5
%, An adhesive composition having a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 106 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
1 kgf, which was inferior to Examples 4 to 6. The initial adhesive strength (shear adhesive strength) is 0.55 kg / cm when the compression time is 6 seconds.
^2, was 2.41kg / cm ² at 1.50 kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.6 times. The results are also shown in Table 2.

Comparative Example 15 A carboxyl group-modified PVA (15% aqueous solution) was added in an amount of 30 parts by weight based on 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 4. The addition ratios of polyamide epichlorohydrin, clay (30% slurry) as an inorganic filler and boric acid (3% aqueous solution) were 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight, respectively, as in Example 4. . And by adjusting with water, solid content 25
%, An adhesive composition having a viscosity of 400 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 105 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
It was 2 kgf, which was inferior to Examples 4 to 6. The initial adhesive strength (shear adhesive strength) is 0.41 kg / cm when the compression time is 6 seconds.
Was 2.16 kg / cm ² at 1.38 kg / cm ^2, 10 seconds at ^2, 8 sec. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. The results are also shown in Table 2.

<Comparative Example 16> 90 parts by weight (15% aqueous solution) of the carboxyl group-modified PVA was added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 4. The addition ratios of polyamide epichlorohydrin, clay (30% slurry) as an inorganic filler and boric acid (3% aqueous solution) were 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight, respectively, as in Example 4. . And by adjusting with water, solid content 25
%, An adhesive composition having a viscosity of 450 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 123 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 8 kgf. The initial adhesive strength (shear adhesion) is, 0.22 kg at compression time is 6 seconds ^{/ cm 2, 0.86kg / cm 2} , 10 in 8 seconds
It was 1.99 kg / cm ^{2 in} seconds, which was inferior to Examples 4 to 6. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.5 times. The results are also shown in Table 2.

Comparative Example 17 Polyamide epichlorohydrin was prepared by adding 0.5 part by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 4. The addition rates of clay (30% slurry) and carboxyl group-modified PVA (15% aqueous solution) as inorganic fillers were 2.0 parts by weight, 125 parts by weight and 50 parts by weight, respectively, as in Example 4. . And by adjusting with water, solid content 25
%, An adhesive composition having a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 120 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 4 kgf. The initial adhesive strength (shear adhesion) is, 0.33 kg at compression time is 6 seconds ^{/ cm 2, 1.19kg / cm 2} , 10 in 8 seconds
It was 2.15 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, both hot water at 40 ° C. were inferior to those in Examples 4 to 6 for 60 hours until both paper pieces peeled off and dropped, and even with boiling water, both paper pieces peeled off. 1.5 hours before it falls,
It was inferior to Examples 4 to 6. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. Table 2 shows the results
It is described together.

Comparative Example 18 Polyamide epichlorohydrin was prepared by adding 6.0 parts by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 4. The addition rates of clay (30% slurry) and carboxyl group-modified PVA (15% aqueous solution) as inorganic fillers were 2.0 parts by weight, 125 parts by weight and 50 parts by weight, respectively, as in Example 4. . And by adjusting with water, solid content 25
%, An adhesive composition having a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 117 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 3 kgf. The initial adhesive strength (shear adhesion) is, 0.56 kg at compression time is 6 seconds ^{/ cm 2, 1.50kg / cm 2} , 10 in 8 seconds
It was 2.43 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and drop with warm water at 40 ° C, and for boiling water to take 2 hours or more for both paper pieces to peel off and fall. did. The viscosity increase rate as an evaluation of the viscosity stability over time was 3.9 times.
It was inferior to 6. The results are also shown in Table 2.

[0090]

[Table 2]

Next, Examples 7 to 9 show adhesive compositions in which a predetermined amount of polyamide epichlorohydrin, an inorganic filler, starch and boric acid were added to a vinyl acetate resin emulsion. In addition, the comparison targets for Examples 7 to 9 are Comparative Examples 19 to 26.
As shown.

<Example 7> Polyamide epichlorohydrin was added in an amount of 2.0 parts by weight to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 1,
125 parts by weight of clay (30% slurry) as inorganic filler, 50 parts by weight of starch (15% aqueous solution), boric acid (3%)
2.5 parts by weight of aqueous solution) was added and adjusted with water to obtain an adhesive composition having a solid content of 25% and a viscosity of 500 cps.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 124 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 6 kgf. The initial adhesive strength (shear adhesion) is, 0.65 kg at compression time is 6 seconds ^{/ cm 2, 1.60kg / cm 2} , 10 in 8 seconds
It was 2.43 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are shown in Table 3.

<Example 8> Vinyl acetate monomer was used when polymerizing the vinyl acetate resin emulsion in Example 7.
The amount of acrylic acid was 0.5 part by weight with respect to 00 parts by weight. Further, the compounding ratio of polyamide epichlorohydrin was set to 0.8 part by weight with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion. Furthermore, 90 parts by weight of clay (30% slurry), 40 parts by weight of starch (15% aqueous solution), boric acid (3% aqueous solution) as an inorganic filler, relative to 100 parts by weight of the resin content of the vinyl acetate resin emulsion.
By adding 1.2 parts by weight each and adjusting with water, an adhesive composition having a solid content of 24.5% and a viscosity of 460 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 120 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 1 kgf. The initial adhesive strength (shear adhesion) is, 0.71 kg at compression time is 6 seconds ^{/ cm 2, 1.59kg / cm 2} , 10 in 8 seconds
It was 2.48 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.0. The results are also shown in Table 3.

Example 9 Vinyl acetate monomer was used when polymerizing the vinyl acetate resin emulsion in Example 7.
The amount of acrylic acid was 4.5 parts by weight based on 00 parts by weight. Further, the compounding amount of polyamide epichlorohydrin was set to 4.6 parts by weight with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion. Furthermore, 165 parts by weight of clay (30% slurry) as inorganic filler, 65 parts by weight of starch (15% aqueous solution), boric acid (3% aqueous solution) per 100 parts by weight of vinyl acetate resin emulsion resin content
By adding 4.7 parts by weight of each and adjusting with water, an adhesive composition having a solid content of 26.5% and a viscosity of 560 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 127 kgf in the normal state and 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.52 kg at compression time is 6 seconds ^{/ cm 2, 1.40kg / cm 2} , 10 in 8 seconds
It was 2.36 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.6 times. The results are also shown in Table 3.

<Comparative Example 19> When a vinyl acetate resin emulsion was polymerized in the same manner as in Example 7, the amount of acrylic acid added was 100 parts by weight with respect to 100 parts by weight of the vinyl acetate monomer.
05 parts by weight. Further, the compounding amount of polyamide epichlorohydrin was set to 0.3 part by weight based on 100 parts by weight of the obtained vinyl acetate resin emulsion. Furthermore, 125 parts by weight of clay (30% slurry), 50 parts by weight of starch (15% aqueous solution) and 2.5 parts by weight of boric acid (3% aqueous solution) were added as inorganic fillers, respectively, and the solid content was adjusted by adding water. An adhesive composition having 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 121 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 2 kgf. The initial adhesive strength (shear adhesion) is, 0.62 kg at compression time is 6 seconds ^{/ cm 2, 1.61kg / cm 2} , 10 in 8 seconds
It was 2.41 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, with hot water of 40 ° C., it took 72 hours or more for both paper pieces to peel and fall, whereas with boiling water, both paper pieces peel and fall. It took 1 minute, which was significantly inferior to Examples 7-9. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. The results are also shown in Table 3.

Comparative Example 20 A clay (30% slurry) which is an inorganic filler is added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 7.
Was added in the same manner as in Example 7, except that polyamide epichlorohydrin, starch (15% aqueous solution) and boric acid (3% aqueous solution) were added in an amount of 2.0 parts by weight and 50 parts by weight, respectively.
It was set to 2.5 parts by weight and 2.5 parts by weight. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 400 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 105 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
1 kgf, which was inferior to those of Examples 7 to 9. The initial adhesive strength (shear adhesive strength) is 0.69 kg / cm when the compression time is 6 seconds.
^2, it was 2.50 kg / cm ² at 1.51kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. Table 3 shows the results
It is described together.

<Comparative Example 21> Clay as an inorganic filler (30% slurry) was added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 7.
Was added to 200 parts by weight, and polyamide epichlorohydrin, starch (15% aqueous solution) and boric acid (3% aqueous solution) were added in the same manner as in Example 7, respectively.
It was 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight. And by adjusting with water, solid content 25.5%, viscosity 550c
An adhesive composition of ps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 128 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.27 kg at compression time is 6 seconds ^{/ cm 2, 1.01kg / cm 2} , 10 in 8 seconds
It was 1.92 kg / cm ^{2 in} seconds, which was inferior to Examples 7 to 9. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. Table 3 shows the results
It is described together.

<Comparative Example 22> Clay as an inorganic filler (30% slurry) was added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 7.
Was added to 60 parts by weight, and the addition ratios of polyamide epichlorohydrin, starch (15% aqueous solution) and boric acid (3% aqueous solution) were 2.0% as in Example 7, respectively.
The parts were 50 parts by weight, 50 parts by weight and 2.5 parts by weight. Then, by adjusting with water, an adhesive composition having a solid content of 25.5% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 106 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
It was 3 kgf, which was inferior to those of Examples 7 to 9. The initial adhesive strength (shear adhesive strength) is 0.49 kg / cm when the compression time is 6 seconds.
^2, was 2.39kg / cm ² at 1.40 kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. The results are also shown in Table 3.

Comparative Example 23 Polyamide epichlorohydrin was prepared by adding 30 parts by weight of starch (15% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 7. The addition ratios of clay (30% slurry) and boric acid (3% aqueous solution) as inorganic fillers were the same as in Example 7, respectively.
It was 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight. And by adjusting with water, solid content 25%, viscosity 400cps
Was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 110 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 7
It was 3 kgf, which was inferior to those of Examples 7 to 9. The initial adhesive strength (shear adhesive strength) is 0.40 kg / cm when the compression time is 6 seconds.
^2, was 2.27 kg / cm ² at 1.44 kg / cm ^2, 10 seconds 8 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 3.

Comparative Example 24 Polyamide epichlorohydrin was prepared by adding 90 parts by weight of starch (15% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 7. , Clay as inorganic filler (30% slurry) and boric acid (3%
Aqueous solution) was added in the same manner as in Example 7,
It was 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight. And by adjusting with water, solid content 25%, viscosity 450cps
Was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 128 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 0 kgf. The initial adhesive strength (shear adhesion) is, 0.22 kg at compression time is 6 seconds ^{/ cm 2, 0.98kg / cm 2} , 10 in 8 seconds
It was 1.99 kg / cm ^{2 in} seconds, which was inferior to Examples 7 to 9. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. Needed. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. The results are also shown in Table 3.

Comparative Example 25 Polyamide epichlorohydrin was prepared by adding 0.5 part by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 7. , Clay as inorganic filler (30% slurry) and starch (15%)
Aqueous solution) was added in the same manner as in Example 7,
It was 2.0 parts by weight, 125 parts by weight and 50 parts by weight. And by adjusting with water, solid content 25%, viscosity 500cps
Was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 124 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 4 kgf. The initial adhesive strength (shear adhesion) is, 0.32 kg at compression time is 6 seconds ^{/ cm 2, 1.18kg / cm 2} , 10 in 8 seconds
It was 2.07 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, with hot water at 40 ° C, it took 50 hours for both paper pieces to peel and fall, and for boiling water, 1.2 hours for both paper pieces to peel and fall. It was inferior to Examples 7-9. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 3.

Comparative Example 26 Polyamide epichlorohydrin was prepared by adding 6.0 parts by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 7. , Clay as inorganic filler (30% slurry) and starch (15%)
Aqueous solution) was added in the same manner as in Example 7,
It was 2.0 parts by weight, 125 parts by weight and 50 parts by weight. And by adjusting with water, solid content 25%, viscosity 500cps
Was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 118 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 4 kgf. The initial adhesive strength (shear adhesion) is, 0.54 kg at compression time is 6 seconds ^{/ cm 2, 1.54kg / cm 2} , 10 in 8 seconds
It was 2.42 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and drop with warm water at 40 ° C, and for boiling water to take 2 hours or more for both paper pieces to peel off and fall. did. The viscosity increase rate as an evaluation of the viscosity stability over time was 3.8 times, and
It was inferior to 9. The results are also shown in Table 3.

[0114]

[Table 3]

Next, Examples 10 to 12 show adhesive compositions in which a predetermined amount of polyamide epichlorohydrin, an inorganic filler, dextrin, and boric acid were added to a vinyl acetate resin emulsion. In addition, comparative objects for Examples 10 to 12 are shown as Comparative Examples 27 to 34.

<Example 10> 2.0 parts by weight of polyamide epichlorohydrin were added to 100 parts by weight of a resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 1, and clay (30% slurry) was used as an inorganic filler. ) 125
Parts by weight, dextrin (15% aqueous solution) 50 parts by weight, boric acid (3% aqueous solution) 2.5 parts by weight, respectively,
By adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition had a ring crush strength of 125 kgf under normal conditions and a humidity resistance strength of 89 kgf when cured in an atmosphere of 50 ° C. × 90% RH. The initial adhesive strength (shear adhesive strength) is 0 when the compression time is 6 seconds.
^{67kg / cm 2, 2.48kg / cm} 2 at 8 seconds at 1.55kg / cm ^2, 10 seconds
Met. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. Table 4 shows the results
It is described together.

Example 11 When polymerizing the vinyl acetate resin emulsion in Example 10, the amount of acrylic acid was 0.5 part by weight with respect to 100 parts by weight of vinyl acetate monomer. Further, the compounding amount of polyamide epichlorohydrin was 0.8 part by weight with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion. Furthermore, 90 parts by weight of clay (30% slurry), 40 parts by weight of starch (15% aqueous solution), boric acid (3% aqueous solution) as an inorganic filler, relative to 100 parts by weight of the resin content of the vinyl acetate resin emulsion.
By adding 1.2 parts by weight each and adjusting with water, an adhesive composition having a solid content of 24.5% and a viscosity of 460 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 120 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 2 kgf. The initial adhesive strength (shear adhesion) is, 0.70 kg at compression time is 6 seconds ^{/ cm 2, 1.60kg / cm 2} , 10 in 8 seconds
It was 2.52 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 4.

<Example 12> When polymerizing the vinyl acetate resin emulsion in Example 10, the amount of acrylic acid was set to 4.5 parts by weight with respect to 100 parts by weight of the vinyl acetate monomer. Further, the compounding amount of polyamide epichlorohydrin was set to 4.6 parts by weight with respect to 100 parts by weight of the resin content of the obtained vinyl acetate resin emulsion. In addition, 165 parts by weight of clay (30% slurry) as an inorganic filler per 100 parts by weight of the resin content of the vinyl acetate resin emulsion,
By adding 65 parts by weight of dextrin (15% aqueous solution) and 4.7 parts by weight of boric acid (3% aqueous solution) and adjusting with water, an adhesive composition having a solid content of 26.5% and a viscosity of 560 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 131 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 9
It was 1 kgf. The initial adhesive strength (shear adhesion) is, 0.49 kg at compression time is 6 seconds ^{/ cm 2, 1.41kg / cm 2} , 10 in 8 seconds
It was 2.42 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and fall with hot water at 40 ° C, and for boiling water, two hours for both paper pieces to peel off and fall. It took more time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.5 times. The results are also shown in Table 4.

<Comparative Example 27> When a vinyl acetate resin emulsion was polymerized in the same manner as in Example 10, the amount of acrylic acid blended was 100 parts by weight of the vinyl acetate monomer.
It was 0.05 part by weight. Further, the compounding amount of polyamide epichlorohydrin was set to 0.3 part by weight based on 100 parts by weight of the obtained vinyl acetate resin emulsion. Furthermore, 125 parts by weight of clay (30% slurry) as an inorganic filler, based on 100 parts by weight of the vinyl acetate resin emulsion resin content,
By adding 50 parts by weight of dextrin (15% aqueous solution) and 2.5 parts by weight of boric acid (3% aqueous solution), and adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 120 kgf under normal conditions and a temperature of 50 ° C.
Moisture resistance strength when cured in an atmosphere of × 90% RH is 8
It was 2 kgf. The initial adhesive strength (shear adhesion) is, 0.65 kg at compression time is 6 seconds ^{/ cm 2, 1.62kg / cm 2} , 10 in 8 seconds
It was 2.55 kg / cm ² in seconds. Furthermore, in the water resistance evaluation test, in warm water at 40 ° C, it took 72 hours or more for both paper pieces to peel and fall, but in boiling water, the time for both paper pieces to peel and fall 1 minute, and Example 10
It was significantly inferior to ~ 12. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.3 times. Table 4 shows the results
It is described together.

Comparative Example 28 Clay (30% slurry), which is an inorganic filler, was not added to 100 parts by weight of the resin content of the vinyl acetate resin emulsion obtained in the same manner as in Example 10. , Polyamide epichlorohydrin,
Dextrin (15% aqueous solution) and boric acid (3% aqueous solution) were added in the same proportions as in Example 10, respectively.
It was 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight. And by adjusting with water, solid content 25%, viscosity 400cps
Was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 104 kgf under normal conditions, 50 ° C x 90% RH.
As the humidity resistance strength when cured in the atmosphere of 70 kgf,
All were inferior to Examples 10-12. The initial adhesive strength (shear adhesive strength) is 0 when the compression time is 6 seconds.
^{74kg / cm 2, 2.61kg / cm} 2 at 8 seconds at 1.65kg / cm ^2, 10 seconds
Met. Furthermore, in the water resistance evaluation test, with warm water at 40 ° C, it took 72 hours or more for both paper pieces to peel and fall, and for boiling water, the time for both paper pieces to peel and fall was 2 hours or more. It took time. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. Table 4 shows the results
It is described together.

<Comparative Example 29> Clay (30% slurry), which is an inorganic filler, was added to 200 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10. In the same manner as in Example 10, the addition ratios of polyamide epichlorohydrin, dextrin (15% aqueous solution) and boric acid (3% aqueous solution) were 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight, respectively. And by adjusting with water, solid content 25.5%,
An adhesive composition having a viscosity of 550 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 130 kgf in the normal state and 50 ° C ×
90k as the moisture resistance strength when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion) is a 1.84 kg / cm ² at 0.98 kg / cm ^2, 10 seconds compression time of 6 seconds at 0.28 kg / cm ^2, 8 seconds, compared with Examples 10 to 12 Was inferior. Furthermore, in the water resistance evaluation test, with warm water of 40 ° C., it took 72 hours or more for both paper pieces to peel off and fall, and for boiling water, the time for both paper pieces to peel off and fall It took more than 2 hours. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. Table 4 shows the results
It is described together.

Comparative Example 30 The addition ratio of clay (30% slurry), which is an inorganic filler, to 60 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10 was 60%. In the same manner as in Example 10, the addition ratios of polyamide epichlorohydrin, dextrin (15% aqueous solution) and boric acid (3% aqueous solution) were 2.0 parts by weight, 50 parts by weight and 2.5 parts by weight, respectively. And by adjusting with water, solid content 25.5%,
An adhesive composition having a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 106 kgf in the normal state and 50 ° C ×
71k as the humidity resistance when cured in an atmosphere of 90% RH
gf and all were inferior compared with Examples 10-12. Also, the initial adhesive force (shear adhesive force) has a compression time of 6
2.40kg seconds at 0.51kg / cm ^2, 8 seconds at 1.43kg / cm ^2, 10 seconds
/ Cm ² . Furthermore, in the water resistance evaluation test,
With warm water at 40 ° C., it took 72 hours or more for both paper pieces to peel and fall, and for boiling water, two hours for the paper pieces to peel and fall. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.4 times. The results are also shown in Table 4.

<Comparative Example 31> The addition ratio of dextrin (15% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10 was adjusted.
With 30 parts by weight, the addition ratios of polyamide epichlorohydrin, clay as inorganic filler (30% slurry) and boric acid (3% aqueous solution) were 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight, respectively, as in Example 10. It was made into a weight part. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 400 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 105 kgf in the normal state and 50 ° C ×
Moisture resistance of 70k when cured in an atmosphere of 90% RH
gf and all were inferior compared with Examples 10-12. Also, the initial adhesive force (shear adhesive force) has a compression time of 6
2.29kg seconds at 0.43kg / cm ^2, 8 seconds at 1.47kg / cm ^2, 10 seconds
/ Cm ² . Furthermore, in the water resistance evaluation test,
With warm water at 40 ° C., it took 72 hours or more for both paper pieces to peel and fall, and for boiling water, two hours for the paper pieces to peel and fall. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.2 times. The results are also shown in Table 4.

<Comparative Example 32> 90 parts by weight (15% by weight) of dextrin was added to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10.
Aqueous solution), and the addition ratios of polyamide epichlorohydrin, clay (30% slurry) as an inorganic filler and boric acid (3% aqueous solution) were 2.0 parts by weight, 125 parts by weight and 2.5 parts by weight, respectively, as in Example 10. Part and Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 450 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 126 kgf in the normal state and 50 ° C ×
88k as humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion) is a 1.95 kg / cm ² at 1.00 kg / cm ^2, 10 seconds compression time of 6 seconds at 0.24 kg / cm ^2, 8 seconds, none Example 10 It was inferior to 12. Furthermore, in the water resistance evaluation test, 40
With warm water of ℃, it took 72 hours or more for both paper pieces to peel and fall, and for boiling water, two paper pieces took 2 hours for peeling and fall. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.5 times. The results are also shown in Table 4.

Comparative Example 33 Polyamide epichlorohydrin was prepared by adding 0.5 part by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10. The addition ratios of clay (30% slurry) and dextrin (15% aqueous solution) as inorganic fillers were 2.0 parts by weight, 125 parts by weight and 50 parts by weight, respectively, as in Example 10. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 125 kgf in the normal state and 50 ° C ×
86k as humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.08 kg / cm ² at 1.18 kg / cm ^2, 10 seconds at 0.32 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, with hot water at 40 ° C, it took 60 hours for both paper pieces to peel and fall, and for boiling water, 1.6 hours for both paper pieces to peel and fall. It was inferior to Examples 10 to 12. The viscosity increase rate as an evaluation of the viscosity stability over time was 1.1 times. The results are also shown in Table 4.

Comparative Example 34 Polyamide epichlorohydrin was prepared by adding 6.0 parts by weight of boric acid (3% aqueous solution) to 100 parts by weight of the resin component of the vinyl acetate resin emulsion obtained in the same manner as in Example 10. The addition ratios of clay (30% slurry) and dextrin (15% aqueous solution) as inorganic fillers were 2.0 parts by weight, 125 parts by weight and 50 parts by weight, respectively, as in Example 10. Then, by adjusting with water, an adhesive composition having a solid content of 25% and a viscosity of 500 cps was obtained.

The performance of the obtained adhesive composition was evaluated as described above. This adhesive composition has a ring crush strength of 121 kgf in the normal state and 50 ° C ×
83k as the humidity resistance when cured in an atmosphere of 90% RH
It was gf. The initial adhesive strength (shear adhesion), the compression time was 2.39kg / cm ² at 1.50 kg / cm ^2, 10 seconds at 0.55 kg / cm ^2, 8 seconds 6 seconds. Furthermore, in the water resistance evaluation test, it took 72 hours or more for both paper pieces to peel off and drop with warm water at 40 ° C, and for boiling water to take 2 hours or more for both paper pieces to peel off and fall. did. The viscosity increase rate as an evaluation of the viscosity stability over time was 3.5 times, and the viscosity was increased in Examples 10-12.
Was inferior to. The results are also shown in Table 4.

[0138]

[Table 4]

[0139]

As described above, the adhesive composition of the present invention is
The vinyl acetate resin emulsion is provided with hot water resistance by the action of the carboxyl group and polyamide epichlorohydrin which is a water-soluble epoxy resin, and by the action of the inorganic filler and PVA added to the vinyl acetate resin emulsion, The adhesive film has high strength and excellent initial adhesive strength. In addition, boric acid provides excellent initial adhesion and water resistance. Therefore, when a cardboard is manufactured by winding a cardboard around a metal core, it is preferably used to bond the adjacent side edges of the cardboard spirally wound around the metal core to each other. Moisture resistance and pressure resistance are significantly improved.

Also, by adding carboxyl group-modified PVA, starch or dextrin in place of PVA, the same effects can be obtained respectively, and they can be suitably used and produced in the production of paper tubes. The moisture resistance and pressure resistance of the paper tube are also significantly improved.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C09J 103: 02 105: 02)

Claims (3)

[Claims] 1. A carboxyl group-containing monomer is added in an amount of 0.1 to 5.0 parts by weight to 100 parts by weight of a vinyl acetate monomer.
0.5 to 5.0 parts by weight of polyamide epichlorohydrin, 80 to 170 parts by weight of an inorganic filler, and 1.0 to 100 parts by weight of a resin component of a vinyl acetate resin emulsion obtained by emulsion polymerization in the presence of a protective colloid. An adhesive composition comprising 5.0 parts by weight of boric acid and 35 to 70 parts by weight of at least one selected from polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, starch and dextrin. 2. The adhesive composition according to claim 1, which is used for adhering adjacent side edge portions of the cardboard when the cardboard is wound around a mandrel to manufacture a paper tube. 3. A paper tube, characterized in that the adhesive composition according to claim 1 is manufactured by adhering adjacent side edge portions of a cardboard wrapped around a mandrel.