JPH08302329A - Quick adhesive excellent in initial adhesion - Google Patents

Abstract

PURPOSE: To provide a quick adhesive improved in wet tack and roll leveling properties in quick bonding and hence excellent in initial adhesion by adding a specific additive(s) to an aqueous emulsion containing a hydroxylated polymer as a component. CONSTITUTION: This adhesive is prepared by adding at least one additive (e.g. titanium hydroxide) selected from among Congo red, antimonic acid, its salt compounds, and compounds of Cu, Al, Ti, Zr, Sn, V and Cr to an aqueous emulsion (e.g. vinyl acetate polymer emulsion) containing a hydroxylated polymer (e.g. PVA) as a component. The amount of the hydroxylated polymer is preferably 1-50 pts.wt. (hereinafter merely pts.), particularly 5-30 pts. per 100 pts. of the base polymer, and the amount of the additive(s) is preferably 2-20 pts., particularly 5-14 pts. per 100 pts. of the hydroxylated polymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high speed adhesive for adhering adherends, particularly paper, at a high speed, and more particularly to an aqueous emulsion high speed adhesive for paper.

[0002]

2. Description of the Related Art Various types of high-speed adhesives have been developed, but adhesives having higher-speed adhesive properties are required as the production speed increases. For example, on a cigarette tipping paper attachment machine, 4,000 per minute
Adhesion speed of 0 or more, that is, linear velocity of 10 m / min or more is required, and since the air permeability of the adherend paper is also large, it is not possible to perform high-speed adhesion with a conventional adhesive. It is possible.

That is, in the above-described high-speed bonding machine, the rotation speed of the coating roll becomes extremely large, and the shearing force applied to the adhesive becomes large. However, it has been confirmed by experiments that the conventional emulsion-type adhesive has a reduced viscosity under high shear and that the thixotropic adhesive has a weak initial adhesive force in high-speed adhesion. In addition, when the air permeability of the adherend paper becomes large, the water in the emulsion is permeated into the paper and the polymer particles are fused (dried) to give a wet tack, thereby giving an initial adhesive force. There is a limit.

Further, in addition to the demand for improving the initial adhesive strength, mechanical stability such as roll leveling property, adhesive scattering property, storage stability, and re-emulsification property are important in a high speed adhesive machine.

No conventional emulsion type adhesive completely satisfies both the above initial adhesive strength and mechanical properties. For example, JP-A-61-72074 describes that by adding boric acid to an aqueous emulsion containing polyvinyl alcohol, it is possible to impart dilatancy to the fluidity and use it as a high-speed adhesive.

However, even if boric acid is used, the initial adhesiveness at the time of high-speed bonding is not satisfactory, and the roll leveling property, which is greatly affected by the fluidity, is also unsatisfactory.

[0007]

The present inventor has noticed that the fluidity of a high-speed adhesive is an important factor in the high-speed adhesive, and it is an extremely simple method without significantly changing the conventional composition, and the fluidity at the time of high-speed adhesive is improved. The present invention has been completed by succeeding in improving the initial adhesiveness.

Therefore, the object of the present invention is to provide a novel adhesive composition which can be used for adherends, particularly for adhesion at a linear velocity of 10 m / min or more, or for adhesion requiring a large wet tack. To do.

[0009]

A high-speed adhesive according to the present invention contains a polymer containing a hydroxyl group as a component, and an aqueous emulsion containing vanadic acid and its salt compound, congo red, antimonic acid and its salt compound, Cu, Al,
It is characterized by being a high-speed adhesive having excellent initial adhesiveness, which is obtained by adding at least one of Ti, Zr, Sn, V and Cr compounds. By further adding the above-mentioned additives, the glass plate is tilted at 30 ° with respect to the horizontal, the inclined glass plate is brought into contact with the contact position where it contacts the horizontal base, and each adhesive is applied uniformly to 10 mil using an applicator. 15 seconds after placing the paperboard on the measuring instrument after placing the paperboard horizontally and applying the adhesive. Roll 10 metal balls from a distance of 30 cm on the glass plate, and when the balls stop on the paperboard, the horizontal length from the contact position is 2
It is characterized by being 0 cm or less. When the wet tack of this ball is 20 cm or less, sufficient adhesion performance as the above high-speed adhesive is exhibited.

The high speed adhesive of the present invention is mainly used for adhesion of paper which requires high speed adhesion, for example, adhesion of cigarette chip paper, but it can also be used for other high speed adhesion which requires large wet tack. Yes, and more
Obviously, it can be applied to articles other than paper.

The emulsion of the present invention may be based on the conventionally known vinyl acetate polymer-based aqueous emulsion, ethylene-vinyl acetate vinyl copolymer-based aqueous emulsion, and vinyl acetate copolymer-based aqueous emulsion, which are used for paper adhesion. it can. Since these emulsions are well known and do not form the essence of the present invention, the details are omitted. The point is that a known emulsion type adhesive of the above type may be used in an appropriate composition and concentration depending on the properties of the adherend.

The first feature of the present invention is that each of the above emulsions contains a polymer having a hydroxyl group, and 2 to 10 parts by weight, preferably 5 to 1 part by weight per 100 parts by weight of this polymer.
The point is to add 4 parts by weight of the following additives.

Vanadic acid and its salt compounds, Congo red, antimonic acid and its salt compounds, Cu, Al,
Ti, Zr, Sn, V, Cr Compound Examples of the polymer having a hydroxyl group include polyvinyl alcohol and HEC.

The above-mentioned polymer containing a hydroxyl group may be an emulsifier which is usually used when polymerizing the emulsion and / or a polymer which is added later when the emulsion is prepared into an adhesive.

The amount of the hydroxyl group-containing polymer is preferably 1 to 50 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of the base polymer, and stable when the amount is 1 part by weight or less. If it exceeds 50 parts by weight, the viscosity will rise too much and the workability will be poor. It is necessary that the amount of the additive is 2 to 20 parts by weight, preferably 5 to 14 parts by weight, based on 100 parts by weight of the hydroxyl group-containing polymer. If the amount of the additive is 2 parts by weight or less, tack is insufficient and no effect is obtained, and if it is 20 parts by weight or more, the fluidity is deteriorated and the workability is deteriorated. This addition amount varies depending on the adhesion speed, and can be appropriately selected within the above-mentioned addition amount range.

The above-mentioned additives are preferably added to the emulsion after polymerization when adjusting the adhesive.

The emulsion type adhesive of the present invention contains other commonly used additives such as a plasticizer, a surfactant,
Antifoaming agents, preservatives and the like can be added. In particular, a plasticizer is preferably added to lower the MFT, and the amount thereof is generally 10 to 40 PHR, and this amount can be appropriately changed depending on the type of emulsion used.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.

Example 1 Congo red was added to the vinyl acetate polymer-based aqueous emulsion shown in Table 1-1 as a polymer having a hydroxyl group so as to be 2 to 20 parts by weight based on 100 parts by weight of polyvinyl alcohol. . The properties and adhesive properties (evaluated by ball wet tack and roll leveling property) of the emulsion thus obtained are shown in Hail No. 2-1. The properties of the emulsion vary depending on the amount of Congo red added (2 to 20 parts by weight). In Table 2, the properties of the emulsion are shown as an upper limit-lower limit or an average value in order to clarify the effect of improving the adhesive properties of Congo Red according to the present invention.

Example 2 Ethylene-shown in Table 1-2
Titanium hydroxide was added as a hydroxyl group-containing polymer to a vinyl acetate copolymer-based aqueous emulsion so that the amount was 2 to 20 parts by weight based on 100 parts by weight of polyvinyl alcohol. The properties and adhesive properties (evaluated by ball wet tack and roll leveling property) of the emulsion thus obtained are shown in Table 2-2. The properties of the emulsion vary depending on the amount of titanium hydroxide added (2 to 20 parts by weight). In Table 2, the properties of the emulsion are shown as an upper limit-lower limit or an average value in order to clarify the effect of improving the adhesive properties of titanium hydroxide according to the present invention.

(Example 3) [0021] Polyvinyl alcohol 1 as a polymer containing a hydroxyl group containing ammonium vanadate in an aqueous emulsion of vinyl acetate copolymer shown in 3 of Table 1.
2 to 20 parts by weight was added to 00 parts by weight. Table 2-3 shows the property adhesive properties (evaluated by ball wet tack and roll leveling property) of the emulsion thus obtained. The properties of the emulsion change depending on the amount of ammonium vanadate added (2 to 20 parts by weight). In Table 2, the properties of the emulsion are shown as an upper limit-lower limit or an average value in order to clarify the effect of improving the adhesive properties of the ammonium vanadate according to the present invention. Each evaluation item for evaluating the adhesive property in Table 2 was measured as follows. [Ball Wet Tack] The glass plate is tilted at an angle of 30 ° with respect to the horizontal, and the inclined glass plate is brought into contact with the contact point where it contacts the horizontal base, and each adhesive is applied with an applicator for 10 m
The paperboard uniformly applied to the il was placed horizontally, and after application of the adhesive, 15 seconds after being set in the measuring instrument, No.
Ten metal balls were rolled from a distance of 30 cm on the glass plate, and the horizontal length (cm) from the contact position when the ball stopped on the paperboard was indicated. In this measurement, the horizontal length of the adhesive having a strong wet tack becomes short.

[Roll Leveling Property] The transfer roll was submerged about half in a trough containing the adhesive, and the transfer state of the adhesive transferred from the transfer roll to the coating roll was visually evaluated. O indicates that the adhesive was uniformly transferred to the coating roll, Δ indicates that the adhesive was almost uniform but not perfect, and X indicates that the transfer was uneven.

As is apparent from the results shown in Table 2, when the amount of the additive added is 2 to 20 parts by weight, preferably 5 to 14 parts by weight, well-balanced adhesive properties are obtained.

[0024]

[Table 1]

[Table 2]

[0025]

The high speed adhesive of the present invention can improve the wet tack and roll leveling property during high speed adhesion by adding vanadic acid and the like to the base polymer.

Claims (2)

[Claims] 1. An aqueous emulsion containing a polymer having a hydroxyl group as a component, vanadic acid and its salt compound, congo red, antimonic acid and its salt compound, Cu,
A high-speed adhesive having excellent initial adhesiveness, which is obtained by adding at least one of Al, Ti, Zr, Sn, V and Cr compounds. 2. A paperboard in which a glass plate is tilted at an angle of 30 ° with respect to the horizontal, the inclined glass plate is in contact with a contact position where it contacts a horizontal base, and each adhesive is uniformly applied to 10 mils using an applicator. Is placed horizontally, and after application of the adhesive, 15 seconds after being set in the measuring device, No. Claims, wherein 10 metal balls are rolled from a distance of 30 cm on the glass plate, and the horizontal length from the contact position when the ball is stopped on the paperboard is 20 cm or less. The high-speed adhesive according to item 1.