JPH0645386B2 - Water-soluble adhesive injection device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ejection device for ejecting liquid particles containing a water-soluble adhesive.

(Prior Art and Problems Thereof) So-called aerosol type adhesives in which an adhesive is ejected as liquid particles from an ejection device are conventionally known. But,
Such an aerosol type adhesive is generally rubber-based and water-insoluble. Therefore, even if the adhesive interface bonded with such an adhesive is peeled off again with water, the peeling is impossible, which is one of the problems depending on the use conditions.

On the other hand, as the water-soluble resin, various ones such as polyvinyl alcohol, carboxymethyl cellulose, sodium alginate and the like are known, but such a water-soluble resin shows an extremely high viscosity even in a low-concentration solution. It is said that it is unsuitable as a type adhesive, and conventionally, an aerosol type adhesive using a water-soluble resin has not yet been developed.

However, if an aerosol-type adhesive that uses a water-soluble resin is developed, the adhesive interface can be easily peeled off again with water, and the solidified adhesive can be eluted and removed. It is clear that a product very suitable for sticking papers such as the above can be obtained.

(Problem of the Invention) An object of the present invention is to develop an aerosol-type adhesive agent using a water-soluble resin.

(Means for Solving the Problems) The present inventor has completed the present invention as a result of various studies to solve the above problems.

That is, according to the present invention, an organic solvent solution of polyethyloxazoline is pressure-sealed together with a propellant in a hermetic container having a spray nozzle, and the polyoxazoline concentration in the solution is 10% by weight or more. A water-soluble adhesive ejecting device is provided.

Polyethyloxazoline used as an adhesive in the present invention is a water-soluble polymer obtained by ring-opening polymerization of 2-ethyloxazoline, and is soluble in many organic solvents. This is conventionally used as an adhesive or the like for plastics.

In the present invention, this polyethyloxazoline is used as an organic solvent solution and is pressurized and sealed together with a propellant in a hermetic container (aerosol can) equipped with a spray nozzle. According to the research conducted by the present inventor, such an aerosol type adhesive has a high concentration of water-soluble resin,
It has been found to have excellent jetting properties. That is, polyethyloxazoline has a low solution viscosity even when used at a high concentration of 10% by weight or more with respect to an organic solvent, has excellent fluidity, and is clean when ejected from a nozzle of an ejector. It can be ejected as atomized particles and does not cause the stringing phenomenon of the resin. In addition, polyethyloxazoline is a propellant such as LPG (liquefied petroleum gas) and L.
Although it is not dissolved in NG (natural liquefied gas), it can be dissolved uniformly when mixed as the above-mentioned organic solvent solution. Therefore, the use of surfactants for dispersion is not required. Moreover, when the polyethyloxazoline solution is mixed with a propellant, the viscosity of the solution is further lowered, and on the contrary, the fluidity is improved and the injection characteristics tend to be improved.

In the polyethyloxazoline solution used in the present invention,
The average molecular weight of the polyethyloxazoline is 10,000 to 10
The concentration is 0,000, preferably 50,000 to 500,000, and the concentration thereof is 10% by weight or more, preferably 20% by weight or more. When the polyethyloxazoline concentration is lower than the above range, the adhesive content in the injection gas becomes low and the adhesive strength becomes poor, which is not preferable. The upper limit of the polyethyloxazoline concentration is not particularly limited and varies depending on the organic solvent used, but it is generally about 30% by weight. Naturally, it has compatibility with polyethyloxazoline to improve the performance as an adhesive, and as a plasticizer or tackifier, for example, polyethylene glycol, polypropylene glycol, polyacrylic acid soda, polyacrylamide (methylolation)
One or two or more water-soluble substances such as can be added if necessary. As the organic solvent for dissolving polyethyloxazoline, alcohols such as ethanol, isopropanol and methanol, ketones such as methyl ethyl ketone and acetone, and various polar solvents such as ethylene glycol, propylene glycol, dioxane and methyl acetate can be used. Boiling point 60-130
It is preferable to use an organic solvent at 0 ° C., particularly an alcohol such as ethanol or isopropanol.

As the propellant, a liquefied hydrocarbon gas such as propane, n-butane, isobutane, n-pentane, isopentane or a mixture thereof is used. Generally, liquefied petroleum gas or liquefied natural gas is preferably used. Also, fluorocarbons such as florodichloromethane can be used.

In the present invention, the use ratio of the propellant to the polyethyloxazoline solution is 100% polyethyloxazoline solution.
The proportion is 10 to 50 parts by weight, preferably 15 to 40 parts by weight, based on parts by weight. In the present invention, since the polyethyloxazoline solution is uniformly mixed with the propellant, it is possible to efficiently inject the polyethyloxazoline solution with a small amount of the propellant, and to obtain a very efficient injecting device. You can

(Advantages of the Invention) Since the adhesive injection device of the present invention uses a water-soluble adhesive as the adhesive, the adhesive interface can be easily peeled off with water, and the adhesive solidified on the solid surface can be used. The agent can be removed by elution with water. Therefore,
The adhesive injection device of the present invention is suitable for adhering posters, photographs, labels and the like.

(Examples) Next, the present invention will be described in detail with reference to Examples.

Example 1 Polyethyloxazoline (average molecular weight: about 50,000) was dissolved in isopropanol to obtain a polyethyloxazoline concentration.
A 20 wt% solution (viscosity at 25 ° C .: 125 cps) was prepared. Next, 300 g of this solution was filled in an aerosol can having an inner volume of 500 ml, and further 60 g of a propellant (liquefied butane) was filled to obtain an adhesive injection device. When the solution was sprayed from the spraying device thus obtained, the solution was sprayed as fine mist-like particles and no stringing phenomenon was observed. Also,
When a high-quality paper was attached to a glass plate using this adhesive injection device, it was confirmed that the high-quality paper was strongly adhered to the glass plate. Further, when water was sprayed onto the high-quality paper to wet it and the high-quality paper was peeled off, the high-quality paper was peeled off cleanly from the glass plate.

Example 2 An adhesive injection device was made in the same manner as in Example 1 except that the use ratio of the solution and the propellant was changed variously, and its injection characteristics were examined. In the case of this device, 100 parts by weight of the solution It was confirmed that good injection can be obtained by using 10 parts by weight or more of the propellant.

Example 3 An adhesive injection device was prepared in the same manner as in Example 1 except that the concentration of polyethyloxazoline in the solution was variously changed, and the injection properties and the adhesion of the injection product were tested as follows. The results are shown in Table 1.

(Injection characteristics) When the solution was ejected together with the propellant from the ejecting device, it was visually observed whether the solution was sprayed as fine mist-like particles without stringing. The case of being atomized and sprayed was judged as “good”, and the case of causing stringing was judged as “poor”.

(Adhesiveness) When two pieces of high-quality paper are adhered using a jetting device and then peeled off easily without peeling, the adhesiveness is “poor” and peeling is difficult, and when tearing occurs on the high-quality paper The adhesiveness was judged as “good”.

Claims (3)

[Claims] 1. An organic solvent solution of polyethyloxazoline, which is pressurized and enclosed together with a propellant in a hermetic container equipped with a spray nozzle, wherein the polyethyloxazoline concentration in the solution is 10% by weight or more. Characteristic water-soluble adhesive injection device. 2. The propellant is a liquefied hydrocarbon gas.
Equipment. 3. The apparatus according to claim 1, wherein the proportion of the propellant used is 10 to 50 parts by weight based on 100 parts by weight of the polyethyloxazoline solution.