阅读说明：本技术 帘式涂布不干胶标签水溶性胶水的制备工艺 (Preparation process of water-soluble glue for curtain type coated non-setting adhesive label ) 是由 王壮鹏 蔡建涛 于 2021-09-06 设计创作，主要内容包括：本申请提供了帘式涂布不干胶标签水溶性胶水的制作工艺及其应用,其包含环保生物表面活性剂鼠李糖脂或十二烷基聚氧乙烯醚以及流变助剂BYK-410。本申请的胶水能有效改善帘式涂布稳定性,减少调整和停机带来的电力浪费和废水污染；配合水溶性离型剂,组成了环保且高质量的不干胶生产工艺。(The application provides a preparation process and application of water-soluble glue for a curtain type coating non-setting adhesive label, which comprises an environment-friendly biosurfactant rhamnolipid or dodecyl polyoxyethylene ether and a rheological additive BYK-410. The glue can effectively improve the curtain type coating stability, and reduce the electric power waste and the waste water pollution caused by adjustment and shutdown; the water-soluble release agent is matched to form the production process of the non-setting adhesive with environmental protection and high quality.)

1. A curtain type water-soluble glue for coating self-adhesive labels is characterized by comprising a surfactant and a rheological aid.

2. The curtain coated self-adhesive label glue of claim 1, wherein the rheological aid is selected from the Bick BYK series rheological aids.

3. The curtain coated self-adhesive label glue of claim 2, wherein the rheological additive is a BYK-410 rheological additive.

4. The curtain coating sticker label glue according to any one of claims 1 to 3, wherein the surfactant is sodium dodecyl sulfate in combination with rhamnolipid or dodecyl polyoxyethylene ether.

5. Curtain coated self-adhesive label glue according to any of the claims 1-4, wherein the curtain coated self-adhesive label glue consists of: methyl methacrylate, butyl acrylate, ethyl acrylate, acrylic acid, hydroxymethyl acrylamide, sodium dodecyl sulfate, ammonium persulfate, surfactant and rheological aid.

6. The curtain coated self-adhesive label glue of claim 5, wherein the curtain coated self-adhesive label glue consists of the following components: methyl methacrylate: 40 parts of butyl acrylate: 35 parts of ethyl acrylate: 22 parts of acrylic acid: 8 parts of hydroxymethyl acrylamide: 3 parts of sodium dodecyl sulfate: 2 parts of ammonium persulfate: 0.8 part, deionized water: 60 parts, 1 part of rhamnolipid and 1 part of BYK-4102 parts.

7. The application of the surfactant and the rheological additive in preparing curtain type adhesive label glue.

8. The use of claim 7, wherein the rheology aid is a pycnic BYK-410 rheology aid and the surfactant is sodium dodecyl sulfate complexed rhamnolipid or dodecyl polyoxyethylene ether.

9. Curtain coating method of self-adhesive label glue, characterized in that a curtain coating self-adhesive label glue according to any of claims 1-8 is used.

10. A self-adhesive label characterized in that it comprises a curtain coated self-adhesive label glue according to any one of claims 1-8.

Technical Field

The application relates to the field of adhesive label manufacturing and the field of glue manufacturing, in particular to curtain type coating adhesive label water-soluble glue and application thereof.

Background

The self-adhesive label is widely applied to the fields of medicine, daily chemicals, logistics and daily life, and is one of special papers which are most widely applied at present (according to the statistics of the pressure-sensitive adhesive label association, the annual output of China reaches or even exceeds 50 hundred million square meters at present). The self-adhesive label consists of base paper, a release coating, a glue coating, a surface material and the like. Compared with the stated paper and release agent, the glue and the coating mode thereof are more concerned factors in research and production in the self-adhesive label.

The glue types for the self-adhesive label mainly comprise hot melt glue, solvent glue, water-based glue and the like. The application range of the hot melt adhesive is limited, although the application range of the solvent adhesive is the best, the components such as organic solvents in the adhesive are not friendly to the environment and have higher price, and the main problem of the water-based adhesive is that the adhesive performance is insufficient, particularly under the adverse conditions of low temperature, water stain, oil stain and the like.

Compared with roll coating, slit coating and other methods, curtain coating is the fastest glue coating method, and has good performances in uniformity, stability and the like. However, curtain coating has high requirements on glue and operation level, and various curtain instability situations are easy to occur if the curtain is not proper, and the subsequent machine halt and adjustment not only waste a large amount of time and electric energy, but also increase the generation of waste water and waste materials.

Therefore, the need for improving the water-soluble glue of the self-adhesive label and the coating method is continuously existed in the application.

Disclosure of Invention

The applicant researches the causes of instability phenomenon in curtain coating, particularly the surface tension of glue and the rheological property under high shear, tries to improve the instability phenomenon in coating by using a surfactant and a rheological additive, and finds that the addition of the surfactant rhamnolipid or dodecyl polyoxyethylene ether and the rheological additive BYK-410 can effectively improve the stability of curtain coating; in addition, the use of the environment-friendly biosurfactant rhamnolipid can not only improve the curtain coating stability, but also effectively improve the initial adhesive property of the self-adhesive label product.

In one aspect, the present application provides a curtain coated self-adhesive label glue comprising a surfactant and a rheological aid.

Further wherein the rheological aid is selected from the BYK series of rheological aids.

Further, the rheological additive is ByK-410 rheological additive.

Further, the surfactant is sodium dodecyl sulfate matched rhamnolipid or dodecyl polyoxyethylene ether.

Further, the curtain type coating self-adhesive label glue consists of the following components: methyl methacrylate, butyl acrylate, ethyl acrylate, acrylic acid, hydroxymethyl acrylamide, sodium dodecyl sulfate, ammonium persulfate, surfactant and rheological aid.

Further, the parts of each component are methyl methacrylate: 40 parts of butyl acrylate: 35 parts of ethyl acrylate: 22 parts of acrylic acid: 8 parts of hydroxymethyl acrylamide: 3 parts of sodium dodecyl sulfate: 2 parts of ammonium persulfate: 0.8 part, deionized water: 60 parts, 1 part of rhamnolipid and 1 part of BYK-4102 parts.

In another aspect, the present application provides the use of a surfactant and a rheological aid in preparing a curtain coated self-adhesive label glue.

Furthermore, the auxiliary variable agent is a Pico BYK-410 rheological aid, and the surfactant is sodium dodecyl sulfate matched with rhamnolipid or dodecyl polyoxyethylene ether.

In another aspect, the present application provides a curtain coating method of a self-adhesive label glue, wherein the above glue is used.

On the other hand, the application provides a self-adhesive label, wherein contain above-mentioned glue.

The glue in the application is not limited to the specific formula listed in the embodiment, and other glues, particularly water-soluble glue, can also be added with a surfactant and a rheological aid to form the technical scheme of the application.

The reagent in the application is not limited to specific manufacturers, and products of all manufacturers with corresponding labels meeting the requirements of papermaking and glue can be adopted.

Drawings

Fig. 1 is a diagram showing an example of a typical heel (ferse) phenomenon occurring in coating.

Detailed Description

Rhamnolipids, a Sichuan trison organism, type R90;

dodecyl polyoxyethylene ether: shanghai Huayi;

rheological additive BYK-410, Germany Bike;

methyl methacrylate, butyl acrylate, ethyl acrylate, acrylic acid, hydroxymethyl acrylamide, sodium dodecyl sulfate and ammonium persulfate are conventional domestic varieties;

base paper and plain matte paper facestock were made by melting glass company;

the release agent is a solvent-free environment-friendly release agent of Dongguan Hongfeng silicon material Co., Ltd, and 5 rolls of the release agent are coated on base paper;

small/experimental curtain coater, original electromechanical devices of denna, ltd, CHTB-02.

EXAMPLE 1 glue formulation

The basic formula of the water-based glue is a formula which is verified by the applicant after long-time use: methyl methacrylate: 40 parts of butyl acrylate: 35 parts of ethyl acrylate: 22 parts of acrylic acid: 8 parts of hydroxymethyl acrylamide: 3 parts of sodium dodecyl sulfate: 2 parts of ammonium persulfate: 0.8 part, deionized water: 60 parts. The preparation method comprises the steps of preparing a pre-emulsion and adding an initiator to carry out emulsion polymerization.

For the modification of the glue formulation, the applicant has tried a large number of different formulations, only a few representative examples of which are selected in the present document:

1, glue water: the above basic formulation;

glue 2: the basic formula + 1 part of rhamnolipid;

glue 3: the basic formula and 2 parts of dodecyl polyoxyethylene ether;

glue 4: the basic formula is + BYK-4102 parts;

glue 5: the basic formula comprises 1 part of rhamnolipid and 1 part of BYK-4102 parts.

Example 2 improvement of curtain coating stability by glue

The minimum curtain flow (i.e., no curtain failure, T-shaped curtain or curtain holes) for each glue formulation was tested using the mini/pilot curtain coater described above and the results are shown in the following table:

TABLE 1 minimum curtain flow for various glue formulations

The result shows that the minimum curtain flow can be effectively reduced by adding rhamnolipid or dodecyl polyoxyethylene ether on the basis of SDS, and the operation space and the overall coating stability of other factors in the glue coating process of the self-adhesive label paper are increased. No obvious effect is achieved by using BYK-410 alone, but BYK-410 and rhamnolipid or dodecyl polyoxyethylene ether have obvious further improvement effect on the effects of the two.

The maximum coating weight at a coating speed of 300 m/min was tested without heel (ferse) phenomena

TABLE 2 maximum coating weights for various glue formulations

Glue formula	Maximum coating weight g/m2
		Glue 1	48.7
Glue 2	58.5
		Glue 3	52.2
Glue 4	53.8
		Glue 5	64.9

According to previous studies, the cause of the heel (ferse) phenomenon is mainly due to the change of shear rheological characteristics at high curtain speed ratio, and the specific mechanism is not completely clear. The results show that the addition of the rhamnolipid surfactant effectively increases the maximum coating amount, and the cooperation of BYK-410 and rhamnolipid further increases the effect of rhamnolipid, so that the coating can be potentially improved, particularly the stability under high coating speed.

Example 3 practical application case

In the technology of earlier experiments, a technical scheme that 1 part of rhamnolipid and BYK-4102 parts are added into aqueous glue is selected to be used for an actual coated paper adhesive label production line, in the running test time of 2 weeks, the average production efficiency (production time-unplanned downtime/production time) of a machine is improved to 96.2% from 94.5%, and the wastewater amount is reduced by about 28%.

Furthermore, we have found that the addition of rhamnolipid and YK-410 improves the coating stability without deteriorating the basic adhesive properties of stickers (quick stick force, 24 hour final stick force, picking, low temperature properties) and even to some extent improves the quick stick of the sticker paper product from the previous 14.5N to 16.2N, (loop method, see FINAT/global Sticker manufacturers Association' standard: 200mmx25mm test strips at 25 degrees Celsius, 50% RH for 4 hours; removal of backing material, glue sticking out side to side into a loop; loop end 10mm vertical placement after clamping of the tensile force device clamp, recovery at the same rate immediately after applying the loop to the test plate at 25mmx25mm area at 300 mm/min; record the maximum force during separating the loop and test plate, 5 times average).