KR100657027B1 - Adhesive package tapes with temperature-sensive functions - Google Patents

Abstract

The present invention provides an improved packaging adhesive tape having a temperature sensing function for visually checking a temperature environment in a distribution process without opening a box containing a temperature sensitive product, and coated with a variable temperature pigment on its front surface, The adhesive composition composed of a water-soluble acrylic emulsion, aniline or isocyanate-based crosslinking agent and rosin paper is transferred to the back side, so that the temperature environment in the moving process can be checked even if only the container in which the product is accommodated. At least two times, the peel force is to provide a very useful functional packaging tape with amazing properties improved at least six times.

Temperature Sensing, Temperature Pigment, Water Soluble Acrylic Emulsion, Aniline Crosslinking Agent, Rosin Paper

Description

Improved package tapes with temperature-sensive functions

The present invention is a packaging adhesive tape having a temperature sensing function, in particular irreversible thermochromic inorganic pigments are applied to the front surface, at the same time compared to the conventional adhesive composition on the back about 2 times or more (tack) and about 6 times or more peeling force The present invention relates to a package adhesive tape to which an adhesive composition for improved adhesive tape having a peel strength is transferred.

Recently, adhesive tapes for packaging have been used in large quantities for box packaging for accommodating various products including temperature-sensitive objects. When the goods shipped or delivered are temperature sensitive goods, unsatisfactory results often occur when the goods are handled in a distribution environment above a certain temperature.

Irreversible Temperature Discoloration Inorganic pigments are widely known as pigments having the property of discoloring and being irreversibly maintained under a certain temperature. The present inventors have completed the present invention under the conviction that by applying the properties of the irreversible thermochromic inorganic pigment to the adhesive tape for packaging, it is possible to immediately obtain the effect of determining the product error due to the excess of temperature in the distribution process, On the other hand, the present inventors determined that in order for the adhesive tape with a temperature sensing function to be practical, it is necessary to improve the instantaneous adhesive force and the peeling force seen in the conventional adhesive tape, and improved the adhesive composition to be transferred to the adhesive tape backside. As a result, the present invention has been completed.

For the understanding of the present invention, the concept and adhesion of the following colors are briefly described. Color can be quantified using the Lab coordinate system. The Lab coordinate system is a three-dimensional coordinate system represented by the L * axis representing the degree of light and dark, the a * axis representing the degree of red and green, and the b * axis representing the degree of yellow and blue. Therefore, the degree of discoloration is measured by the color difference ΔE, and ΔE may be calculated as the distance to one point in the three-dimensional space of the L *, a *, and b * axes. Adhesion in tape is a kind of adhesion, which is strongly semi-permanently adhered only by applying a small pressure at room temperature for a short time, and it can stand on a hard smooth surface.Adhesive properties include peel strength and holding strength. power and tack. The instantaneous adhesive force is defined as the force adhering to the adherend in a short time, and the peeling force is defined as the force against the peeling adsorbed on the adherend over time.

In designing an adhesive composition for an adhesive tape, several attempts have been made to optimize the instantaneous adhesive force and the peeling force. According to Korean Patent Registration No. 153356 (Adhesive composition for producing an adhesive tape), in order to solve the problem of weakening of adhesive strength due to bleeding phenomenon from a plasticizer used in the prior art, an aqueous acrylic resin emulsion is mainly used as a monomer or a polyhydric alcohol monomer. The composition to which the polymer is added is disclosed. According to Korean Patent Registration No. 229530 (Method for producing an aqueous acrylic emulsion-based adhesive tape), an oxazole polymer or an epoxy acrylic resin is used as a crosslinking agent in a method for preparing a composition having better adhesive strength and peeling force than an organic solvent type adhesive tape. A method of adopting is proposed. In addition, according to Korean Patent Publication No. 2004-6119 (a water-soluble acrylic emulsion type pressure-sensitive adhesive composition), a pressure-sensitive adhesive composition containing ethylene glycol diglycidyl ether as an adhesive excellent in water resistance, heat resistance and cold resistance has been disclosed.

According to the preceding data, by applying an aqueous acrylic resin emulsion as a component of the adhesive composition, it is possible to find a common advantage that the adhesive suitable for the regulation of volatile organic compounds (VOC), which has been a problem in the conventional organic solvent type adhesives. It was possible, but still did not obtain an optimized adhesive composition. In particular, the physical properties of the adhesive pressure-sensitive adhesive tape on the market is not satisfactory, the need for a pressure-sensitive adhesive composition excellent in peel force and instantaneous adhesive force that can overcome this has emerged.

The present invention provides a packaging adhesive tape for packaging a box containing a temperature sensitive product, the improved packaging adhesive tape having a temperature sensing function for visually confirming whether the box is handled above a specified temperature without opening the box. To provide,

Still another object of the present invention is to disclose a packaging adhesive tape having a temperature sensing function to which an adhesive composition having an optimum instantaneous adhesive force and a peeling force is transferred.

The object is achieved by a packaging adhesive tape wherein an irreversible thermochromic inorganic pigment is applied to the front surface, and a crosslinking agent selected from a water-soluble acrylic resin, an amine type and an isocyanate type, and a pressure sensitive adhesive composition containing rosin.

Hereinafter, the configuration of the present invention to be described in detail through the manufacturing method.

First, irreversible temperature discoloring inorganic pigments (hereinafter referred to as temperature pigments) are commercially available inorganic pigments that turn blue at 70 ° C. When the product is left under direct sunlight or high temperature during the transportation of the product, the internal color of the packaged product is higher than the external temperature, and thus, the pigment discolored at 70 ° C. is selected from the judgment that it is sufficiently practical, but the technique of the present invention Of course, thought is not limited to this.

The adhesive composition transferred to the back side of the adhesive tape having a temperature sensing function will be described.

A water-soluble acrylic pressure-sensitive adhesive (hereinafter referred to as HT-A) having a solid content of 40% as a basic resin was obtained from Jaesung Co., Ltd., South Korea. The acrylic pressure-sensitive adhesive is mainly a polymer obtained by acrylic copolymerization of C2-C12 aliphatic alcohol, and a small amount of copolymerization of monomers having a polar group including acrylic acid and acrylamide, but the base resin of the pressure-sensitive adhesive composition achieved by the present invention is not limited thereto. No. For example, the water-soluble acrylic pressure-sensitive adhesive is about 50 parts by weight of 2-hexylethyl acrylate monomer, about 30 parts by weight of butyl acrylate monomer, about 15 parts by weight of ethyl acrylate monomer and about 5 parts by weight of acrylic acid. After mixing water to the part, a small amount of an emulsifier and an aqueous acrylic emulsion of about 50% by weight of a solid content polymerized by adding ammonium persulfate as a reaction accelerator and heating may be equally applied. In addition, 1-3 parts by weight of a DOP (dioctyl phthalate) plasticizer may be added to the base resin. The crosslinking agent was obtained from the above company as an aniline derivative (hereinafter referred to as JS-50) or an isocyanate derivative (hereinafter referred to as CAT-80). When the degree of crosslinking becomes too large, the polymer hardens, and when receding, the adhesive strength decreases, therefore, proper composition ratio specification is important. The water-soluble acrylic resin having an acrylic group which is a basic resin is crosslinked by a crosslinking agent and has a three-dimensional structure. The tackifier resin is usually a solid oligomer of several hundred to thousands of amorphous oligomer at room temperature as a liquid or solid thermoplastic resin, in consideration of compatibility with the adhesive resin, a solid rosin resin (hereinafter referred to as D1000) was selected. It is speculated that the tackifier resin functions as a kind of coagulation tuberculosis function to bind the adhesive polymer chains more firmly.

The amount of change in the color component is measured by using a color difference meter to measure the amount of change from the reference value when the pigment is coated. The colorimeter reads the color of the captured part through the component analysis of three-dimensional coordinates L *, a *, and b *, where L * is closer to 100 and white when a sign increases positively. And b * is yellow when the sign is positively increased. The tack measurement of the adhesive composition was used by connecting a stainless steel cylinder (probe) to a texture analyzer (Model: Micro stable system TA-XT2i), and the tack was a probe moving speed (3.0mm / s) and contact time (1 second). Since it is influenced by the peeling rate (8.5mm / s), the variables were controlled and compared to each other by measuring the tack of the tapes (temperature 23.5 ° C, humidity 48.5%). Peel force was measured by connecting a tensile tester to the TA-XT2i probe instead of 180 ° peel force. At this time, the width of the specimen was 2.5cm, the pulling length was 80mm, the peeling rate was measured to 8.5mm / s.

Example 1

The alternating pigment was mixed with PVA (Polyvinyl Alcohol) aqueous solution at a ratio of about 80:20 (volume ratio) to prepare a homogeneous mixture. The PVA aqueous solution was mixed with PVA and water at about 70:30 (volume ratio) and heated to prepare a complete aqueous solution. The PVA aqueous solution acts as a solvent for the pigment, thereby increasing the coating efficiency of the pigment.

The pigment was coated on the entire surface of the OPP film and dried to measure a reference color difference using a color difference meter to obtain a reference value L * = 89.93, a * =-0.29 and b * =-1.34, based on a temperature of 40 ° C. Color difference (ΔE) and Δb * were measured while increasing the temperature from 65 ° C to 89 ° C by 2 ° C (Table 1).

ΔE and Δb * measurements over temperature Temperature Δb * △ E Temperature Δb * △ E 40 ℃ 0.03 -0.11 75 ℃ 1.10 3.31 50 ℃ 0.04 0.47 77 ℃ 2.28 3.60 60 ℃ 0.05 0.37 79 ℃ 4.82 3.59 65 ℃ 0.09 0.07 81 ℃ 9.49 3.98 67 ℃ 0.13 0.53 83 ℃ 14.59 4.77 69 ℃ 0.14 1.02 85 ℃ 25.43 8.79 71 ℃ 0.50 3.20 87 ℃ 39.21 12.24 73 ℃ 0.97 3.22 89 ℃ 42.50 13.66

The temperature at which discoloration began to occur is around 73 ° C, and as the temperature increases, discoloration is accelerated, and it can be confirmed that the discoloration pigment can be usefully detected when the pigment is applied to the front surface of the adhesive tape for packaging.

Hereinafter, an embodiment of the pressure-sensitive adhesive composition to be transferred to the packaging adhesive tape back.

Example 2

In order to select the appropriate content range of the crosslinking agent, 0.25 g, 0.50 g, 0.75 g of JS-50 was added to 50 g of HT-A, and stirred by hand at room temperature for 10 minutes. After stirring, the mixture of the prepared pressure-sensitive adhesive and crosslinking agent was coated on the film to measure the adhesive property, and the composition ratio mixture showing the highest adhesion was obtained (Table 2).

Measurement results of basic resin and crosslinking agent mixture HA-A (50 g) Tack (g) Peel Strength (g) JS-50 (0.25g) 1962.2 1039.1 JS-50 (0.50g) 1549.5 851.3 JS-50 (0.75g) 1479.1 686.1

From the results of Table 2, the basic resin and the crosslinking agent composition ratio was found that 0.5g of the crosslinking agent per 100g of the basic resin is the optimum ratio. Therefore, 1 part by weight or more of the crosslinking agent based on 100 parts by weight of the base resin can harden the composition, and it is not preferable, and a very small amount of crosslinking agent of 0.01 parts by weight or less lowers the adhesiveness of the composition. Therefore, the optimum crosslinking agent composition ratio required in the present invention is 0.01-1 part by weight based on 100 parts by weight of the base resin.

In addition, by replacing the JS-50 with an isocyanate-based crosslinking agent (CAT-80), the same repetitive experiment results as in Example 2 showed the same physical properties as those of the aniline-based crosslinking agent. It was confirmed that one could be selected.

In order to improve the performance of the adhesive tape, a rosin paper is added so that the polymer chain constituting the pressure sensitive adhesive layer is not loosened. The rosin paper may act as an impurity in relation to the base resin, and thus, through Example 3 to specify an optimal composition ratio, The composition of rosin land was calculated.

Example 3

After mixing D1000 0g, 5g, 10g, 15g, 20g in HA-A 50g, JS-50 0.25g composition for 30 minutes with a stirrer at room temperature, it was applied to a film to measure the physical properties (Table 3). At this time, since the D1000 is solid, a solution dissolved 1: 1 with toluene was added to the base resin and the crosslinking agent mixture.

Physical properties of rosin paper added HT-A (50g) + JS-50 (0.25g) + Tack (g) Peel Strength (g) D1000 0g 1962.2 936 * 1039.1 ** D1000 5g 2908.5 1035.2 * 1272.2 ** D1000 10g 1986.1 1068.6 * 1520.3 ** D1000 15g 810.0 n / a n / a D1000 20g 366.6 n / a n / a

*: Paper adherend, **: stainless steel adherend

n / a: Tape self-damage, impossible to measure

Through Table 3, the optimum values of the tack and peel strengths are between 5g-10g, and when the rosin paper is added excessively, the tape adhesive strength becomes weak or broken.

In order to confirm the preferred amount of rosin paper, the composition was prepared by subdividing the range, and then measured physical properties.

Example 4

In the same manner as in Example 3, D1000 was subdivided into 4g, 6g, and 8g to prepare a composition to measure physical properties (Table 4).

HT-A (50g) + JS-50 (0.25g) + Tack (g) Peel Strength (g) D1000 4g 2199.7 1356.3 D1000 6g 2203.6 2950.4 D1000 8g 2382.2 3172.4

Comparative example

Commercially available packing tapes (Seotong Co., Ltd., transparent OPP tape) were obtained to measure the tack and peel strength, and compared with the physical properties of the composition of the present invention.

Tack Peel Strength paper stainless steel Commercial OOP 1115.6 529.3 910.0 Improved composition (average) 2382.2 3172.4

It can be seen that the instantaneous adhesive force and the peeling force of the packaging tape coated on the back of the adhesive composition are improved by about 2 times and about 6 times, respectively, compared to the tapes of the same application.

The present invention provides a packaging adhesive tape having a temperature sensing function for visually checking a temperature environment in a distribution process without opening a box containing a temperature sensitive product, and coated with an alternating pigment on the front side and the rear side. A water-soluble acrylic emulsion is employed as the base resin, 0.01 to 1 parts by weight of aniline or isocyanate-based crosslinking agent is added, and 10 to 20 parts by weight of a rosin resin is applied, and a pressure-sensitive adhesive composition is applied, and a box for storing or opening the product can be opened. Applied to the storage container, it is possible to check the temperature environment in the moving process even by looking at the container in which the product is accommodated.In addition, it has an amazing property of at least 2 times improvement in the instantaneous adhesive force and at least 6 times the peeling force as compared to the conventional packing tape properties. To provide a very useful functional packaging tape.

Claims (4)

On the front is coated with an alternating pigment of irreversible function mixed with a PVA aqueous solution, 100 parts by weight of a water-soluble acrylic emulsion; 0.01 to 1 part by weight of aniline or isocyanate crosslinking agent; And an improved packaging adhesive tape having a temperature sensing function, to which a pressure-sensitive adhesive composition containing 10 to 20 parts by weight of rosin paper is transferred. delete  The water-soluble acrylic emulsion according to claim 1, wherein the water-soluble acrylic emulsion comprises 50 parts by weight of 2-hexylethyl acrylate monomer, 30 parts by weight of butyl acrylate monomer, 15 parts by weight of ethyl acrylate monomer, and 100 parts by weight of a mixture composed of 5 parts by weight of acrylic acid. Improved aqueous packaging with a temperature sensing function, characterized in that it is an aqueous acrylic emulsion of 50% by weight of solids which is polymerized by adding ammonium persulfate as an emulsifier and a reaction accelerator. Adhesive tape. delete