JP3782155B2 - Attaching the thermal label - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of sticking a heat-sensitive adhesive label to an adherend such as a container, and more particularly to a method of activating and sticking a heat-sensitive adhesive by the heat of the adherend.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there is a container in which a label coated with a heat-sensitive adhesive that is activated and bonded by heating to an object to be bonded, such as a synthetic resin container, is provided.
As a method for attaching such a label, there is a method in which a heat-sensitive adhesive is activated and bonded by the heat of the adherend having a predetermined temperature by heating the adherend such as a container.
[0003]
[Problems to be solved by the invention]
However, since the heat-sensitive adhesive label is deprived of the heat of the adherend when the heat-sensitive adhesive label is brought into contact with the adherend such as a container having a temperature higher than the activation temperature of the heat-sensitive adhesive, In some cases, the activation of the heat-sensitive adhesive was insufficient and the adhesion was weakened.
In particular, this problem occurred in a container with a thin object and in winter when the label was cold.
In addition, it was considered to blow-mold a synthetic resin container and attach the heat-sensitive label to a warm container immediately after the blow-molding. Since it was discharged | emitted, the temperature of a container was only about 60-80 degreeC, and activation of a heat sensitive adhesive became inadequate.
[0005]
This invention makes it a subject to provide the thermal label sticking method from which favorable adhesion | attachment is obtained, without the activation of a thermosensitive adhesive becoming insufficient as mentioned above.
[0006]
[Means for Solving the Problems]
The present invention is, Yes in order to solve the above problems, after heating the heat-sensitive labels to a temperature at slightly lower than the activation temperature of the heat-sensitive adhesive (-1~-30 ℃), the activated temperature or higher Then, the thermosensitive adhesive is activated and stuck by pressing against a container immediately after blow molding with a surface temperature of 60 to 80 ° C. Also, after preheating the heat-sensitive label to a temperature of 35 to 55 ° C. without activating the heat-sensitive adhesive of the heat-sensitive label, immediately after blow molding having a temperature equal to or higher than the activation temperature and a surface temperature of 60 to 80 ° C. The heat-sensitive adhesive is activated and stuck by pressing the container. For this reason, when a heat sensitive label contacts a container, activation of a heat sensitive adhesive is fully performed and favorable adhesion | attachment is performed.
[0007]
Moreover, since the temperature which heats a thermosensitive label before making it contact with a container is comparatively low temperature, it can stick without causing deformation | transformation, such as a curl and shrinkage | contraction, to a label.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
The heat-sensitive label 1 used in the present invention is a heat-sensitive label having a printed layer 3 such as letters and designs formed on a label substrate 2 made of a synthetic resin film or the like and having adhesiveness with the surface of an object to be bonded such as a container 5. It is formed by applying the adhesive layer 4.
[0009]
The label substrate 2 is generally used for labels such as films made of various synthetic resins such as stretched or unstretched polypropylene, polyester, polyvinyl chloride, polyethylene, polystyrene, polyamide, and synthetic paper and paper formed from polyester and polyolefin resins. The substrate used.
[0010]
The printing layer 3 can be formed by known printing means such as gravure printing, screen printing, letterpress printing, etc., but when a transparent synthetic resin film is used for the label substrate 2, it is formed on the back by gravure printing. In addition, it is preferable to use a heat-resistant type of printing ink, such as a two-component curable urethane-based resin ink, so that the adhesive strength between the label substrate 2 and the printing layer 3 at the time of label sticking is stable. It is preferable.
[0011]
The heat-sensitive adhesive layer 4 is made of a hot-melt type that softens and melts when heated to produce adhesiveness, a delayed tack type that develops adhesiveness and maintains adhesive strength when heated, and the like. It can be selected according to the temperature.
[0012]
An example of the case where the heat-sensitive label 1 is attached using heat when a synthetic resin container is formed by blow molding will be described with reference to FIG.
Reference numeral 5 denotes a container immediately after being melt-extruded from polypropylene, polyethylene or the like, blow-molded and discharged from a molding die.
The surface temperature of the container 5 is about 60 to 80 ° C.
The container 5 is transferred in the direction of arrow A while being held by a transfer device (not shown).
Reference numeral 6 denotes a label magazine for supplying the thermal label 1.
After the thermal label 1 is delivered from the label magazine to the label sticking drum 7, it is adsorbed on the peripheral surface of the label sticking drum 7 with the heat sensitive adhesive layer 4 facing outward, and the sticking drum 7 rotates. It is transferred in the direction (arrow B).
A heating device 8 such as hot air or infrared radiation is provided outside the drum 7.
The heat-sensitive label 1 is heated to a temperature 1 to 30 ° C. lower than the activation temperature of the heat-sensitive adhesive 4, preferably 5 to 20 ° C. lower than the activation temperature of the heat-sensitive adhesive 4 in the process of being adsorbed and transferred to the sticking drum 7.
[0014]
Thus, the thermal label 1 heated to a temperature lower by 1 to 30 ° C. than the activation temperature of the thermal adhesive 4 is transferred by the sticking drum 7 and is brought into contact with and pressed against the surface of the container 5, and the container has. The heat-sensitive adhesive is activated and bonded by heat.
At this time, since the heat-sensitive adhesive 4 is not activated until it comes into contact with the surface of the container, there is little possibility of embedding bubbles between the label and the surface of the container.
[0015]
In addition, when the label substrate is formed from a synthetic resin film such as polypropylene, the heating temperature during the process of transferring the thermosensitive label 1 (before contacting the container) It is preferable to heat to 35 to 55 ° C. so that it does not deform due to shrinkage.
[0017]
However, since the container immediately after blow molding is thin at a relatively low temperature and does not have a sufficient amount of heat, the method of the present invention can be preferably used.
[0018]
Furthermore, in the method for sticking the heat-sensitive label of the present invention, it is not a condition to provide a heating device outside the sticking drum as shown in FIG. 1 described above, and heating may be performed from the inside of the sticking drum. . Moreover, it is not a condition to use a sticking drum.
[0019]
【The invention's effect】
As described above, according to the method for attaching a heat-sensitive label of the present invention, the heat-sensitive adhesive of the heat-sensitive adhesive label can be sufficiently activated even if the amount of heat of the container is small. In addition, since the pre-heating of the heat-sensitive label is lower than the activation temperature of the heat-sensitive adhesive, even if the label base material is a polypropylene film having no heat resistance, it is stuck without being bent or contracted. can do.
[Brief description of the drawings]
FIG. 1 is a plan view illustrating the present invention. FIG. 2 is an explanatory view of an adherend (container) to which a thermosensitive label is attached.
3 is a cross-sectional view of the main part of FIG.
[Explanation of symbols]
1: Thermal label 2: Label base material 4: Thermal adhesive 5: Container 7: Label sticking drum 8: Heating device

Claims (2)

A thermosensitive label having a thermosensitive adhesive coated on the back surface has a temperature equal to or higher than the activation temperature of the thermosensitive adhesive, and the surface temperature is 60-80 ° C. In the sticking method of the heat-sensitive adhesive label to be stuck, the heat-sensitive label is one in which the heat-sensitive adhesive is activated and bonded by the heat of the container immediately after the blow molding , and the heat-sensitive label is attached to the heat-sensitive label. After preheating to a temperature 1 to 30 ° C. lower than the activation temperature of the adhesive, the heat-sensitive adhesive is activated by pressing against a container immediately after blow molding having a temperature equal to or higher than the activation temperature of the heat-sensitive adhesive. A method for sticking a heat-sensitive label, characterized by sticking. A thermosensitive label having a thermosensitive adhesive coated on the back surface has a temperature equal to or higher than the activation temperature of the thermosensitive adhesive, and the surface temperature is 60-80 ° C. In the sticking method of the heat-sensitive adhesive label to be stuck, the label base of the heat-sensitive label is formed from a synthetic resin film, and the heat-sensitive adhesive is activated and adhered by the heat of the container immediately after the blow molding. After preheating the thermal label to a temperature of 35 to 55 ° C. without activating the thermal adhesive of the thermal label, the container is immediately after blow molding having a temperature higher than the activation temperature of the thermal adhesive. A method for attaching a heat-sensitive label, wherein the heat-sensitive adhesive is activated by being pressed and attached.

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