JP2003280527A - Label and labeled package - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a label which can suppress rising of a liquid level of the contents of a container during unsealing of its cap and a package which is fitted with this label to a synthetic resin bottle for sterile filling. <P>SOLUTION: The label is a shrink label to be attached to the outer peripheral surface of the body of a blind cylindrical container and to be secured by causing shrinkage under heating, in which the thermal shrinkage stress of the shrink label cooled after shrinkage under heating is below 2.5 MPa and the labeled package. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a label which is fitted on the outer peripheral surface of a body of a cylindrical container having a bottom, is heat-shrinked, and is tightened.
Also, the present invention relates to a labeled package. More specifically, the present invention relates to a label that can suppress a rise in the liquid level of the contents of the container when the cap is opened, and a labeled package for a synthetic resin bottle for aseptic filling.

[0002]

2. Description of the Related Art Conventionally, for filling and packaging beer, vitamin drinks, milk / milk drinks, juice, carbonated drinks, drinking water such as water and tea, or oil, seasonings, and various other liquid foods, Various types of plastic bottles, glass bottles, metal cans, etc. (hereinafter referred to as "containers") have been developed. Then, on the surface of these containers, for the purpose of protecting the containers, bundling, labeling, etc., the mouth of the containers,
BACKGROUND ART A shrink film (hereinafter also referred to as “heat-shrinkable film”) is known as a packaging material for rapidly covering or binding a part or all of a shoulder portion, a body portion, and the like. As a shrink wrapping method, for example, there is known a method in which a tubular or bag-shaped film is subjected to primary wrapping with some allowance, and then the film is shrunk to the outer peripheral surface of the container by hot air, steam or the like. . . Since the shrink wrapping can fit into any shape container such as a square shape, a round shape, and a gourd shape, the shape of the container can be widely selected. As shrink wrap, colorless shrink film or printed shrink film to add the function of displaying the product name, manufacturer name, contents, and design to the entire surface and sealing part of these containers is used. Packaging of containers is also practiced. Of the synthetic resin bottles with a bottomed cylindrical container as described above, the bottles to be filled in a hot state absorb the reduced pressure on the side surface of the bottle so that the bottle does not deform even if the internal pressure fluctuates after closing. A concave pressure reducing panel is provided for this purpose.

[0003]

However, when the polyester shrink label normally used for such a bottle is mounted so as to cover the above-mentioned pressure reducing panel portion, the label presses the bottom surface of the concave portion of the pressure reducing panel during heat shrinkage. When opening the cap, there is a problem that the liquid level of the contents rises or the contents overflow from the mouth. A technology to provide a shrink label made of polyester that has a vacuum panel and is attached to a hot-filled rectangular plastic container so that the liquid level of the content does not rise and the content does not overflow from the mouth when opening. Japanese Patent Laid-Open No. 2001-2122 discloses that, since the thickness of the bottle has been reduced recently, there is a problem that the liquid level rises even for labels other than polyester and the contents overflow from the mouth. .
Also, when hot filling the contents, the container is depressurized when the contents are cooled to room temperature, so the liquid level at the time of opening is relatively low, but after sterilizing the inner and outer surfaces of the container. When the contents are aseptically filled, such as aseptic filling, there is a problem that the contents overflow from the mouth because the liquid level at the time of opening is not lowered.

[0004]

In order to solve the above problems, the inventors of the present invention have conducted extensive studies and as a result, have found that a label capable of suppressing an increase in the liquid level of the contents of the container when the cap is opened, and an aseptic filling container. The present invention finds a labeled package for a synthetic resin bottle. INDUSTRIAL APPLICABILITY The present invention is a shrink label that is attached to the outer peripheral surface of a body of a bottomed cylindrical container and shrinks by heating and tightens, and the shrink label cooled after heating shrinkage has a shrinking stress of less than 2.5 MPa. It is related to a label characterized by being present. In the above, the heat shrinkage stress of the shrink label subjected to heat shrinkage at the heating temperature peak value of 45 to 150 ° C. and the processing time at the heating temperature peak value of 0.5 msec to 30 sec is less than 2.5 MPa. A featured label can be provided. Further, it is possible to provide a bell characterized in that the base material of the shrink label contains either a polyolefin resin or a cyclic olefin resin. Further, it is also possible to provide a labeled package in which the shrink label is mounted in a synthetic resin bottle and aseptically filled.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall view of a labeled wrapping body showing an embodiment of a mounting form in the present invention. As shown in FIG. 1, the synthetic resin bottle is composed of a mouth portion, a shoulder portion, a body portion, and a bottom portion, and is biaxially stretch blow molded. The blow-molded bottle is aseptically filled with the content liquid and is closed with a cap. The above-mentioned bottle has the label of the present invention printed on the bottle side of the label, and the label of the present invention covering from the bottom to the upper end of the shoulder is wrapped around the bottle.

The shrinking process of the label according to the present invention to the bottle can be divided as follows. (1) The heat-shrinkable synthetic resin film according to the present invention is formed into a tubular shape to cover the bottle. (2) The heat-shrinkable synthetic resin according to the present invention is melted by applying heat with a heater or the like. (3) The label is covered by tightening the bottle by the heat shrinkage stress of the label in which the melted portion is made of the heat shrinkable synthetic resin film. (4) If the temperature of the label decreases due to natural cooling and heat dissipation, the heat shrinkage stress also gradually decreases, and the heat shrinkage stress is 2.5M.
It decreases to less than Pa. (5) If the temperature of the entire label becomes uniform, the heat shrinkage stress is maintained at less than 2.5 MPa.

FIG. 2 is a graph showing the relationship between the heat shrinkage stress at the vertical axis and the heat shrinkage stress at a heating temperature of 95 ° C. for 20 seconds when the horizontal axis indicates time. As shown in Example 1 of FIG. 2, the characteristics of the material of the label according to the present invention include, for example, 0 second to 20 seconds when the heating time H is 20 (seconds) and the heating peak temperature is 95 ° C. Second (normal temperature 22 ℃ ~ heating peak temperature 95 ℃) is,
Thermal contraction stress rises rapidly from 0 MPa and peak value is 3
After reaching the MPa level, the heat shrinkage stress decreases from about 3 MPa for 20 seconds to 100 seconds (time to reach the heating peak temperature of 95 ° C to room temperature of 22 ° C), and after 100 seconds has elapsed (room temperature of 22 ° C). Is made of a material in which the temperature is constant and stable, but the heat shrinkage stress is also constant at about 1 MPa.

In the above graph, the heat shrinkage stress of the shrink label cooled after heat shrinkage is 2.5 MPa.
Any label can be used as long as the label has a property of being less than 1.5 MPa, and more preferably 1.5 MPa or less. As a result, among the labeled packages made of such a heat-shrinkable resin film, in particular, aseptic bottles having a higher liquid level than hot-filled bottles, after natural cooling and heat dissipation, at room temperature, the heat-shrinkable stress. Is less than 2.5 MPa, no excessive heat shrinkage stress is applied. Therefore, in order to suppress the rise in the liquid level due to the tightening of the label on the bottle, when opening the cap for aseptic bottles that have a higher liquid level than hot-filled bottles and bottles that are thin It is preferable because liquid spills are less likely to occur.

The shrinking process of a label having a heat shrinkage stress of 2.5 MPa or more to a bottle can be divided as follows. (1) The heat-shrinkable synthetic resin film is formed into a tubular shape to cover the bottle. (2) The heat-shrinkable synthetic resin according to the present invention is melted by applying heat with a heater or the like. (3) The label is covered by tightening the bottle by the heat shrinkage stress of the label in which the melted portion is made of the heat shrinkable synthetic resin film. (4) When the temperature of the label decreases due to natural cooling and heat radiation, recrystallization of the resin occurs, the heat shrinkage stress gradually increases, and the heat shrinkage stress increases to 2.5 MPa or more. (5) When the temperature of the entire label becomes uniform, the heat shrinkage stress also becomes constant at a value of 2.5 MPa or more, the force for tightening the label on the bottle becomes constant, and the shrinkage of the label stops.

As shown in Comparative Examples 1 and 2 of FIG. 2, the characteristics of the label material having a heat shrinkage stress of 2.5 MPa or more include, for example, a heating time H of 20 (seconds) and a heating peak temperature of 95 ° C. When heat-treated at 0 to 20 seconds (room temperature 22
In the period from ℃ to heating peak temperature of 95 ° C.), the heat shrinkage stress rises rapidly and reaches the heat shrinkage stress peak value, and after the peak value has passed, the heat shrinkage stress value gradually decreases, but 20 seconds to 100 seconds. At (heating peak temperature 95 ° C. to room temperature 22 ° C.), the heat shrinkage stress increases with decreasing temperature, and after 100 seconds (room temperature 22 ° C.) the temperature stabilizes at a constant level. Shrinkage stress is also 2.5P
It is made of a material held at a value of a or more.

For this reason, particularly in a package in which a label is shrunk on an aseptic bottle having a liquid level higher than that of a hot-filled bottle, the heat shrinkage stress is 2.5 MPa or more at room temperature after natural cooling and heat radiation. As a result, the force for tightening the bottle of the label becomes excessive, and the liquid level rises, so that liquid spillage easily occurs when opening the cap, which is not preferable.

The heat treatment time (second) in the flow direction and the width direction of the heat-shrinkable resin film in the present invention is 0.5.
The heating peak temperature is 50 or more msec to 30 sec.
℃ -150 ℃ is preferred, more preferably 7
It is 0 ° C to 100 ° C. When the heating peak temperature exceeds 100 ° C., the resin layer shrinks and the container is deformed when heated and brought into close contact with the bottle, which is not preferable. Further, uniform heat shrinkage is not applied to the label, and perforation occurs in the label, which is not preferable. Furthermore, the heating of the bottle undesirably modifies the components of the contents. When the heating peak temperature is less than 50 ° C., the heat shrinkage is not sufficient and the bottle cannot be completely or almost completely adhered to the outer peripheral surface of the bottle, or cannot be adhered to the outer surface at all, or Adhesive strength is extremely weak, resulting in an incomplete coating adhesion state, which is not preferable.

Examples of the label material having the above-described characteristic that the heat shrinkage stress has a smaller value at room temperature after natural cooling and heat radiation than at the value immediately after heating, for example, polypropylene film and low density polyethylene film. , Polyethylene films such as medium-density polyethylene film, high-density polyethylene film, and low-density linear polyethylene film, cyclic polyolefin film, polystyrene film, ethylene-α in which an appropriate number of short chain branches are introduced into a linear main chain -Olefin copolymer (as α-olefin, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, nonene-1, decene-1, dodecene-1, tetradecene-1, Octadecene-1,4-methylpentene-1,4-methylhexene-1,4,4-di 3 carbon atoms such as methylpentene-1
.About.20 .alpha.-olefin or a mixture thereof can be mentioned, and of these, .alpha.-olefin having 3 to 12 carbon atoms is preferable. ), 6 nylon film, polyamide film such as 6,6 nylon film, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-methyl acrylate copolymer, etc. Polyolefin film, chlorinated polyethylene, modified polyolefin film formed from a resin such as chlorinated polypropylene, film formed from a vinyl chloride-vinyl acetate copolymer resin,
An acrylic resin film or the like can be used. Further, these films may be laminated and used as a single layer or a multilayer film of two or more layers. Further, as the above-mentioned base material, either a uniaxially stretched film or a biaxially stretched film can be used. If necessary, an overcoat layer may be provided on the surface to prevent damage. The thickness of the substrate is not particularly limited, but is appropriately selected within a range that does not impair heat resistance at about 70 to 110 ° C., rigidity, mechanical suitability, appearance, etc., preferably 5 to 90 μm, and preferably 15 to 60 μm. desirable.

The stretching treatment of the heat-shrinkable film according to the present invention is carried out by using, for example, a tenter system or a tube system.
The film may be uniaxially stretched in the width direction (TD direction) of 1.5 to 8 times, preferably 4 to 5 times. In addition, if necessary, a stretching treatment can be performed at a low stretching ratio (for example, about 1.5 times or less) also in the direction [the film flow direction (MD direction)] orthogonal to the above direction. Further, after stretching, heat setting is usually performed by passing through a heating zone of about 60 to 90 ° C. for about 1 to 10 seconds. The film thus obtained has orientation in the main stretching direction and exhibits heat shrinkability in that direction.

The heat shrinkage rate of the heat shrinkable film according to the present invention is 8 to 80 in the TD direction (direction corresponding to the circumferential direction of the container) when the heat shrinkage rate when treated with hot water at 70 to 95 ° C. for 10 seconds. %, And preferably 45 to 75%. When the heat shrinkage rate is less than 8%, the shrinkage is insufficient when the synthetic resin bottle is mounted, and the shrink label cannot be closely attached to the bottle, which is not preferable. If the heat shrinkage exceeds 80%, the shrink label is distorted, which is not preferable. here,
The heat shrinkage is a value having a meaning of (dimension before heating-dimension after heating) / (dimension before heating) × 100.

The label according to the present invention may be provided with a printing layer on at least one surface, if necessary. As the printing layer constituted above, the entire surface of the heat-shrinkable synthetic resin film, or partially, gravure printing, flexographic printing,
The pattern is formed by using a known printing technique such as offset printing. As the ink used for the printing layer,
A commonly used ink that has adhesiveness to the heat-shrinkable synthetic resin film and has necessary resistance can be used. It is preferable to print with a gravure ink, which is an ink having high heat resistance. As the thickness of the printing layer,
Although not particularly limited, it is preferably about 1 to 10 μm,
About 5 μm is desirable. An OP varnish layer may be provided on the printed layer for the purpose of protecting it from damage such as rubbing due to external force.

In the label of the present invention, the heat-shrinkable synthetic resin film may optionally contain a lubricant, a filler, a heat stabilizer, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant,
You may add various additives, such as a coloring agent. On the surface of the heat-shrinkable synthetic resin film 5, in order to improve printability,
Conventional surface treatment such as corona discharge treatment, plasma treatment, flame treatment and acid treatment may be applied.

In the present invention, the label is made to be a heat-shrinkable synthetic resin film / printing layer (outside of the container) (inside the container), and the lower end and the upper end which are both ends thereof are overlapped, and then, A label composed of a tubular body can be produced by forming a seal portion by heat-sealing or pasting with an adhesive agent with the overlapped portion of the end portion as a joint portion. . The label of the present invention may be in the form of a tube.

A perforation for opening may be formed on the side surface of the labeled synthetic resin bottle according to the present invention from the upper end to the lower end. Further, two vertical perforations may be provided starting from the tab for opening the label (separation start portion), and the label can be easily broken by the perforations. In addition, the perforation is not limited to two, and it is possible to provide one or a plurality of three or more. The perforation is, for example, a method of forming a cut to a predetermined depth in the thickness direction of the packaging material by using a laser beam to form a disc-shaped blade in which a cut portion and a non-cut portion are repeatedly formed around the circumference. It can be applied by a method of pressing and forming. Further, the perforations can be provided at an appropriate stage in the process of manufacturing the label.

The material of the container (bottle), which is the adherend of the label in the present invention, is heat resistance (temperature 80) which is sufficient to withstand shrinking the label after filling the contents.
To 90 ° C.), and examples thereof include synthetic resin bottles. Examples of the resin constituting the synthetic resin bottle include vinyl polymers such as olefin polymers such as polyethylene (PE) resin and polypropylene (PP) resin, styrene polymers such as polystyrene, and polyethylene terephthalate (PET). Resin, polyester resin such as polybutylene terephthalate (PBT), and thermoplastic resin such as vinyl chloride resin can be mentioned. As a typical example, polyethylene terephthalate (P
ET) resin. The shape of the bottle is not limited to a synthetic resin bottle having a flat portion in the body, and is also a square type equipped with a decompression panel having a shape capable of absorbing the reduced pressure and suppressing the deformation of the bottle. The bottle is not limited to the synthetic resin bottle, and may be a normal round type, a square type, an octagonal type, or a gourd type that does not include a decompression panel.

The food and drink targeted for the contents of the container, that is, the food and the drink, are not particularly limited as long as they can be aseptically filled. Examples of food include rice, rice cake, tofu, cream, yogurt, jelly, bavarois, mousse, soup, sauce, vinegar, ketchup, mayonnaise,
Examples include various extracts. Also, as a beverage,
For example, carbonated drinks such as cola and cider, drinks containing fruit juice,
Acid drinks such as sports drinks, sterilized lactic acid bacteria drinks, lemon tea, tomato juice and vegetable juice (pH 4.6
), And low-acidic beverages (pH 4.6 or more) such as dairy products, coffee, cocoa, chocolate, teas, mixed tea, barley tea, soy milk, and mineral water.

In the present invention, the shrink label tubular body produced above is supplied to, for example, an automatic label mounting apparatus, cut into a required length, and then, for example, outside the container filled with contents. It is fitted to the surface, and then the container is passed through a shrink tunnel or the like to a predetermined temperature (for example, 60
(About ~ 200 ℃) hot steam, steam to be heated by steam and steam formed by condensation of steam, and radiant heat such as infrared rays are caused to highly shrink the shrink label in the circumferential direction,
The body of the container is covered with a shrink label. Therefore,
The labeled package of the present invention can be manufactured.

In the present invention, the label manufactured as described above is attached to the body portion of the bottle made of synthetic resin, so that the label retains an appropriate shrinkability and has an excessive shrink stress. When opening the cap without taking too much,
It is possible to obtain an excellent labeled package in which the liquid level of the contents does not rise.

Examples of shrink labels according to the present invention will be described below. (Example 1) As a heat-shrinkable synthetic resin film for shrink labels according to the present invention, a polyolefin film having a thickness of 50 µm was prepared.

(Experiment 1: Heat Shrinkage Stress Test) The heat shrinkable synthetic resin film of Example 1 was tested with a test width of 25 mm and a test length of 100 mm.
The sample was cut out so that Using a heat shrinkage stress tester (manufactured by Nichi Kogyo Co., Ltd., model: DN type stress tester), after setting the cut out sample on the tension detector,
An initial load of 0.25 kg / mm ² was applied and the length was kept constant. While heating this by 10 ° C. per minute in a heating furnace, the heater for contacting the sample is heated from room temperature to a set temperature, and when the contact heater temperature reaches the set temperature, the sample is kept in a temperature-holding state. The heater was contacted, the measurement of the heat shrinkage stress value was started, and the measurement was performed until the temperature returned to room temperature. In addition, the heat shrinkage stress value was written on a chart and measured with the zero point before contacting the heater. Equilibrium heat shrinkage stress (MPa) is calculated as the shrinkage stress value 100 seconds after the start of measurement.
And The measurement results are shown in Table 1.

A sample obtained by cutting Example 1 into a sample having a trial width of 25 mm and a trial length of 100 mm was carried out in the same manner as above except for the heating temperature, and the heating peak temperatures of 70 ° C. and 75
The heat shrinkage stress values were measured at 80 ° C., 80 ° C., 95 ° C., 110 ° C., 125 ° C., and 135 ° C., respectively. The measurement results are shown in Figure 3.
Shown in.

Comparative Example 1 As the heat-shrinkable synthetic resin film, a polyester resin film having a thickness of 45 μm (manufactured by Toyobo Co., Ltd., product name: S7542) was prepared. A sample was cut out from the above-mentioned heat-shrinkable synthetic resin film with the same dimensions as in Example 1, and the heating peak temperature was 60 ° C, 70 ° C, 75 ° C, 80 ° C, 95 ° C, 110 ° C by the same method.
The heat shrinkage stress values at 125 ° C. and 135 ° C. were measured, respectively.
The measurement results are shown in FIG.

Comparative Example 2 As the heat-shrinkable synthetic resin film, a polystyrene resin film having a thickness of 50 μm (manufactured by Mitsubishi Plastics, Inc., product name: DXL219-45) was prepared. A sample was cut out from the above heat-shrinkable synthetic resin film with the same dimensions as in Example 1, and the heating peak temperature was 60 ° C, 70 ° C, 75 ° C, 80 ° C, 95 ° C by the same method.
The heat shrinkage stress value at 110 ° C. was measured. The measurement results are shown in FIG.

A heat-shrinkable synthetic resin film of Example 1 was prepared. On top of that, as a pattern printing layer, Clios 950
Shiro (manufactured by The Inktech Co., Ltd.), plate depth 40μ
Gravure printing was performed using a halftone plate having a m of 175 lines.

Thereafter, the heat-shrinkable synthetic resin film obtained as described above was rewound into a roll. After cutting into a label sheet of a desired size, perforations having a width of 15 mm on both sides of the bonded portion, a cut portion length of 0.7 mm and a non-cut portion length of 1.4 mm intersect the shrinking direction. Two lines were applied in the direction. After that, the heat-shrinkable synthetic resin film is shrunk in the circumferential direction of the container (outside of the container) so that the polyolefin film / the pattern printing layer (inside of the container) are overlapped with each other. Then, the overlapping portion was heat-bonded with a welding seal to obtain a cylindrical shrink label continuous body. As a container, height is 208m
m, the diameter of the body was 62 mm, and the mouth having a diameter of 28 mm was formed.

Although not shown, the PET bottle in which 500 ml of the content (water) having a water temperature of 22 ° C. was aseptically filled and the cap was closed, and the obtained cylindrical shrink label continuum were supplied to an automatic label mounting device. After the shrink label was fitted on the outer surface of the bottle, it was heated with a steam heater at 60 ° C. for 20 seconds to shrink-fit. As a result, a shrink package having the shrink label provided from the upper end to the bottom of the neck of the container body was obtained.

After the shrink label of Example 1 was fitted on the outer surface of a bottle different from the above, the same procedure as above was carried out except for the heating peak temperature at which the bottle was heated. ℃, 95 ℃, 110 ℃, 125 ℃, 1
Each bottle was heated at 35 ° C. for 20 seconds, shrink-fitted, and the shrink-labeled package was provided with the shrink label provided from the upper end to the bottom of the neck of the container body.

The heat-shrinkable synthetic resin film of Comparative Example 1 was also subjected to the same heating peak temperature of 60 as in Example 1.
℃, 70 ℃, 80 ℃, 95 ℃, 110 ℃, 125 ℃, 1
Each bottle was heated at 35 ° C. for 20 seconds and shrink fitted. As a result, a label-equipped packaging body having the shrink label provided from the upper end to the bottom of the neck of the bottle body was obtained.

Also for the heat-shrinkable synthetic resin film of Comparative Example 2, the heating peak temperature of 60 was obtained by the same method as in Example 1.
Each bottle was heated at 0 ° C, 70 ° C, 80 ° C, 95 ° C, and 110 ° C for 20 seconds and shrink-fitted. as a result,
A labeled package having the shrink label provided from the upper end to the bottom of the neck of the bottle body was obtained.

In the evaluation of the shrink labels of Example 1 and Comparative Examples 1 and 2 above, the peak value of the heating temperature was 60 to 135.
After heating at ℃ for 20 seconds, after natural cooling and heat dissipation, room temperature 22 (℃)
The heat shrinkage stress was measured. The results are shown in Table 1.

(Experiment 1: Results of heat shrinkage stress test)

[Table 1]

The heat shrinkage stress values of the labels of Example 1 were all less than 2.5 MPa as shown in Table 1 and FIG. As a result, in Example 1 of the shrink wrapping body according to the present invention, by suppressing the deformation of the PET bottle covered with the liquid level control shrink label after heat shrinkage, as shown in Table 2, immediately after opening at 22 ° C. Head space of 6m
It was an excellent product with no liquid spill that could be secured for 1 or more.

On the other hand, the heat shrinkage stress value of the label of Comparative Example 1 is 5.3 to 7.3 MPa as shown in Table 1 and FIG.
That is, it was 2.5 MPa or more. As shown in Table 1 and FIG. 4, when the heating peak temperature was 60 ° C. to 75 ° C., the heat shrinkage was not sufficient. As a result, the bottle cannot be completely or almost completely adhered to the outer peripheral surface of the bottle, and the adhesive strength is extremely weak, resulting in an incomplete adhered coating, and the label is easily peeled off, which causes a problem. Met. As a result, as shown in Table 2, in the labeled package of Comparative Example 1, the labeled PET bottle after heat shrinkage is deformed, the liquid level rises, and a liquid spill is likely to occur, which is inferior. It was a thing.

The heat shrinkage stress value of the label of Comparative Example 2 was as shown in Table 1 and FIG. 5 when the heating peak temperature was 60 ° C.
The heat shrinkage was not sufficient. As a result, the bottle is not completely or almost incapable of covering and adhering to the outer peripheral surface of the bottle, and the incomplete covering and adhering state has extremely weak adhesive strength, so that the label easily peels off and there is a problem. Met. In the heating peak temperature range of 70 ° C to 95 ° C,
The heat shrinkage stress value of the label of Comparative Example 2 is 2.6 to 3.9 MPa as shown in Table 1 and FIG. 5, that is, 2.5 MPa.
That was all. As a result, in the labeled package of Comparative Example 2, the deformation of the PET bottle covered with the liquid level control shrink label after heat shrinkage deforms, the liquid level rises, and liquid spillage easily occurs. A bottle,
It was inferior. Further, when the heating peak temperature was 110 ° C., the label did not shrink uniformly and pinholes were generated, which was a problem.

(Experiment 2: Headspace change amount measurement test) Before measuring the headspace change amount from the upper end of the mouth of the labeled packages of Example 1 and Comparative Examples 1 to 2 to the liquid surface, The amount of headspace that does not spill was confirmed as follows. First, a PET bottle of the same size as that used in the following experiment was filled with water until spillage occurred, and the cap was closed. Then, the cap of the bottle was opened, and the amount of water overflowed was measured. As a result, up to 6
There was a spill of ml. Therefore, it was confirmed that the change amount of the head space was 6 ml or more. Therefore, the following criteria were evaluated. (Evaluation Criteria) O indicates that the head-space change amount is 6 ml or more. X indicates that the head-space change amount is less than 6 ml.

Using the shrink packages of Example 1 and Comparative Examples 1 and 2 to which the labels were attached at the respective heating temperatures obtained above, the shrink labels were heated to a peak temperature of 95 ° C.
Was treated for 20 seconds, and 100 seconds later, the amount of change in the headspace of the shrink package, which had dropped to 22 ° C, and the headspace when the cap was opened was measured and evaluated based on the results. The results are shown in Table 2.

(Results of Head Space Change Measurement Test)

[Table 2]

As to the results of the headspace capacity measurement test, as shown in Table 2, the headspace change amount of the shrink label packages of Comparative Examples 1 and 2 {(headspace before cap opening)-(after cap opening). Headspace)} is 4.6 ml and 4.9 ml, respectively, and 6
It was less than or equal to ml, which was a level at which liquid spillage was likely to occur. This means that, in the case of the packaging bodies in which the shrink labels of Comparative Examples 1 and 2 were attached to the bottle, the heat shrinkage stress at the time of shrinking at the heat shrinkage peak temperature is
The heat shrinkage stress of the shrink label is increased in the state of being cooled to 0. This indicates that the PET bottle is tightened from the time when it shrinks, so that the liquid level of the bottle is rising. On the other hand, in the case of the shrink label according to the present invention of Example 1, the head space capacity at the time of label mounting is 9.1 ml, and 6
More than ml was secured, which was a level at which liquid spill did not easily occur. This means that in the case of the packaging body in which the shrink label according to the present invention of Example 1 is adhered to a bottle, the tightening of the label by the label cooled to 22 ° C. 100 seconds later is relaxed from immediately after heating the label, It shows that the shrink packaging body prevents deformation of the bottle, suppresses the rise of the liquid level, and secures a sufficient head space change amount.

Further, using the shrink packages of Example 1 and Comparative Examples 1 and 2 to which the shrink labels obtained above were attached, heat treatment was carried out at a heating peak temperature of 95 ° C. for 20 seconds, and 100 seconds later, 22 ° C. The headspace of the package in Example 2 and the amount of change in the headspace when the label was peeled off were compared and measured. The results are shown in Table 2.

In the case of the shrink labels of Comparative Examples 1 and 2, the head space change amount {(head space in label mounted state)-(head space in label peeled state)} was increased by about 3 ml in each case. It was
This indicates that the PET bottle is tightened and the liquid level rises with the label attached. On the other hand, in the case of the label according to the present invention of Example 1, the amount of change in headspace increased by only about 1.6 ml. This is compared with Comparative Examples 1-2.
In the case of the shrink wrapping body of Example 1, it is shown that tightening of the bottle by the label is alleviated and the rise of the liquid level is suppressed.

[0046]

As described above, according to the label of the present invention, the heat-shrinkable resin film material has a heat-shrinkage stress of 2.5 MPa in a state of being cooled to room temperature after heat-shrinking. As a result, it is possible to provide a label in which the tightening force of the label on the bottle can be suppressed, the rise of the liquid level can be suppressed, and the head space can be secured at a level where liquid leakage does not occur. Therefore, aseptic filling P
Unlike ET bottles, the inside of the container does not become depressurized, so the liquid level of the contents does not drop when opening, and even if you attach a label to a bottle that easily spills, there is a label that does not spill when opening A package can be provided. Further, by shrinking the label according to the present invention on the bottle, restrictions on the shape of the bottle are reduced, so that it is possible to provide a labeled package in which the label is shrunk on the bottle having a variety of shapes. Furthermore, instead of sticking a shrink label only to the body of the bottle, it is possible to full shrink from the bottom to the mouth, so a label-wrapped package that can add a barrier function such as light blocking property. It is something that can provide the body.

[Brief description of drawings]

FIG. 1 is a front view of a labeled package according to the present invention.

FIG. 2 is a graph showing the relationship between the heat shrinkage stress at the vertical axis and the heat shrinkage stress at a heating temperature of 95 ° C. for 20 seconds when the horizontal axis indicates time.

FIG. 3 is a graph showing the relationship between heat shrinkage stress and time in Example 1 at a heating time of 20 seconds and a heating temperature of 60 to 135 ° C.

FIG. 4 is a graph showing a relationship between heat shrinkage stress and time of Comparative Example 1 at a heating time of 20 seconds and a heating temperature of 60 to 135 ° C.

FIG. 5 is a graph showing the relationship between heat shrinkage stress and time in Comparative Example 1 at a heating time of 20 seconds and a heating temperature of 60 to 135 ° C.

[Explanation of symbols]

1 label 2 PET bottle for aseptic filling 3 mouth 4 shoulders 5 torso 6 bottom 7 perforations 8 Labeled packaging

Continued front page    F-term (reference) 3E062 AA09 AB02 AC02 JA04 JA08                       JB05 JC02                 3E067 AA03 AB26 BA03B BA21C                       BB14B BB14C CA01 ED03                       EE04 FA04 FB01                 4F210 AA03 AA12 AE01 AG01 AH54                       AR01 AR12 RA01 RC02 RG05

Claims (4)

[Claims] 1. A shrink label which is attached to the outer peripheral surface of a body of a bottomed cylindrical container, shrinks by heating and tightens, and the shrinking stress of the shrink label cooled after heating shrinks,
A label characterized by being less than 2.5 MPa. 2. The heat shrinkage stress of a shrink label subjected to heat shrinkage at a heating temperature peak value of 45 to 150 ° C. and a treatment time at the heating temperature peak value of 0.5 msec to 30 seconds is 2.5.
The label according to claim 1, which is less than MPa. 3. The label according to claim 1, wherein the base material of the shrink label contains one of a polyolefin resin and a cyclic olefin resin. 4. A labeled packaging body, wherein the label according to any one of claims 1 to 3 is mounted on a synthetic resin bottle and aseptically filled.