JP2004142785A - Shrinking and heat insulating film for wrapping container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a curl phenomenon upon wrapping a container with a shrinking and heat insulating film. <P>SOLUTION: A lateral-uniaxial-type thermoplastic shrink film sheet 1 has a shrink property that the film sheet 1 shows a lateral shrinkage factor of 60% or more and a vertical shrinkage factor of 4% or less under the temperature condition corresponding to a thermal shrinkage condition in a shrinkage tunnel using steam, which is given by immersing the film sheet 1 in hot water of 95°C for 10 minutes. A nonwoven fabric 2 is placed on one surface of the film 1, while the main flow direction of the fibers 2a of the nonwoven fabric 2 is set along the longitudinal direction of the film 1a, and the nonwoven fabric 2 is glued to the surface with an adhesive 4 to form the shrinking heat insulating film F for wrapping the container. The film F is made into a tubular shape, arranged around the outer periphery of the container 3 to be wrapped, and then passed through the shrinkage tunnel using steam, where the thermoplastic shrink film sheet 1 shrinks laterally at a high shrinkage factor. At this time, the film sheet 1 is prevented from extensively shrinking longitudinally on the outside of the nonwoven fabric 2 that does not shrink by heat in the flow direction of the fibers 2a. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heat-insulating shrinkable film for container packaging, which is used for covering and packaging containers such as plastic bottles, bottles, and cans used as containers for soft drinks, taste drinks, foods, seasonings, and the like. It is.
[0002]
[Prior art]
Soft drinks, favorite drinks, foods, seasonings, etc. are sold in plastic bottles such as PET bottles, bottles, cans, or paper containers. Of these containers, plastic bottles, bottles, cans, etc. In recent years, when it is necessary to attach a label to a container, it has been increasingly coated and packaged with a label using a horizontal uniaxial shrink film made of expanded polystyrene (OPS) or polyester (PET).
[0003]
The above-mentioned shrinkable film for container packaging made of OPS or PET is usually a transparent thermoplastic uniaxial heat shrinkable film of about 45 to 60 μm. Then, one end in the width direction of the slit shrinkable film is overlapped with the required size on the other end in the width direction, and the center is sealed with a solvent, an adhesive, an ultrasonic wave, or the like to form a tube. The tubular shrink film cut into a bag and cut to a required length is placed, for example, over the plastic bottle or bottle to be labeled, and placed around the outer periphery of the body, and then passed through a shrink tunnel in this state. By heating under the required shrinkage processing conditions, the shrinkable film is shrunk in the horizontal direction, and is brought into close contact with the outer periphery of the body of a plastic bottle or bottle, thereby applying the printing. Some shrink film, it is constituted such that it is mounted on the plastic bottle or bottle as a label.
[0004]
When a can is used as a container, printing is sometimes performed directly on the can. On the other hand, printing is performed on a PET shrink film, and then the label is attached to the can.
[0005]
By the way, various beverages and foodstuffs packed in containers such as plastic bottles, bottles and cans are sometimes sold in a state of being heated using a hot warmer or the like. In this case, OPS having a thickness of about 45 to 60 μm is used. Since the shrinkable film made of PET or PET lacks heat insulation performance, when a beverage or the like packed in a container equipped with the above-described shrinkable film label is heated to 55 to 60 ° C., the heat of the contents is reduced to the container wall and Since the heat is directly transmitted to the outside through the label, there is a problem in that the container cannot be held in the hand due to its heat. For this reason, a heat-shrinkable shrink film has been proposed.
[0006]
As the uniaxially shrinkable film for containers and packaging having such heat insulation performance, a film made of foamed PP, or a film obtained by laminating shrinkable PET with shrinkable foamed PP having a skin layer has been proposed (for example, Patent Document 1). 1).
[0007]
However, the horizontal uniaxially shrinkable film made of foamed PP or the shrinkable foamed PP with skin layer has a significantly reduced shrinkage performance as compared with the shrinkable film made of OPS or PET. After the bag is formed into a tube having dimensions, it is cut into required dimensions, covered with a container, and arranged on the outer periphery of the body. In this state, the horizontal uniaxial foam PP is passed through a shrink tunnel to the body of the container. If the shrink film is to be brought into close contact, the processing conditions in the shrink tunnel must be changed drastically.Therefore, the shrink tunnel conventionally provided for filling equipment such as plastic bottles and cans is replaced with a new shrink tunnel with different heat shrink conditions. There is a problem that it is necessary to change to equipment, and enormous funds are required for equipment investment. In particular, when a plastic bottle is used as a container to be mounted, if the shrinkage treatment temperature is increased to increase the degree of shrinkage of the foamed PP uniaxially shrinkable film, the plastic bottle itself may be deformed before the label shrinks. There is also a problem.
[0008]
Therefore, a high shrinkage label is desired in order to reduce costs. Further, there is a need for a label suitable for a labeling machine used to label an existing uniaxially contracted OPS or PET film in a predetermined container.
[0009]
In order to provide a label that meets such demands, the present applicant has already proposed a method for manufacturing a horizontal uniaxial high-shrink film. As shown in FIG. 3 (a), the film obtained by this method is obtained by forming a nonwoven fabric 2 on a horizontal uniaxial thermoplastic shrinkable film sheet 1 having high shrinkage performance, and the main flow direction of the fibers 2a of the nonwoven fabric 2 is changed. This is a shrinkable film A for container packaging that is superimposed so as to be in a direction (hereinafter, indicated by an arrow Y in the figure) orthogonal to a main shrinkage direction of the film sheet 1 (hereinafter, indicated by an arrow X in the figure).
[0010]
[Patent Document 1]
Japanese Patent No. 2893286
[0011]
[Problems to be solved by the invention]
However, according to the shrinkable film A for containers and packaging obtained by the manufacturing method proposed by the present applicant, the shrinkage performance in the transverse uniaxial direction can be enhanced, which is extremely useful. For example, a film formed by laminating a nonwoven fabric 2 on a thermoplastic shrinkable film sheet 1 such that the main flow direction of the fibers 2a of the nonwoven fabric 2 is orthogonal to the main shrinkage direction of the film sheet 1 is described. As a result of further devising and studying, generally, when a heat quantity that sufficiently shrinks in the main shrinkage direction is given to the horizontal uniaxial thermoplastic shrinkable film sheet 1 having high shrinkage, the direction orthogonal to the main shrinkage direction is obtained. The non-woven fabric 2 also contracts in the main flow direction of the fibers 2a following the thermal contraction of the thermoplastic shrink film sheet 1 in the same manner. When this is thermally shrunk on the outer periphery of the container 3 to be packaged as a label, the thermoplastic uniaxially shrinkable film sheet 1 which shrinks vertically on the outer surface of the label and the inner surface of the label It has been found that there is a difference in shrink physical properties between the non-woven fabric 2 which cannot be shrunk in the vertical direction.
[0012]
Due to the difference in shrinkage physical properties, for example, after forming the bag into a tube shape with the non-woven fabric 2 inside, it is placed on the outer periphery of the body portion over the container 3 to be packaged, and then passed through a shrink tunnel in this state. When shrinking is performed by heating under the heat shrinkage treatment conditions, as shown in FIG. 3B, the upper and lower ends of the label are rolled up from the surface of the container 3 to be packaged. It was found to cause the phenomenon. In particular, when the generated top curl 4 is located on the shoulder of the container 3 to be packaged, there is a concern that moisture may accumulate in the top curl 4 and a hygienic problem may occur. For this reason, further improvement for eliminating the occurrence of the curl phenomenon is desired.
[0013]
Therefore, as a method for preventing the occurrence of the top curl 4 and the bottom curl 5 as described above, it is conceivable to weaken the shrinkage condition and make the shrinkage state of the thermoplastic shrinkable film sheet 1 incomplete. In the case where the container 3 to be packaged is provided with a screw-type lid 3a, when the lid 3a is turned to open, the label and the container 3 slip and the lid 3a does not open or the lid 3a does not open. May be difficult to open. To this end, we considered applying an adhesive such as hot melt to the inside of the nonwoven fabric 2 of the label, but in this case, the adhesive is absorbed by the nonwoven fabric 2 when the applied amount of the adhesive is small. On the other hand, if the amount of the adhesive applied is greatly increased in order to prevent this absorption, the adhesive such as the above-mentioned hot melt applied on the inner side causes blocking when the bag is formed into a tube shape, and a mouth ( It was found that it was not preferable because the opening of the end portion) became difficult to open, and the label and the container to be packaged 3 slipped, resulting in a problem of lack of processability.
[0014]
Therefore, the inventors of the present invention have conducted various researches and studies to prevent the occurrence of curl phenomenon due to heat treatment at the time of label mounting, having high shrinkage properties, and as a result, the thermoplastic shrinkable film sheet used as a material has been obtained. When the shrinkage in the direction orthogonal to the main shrinkage direction under the predetermined heat shrinkage condition applied at the time of label mounting is 4% or less, the difference in shrinkage physical properties between the non-shrinkable nonwoven fabric and the non-woven fabric in the main flow direction is suppressed. Thus, the present invention was found to prevent the occurrence of the curl phenomenon.
[0015]
Therefore, an object of the present invention is to provide a container for packaging that has high shrinkage and can be mounted on a container without causing a curl phenomenon even during heat treatment for mounting on a container to be packaged. It is intended to provide a shrinkable heat insulating film.
[0016]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a heat shrinkable material having a shrinkage rate of 4% or less in a direction orthogonal to the main shrinkage direction under a predetermined heat shrinkage treatment condition applied when the heat shrinkage is attached to a container. On one side of the plastic uniaxially shrinkable film sheet, a nonwoven fabric is laminated and integrated such that the main flow direction of the fibers of the nonwoven fabric is orthogonal to the main shrinkage direction of the thermoplastic uniaxially shrinkable film sheet.
[0017]
After sealing both ends in the main shrink direction of the thermoplastic uniaxially shrinkable film sheet with the nonwoven fabric inside, and forming a bag in a tubular shape, the tubular material is arranged on the outer periphery of the container to be packed. Given the predetermined heat shrink treatment conditions for mounting to the, regarding the main shrink direction of the thermoplastic uniaxial shrink film sheet, the thermoplastic uniaxial shrink film sheet is shrunk at a high shrinkage rate, Since the fibers are made to follow by narrowing the interval between the fibers in a direction orthogonal to the main flow direction of the fibers, the thermoplastic shrinkable film sheet is shrunk based on the shrinkage properties thereof and is brought into close contact with the outer periphery of the container. At this time, regarding the direction orthogonal to the main shrinkage direction of the thermoplastic shrinkable film sheet, since the shrinkage ratio of the thermoplastic shrinkable film sheet is limited to 4% or less, the non-woven fabric does not shrink in the main flow direction of the fiber. The thermoplastic shrinkable film sheet is not significantly shrunk on the outer peripheral side, so that the occurrence of a top curl or a bottom curl phenomenon is prevented.
[0018]
In addition, the thermoplastic uniaxially shrinkable film sheet has a shrinkage property such that the shrinkage in the main shrinkage direction is 60% or more under predetermined heat shrinkage treatment conditions applied when the film is attached to a container. Thereby, the shrinkage rate of the thermoplastic shrinkable film sheet in the main shrinkage direction can be increased, and the adhesion to the container to be packaged can be increased.
[0019]
Furthermore, by setting the predetermined heat shrinkage treatment condition to a condition of immersing in hot water of 95 ° C. for 10 seconds, the heat shrinkage treatment is performed in a shrink tunnel using steam at the time of mounting on a container to be packaged. Shrinking properties suitable for the case can be provided.
[0020]
Further, an adhesive is applied to one surface of the thermoplastic uniaxially shrinkable film sheet, and after laminating a nonwoven fabric when the adhesive is in a wet state, the adhesive is dried to form the thermoplastic uniaxially shrinkable film sheet and the nonwoven fabric. By laminating and integrating them, a shrinkable heat insulating film for container packaging can be easily manufactured.
[0021]
Furthermore, by making the thermoplastic uniaxially shrinkable film sheet made of polyester, polystyrene, or polyolefin, a thermoplastic uniaxially shrinkable film sheet having a high shrinkage in the main shrinkage direction can be easily used.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0023]
FIGS. 1 (a) (b) and 2 (a) (b) show an embodiment of the shrinkable heat insulating film for container packaging of the present invention, and a predetermined heat treatment to be applied when the film is mounted on a container to be packaged. Under the conditions, for example, when a heat treatment of immersing in hot water of 95 ° C. for 10 seconds corresponding to the heat treatment condition in the shrink tunnel using steam is applied, the shrinkage in the lateral direction (arrow X direction in the figure) is 60% or more. And a shrinkage factor of 4% or less in the vertical direction (arrow Y direction in the figure), preferably 65% or more in the horizontal direction and 3.0% or less in the vertical direction. The horizontal uniaxial type thermoplastic shrinkable film sheet 1a is set in a state where printing is not performed, or in a state where a required pattern is printed in advance by a printing machine such as a gravure printing machine if necessary, and the thermoplastic shrinkage is performed. One side of film sheet 1a On the printing surface) when the printing are performed, the adhesive 6 and a thickness in the wet state, for example, 5 to 10 g / m in dry terms so as to be more thick from about 5μm ² About 30 g / m when the adhesive 6 is in a wet state. ² Is arranged such that the main flow direction of the fibers 2a of the nonwoven fabric 2 is perpendicular to the main shrinkage direction of the thermoplastic shrinkable film sheet 1a, that is, along the direction of arrow Y in FIG. To laminate on the adhesive coated surface. Here, the adhesive 6 in the wet state refers to a state in which the fibers 2a of the nonwoven fabric 2 are applied to the surface of the adhesive 6 when the nonwoven fabric 2 is pressed with a required pressure so that the nonwoven fabric 2 is bonded to the surface to which the adhesive 6 is applied. It refers to the adhesive 6 in a state having a property of being able to enter and be buried. Therefore, as long as the fibers 2a of the nonwoven fabric 2 can be buried by pressing the fibers 2a at the required pressure, the adhesive 6 may be somewhat dry. Thereafter, the adhesive 6 is completely dried in a drying zone or natural drying, and the thermoplastic shrinkable film sheet 1a and the nonwoven fabric 2 are integrated via the adhesive 6, as shown in FIG. It is referred to as shrinkable heat insulating film F for containers and packaging.
[0024]
As a material of the thermoplastic shrinkable film sheet 1a, oriented polystyrene (OPS), polyester (PET) generally used for a transverse uniaxial type thermoplastic shrinkable film as long as the longitudinal shrinkage ratio has the above shrinkage physical properties. , Polyethylene (PE), polypropylene (PP), vinyl chloride (PVC), cyclic olefins, etc. can be used. However, in view of obtaining high shrinkage performance as a transverse shrinkage, PET or OPS is preferred. Is preferred. The thickness may be about 20 to 60 μm. Further, a lubricant, an antistatic agent, a UV absorber and the like may be appropriately blended into the thermoplastic shrinkable film sheet 1a according to the purpose of use.
[0025]
The material of the nonwoven fabric 2 is preferably made of general-purpose plastic such as polypropylene (PP), polyethylene (PE), or polyester (PET) from the viewpoint of price and the like.
[0026]
The adhesive 6 needs to be selected according to the material of the thermoplastic shrink film sheet 1a. That is, for example, when the thermoplastic shrinkable film sheet 1a is made of PET, an organic solvent-based adhesive used for laminating general films, for example, a polyurethane-based adhesive, as a specific example, What is necessary is just to use the thing of the composition which added the polyisocyanate to polyester polyurethane polyol, etc., but when the said thermoplastic shrink film film 1a is made of OPS, aqueous urethane type adhesive 6 and acrylic resin adhesive An adhesive 6 soluble in a solvent mainly composed of alcohol, such as polyether or polyurethane, is selected.
[0027]
When the above-mentioned shrinkable thermal insulation film F for container packaging is mounted on the container 3 to be packaged, the above-mentioned shrinkable thermal insulation film F for container packaging is adjusted to the printing when the thermoplastic shrinkable film sheet 1a is printed. At the required position, if nothing is printed, after slitting to the required width corresponding to the outer peripheral dimension of the part to be packaged of the container 3 to be packaged, the nonwoven fabric 2 surface is turned up. As shown in FIG. 2A, the nonwoven fabric 2 is bent inward by a bag making machine (not shown), and the main shrinkage direction of the thermoplastic shrinkable film sheet 1a in the shrinkable heat insulating film F for container packaging is used. Both edges in the width direction (arrow X direction in the figure) are overlapped in the inward and outward directions over a required size, and the thermoplastic shrinkable film sheet 1a surface at one edge disposed inside and the other end disposed outside. Edge non-woven The two surfaces are centered with the adhesive 6 in the same manner as in the case of bonding the thermoplastic film sheet 1a and the nonwoven fabric 2 in the case of manufacturing the above-mentioned shrinkable heat insulating film F for container packaging shown in FIGS. After sealing, a bag is formed into a tube shape in which the outer surface is the thermoplastic shrink film sheet 1a and the inner surface is the nonwoven fabric 2. Next, after cutting the tube-shaped shrinkable heat insulating film F for container packaging into a prescribed size, as shown in FIG. 2 (b), it is placed over the container 3 to be packaged and arranged on the outer periphery thereof. By applying a predetermined heat shrink condition by passing through the shrink tunnel, the thermoplastic shrink film sheet 1a disposed on the outer surface of the tubular shrink insulating film F for container packaging is thermally shrunk. As shown in (c), the package 3 is attached in close contact with the outer periphery of the container 3 to be packaged.
[0028]
When a predetermined heat shrink condition is applied to the outer periphery of the container 3 to be shrunk, the thermoplastic shrinkable film sheet 1a is moved in a direction orthogonal to the main shrink direction (arrow X direction in the figure). The thermoplastic shrinkable film sheet 1a is wrapped on the outer peripheral side of the nonwoven fabric 2 which hardly shrinks in the main flow direction of the fibers 2a since the shrinkage ratio in the direction of arrow Y) is 4% or less. The shrinkage in the vertical direction of the target container 3 is prevented, so that the conventional thermoplastic shrinkable film sheet 1 shrinks greatly on the outer peripheral side of the non-woven fabric 2 that does not shrink, and thus the top curl or the like occurs. The occurrence of the bottom curl phenomenon is prevented.
[0029]
As described above, according to the shrinkable heat insulating film F for container packaging of the present invention, the packaging target container 3 can be wrapped with the nonwoven fabric 2 inside and the thermoplastic shrinkable film sheet 1a arranged on the outer surface. It is possible to perform packaging with heat insulation performance based on the presence of voids between the fibers 2a of the nonwoven fabric 2, and even if the beverage or the like packed in the container 3 to be packaged is heated to 55 to 60 ° C. Can be suppressed from being directly transmitted to the outside through the container wall and the packaging, so that the packaging target container 3 can be held in hand. Further, since the thermoplastic film sheet 1a can be printed, a container label having heat insulation can be easily manufactured.
[0030]
Furthermore, even if a predetermined heat shrink condition for shrinking the thermoplastic shrink film sheet 1a is given, the occurrence of the curl phenomenon can be prevented, so that the possibility of appearance failure can be prevented.
[0031]
Furthermore, the transverse uniaxial thermoplastic shrinkable film sheet 1a has a shrinkage rate in the transverse direction, which is the main shrinkage direction, of 60% or more under the predetermined heat shrinkage treatment conditions. Based on the shrinkage properties of the thermoplastic shrinkable film sheet 1a, when the shrinkable heat insulating film F for container packaging of the present invention is shrunk, the shrinkable heat insulating film F can be brought into close contact with the outer periphery of the container 3 to be packed. Even when the container 3 is provided with the screw-type lid 3a, the container 3 to be packaged can be securely held through the packaging, so that the screw-type lid 3a can be removed without rotating the container 3 to be packaged. Can be easily opened.
[0032]
Furthermore, since the occurrence of the curl phenomenon in the heat shrinkage treatment can be prevented, the heat shrinkage condition can be strengthened. If the heat shrinkage condition is strengthened in this way, the packaging can be more closely adhered to the container 3 to be packed. Also, by strengthening the heat shrinking condition as described above, the package can be sufficiently shrunk even on a site requiring a large shrinkage, such as the shoulder portion of the container 3 to be packed, so that the package can be in close contact. Will be possible.
[0033]
The shrinkable heat insulating film F for containers and packaging of the present invention is obtained by applying an adhesive 6 to one surface of a thermoplastic uniaxial shrinkable film sheet 1a, laminating the nonwoven fabric 2 when the adhesive 6 is in a wet state, and then bonding the adhesive. Since the agent 6 is manufactured by drying, it can be easily manufactured.
[0034]
It should be noted that the present invention is not limited to only the above embodiment, and that the shrinkable heat insulating film F for container packaging may be used not only as a label but also as a container packaging requiring heat insulation, The container 3 can be used for packaging containers other than plastic bottles, bottles, and cans as long as it is desired to prevent the heat of the contents from being transmitted to the outside. Insulation of the cold heat of the contents and that it can also be used for packaging when prevention of heat transfer from the outside to the contents of the container is required, in the above, in order to respond to the heat shrinkage conditions by the shrinkage tunnel using steam Although the contraction physical properties of the thermoplastic uniaxially shrinkable film sheet 1a are specified under the condition of immersion in hot water of 95 ° C. for 10 seconds, the mounting to the container 3 to be packaged is performed by using an oil bath or hot air. If the heat shrinkage conditions used at the time of mounting the container are different, for example, the shrinkage properties in the direction orthogonal to the main shrinkage direction of the thermoplastic uniaxially shrinkable film sheet 1a under the heat shrinkage treatment conditions actually used, It is needless to say that the contraction property in the contraction direction may be defined, and it is needless to say that various changes can be made without departing from the scope of the present invention.
[0035]
【Example】
(1)
The thermoplastic shrinkable film sheet 1a is made of PET and has a shrinkage property of 100.0% in the horizontal direction (main shrinkage direction) when immersed in hot water of 95 ° C. for 10 seconds, and the shrinkage ratio in the vertical direction (main shrinkage direction) is 80.0%. A shrinkage ratio of 0.0% (in the direction orthogonal to the shrinkage direction) is prepared, and the thermoplastic shrinkable film sheet 1a is back-printed in advance with a required pattern using a urethane ink on a printing machine. After applying the adhesive 6 on the printing surface of the thermoplastic shrink film sheet 1, the coated surface of the adhesive 6 in a wet state is applied with a basis weight of 20 g / m 2. ² After laminating the PP nonwoven fabric 2, the shrinkable heat insulating film F for container packaging was manufactured by drying.
The shrinkable heat insulating film F for container packaging was formed into a tube by a bag making machine so that the nonwoven fabric 2 was bent inward, and then cut into a prescribed size, and the beverage to be the container 3 to be packaged was filled. When placed on the outer periphery of the body of the bottle can and passed through a shrink tunnel using steam, it can be neatly shrunk and adhered along the outer shape of the container, and the appearance of top curls etc. It could be attached as a label without defect.
The container 3 to which the label was attached by the shrinkable heat insulating film F for container packaging could be smoothly opened by twisting the lid of the can in a state where the label portion was held in hand.
(2)
The thermoplastic shrinkable film sheet 1a made of PET has a shrinkage property of 74.0% in the transverse direction (main shrinkage direction) when immersed in hot water of 95 ° C. for 10 seconds and the longitudinal direction (main shrinkage). The shrinkage heat insulating film F for container packaging was manufactured in the same manner as in Example (1), except that the shrinkage in the direction perpendicular to the direction was 2.0%.
After the shrinkable heat insulating film F for container packaging is formed into a tubular shape, it is cut into a required length, placed on the outer periphery of the packaging target container 3 filled with the beverage, and passed through a shrink tunnel using steam. As a result, there was a tendency for the resin to shrink until it came into close contact with the container and to have a top curl, but the appearance did not become poor.
(3)
The thermoplastic shrinkable film sheet 1a made of PET has a shrinkage property of 72.0% in the horizontal direction (main shrinkage direction) when immersed in warm water of 95 ° C. for 10 seconds and the longitudinal direction (main shrinkage). The shrinkage heat-insulating film F for containers and packaging was manufactured in the same manner as in Example (1), except that the shrinkage rate in the direction perpendicular to the direction was 5.0%.
After the shrinkable heat insulating film F for container packaging is formed into a tubular shape, it is cut into a required length, placed on the outer periphery of the packaging target container 3 filled with the beverage, and passed through a shrink tunnel using steam. Then, top curl occurred. When the shrinkage condition was relaxed to prevent this top curl, the shrinkage condition was loosely wound around the container 3 to be packaged, and the appearance did not deteriorate. When the user twisted the lid while holding the label portion of the packaging target container 3 in his hand, the packaging target container 3 was easily turned within the label and could not be easily opened.
(4)
The thermoplastic shrinkable film sheet 1a made of PET has a shrinkage property of 60.0% in the horizontal direction (main shrinkage direction) when immersed in hot water of 95 ° C. for 10 seconds and the longitudinal direction (main shrinkage). The shrinkage heat insulating film F for container packaging was manufactured in the same manner as in Example (1), except that the shrinkage rate in the direction perpendicular to the direction was 7.0%.
After the shrinkable heat insulating film F for container packaging is formed into a tubular shape, it is cut into a required length, placed on the outer periphery of the packaging target container 3 filled with the beverage, and passed through a shrink tunnel using steam. As a result, a top curl was generated, and the top curl was not settled even when the conditions for the shrinkage treatment were loosened, resulting in poor appearance.
(5)
When the thermoplastic shrinkable film sheet 1a is made of OPS and immersed in warm water of 95 ° C. for 10 seconds, the shrinkage in the horizontal direction (main shrinkage direction) is 68.0% and the vertical direction (perpendicular to the main shrinkage direction). The direction of shrinkage is -5.0%, an alcohol-soluble acrylic ink is used as the printing ink, and an aqueous urethane-based adhesive is used as the adhesive 6, respectively. Similarly, a shrinkable heat insulating film F for container packaging was manufactured.
After the shrinkable heat insulating film F for container packaging is formed into a tubular shape, it is cut into a required length, placed on the outer periphery of the packaging target container 3 filled with the beverage, and passed through a shrink tunnel using steam. As a result, it adhered along the outside of the container 3 to be packed without any problem, and no top curl was observed.
[0036]
【The invention's effect】
As described above, the shrinkable heat insulating film for containers and packaging of the present invention exerts the following excellent effects.
{Circle around (1)} Under a predetermined heat shrinkage treatment condition to be applied at the time of attachment to a container, one side of a thermoplastic uniaxially shrinkable film sheet having a shrinkage property of not more than 4% in a direction orthogonal to the main shrinkage direction, Since the nonwoven fabric is laminated and integrated such that the main flow direction of the fibers of the nonwoven fabric is orthogonal to the main shrinkage direction of the thermoplastic uniaxially shrinkable film sheet, the heat insulating performance based on the voids of the nonwoven fabric Can be performed, and the curl phenomenon can be prevented from occurring even when given heat shrinkage conditions are given, so that the possibility of appearance defects can be prevented. Also, by preventing the occurrence of the curl phenomenon in the heat shrinkage treatment, it is possible to strengthen the heat shrinkage condition, and thus, by strengthening the heat shrinkage condition, the packaging can be more closely adhered to the container to be packed. In addition, by strengthening the heat shrink condition as described above, the package can be sufficiently shrunk and adhered to a region requiring a large shrinkage, such as a shoulder portion of the container to be packed.
{Circle around (2)} The thermoplastic uniaxially shrinkable film sheet has a shrinkage property such that the shrinkage rate in the main shrinkage direction is 60% or more under predetermined heat shrinkage treatment conditions applied when the film is attached to a container. By doing so, it is possible to increase the shrinkage in the main shrinkage direction of the thermoplastic shrinkable film sheet and increase the adhesiveness to the container to be packaged, and therefore, when the container to be packaged has a screw-type lid. Even if there is, since the container to be packaged can be securely held by the packaging portion, the screw-type lid can be easily opened without rotating the container to be packaged.
{Circle around (3)} The heat shrinking process is performed in a shrinking tunnel using steam at the time of mounting on a container to be packaged by adopting a configuration in which the predetermined heat shrinking process condition is a condition of immersing in hot water of 95 ° C. for 10 seconds. In such a case, it is possible to provide suitable physical properties for shrinkage.
{Circle over (4)} An adhesive is applied to one side of the thermoplastic uniaxially shrinkable film sheet, a nonwoven fabric is laminated when the adhesive is in a wet state, and then the adhesive is dried. By laminating and integrating them, a shrinkable heat insulating film for container packaging can be easily manufactured.
(5) By making the thermoplastic uniaxially shrinkable film sheet made of polyester, polystyrene, or polyolefin, a thermoplastic uniaxially shrinkable film sheet having a high shrinkage in the main shrinkage direction can be easily used.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an embodiment of a shrinkable heat insulating film for containers and packaging according to the present invention, in which (a) shows a manufacturing process and (b) shows a manufactured state.
FIGS. 2A and 2B show a procedure for packaging a container to be packaged by using the shrinkable heat insulating film for container packaging of FIG. 1, wherein FIG. It is a schematic diagram which shows the state which arrange | positioned, and (c) each shows the state which passed through the contraction tunnel.
FIG. 3A is a schematic perspective view showing an example of a shrinkable film for container packaging obtained by a conventionally proposed manufacturing method, and FIG. 3B is a film having the same configuration as the film shown in FIG. It is a schematic diagram showing the state where the produced label was attached to the container.
[Explanation of symbols]
F Shrink insulation film for containers and packaging
1,1a thermoplastic shrinkable film sheet (thermoplastic uniaxial shrinkable film sheet)
2 Non-woven fabric
2a fiber
6 adhesive

Claims (5)

Under predetermined heat shrink treatment conditions to be applied at the time of attachment to a container, a nonwoven fabric is formed on one surface of a thermoplastic uniaxially shrinkable film sheet having shrinkage physical properties in which a shrinkage ratio in a direction orthogonal to the main shrinkage direction is 4% or less. A shrinkable heat insulating film for container packaging, characterized in that the nonwoven fabric is laminated and integrated so that the main flow direction of the fibers of the nonwoven fabric is orthogonal to the main shrinkage direction of the thermoplastic uniaxially shrinkable film sheet. 2. The container according to claim 1, wherein the thermoplastic uniaxially shrinkable film sheet has shrinkage properties such that the shrinkage in the main shrinkage direction is 60% or more under predetermined heat shrinkage treatment conditions applied when the film is attached to the container. Shrink insulation film for packaging. The shrinkable heat insulating film for container packaging according to claim 1 or 2, wherein the predetermined heat shrinkage treatment condition is a condition of immersing in hot water of 95 ° C for 10 seconds. An adhesive is applied to one surface of the thermoplastic uniaxially shrinkable film sheet, and after laminating the nonwoven fabric when the adhesive is in a wet state, the adhesive is dried to laminate the thermoplastic uniaxially shrinkable film sheet and the nonwoven fabric. The shrinkable heat insulating film for container packaging according to claim 1, 2 or 3, wherein the heat insulating film is integrated. 5. The shrinkable heat-insulating film for containers and packaging according to claim 1, wherein the thermoplastic uniaxially shrinkable film sheet is made of polyester, polystyrene, or polyolefin.

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