JP2012051644A - Lid material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lid material which includes laminates without including a metal foil layer as a lid member of a cup-shaped container, and can obtain sufficient dead holding property, and unsealability and resealablity.SOLUTION: The lid material includes laminates without including the metal foil layer sealing an opening part of the cup-shaped container body. The laminates are configured so that sheet layer and an inner layer are laminated via a hot melt layer formed by a hot melt type adhesive of viscoelasticity.

Description

  The present invention relates to a lid made of a laminate that does not include a metal foil such as aluminum that can be heat-bonded and sealed to a tray or cup-shaped container for packaging instant noodles such as instant noodles, fried noodles, and pasta. Specifically, the lid can be partially peeled off from the container and opened, and after pouring hot water into instant noodles and the like contained in the container, the lid is removed again and the opening can be resealed and covered Regarding materials.

  Conventionally, for instant food containers such as instant noodles, a lid material is used that is opened about half when pouring hot water, and then resealed after pouring hot water. The lid is composed of a multilayer laminate in which a heat-adhesive resin layer that can be thermally bonded to a container in a peelable manner, an aluminum foil having excellent shape retention, and a paper layer that has been printed on the surface are laminated. .

  When cooking instant noodles contained in a container, first, the lid is peeled off about half and the container is opened. At this time, since the lid material is laminated with aluminum foil, the peeled lid material is held in a half-open state, so that hot water can be poured from the opening. After pouring hot water, when the lid is returned to its original state, the lid does not warp, so that the opening of the container can be covered and resealed. Thus, the cover material of the structure which laminated | stacked aluminum foil has the characteristic (henceforth dead hold property) that the shape which can peel the cover material can be maintained, and can be returned to the original state.

  However, the lid member made of a laminate in which aluminum foil is laminated has a problem that a metal detector for inspecting a metal foreign object that may be erroneously mixed in the container body containing the contents cannot be used, In the incineration treatment of the packaging container after use, there has been a problem that the aluminum foil may become an ingot and adhere to the furnace wall or the like of the incinerator. In order to solve these problems, attempts have been made to use a laminate having a structure that does not include an aluminum foil in the lid. Since the lid material made of a laminate that does not contain an aluminum foil does not have dead hold properties, research to provide the lid material with dead hold properties has been actively conducted, and a paper layer and a sealant on the back surface of the paper layer have been studied. A lid member having a tab on the periphery of a laminated structure provided with a layer, and extending in the direction orthogonal to the tab to the middle of the sealant layer or the back surface of the sealant layer and the paper layer, at least from the tab to at least the substantially central portion of the lid member A lid member provided with a cut line is disclosed (for example, see Patent Document 1).

  In addition, it is made of a laminate that does not contain aluminum foil, and has a peeling tab and an opening tab on the outer peripheral edge, and both tabs are provided at a position approximately 90 ° from the center. Is divided into an easy-peeling region formed in a predetermined region near the width of the base of the peeling tab at the center and an adhesive region other than the easy-peeling region, and is laminated and adhered to each other. A lid for an instant food container has been proposed in which perforations are formed by half-cuts on both sides of an easily peelable region slightly from the boundary line of the adhesive region (see, for example, Patent Document 2).

JP 2001-10657 A JP 2002-37311 A

  However, the lid material described in Patent Document 1 has a structure in which a cut line is applied to the sealant layer or halfway between the sealant layer and the back side of the paper layer to impart dead hold properties, and the moisture resistance and gas barrier properties of the lid material are reduced. However, if the depth of the cut line is shallow, the deterioration of the moisture resistance and gas barrier property of the lid can be reduced, but there is a problem that sufficient dead hold property cannot be obtained. Furthermore, there is a problem that the number of processes for applying the score line increases.

  In addition, since the cover material described in Patent Document 2 has perforations on the surface sheet, the composite sheet maintains moisture resistance and gas barrier properties, so that the moisture resistance and gas barrier properties as in Patent Document 1 are reduced. This is a configuration that has been eliminated. However, there are problems that the number of steps for forming the easy peeling region and the perforation are increased on the surface sheet, and that the easy peeling region and the perforation are required to be registered, so that troublesome quality control is required. Further, when opening the lid of the instant food container, as described in paragraph (0019), “as shown in the perspective view of FIG. 5, first, a peeling knob at the tip of the strip-shaped easy peeling region (L1) Pinch (22a), bend forward with a half-cut groove (48) on the base of the back side, and then peel easily along the perforation (32) using this half-cut groove (48) as a trigger An operation of “peeling from the easily peelable layer (50) in the region (L1) and removing the top sheet (30) in the easily peelable region (L1) together with the peeling knob (22a)” is performed, and then the paragraph (0020) 6) As shown in FIG. 6, while pulling up the opening knob (22b), it peels off from the container flange portion (12) up to the portion where the surface sheet (30) is peeled and removed in the central strip-shaped easy peeling region. That stripping is removed Folding from the composite sheet (40) of the part completes the opening process ", and two actions are required to open the lid, which is troublesome for the user and can be opened with one action. Development of a new lid is desired.

  In view of the conventional problems as described above, the present invention comprises a laminate that does not include a metal foil layer as a lid material for a cup-shaped container body, and provides sufficient dead-hold properties to provide openability and resealability. An object of the present invention is to provide a lid member that can be used.

  In order to solve the above-mentioned problem, the present invention described in claim 1 is a lid member made of a laminate that does not include a metal foil layer that seals the opening of the cup-shaped container body, wherein the laminate has a hot melt layer. A cover material comprising a paper layer and an inner layer laminated, wherein the hot melt layer is formed of a hot melt adhesive having viscoelasticity.

Moreover, the present invention described in claim 2 is the lid material according to claim 1, wherein the hot melt adhesive includes a thermoplastic resin and a tackifier, and the measurement temperature is T. The storage modulus of the hot melt adhesive measured at temperature T is defined as G ′, the loss elastic modulus is G ″, and the vibration absorption coefficient (tan δ) can be expressed by the equation [tan δ = G ″ / G ′]. The vibrational absorption coefficient (tan δ) is 4.0 × 10 ⁻¹ or more in the measurement temperature range of 0 ° C. ≦ T ≦ 50 ° C.

  Moreover, the present invention according to claim 3 is the lid according to claim 1 or 2, wherein the laminate is intermediate between the hot melt layer and the inner layer or the paper layer and the hot melt layer. It is characterized in that layers are laminated.

  Moreover, the present invention described in claim 4 is the lid member according to any one of claims 1 to 3, wherein a hot melt layer non-formation part is provided in which the hot melt layer is removed at an outer peripheral edge of the lid member. It is characterized by being.

  Moreover, the present invention according to claim 5 is the lid member according to claim 4, wherein the hot melt layer non-formation portion is provided with a spot adhesion portion partially formed by the hot melt adhesive. It is characterized by being.

  According to a sixth aspect of the present invention, in the lid according to the fourth or fifth aspect, the side of the paper layer laminated with the hot melt layer, and the hot melt layer of the inner layer or the intermediate layer. A thermoplastic resin layer is laminated on the side to be laminated.

  According to the first aspect of the present invention, the cover material has a laminated structure that does not include a metal foil layer such as aluminum, so that it is possible to inspect for contamination of metal foreign objects by a metal detector and incinerate the cover material after use. Processing is possible. Further, the laminate constituting the cover material is composed of a paper layer and an inner layer laminated via a hot melt layer, and the hot melt layer is formed of a hot melt adhesive having viscoelasticity. As a result, it is possible to give the lid material a good dead hold property, so that when the lid material is peeled off from the cup-shaped container body, the lid material of the peeled portion can be held in a folded state due to the dead hold property. Can be formed. Therefore, there is an effect that it is possible to open with one action and to provide convenience without opening with two actions as in the prior art. Further, when the peeled portion of the lid member is returned to the original state, the opening of the container can be covered, and unsealing and resealability can be obtained by a simple operation. Furthermore, since the step of perforating by half-cutting as in the prior art can be omitted, the process can be simplified.

According to the invention described in claim 2, the hot melt adhesive comprises a configuration containing a thermoplastic resin and a tackifier, the measurement temperature is T, and the hot melt adhesive is measured at the measurement temperature T. When it is defined that the storage elastic modulus of the agent is G ′, the loss elastic modulus is G ″, and the vibration absorption coefficient (tan δ) can be expressed by the equation [tan δ = G ″ / G ′], 0 ° C ≦ T ≦ 50 ° C. In addition to the above effects, a more excellent dead hold property can be obtained by adopting a configuration in which the vibration absorption coefficient (tan δ) is 4.0 × 10 ⁻¹ or more in the measurement temperature range.

  According to the invention of claim 3, the laminate is configured by laminating an intermediate layer between the hot melt layer and the inner layer or the paper layer and the hot melt layer. In addition to the above effects, the lid material can provide excellent moisture resistance and gas barrier properties.

  According to the invention described in claim 4, the cup-shaped container main body has a configuration in which a hot melt layer non-forming portion from which the hot melt layer is removed is provided on the outer peripheral edge of the lid member. When covering the opening with a lid and heat-bonding with a hot plate, the hot-melt adhesive that forms the hot-melt layer melts even if the temperature of the hot plate increases or the pressure increases, and the hot plate is melted. Since it does not adhere, it prevents the next lid from adhering to the hot plate when the next lid is heat-bonded, improving workability and setting range of temperature and pressure and other thermal bonding conditions. There is an effect that can be widened.

  According to the invention described in claim 5, the cover material is formed by providing the spot-bonded portion partially formed by the hot-melt adhesive in the hot-melt layer non-formed portion. Can be prevented from floating between the outer peripheral paper layer and the inner layer or intermediate layer.

  According to the invention of claim 6, the thermoplastic resin layer is formed on the side of the paper layer that is laminated with the hot melt layer and on the side of the inner layer or the intermediate layer that is laminated with the hot melt layer. When the opening of the cup-shaped container body is covered with a lid material and thermally bonded with a hot plate, the portion without the hot melt adhesive that forms the hot melt layer in the thermal bonding region is The thermoplastic resin layer laminated on the paper layer and the thermoplastic resin layer laminated on the inner layer or the intermediate layer are in direct contact with each other, and are thermally bonded and integrated, so that the outer peripheral edge of the lid material and the paper layer It is possible to more reliably prevent floating between the inner layer and the intermediate layer.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st embodiment of the cover material concerning this invention, Comprising: (a) is a top view which shows the state which heat-bonded the cover material concerning this invention to the opening part of a cup-shaped container main body, (b) is It is a front view which shows the state which heat-bonded the cover material concerning this invention to the opening part of the cup-shaped container main body. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the laminated structure of the laminated body of the cover material concerning this invention, Comprising: (A) is sectional drawing which shows 1st embodiment of the cover material concerning this invention, (B) is the cover material concerning this invention. It is sectional drawing which shows the structural example of other laminated bodies. In 1st embodiment of the cover material concerning this invention, it is explanatory drawing which shows the state which opened a part of cover material. It is a figure which shows 2nd embodiment of the cover material which concerns on this invention, Comprising: (a) is the top view which saw through the hot-melt layer of the cover material concerning this invention, (b) is Y which shows the laminated structure of a laminated body FIG. It is a figure which shows 3rd embodiment of the cover material which concerns on this invention, Comprising: (a) is the top view which saw through the hot-melt layer of the cover material concerning this invention, (b) is Z which shows the laminated structure of a laminated body FIG.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of a lid material according to the present invention, in which (a) is a plan view showing a state in which the lid material according to the present invention is thermally bonded to an opening of a cup-shaped container body. (B) is a front view showing a state in which the lid according to the present invention is thermally bonded to the opening of the cup-shaped container body, and FIG. 2 is a diagram for explaining the laminated structure of the laminate of the lid according to the present invention. (A) is a cross-sectional view showing a first embodiment of a lid material according to the present invention, (B) is a cross-sectional view showing a configuration example of a laminate of the lid material according to the present invention, and FIG. 3 is a lid material according to the present invention. FIG. 4 is a diagram showing a second embodiment of the lid according to the present invention, wherein FIG. 4 is a diagram according to the present invention. FIG. 5 is a plan view illustrating the hot melt layer of the lid material, FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows embodiment, (a) is the top view which saw through the hot-melt layer of the cover material concerning this invention, (b) is ZZ sectional drawing which shows the laminated structure of a laminated body, Reference numerals 1, 1 ′, 1 ″ are lid materials, 1 a is an opening piece, 2 is a picking part for opening, 10 is a paper layer, 11 is a hot melt layer, 12 is an intermediate layer, 13 is an inner layer, and 14 is a light shield. 15 is a hot melt layer non-formation part, 16 is a thermoplastic resin layer, 17 is a spot adhesion part, 20 is a cup-shaped container body, 21 is a flange, 22 is a pouring spout, and A is an opening picking part. The outer edge of the cup-shaped container body, B is the center of the cup-shaped container body, and C is the outer edge A of the cup-shaped container body among the intersections intersecting the perpendicular line hanging from the lid material peeled on the line connecting A and B , H is the shape from the tip of the opening knob of the opened lid with a flange Vertical height extending in a horizontal plane which is, l denotes the length connecting the A and C, S is a thermal bonding unit, respectively.

  1st embodiment of the cover material concerning this invention is as showing in FIGS. 1-3. As shown in FIGS. 1 (a) and 1 (b), the first embodiment of the lid 1 according to the present invention has, for example, a flange 21 on the outer periphery of the opening of the cup-shaped container body 20 having a circular opening on the upper surface. And a circular lid 1 that is substantially the same size as or slightly larger than the periphery of the flange 21 of the cup-shaped container body 20 is placed so as to cover the opening of the cup-shaped container body 20, and the lid 1 The flange 21 of the cup-shaped container body 20 is thermally bonded to seal the cup-shaped container body 20. The hatched portion in FIG. 1 (a) indicates a thermal bonding portion S formed by thermally bonding the lid member 1 and the flange 21. The circular lid member 1 includes an opening knob 2 that projects outward from the outer peripheral edge of the cup-shaped container body 20 at the outer peripheral edge. The lid member 1 is composed of a laminated body that does not include a metal foil layer. In addition, the metal foil layer described in the present invention is made of aluminum, iron, tin, or an alloy thereof.

  FIG. 2 is a view for explaining the laminated structure of the laminated body of the lid material according to the present invention, and is a cross-sectional view showing only the lid material taken along line XX of FIG. FIG. 2A is a cross-sectional view showing a laminate of the first embodiment of the lid according to the present invention, and FIG. 2B is a cross-sectional view showing a configuration example of another laminate of the lid according to the present invention. As shown in FIG. 2 (a), the lid 1 of the present invention comprises a laminate having a structure in which a paper layer 10, a hot melt layer 11, an intermediate layer 12, and an inner layer 13 are sequentially laminated from the outside. Although not shown in the drawings, the paper layer 10 is usually printed with a product name, a cooking method, and the like. The intermediate layer 12 is laminated to prevent moisture breakage and gas barrier properties depending on the storage stability of the contents, or to prevent the lid material from tearing when the lid material is opened. It is appropriately provided depending on the adhesive strength between the lid member and the cup-shaped container body. In other words, when the lid material does not require excellent moisture resistance and gas barrier properties, or when strong adhesive strength between the lid material and the cup-shaped container body is not required, the intermediate layer 12 is not provided and the hot melt layer 11 is interposed. Thus, the paper layer 10 and the inner layer 13 can be laminated.

  In the laminate of the lid material 1, the intermediate layer 12 can be laminated between the hot melt layer 11 and the inner layer 13 or between the paper layer 10 and the hot melt layer 11. And the inner layer 13 are preferred because there is no delamination of the lid material 1 during transportation and storage of the product. Although a surface layer can be laminated on the outer surface side of the paper layer 10, there is a possibility that the dead hold property is lowered, and when a surface layer is provided, it is preferable to use a plastic film having a thickness of 20 μm or less.

The lid material 1 of the present invention has a configuration in which a paper layer 10 and an inner layer 13 are laminated on a laminate through a hot melt layer 11, and the hot melt layer 11 is formed of a hot melt adhesive having viscoelasticity. It is important that the lid member 1 is easily plastically deformed by such a configuration, and the lid member 1 can be provided with an excellent dead hold property. Further, the hot melt adhesive forming the hot melt layer 11 is composed of a thermoplastic resin and a tackifier, and the storage temperature of the hot melt adhesive measured at the measurement temperature T is T. When the modulus is defined as G ′, the loss elastic modulus is G ″, and the vibration absorption coefficient (tan δ) can be expressed by the equation [tan δ = G ″ / G ′], in the measurement temperature range of 0 ° C. ≦ T ≦ 50 ° C. The vibration absorption coefficient (tan δ) preferably has a characteristic of 4.0 × 10 ⁻¹ or more.

  FIG. 2 (b) is a cross-sectional view showing a laminated body of another embodiment of the lid material according to the present invention. The paper layer 10, the hot melt layer 11, the light shielding layer 14, the intermediate layer 12, and the inner layer 13 are arranged from the outside. It consists of the laminated body of the structure laminated | stacked one by one. When the lid member 1 needs to have light shielding properties due to the contents contained in the cup-shaped container body 20, the light shielding layer 14 can be laminated on the side of the intermediate layer 12 facing the hot melt layer 11. . The surface on which the light shielding layer 14 is provided may be the side of the paper layer 10 facing the hot melt layer 11. The light shielding layer is a paper layer or an intermediate layer using white ink mainly composed of titanium oxide or the like, black ink mainly composed of carbon black, gray ink mainly composed of aluminum paste, or a mixed ink thereof. Are provided by a printing method or a coating method. Moreover, the shape of the lid | cover material 1 is not limited to circular shape, It is arbitrary and can be made into square shape, an ellipse shape, etc., and is suitably selected by the shape of the opening part of a cup-shaped container main body.

Next, a method of using the package body in which the lid 1 according to the first embodiment is thermally bonded to the opening of the cup-shaped container body 20 will be described with reference to FIGS. 1 and 3.
The opening knob 2 shown in FIG. 1 (b) is picked and pulled with a finger, and the lid 1 is peeled off from the flange 21 of the cup-shaped container body 20 as shown in FIG. To do. Since the hot melt layer 11 is laminated on the laminate of the lid material 1, the lid material 1 is plastically deformed and excellent dead hold property is obtained. Therefore, the lid material 1 can be easily folded and peeled open pieces The state is maintained as it is without returning to the original position, and hot water or the like can be poured into the cup-shaped container body 20 from the pouring port 22 with confidence. When the lid 1 is peeled off, when the opening knob 2 is pulled up and peeling starts from the flange 21 of the cup-shaped container body 20, the opening knob 2 is opposed to the opening knob 2 of the lid 1 Folding to the outer edge side (the angle formed by the lid member 1 peeled off from the flange 21 of the cup-shaped container body 20 is approximately 180 °), and when peeled off, a better dead hold property can be obtained, so a preferable opening Is the method.

  Thereafter, although not shown, when the opened piece 1a of the lid member 1 bent again is returned to the original state, the dead hold property of the lid member 1 results in a flat state as shown in FIG. Good resealability is obtained. As described above, the lid 1 is made of a laminate having a hot melt layer 11 so that even a laminate that does not contain a metal foil layer such as an aluminum foil can be opened well with a single action due to excellent dead hold properties. And a lid material having good resealability.

  After the contents are cooked after the lid is closed, the contents are cooked. After the opening knob 2 is picked with a finger and the lid 1 is peeled off from the flange 21 of the cup-shaped container body 20, the cooked contents are removed. You can eat.

  FIG. 4 is a view showing a second embodiment of the lid according to the present invention, wherein (a) is a plan view seen through the hot melt layer of the lid according to the present invention and corresponds to FIG. 1 (a). FIG. As shown in FIG. 4 (a), the lid member 1 'is provided with a hot melt layer non-forming portion 15 from which the hot melt layer 11 is removed at the outer peripheral edge. The hot melt layer non-forming part 15 is preferably provided so as to extend from the outer peripheral edge of the lid 1 ′ to the inner edge of the thermal bonding part S (see FIG. 1). However, if the thickness is 1 mm or less from the outer peripheral edge, the hot melt adhesive of the hot melt layer 11 may protrude to the end surface of the lid 1 'when the lid 1' is thermally bonded to the container body 20. .

  FIG. 4 (b) shows a laminated structure of the laminate, and is a cross-sectional view taken along line YY of FIG. 4 (a). The paper layer 10, the hot melt layer 11, the intermediate layer 12, and the inner layer 13 are sequentially formed from the outside. The thermoplastic resin layer 16 is laminated on the side of the paper layer 10 that is laminated with the hot melt layer 11, and the thermoplastic resin layer 16 is further laminated on the side of the intermediate layer 12 that is laminated with the hot melt layer 11, In the hot melt layer non-formation part 15, the thermoplastic resin layers 16 are in close contact with each other. Until the lid material is thermally bonded to the cup-shaped container body, the closely contacted thermoplastic resin layers 16 are in an unbonded state, but when thermally bonded, the thermoplastic resin layers 16 are thermally bonded and integrated. It is possible to prevent the outer peripheral edge of the lid 1 ′ from floating between the paper layer 10 and the intermediate layer 12. In the case where the intermediate layer 12 is not laminated, the thermoplastic resin layer 16 is laminated on the side of the inner layer 13 that is laminated with the hot melt layer 11. Further, in FIG. 4, a hot melt layer 11 is provided in a portion of the opening knob 2 so as not to straddle the thermal bonding portion S. By doing so, it is possible to prevent the paper layer and the inner layer of the lid material from floating in the opening knob 2.

  As described above, the lid 1 ′ of the second embodiment is configured such that the hot melt layer non-forming portion 15 is provided on the outer peripheral edge of the lid 1 ′ so that the opening of the cup-shaped container body is covered with the lid. When heat bonding is performed with a hot plate, the hot melt adhesive forming the hot melt layer 11 is prevented from melting and adhering to the hot plate even if the temperature of the hot plate is increased or the pressure is increased. However, the thermoplastic resin layer 16 does not necessarily have to be laminated. However, in the configuration in which the thermoplastic resin layer 16 is laminated, the opening of the cup-shaped container body is covered with a lid material and heated with a hot plate. When bonding, the thermoplastic resin layers 16 and 16 are directly bonded by heat and integrated, so that the outer peripheral edge of the lid material does not float, which is a preferable mode.

FIG. 5 is a diagram showing a third embodiment of the lid according to the present invention, wherein (a) is a plan view seen through the hot melt layer of the lid according to the present invention, and corresponds to FIG. 1 (a). FIG. As shown in FIG. 5 (a), the lid member 1 '' is provided with a hot melt layer non-forming portion 15 from which the hot melt layer 11 is removed at the outer peripheral edge. The hot melt layer non-forming part 15 is preferably provided so as to reach from the outer peripheral edge of the lid member 1 ″ to the inner edge of the thermal bonding part S (see FIG. 1). In addition, when the thickness is 1 mm or less from the outer peripheral edge, there is a possibility that the hot melt adhesive of the hot melt layer 11 may stick out to the end surface of the lid material 1 '' when the lid material 1 '' is thermally bonded to the container body 20. It is not preferable.
Furthermore, the donut-shaped hot melt layer non-formation portion 15 has spot-shaped spot adhesion portions 17 formed of a hot-melt adhesive along the center line of the donut-like hot melt layer non-formation portion 15 at a constant interval. Is provided. Further, the shape of the spot bonding portion 17 is not particularly limited, and can be formed in a circular shape, a square shape, a star shape, or the like. The size, the interval between the spot bonding portions 17 and the density thereof are cup-shaped containers. It is appropriately determined in consideration of the outer diameter of the main body and the distance from the outer peripheral edge of the lid member of the hot melt layer non-forming portion 15.
Moreover, the hot melt layer 11 is provided in the part of the opening knob part 2 so as not to straddle the thermal bonding part S. By doing so, it is possible to prevent the paper layer and the inner layer of the lid material from floating in the opening knob 2.

FIG. 5 (b) shows the laminated structure of the laminate, and is a cross-sectional view taken along the line ZZ of FIG. 5 (a). The difference from the second embodiment is that the hot melt layer non-forming portion 15 has a hot melt type. The spot adhesive part 17 partially formed with the adhesive is provided. Others are the same as those of the second embodiment, and the same reference numerals are given and description thereof is omitted.
The lid material 1 '' of the third embodiment is provided with a spot adhesive part 17 partially formed of a hot-melt adhesive in the hot melt layer non-formation part 15, thereby providing the lid material 1 'of the second embodiment. In addition to the effect of the above, the outer peripheral edge of the lid member 1 ″ can be kept in close contact, and the floating between the paper layer 11 and the intermediate layer 12 on the outer peripheral edge of the lid member 1 ″ can be reliably prevented. it can.
In addition, the point that the thermoplastic resin layer 16 does not necessarily have to be laminated is the same as the lid 1 'of the second embodiment, but the cup-shaped structure is formed by laminating the thermoplastic resin layer 16. When the opening of the container body is covered with a cover material and thermally bonded with a hot plate, the outer peripheral edge of the cover material is lifted because the thermoplastic resin layers 16 and 16 are thermally bonded to and integrated with each other except the spot bonding portion 17. This is a preferable mode.

  Next, the material used for each layer which comprises the cover material 1 of this invention, and a formation method are demonstrated.

As the paper layer 10 constituting the lid 1 of the present invention, single-sided coated paper or double-sided coated paper having a basis weight of 50 to 130 g / m ² excellent in printability is preferable.

The hot melt adhesive used for the hot melt layer 11 has viscoelasticity including a base polymer made of a thermoplastic resin, a tackifier, a viscosity modifier, an antioxidant, a filler, a plasticizer, and the like. It has the characteristic that. In particular, the measurement temperature is T, the storage elastic modulus of the hot melt adhesive measured at the measurement temperature T is G ′, the loss elastic modulus is G ″, and the vibration absorption coefficient (tan δ) is [tan δ = G ″ / G When it is defined that it can be expressed by the formula '], a hot-melt adhesive having a characteristic that the vibration absorption coefficient (tan δ) is 4.0 × 10 ^-1 or more in the measurement temperature range of 0 ° C ≦ T ≦ 50 ° C is preferable . The measurement method is as follows.
[Method for measuring storage elastic modulus and loss elastic modulus]
Measuring device: manufactured by T.A. Instruments; ARES-RDA W / FCO rheometer Measuring conditions: temperature T ° C; frequency 1HZ (sine wave)
Measurement sample: Parallel plate with 8mmφ and 2mm thickness

  Examples of the base polymer of the hot-melt adhesive having the above characteristics include synthetic rubber, acrylic, ethylene-vinyl acetate copolymer, polyethylene, and polypropylene. Examples of tackifiers include rosin and its derivatives, terpene resins, hydrocarbon resins, α-methylstyrene-vinyltoluene copolymers, low-molecular styrene resins, coumarone / indene resins, and compatibility, tackiness, and adhesiveness. Among them, rosin, hydrogenated rosin, disproportionated rosin, polymerized resin, and esterified products thereof are preferable. Examples of the viscosity modifier include paraffin wax, microcrystalline wax, and low molecular weight PE wax. The hot melt layer 11 is formed by forming a hot melt adhesive hot melted on the paper layer 11 or the intermediate layer 12 by a coating method such as gravure coating, phanten coating, roll coating, curtain coating, or extrusion coating. Lamination is performed by laminating with the layer 12 or the inner layer 13. The thickness of the hot melt layer 11 is preferably 5 to 30 μm. If it is less than 5 μm, sufficient dead hold property cannot be obtained for the lid member 1, and if it exceeds 30 μm, depending on the sealing conditions, the hot melt adhesive may be used when the lid member 1 and the cup-shaped container body 20 are thermally bonded. There is a possibility that it will stick out to the end face of this, and the cost will increase.

  The intermediate layer 12 is preferably a plastic film having moisture resistance and gas barrier properties from the viewpoint of enhancing the storage stability of the contents, and having strength from the viewpoint of preventing tearing of the lid material when the lid material is opened. A stretched plastic film is preferably used. Specifically, stretched films such as polyester, polypropylene, and nylon, or films obtained by depositing inorganic materials such as aluminum oxide and silicon oxide on these are used. In addition, any of these can be combined and used. The thickness of the plastic film is about 9 to 40 μm. These plastic films can also be used as a surface layer.

  The inner layer 13 is made of a heat-adhesive resin that is heat-bonded to the cup-shaped container body 20 flange 21 in a peelable manner. Examples of the heat-adhesive resin include polyethylene, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ionomer, polypropylene, and easily peelable heat-adhesive resin (EPR). Used, the inner layer 13 is formed by film or extrusion lamination of these resins. In addition, as a method for imparting easy peelability of EPR, a method of forming a multilayer structure in which a thin layer having a weak adhesive force is provided on the surface, a method of expressing easy peelability by a configuration such as blending a resin having low compatibility, etc. These known ones are appropriately employed.

Further, as the thermoplastic resin used for the thermoplastic resin layer 16 laminated on the side of the paper layer laminated with the hot melt layer and the side of the inner layer or intermediate layer laminated with the hot melt layer, the thermoplastic resin used as the thermoplastic resin layer 16 is hot melt extrusion. Possible resins are preferred, low density polyethylene, medium density polyethylene, high density polyethylene, linear (linear) low density polyethylene, polypropylene, ethylene-α olefin copolymer, ethylene-propylene copolymer, ethylene-vinyl acetate. Resins such as a copolymer, an ionomer resin, an ethylene-acrylic acid copolymer, an ethylene-methyl acrylate copolymer, and an ethylene-methacrylic acid copolymer can be used.
Between the intermediate layer 12 and the inner layer 13, between the paper layer 10 and the intermediate layer 12, and the side of the paper layer laminated with the hot melt layer, and the side of the inner layer or intermediate layer laminated with the hot melt layer The thermoplastic resin layers laminated together are laminated by a known technique such as a dry lamination method or an extrusion lamination method to form a laminated material. For example, the following structures are mentioned as a specific laminated structural example of a cover body.
(1) Paper / HM (hot melt) / PET (biaxially stretched polyethylene terephthalate film) / DL (dry lamination adhesive) / EPR
(2) PET / DL / paper / HM / PET / DL / EPR
(3) Paper / PE (polyethylene) / HM (hot melt) / PE / PET / DL / EPR
(4) PET / DL / paper / PE / HM / PE / PET / DL / EPR

  Next, the present invention will be described in more detail with reference to examples.

A predetermined pattern was formed by gravure printing on a coated surface of single-side coated paper 79.4 g / m ² using urethane gravure ink.

Next, PET 12μm (VMPET) with aluminum oxide deposited (VM) on one side as an intermediate layer is used, and a hot-melt adhesive that forms a hot-melt layer is a pressure-sensitive adhesive containing a synthetic rubber base polymer and a tackifier (stock) Using a product name PB-70 manufactured by MORESCO, a hot melt adhesive having a thickness of 10 μm is formed by coating a hot melt adhesive on the VM surface of VMPET, and a non-coated surface of one-side coated paper And an intermediate laminate was produced. The hot melt adhesive forming the hot melt layer had viscoelasticity in the temperature range of 0 ° C to 50 ° C. Further, the vibration absorption coefficient tan δ of the hot-melt adhesive measured by the measurement method described above was 1.0 at 30 ° C.
Next, an easy peel (EP) film (manufactured by J Film Co., Ltd., grade name SMX-Y03) having a single-side corona treatment of 30 μm in thickness is used as the inner layer 13, and a polyester-isocyanate system is used on the PET surface of VMPET of the intermediate laminate Applying adhesive and laminating easy peelable film with single side corona treatment by dry lamination method (DL) and laminating with <pattern printing / single side coated paper / hot melt layer / VMPET / DL / EP film> The body was made.

  Thereafter, winding of the laminate was cut and punched to produce a lid material 1.

The same lid material as in Example 1 was prepared except that a hot-melt adhesive having a vibration absorption coefficient tan δ of 5.5 × 10 ⁻¹ at 30 ° C. was used for the hot melt layer of Example 1.

  The same lid material as in Example 1 was produced except that the thickness of the hot melt layer in Example 1 was set to 20 μm.

  The same lid material as in Example 1 was prepared except that a 40 μm thick single-sided corona-treated film (manufactured by J Film Co., Ltd., grade name SMX-Y03) was used for the EP film of Example 1.

  The same lid material as in Example 2 was prepared except that a 40 μm thick single-side corona-treated film (manufactured by J Film Co., Ltd., grade name SMX-Y03) was used for the EP film of Example 2.

A non-patterned surface of 79.4 g / m ² of single-sided coated paper on which the pattern of Example 1 was formed was subjected to corona discharge treatment, and low-density polyethylene (PE) was hot melt extruded at a thickness of 15 μm and subjected to extrusion lamination. A laminate A was produced by laminating. Next, an isocyanate anchor coating agent (AC) was applied to the VM surface of VMPET of the intermediate layer used in Example 1, PE was hot melt extruded at a thickness of 15 μm on the coated surface, and an extrusion laminating method was used. The laminated body B was produced by laminating.

Next, using the same hot-melt adhesive as in Example 1 on the PE surface of the laminate A, a hot-melt adhesive that is heat-melted is coated to form a hot-melt layer having a thickness of 10 μm. An intermediate laminate was prepared by laminating with the PE surface.
Next, the EP film of Example 1 was used as the inner layer, and the PET surface of the VMPET of the intermediate laminate and the EP film were bonded together by the dry lamination method (DL) in the same manner as in Example 1. <Picture printing / single-sided coated paper / PE / hot melt layer / PE / AC / VMPET / DL / EP film> was produced.
In addition, when the hot melt layer is used as a cover material, a hot melt adhesive is used in synchronism with the pattern on one side coated paper in order to provide a hot melt layer non-formed part where the hot melt layer is removed on the outer periphery. Pattern coated. The hot melt layer non-formed part was provided in a donut shape in a region of a distance of 8 mm from the outer peripheral edge of the lid material to the inner edge of the thermal bonding part S. Further, a hot melt layer was provided on the opening knob 2 so as not to straddle the thermal bonding portion S. Thereafter, cutting and punching were performed in the same manner as in Example 1 to produce a lid material 1 ′ in which a hot melt layer was also provided on the opening knob shown in FIG.

A lid material 1 '' shown in FIG. 5 was produced in the same manner as in Example 6 except that a spot-like spot adhesive part was partially provided with a hot-melt adhesive at the hot melt layer non-forming part of Example 6. .
In addition, the diameter of the spot-like spot adhesion part was a circle of 2 mm, and the distance from the adjacent spot-like spot adhesion part was 3 mm, and it was formed along the center line of the doughnut-shaped hot melt layer non-formation part.

[Comparative Example 1]
The hot melt layer of Example 1 is mainly composed of an ethylene / vinyl acetate copolymer having a storage elastic modulus G ′ of 10 ⁷ to 10 ⁸ Pa and a vibration absorption coefficient tan δ of 0.2 to 0.4 at 30 ° C. The same lid material as in Example 1 was produced except that the melt adhesive was used.

[Comparative Example 2]
Except for sandwich lamination of the VMP surface of VMPET and the uncoated surface of single-sided coated paper while forming a polyethylene layer having a thickness of 10 μm by extruding low density polyethylene instead of the hot melt layer of Example 1, In the same manner as in Example 1, a lid member made of a laminate having a structure of <pattern printing / single-side coated paper / polyethylene layer / VMPET / DL / EP film> was produced.

[Comparative Example 3]
Example 2 except that the VMPET of VMPET and the non-coated side of one-side coated paper were laminated by a dry lamination method (DL) via a polyester-isocyanate adhesive instead of the hot melt layer of Example 2. In the same manner, a lid member made of a laminate having a configuration of <pattern printing / single-side coated paper / DL / VMPET / DL / EP film> was produced.

Using the cup-shaped paper container having a circular opening in the cup-shaped container body, the lid materials prepared in Examples 1 to 7 and Comparative Examples 1 to 3 were thermally bonded to the opening of the cup-shaped paper container, respectively. A test sample was prepared.
The material, size, and heat bonding conditions of the cup-shaped paper container were as follows.
<Paper cup>
Material: (outer surface) low density polyethylene / paper / medium density polyethylene (inner surface),
Use a cup-shaped paper container with foamed low-density polyethylene on the outer surface,
Was a medium density polyethylene surface on the inside.
Diameter: Inner diameter 96mmφ
<Thermal bonding conditions>
Temperature; 160 ° C Pressure; 1 MPa Time; 0.7 seconds

About the said test sample, the opening test was done and the dead hold property of the lid | cover material was evaluated. Further, the strength at the time of opening (hereinafter referred to as opening strength) was also measured. The evaluation method and evaluation criteria are as follows.
<Opening test method>
Using a tensile tester (manufactured by Shimadzu Corporation; Autograph AG-ISMD), the opening knob of the sample to be tested is chucked, and the cover material has an approximately peel angle with respect to the flange of the cup-shaped container body. The lid was peeled from the cup-shaped container body to the center of the cup-shaped container body (peeling distance 48 mm), and the dead hold property and the opening strength were measured (n = 5). As shown in FIG. 3, the dead-holding property of the cup-shaped container body in which the opening knob was first located after the test sample with the lid opened was left in an atmosphere at 20 to 25 ° C. for 1 minute. Of the intersections intersecting with a perpendicular hanging from the lid material peeled on the line connecting the outer edge A and the center B of the cup-shaped container body, the intersection C closest to the outer edge A of the cup-shaped container body and the outer edge A of the cup-shaped container body The vertical height h from the tip of the unsealing knob of the unsealed lid material to the horizontal plane formed by the flange was measured and used as an evaluation index for dead hold property.
(Evaluation criteria for dead hold)
A: The average value of the length l of the outer edge A and the intersection C is 25 mm or more.
(Triangle | delta): The average value of the length l of the outer edge A and the intersection C is 10 mm or more and less than 25 mm.
X: The average value of the length l of the outer edge A and the intersection C is less than 10 mm.

  The results are shown in Table 1.

  As shown in Table 1, good dead hold properties were obtained for Examples 1 to 7, and it was possible to easily pour hot water into the cup-shaped container body from the pouring port 22. Thereafter, when the opened piece 1a of the lid material opened again was returned to the original position, the lid could be easily closed, and good resealability was obtained. However, in Comparative Examples 1 to 3, the length 1 between the outer edge A and the intersection C is 10 mm or less, and the lid material peeled off with one hand must be folded and pressed into the cup-shaped container body, which is troublesome. In addition, there was a risk of getting hot water. Further, in Examples 6 and 7, there is no possibility that the hot melt adhesive forming the hot melt layer melts and adheres to the hot plate when thermally bonded to the opening of the cup-shaped paper container. In Example 7, the outer peripheral edge of the lid member did not lift up between the paper layer and the inner layer or the intermediate layer, and the appearance was good.

DESCRIPTION OF SYMBOLS 1 Cover material 1a Opening piece 2 Opening knob 10 Paper layer 11 Hot melt layer 12 Intermediate layer 13 Inner layer 14 Light shielding layer 15 Hot melt layer non-formation part 16 Thermoplastic resin layer 17 Spot adhesion part 20 Cup-shaped container main body 21 Flange 22 The pouring gate A The outer edge of the cup-shaped container body where the opening knob was initially located B The center of the cup-shaped container body C Of the intersections intersecting with the perpendicular hanging from the lid material peeled off on the line connecting A and B, Intersection closest to A h Vertical length from the tip of the opening knob of the unsealed lid material to the horizontal plane formed by the flange l Length connecting A and C S Thermal bonding section

Claims (6)

In a lid made of a laminate that does not include a metal foil layer that seals the opening of the cup-shaped container body,
A lid material, wherein the laminate has a configuration in which a paper layer and an inner layer are laminated via a hot melt layer, and the hot melt layer is formed of a hot melt adhesive having viscoelasticity. The hot melt adhesive comprises a thermoplastic resin and a tackifier, the measurement temperature is T, the storage elastic modulus of the hot melt adhesive measured at the measurement temperature T is G ′, and the loss elastic modulus Is G ″ and the vibration absorption coefficient (tan δ) is defined as [tan δ = G ″ / G ′], the vibration absorption coefficient (tan δ) is 4 in the measurement temperature range of 0 ° C. ≦ T ≦ 50 ° C. The lid material according to claim 1, which is 0.0 × 10 ⁻¹ or more. The lid according to claim 1 or 2, wherein the laminate is formed by laminating an intermediate layer between the hot melt layer and the inner layer or the paper layer and the hot melt layer. The lid material according to any one of claims 1 to 3, wherein a hot melt layer non-forming portion from which the hot melt layer is removed is provided on an outer peripheral edge of the lid material. The lid material according to claim 4, wherein a spot adhesive portion that is partially formed by the hot melt adhesive is provided in the hot melt layer non-forming portion. The thermoplastic resin layer is laminated | stacked on the side laminated | stacked with the said hot-melt layer of the said paper layer, and the side laminated | stacked with the said hot-melt layer of the said inner layer or the said intermediate | middle layer. Or the cover material of 5.

Images