JP4911792B2 - Cap with liner and bottle with cap - Google Patents

Description

  The present invention relates to a cap with a liner and a bottle with a cap, which are excellent in an opening property, a sealing property, a gas barrier property, and the like.

  Many metal caps and plastic caps used in glass bottles, aluminum bottle cans, PET bottles and the like use liner materials. In particular, a liner is essential for a metal cap, and synthetic resin is widely used for this liner. This metal cap is a method of repeatedly embossing several times on both sides of aluminum thin plate, tin thin plate, chrome plated thin plate, etc., making it a cap shell, putting molten resin in the cap shell, and embossing (In-shell mold method) is common.

  In addition, there are a method of inserting a foamed PE disk, a method of pouring vinyl sol and thermoforming, etc., but there are problems such as cost and hygiene, and the range of use is limited. The plastic shell molding method is almost the same. This in-shell mold method is efficient in the amount of liner used and has a good sealing property, but since the liner material is completely adhered to the cap shell, Friction with cap shell is relatively large. For this reason, the torque required for opening is large, and the problem that opening is difficult sometimes occurs.

  For this reason, a lubricant mainly composed of fatty acid amide is added to many liner materials. This lubricant is devised so that it can bleed to the liner surface, thereby reducing friction with the container mouth and opening with low torque. However, it is difficult to control the bleed amount of this lubricant, and if the amount of bleed is too small, it will not serve as a sufficient lubricant and a high opening force will be required, and if there is too much bleed, the lubricant will There is a problem of falling down and being regarded as a foreign object.

  To solve these problems, a two-layer liner as described later has been proposed. This is a method in which a resin having a high hardness and a flexible resin are bonded together, the sealing performance is held by a flexible resin layer, and the proper torque at the time of opening is a method based on the friction between the hard resin layer and the cap shell. Although this two-layer sheet liner exhibits good sealing properties, the sealing properties are not sufficient for contents that require long-term storage. The main factor is that a gas such as oxygen permeates through the liner and contributes to the deterioration of the contents.

  In general, the harder the plastic, the better the gas barrier property, but the liner material needs a certain degree of flexibility in order to maintain the sealing property between the container and the cap shell. For this reason, as the liner material, a material having a poor gas barrier property among general plastics is used. Cap liners for hot-filled products and liners for retort processing are in a state in which materials with particularly poor gas barrier properties must be used. Since a flexible material must be used as the liner material, methods and materials for improving the gas barrier property of the liner material have been proposed.

For example, conventionally, techniques described in Patent Documents 1 to 8 have been proposed.
These described techniques have several drawbacks as liner materials. For example, the liner material described in Patent Document 1 has a multilayer structure, and has a barrier layer and a flexible layer, but has a structure in which a thin film deposited polyethylene terephthalate film such as silicon oxide is in contact with a bottle mouth. . In this method, the vapor deposition layer is hard and the unevenness of the bottle opening cannot be sufficiently covered, so that sufficient sealing performance cannot be obtained.

  Patent Document 2 describes a method of attaching a barrier material to a cap shell or a middle foot packing by insert, sticking, vapor deposition, coating, or the like in a synthetic resin cap with a middle foot packing. This method can be produced, but is expensive. For example, insert molding becomes a high-cost cap because the manufacturing equipment is large and the production speed is remarkably inferior. Adhesion, application, and vapor deposition are similarly costly. Further, these cap liners cannot withstand retort processing.

  Patent Document 3 discloses a container lid having gas barrier properties and heat resistance. This technique is a cap that uses an elastomer composed of a crosslinked butyl rubber, PP resin, and liquid paraffin as a liner material, but is crosslinked in order to withstand retort processing. Therefore, the liner smells from the liner and is not suitable for food. Further, since the slipperiness is poor, it is not suitable as a liner for a cap such as a PP cap that rotates and opens.

  Further, in Patent Document 4, in a liner material composed of a sliding layer and a sealing layer, a non-volatile liquid is applied between the sliding layer and the cap shell, so that the close contact between the cap shell and the liner is completed, oxygen, etc. This is a method of preventing gas permeation. In this method, the liner is in close contact with the cap shell in a state where an internal pressure is applied to the container with nitrogen, carbon dioxide gas or the like, and a good sealing property is exhibited. Further, since the liner is also in contact with the cap shell with a non-volatile liquid, it can be freely opened and opened with a low torque. However, when the container is at normal pressure or in a reduced pressure state, there is a problem that the close contact between the cap shell and the liner is not good and the barrier effect of the non-volatile liquid does not appear.

  Moreover, the liner material used for the aluminum cap used for a bottle can, a glass bottle, a PET bottle etc. uses the polyolefin liner which has polyethylene as a main component. In addition, styrene elastomers are frequently used for those requiring heat resistance such as retort treatment. These liner materials are often formed by an in-shell mold method. Since these liner materials are molded by an in-shell mold method, they have less material loss and are more economical than sheet liners. However, as described above, the liner is completely bonded to the cap shell. , Has the disadvantage of high opening torque.

  Even when a styrene-based or olefin-based liner material is in-shell molded on a synthetic resin cap shell such as PP resin, the opening torque tends to increase in the same manner. As a countermeasure against this, there is a general method in which a lubricant is added to the liner material, and the lubricant is bleed on the surface to provide lubricity, and the friction resistance between the container and the cap is lowered to lower the opening torque. In this method, it is difficult to keep the bleed of the lubricant constant, and if the amount of bleed is too small, the opening torque increases, and as described above, if the amount of bleed is large, the lubricant that bleeds on the surface of the liner is placed on the contents. It will fall and cause foreign matter.

  On the other hand, for example, a liner of a two-layer sheet shown in Patent Document 5 has been proposed. Similar to Patent Document 4, this liner is a laminate of a soft sealing layer and a hard sliding layer. When opening, the liner slides between the sliding layer and the top surface of the cap, resulting in low torque. It is a mechanism that can be. This liner material is excellent in sealing properties and openability, but since the liner is not in close contact with the top surface of the cap, oxygen or the like permeated through the liner deteriorates the contents, and the product cycle is long. There is a problem that the oxygen barrier property is insufficient.

JP 2000-344269 A JP 2001-192057 A JP 2002-160759 A JP 2008-50031 A Japanese Patent Laid-Open No. 2007-119059 Japanese Patent Laid-Open No. 2003-122013 JP 2008-174249 A JP 2004-1862 A

  As described above, in the case of a cap made of metal such as aluminum or tinplate, a liner is always provided in order to completely seal the container. A liner cap is also provided in a resin cap that requires high sealing performance. These liner materials are required to have a certain degree of flexibility in order to completely seal fine irregularities at the mouth of a container (glass bottle, PET bottle, bottle can, etc.). When this flexibility is required for plastics and elastomers, the greater the flexibility (softer), the more generally the gas barrier property is inferior and the heat resistance tends to decrease.

When the gas barrier property is lowered, there is a problem that the oxidative deterioration of the contents is promoted and the shelf life cannot be made long. Moreover, in the liner which cannot endure a retort process, the use application is limited.
In addition, since a flexible liner material is poorly slipped, a cap that can be rotated and opened has a high opening torque, which is a major cause of complaints. As a countermeasure against this, as described above, a method is adopted in which a lubricant is added to the liner material to improve the slipperiness and lower the opening torque.

  However, in this case, the control of the lubricant is not good, and even if the lubricant is used, the opening torque becomes high, or the amount of the lubricant is too much, causing the lubricant to fall on the contents and causing a complaint. To do. On the other hand, as a countermeasure against this, Patent Document 1 proposes a multilayer sheet liner material. This is because the liner material is divided into a sliding layer and a sealing layer and bonded together, a hard resin such as PP resin is in contact with the cap shell as a sliding layer, and a soft resin such as elastomer is used as a sealing layer as a bottle. It comes in contact with the mouth and maintains the sealing property.

  In this case, since the opening of the cap slips between the cap shell and the sliding layer of the liner, it is not necessary to add a lubricant to the liner material, so that there is no problem with the lubricant for controlling the opening torque. Absent. However, since this method slides between the cap shell and the liner, the liner and the cap shell are not in close contact with each other, so that gas such as oxygen escapes from between the cap shell and the liner through the top of the liner. Because it deteriorates the contents, it is not suitable for long-term storage.

  As one of the improvements, Patent Document 4 proposes a method of applying a nonvolatile organic liquid between the cap shell and the liner. This method is characterized in that the liner and the cap shell are brought into close contact with each other and slid between the cap shell and the liner at the time of opening to obtain a stable opening torque value. In this method, what is filled in a container such as a glass bottle or a PET bottle is in an internal pressure state, and good results are obtained when the liner is always pushed from the inside to the cap shell. However, as described above, when the filled state is normal pressure or negative pressure, a gap is formed between the shell and the liner, gas permeation from the top surface occurs, and deterioration of the contents is promoted. There is.

  Patent Document 6 proposes a liner having a structure in which a material having low oxygen permeability such as nylon is used as an oxygen shielding sheet between the packing material and the cap shell. With this method, a non-slip barrier material such as nylon directly contacts the cap shell, thereby increasing the opening torque. Further, when the barrier layer is not coated in this way, the barrier material comes into contact with moisture, thereby causing deterioration of gas barrier properties and physical properties, so that sufficient performance cannot be exhibited.

  In addition, a two-layer liner (including a sheet mold liner) in which a sliding layer and a sealing layer are bonded as described in Patent Document 5 shows a good opening property, but is high as described above. It is not sufficient as a liner material for caps that require gas barrier properties. A possible cause is that the structure between the sheet mold liner and the cap shell slides when the cap is opened, so that gas such as oxygen passes between the cap shell and the liner, and the liner This is considered to deteriorate the contents through the material.

  For this reason, a structure in which the sliding layer has a certain gas barrier property has been proposed. For example, in the above-mentioned Patent Document 7, there is a container lid composed of an air barrier material which is an oxygen barrier sheet such as EVOH resin (ethylene-vinyl alcohol copolymer resin) and nylon, and an elastic resin material such as polyethylene as a packing material. Proposed. However, barrier materials such as EVOH resin and nylon have a problem that gas barrier properties are lowered by absorbing moisture. In addition, since many of these air barrier materials are poorly slipped, it is difficult to control the slip when used as a sliding layer of a two-layer sheet. For this reason, there is a problem that it is difficult to keep the opening torque within a desired constant value.

  In addition, these air barrier materials must be completely bonded to the packing material. Generally, air barrier materials such as EVOH resin and nylon are sufficiently used as polyethylene and elastomer used as the packing material (sealing layer). Adhesive strength cannot be obtained. Therefore, the conventional method in which the air blocking material is made of a barrier material and the packing material is made of polyethylene or the like has many difficulties in terms of production, cost, and practical use for practical use.

  Moreover, in the said patent document 8, the method of blending a fixed quantity of barrier resins, such as EVOH resin, with the olefin resin of the inner cap of the resin cap, and improving the gas barrier property is proposed. This method is effective to some extent for bottle bottles with high dimensional accuracy such as PET bottles, but is not sufficient for containers with insufficient bottle mouth accuracy such as glass bottles and reseal cans.

  For these inner stopper type liners, the accuracy of the inner diameter of the bottle mouth is important, but glass bottles, resealable cans, etc. cannot improve the accuracy of the inner stopper as well as PET bottles due to the manufacturing method. On the other hand, the gas barrier resin such as EVOH resin has high hardness, so when it is blended with resin such as polyethylene, it becomes harder. Is not preferable as a packing for a normal container.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a cap with a liner and a bottle with a cap that are excellent in unsealing performance, sealing performance, and gas barrier properties, and have good productivity and practicality. To do.

The present invention employs the following configuration in order to solve the above problems. That is, the cap with a liner of the present invention is a cap with a liner that seals the mouth of the bottle main body, the cap main body comprising a top plate portion and a cylindrical peripheral wall portion that hangs down from the periphery of the top plate portion, and the top. A liner provided on the inner surface of the plate portion, and the liner is arranged in contact with the inner surface of the top plate portion, and is laminated on the sliding layer and is more flexible than the sliding layer. A sealing layer, an intermediate layer disposed between the sliding layer and the sealing layer and having a gas barrier property, and an adhesive provided between the intermediate layer and the sliding layer or the sealing layer to bond them together And the intermediate layer is a material having a lower adhesive strength with the sealing layer than the sliding layer, and the adhesive layer is formed of the same material as the sliding layer, and the sliding Layer sheet, the intermediate layer, and the adhesive layer are bonded with an adhesive. Characterized in that it is a click.

This cap with a liner is provided with an adhesive layer that is provided between an intermediate layer having gas barrier properties and a sliding layer or a sealing layer and adheres them. For example, the intermediate layer and the sealing layer are directly bonded to each other. Even when sufficient adhesive strength cannot sometimes be obtained, good adhesion can be obtained by adhering the intermediate layer and the sealing layer via the adhesive layer.
In addition, a resin having high hardness is used as a sliding layer in contact with the inner surface of the cap shell, and an elastic body that is completely adhered to it is used as a sealing layer (mainly an elastomer). A gas barrier layer is provided between the sliding layer and the sealing layer. By interposing a certain intermediate layer, a liner having excellent gas barrier properties can be obtained. That is, the liner is made into a multilayer in the order of a sliding layer, an intermediate layer, an adhesive layer, and a sealing layer, and by providing the intermediate layer with a gas barrier property, the sealing property, gas barrier property, openability, and retort property It is possible to provide an excellent liner material. If the intermediate layer is bonded between the sealing layer and the sliding layer via an adhesive layer, the sliding layer is made into a multilayer and the intermediate layer is inserted through the adhesive layer therein It doesn't matter.

Moreover, the cap with a liner of the present invention is characterized in that the intermediate layer is formed of a metal foil.
That is, in this cap with a liner, since the intermediate layer is formed of a metal foil such as an aluminum foil, a very high gas barrier property can be obtained.

The cap with a liner of the present invention is characterized in that the intermediate layer is formed of a gas barrier resin.
That is, in this cap with a liner, since the intermediate layer is formed of a gas barrier resin such as EVOH resin, the intermediate layer can be formed by extrusion molding, which is low in cost and excellent in productivity. .

In the cap with a liner of the present invention, the intermediate layer is made of a material having lower adhesive strength with the sealing layer than the sliding layer, and the adhesive layer is made of the same material as the sliding layer. It is characterized by.
That is, in this cap with a liner, since the adhesive layer is formed of the same material as the sliding layer having good adhesion to the intermediate layer, it is easy to produce a laminate, and the cost can be reduced. .

Moreover, the cap with a liner of the present invention is characterized in that the sealing layer is formed by molding.
That is, in this cap with a liner, since the sealing layer is formed by molding, sealing layers having various shapes corresponding to the mouth shape of the bottle body can be easily obtained.

Moreover, the cap with a liner of the present invention is characterized in that the sealing layer is formed of a styrene elastomer.
That is, in this cap with a liner, the sealing layer is formed of a styrene-based elastomer that is a blend of low MFR SEBS (styrene-ethylene-butylene-styrene), PP resin, liquid paraffin, etc. A liner is obtained.

The bottle with a cap of the present invention is a bottle provided with a cap, and the cap is the cap with a liner of the present invention.
That is, in this bottle with a cap, since the cap is the cap with the liner of the present invention, it has not only good opening and sealing properties but also excellent gas barrier properties and productivity.

The present invention has the following effects.
That is, according to the cap with the liner and the bottle with the cap according to the present invention, the adhesive layer is provided between the intermediate layer having gas barrier properties and the sliding layer or the sealing layer, and adheres to these. Good adhesiveness of the intermediate layer can be obtained through the layer, and it is good with high adhesiveness by the adhesive layer as well as improved sealing performance by the sliding layer, sealing property by the sealing layer, and gas barrier property by the intermediate layer. Productivity can be obtained.

In one Embodiment of the cap with a liner and bottle with a cap concerning this invention, it is the side view which fractured | ruptured a part which shows a cap. In this embodiment, it is sectional drawing which shows a liner. In this embodiment, it is an expanded sectional view of the principal part which shows a bottle with a cap.

  Hereinafter, an embodiment of a cap with a liner and a bottle with a cap according to the present invention will be described with reference to FIGS. 1 to 3.

  As shown in FIGS. 1 to 3, the cap 1 according to the present embodiment is a cap with a liner that seals a base portion (mouth portion) 3 of a bottle body 2, and includes a top plate portion 4 and a peripheral edge of the top plate portion 4. A bottomed cylindrical resin shell or metal cap shell (cap body) 6, and a liner (cap liner) 7 provided on the inner surface of the top plate portion 4; It has.

Moreover, the bottle 8 with a cap of this embodiment is equipped with the said cap 1 in the state fastened around the nozzle | cap | die part 3 of the bottle main body 2, as shown in FIG.
The cap shell 6 is formed from a resin-molded material such as a polyolefin resin or a polystyrene resin, or processed from a plate material of aluminum or an aluminum alloy.

  The liner 7 includes a sliding layer 7a disposed in contact with the inner surface of the top plate portion 4, a sealing layer 7b that is laminated on the sliding layer 7a and is more flexible than the sliding layer 7a, and is sealed with the sliding layer 7a. An intermediate layer 7c having a gas barrier property is provided between the layer 7b and an adhesive layer 7d provided between the intermediate layer 7c and the sealing layer 7b to adhere them. That is, the sealing layer 7b is laminated on the sliding layer 7a via the intermediate layer 7c and the adhesive layer 7d.

The intermediate layer 7c is a material having lower adhesive strength with the sealing layer 7b than the sliding layer 7a, and has a higher gas barrier property than the sliding layer 7a and the sealing layer 7b, such as a metal foil or a gas barrier. It is made of a functional resin.
The adhesive layer 7d is preferably made of the same material as the sliding layer 7a.
The sealing layer 7b is preferably formed by molding and is formed of a styrene elastomer.

  That is, the barrier material inserted as the intermediate layer 7c is preferably an organic gas barrier resin such as EVOH resin (ethylene-vinyl alcohol copolymer resin), PA (nylon), PAN (polyacrylonitrile), but aluminum, iron, tin, etc. The metal sheet (metal foil) may be used. In this case, when a metal sheet is used as the intermediate layer 7c, heat-resistant PET film, PP film, epoxy phenol and other baking paints are suitable for being bonded to both surfaces, An adhesive layer 7d of PP film is preferably formed on the surface so as to adhere to the sealing layer 7b.

  In addition, you may apply | coat synthetic resin paints, such as an epoxy phenol, as the contact bonding layer 7d to metal sheets, such as aluminum, iron, and tin which were employ | adopted as the intermediate | middle layer 7c. In this case, it is preferable that an adhesive layer 7d of a paint that can be adhered to the sealing layer 7b or a paint to which an adhesive component is added is formed on the surface on the base part 3 side in order to adhere to the sealing layer 7b.

  Various elastomers are suitable for the sealing layer 7b, but olefin elastomers and styrene elastomers are suitable in terms of price, heat resistance, adhesiveness to the sliding layer, moldability, and the like. In particular, as described above, a styrene elastomer that is a blend of a styrene block copolymer, a PP resin, and a soft material such as liquid paraffin is preferable in consideration of the retort treatment.

  The SBC (hydrogenated styrene-conjugated diene block copolymer rubber) used in this elastomer is SEBS (styrene-ethylene-butylene-styrene: styrene / ethylene-butylene / styrene: low MFR (0.01 ° C / 10 min or less at 230 ° C.-5 kg): Hydrogenated styrene-butadiene block copolymer rubber) or SEPS (styrene-ethylene-propylene-styrene: hydrogenated styrene-isoprene block copolymer rubber using isoprene polymer block). Other SBCs such as SIS, SBS, and SIBS have insufficient heat resistance and cannot withstand retort processing. As the soft material used for the retortable styrene-based elastomer, liquid paraffin is generally used, but polybutene or the like can also be used.

Next, an example of a method for manufacturing the liner 7 and the cap 1 of this embodiment will be described.
First, a sheet in which both sides of the EVOH resin as the intermediate layer 7c are sandwiched with PP (polypropylene) resin as the sliding layer 7a and the adhesive layer 7d is formed by coextrusion. At this time, in order to adhere the EVOH resin and the PP resin, a modified olefin resin is inserted as an adhesive to form a sheet. Therefore, this sheet has a configuration of PP resin (sliding layer 7a) / adhesive / EVOH resin (intermediate layer 7c) / adhesive / PP resin (adhesive layer 7d).

This is the same even when the intermediate layer 7c which is a gas barrier layer is PA or PAN.
In the present embodiment, the thickness of the sheet is set to 0.4 mm, for example. Further, this is punched out into a disk having a diameter of 37.6 mm, inserted into the cap shell 6 of a PP cap made of aluminum having a nominal diameter of 38 mm, and the above-mentioned styrene elastomer is used as the sealing layer 7b by an in-shell mold type liner molding machine. Mold on the sheet inserted in

  In other words, the test liner is melted from the extruder into a strand and cut into a certain amount, dropped into almost the center of the inserted sheet disk in the cap shell 6, and immediately molded into a certain shape with a cooled mold. The liner 7 is pushed.

  When the intermediate layer 7c is an aluminum foil having a thickness of 100 μm, an epoxy phenol paint is applied and baked on both sides as the sliding layer 7a and the adhesive layer 7d. In this case, the one-side coating used as the adhesive layer 7d uses a coating in which a modified polyolefin is added to the paint so that the PP resin as the sliding layer 7a can be adhered. This was punched into a Φ37.6 mm disk in the same manner as described above, inserted into the cap shell 6 of a PP cap made of aluminum having a nominal diameter of 38 mm, and the above styrene elastomer was used as the sealing layer 7b with an in-shell mold type liner molding machine. Molding is performed on the sheet inserted into the shell 6.

  As described above, the cap 1 of the present embodiment includes the adhesive layer 7d provided between the intermediate layer 7c having gas barrier properties and the sliding layer 7a or the sealing layer 7b. Even when sufficient adhesive strength cannot be obtained when 7c and the sealing layer 7b are directly bonded, good adhesion is obtained by bonding the intermediate layer 7c and the sealing layer 7b via the adhesive layer 7d. be able to.

  Further, a resin having high hardness or the like is used as the sliding layer 7a in contact with the inner surface of the shell, and an elastic body that is completely in close contact therewith is used as the sealing layer 7b, and an intermediate layer that is a gas barrier layer between the sliding layer 7a and the sealing layer 7b. By interposing 7c, a liner having excellent gas barrier properties can be obtained. That is, the liner 7 is made into a multilayer in the order of the sliding layer 7a, the intermediate layer 7c, the adhesive layer 7d, and the sealing layer 7b so that the intermediate layer 7c has gas barrier properties. It is possible to provide a liner material excellent in plugging property and retort property. If the intermediate layer 7c is bonded between the sealing layer 7b and the sliding layer 7a via the adhesive layer 7d, the sealing layer 7b or the sliding layer 7a is formed in multiple layers, and the adhesive layer is included therein. A structure in which the intermediate layer 7c is inserted through 7d may be used.

In addition, when the intermediate | middle layer 7c is formed with metal foil, such as aluminum foil, very high gas barrier property can be obtained.
Further, when the intermediate layer 7c is formed of a gas barrier resin such as EVOH resin, the intermediate layer 7c can be formed by molding, which is low in cost and excellent in productivity.

Furthermore, since the adhesive layer 7d is formed of the same material as the sliding layer 7a having good adhesiveness with respect to the intermediate layer 7c, it is easy to produce a laminate and to reduce the cost.
Moreover, since the sealing layer 7b is formed by molding, the sealing layer 7b having various shapes corresponding to the shape of the mouth portion (base portion 3) of the bottle body 2 can be easily obtained.

Furthermore, by forming the sealing layer 7b with a styrene-based elastomer that is a blend of SEBS (styrene / ethylene-butylene / styrene), the liner 7 that can withstand retort treatment is obtained.
Therefore, the bottle 8 having the cap 1 has not only good opening and sealing properties but also excellent gas barrier properties and productivity.

Next, the results of evaluating the cap liner, the cap, and the bottle with the cap according to the present invention by the actually produced examples will be described in detail.
As an example of the present invention, a cap provided with the liner of the present embodiment was produced as follows.

<Example 1, comparative example 1>
An aluminum plate having a thickness of 0.24 mm whose inner and outer surfaces were baked and coated with a synthetic resin was molded into a cap shell of a nominal 38PP cap. In addition, as a sliding layer, an intermediate layer, and an adhesive layer of the liner, three layers of PP resin, EVOH resin, and PP resin (in which PP resin is arranged on both sides of EVOH resin) (exactly EVOH resin and PP resin) The sheet was molded with a thickness of 500 μm because there was an adhesive in between. Furthermore, a sheet of TPS (styrene elastomer) having a thickness of 300 μm was bonded to this sheet as a sealing layer. This was punched out into a disk having a diameter of 37.6 mm and inserted into a cap shell, and this was taken as Example 1-1.

  In another embodiment, the above three-layer sheet is punched into a disk having a diameter of 37.6 mm and inserted into a cap shell, and TPS (styrene elastomer) is used as a sealing layer in a liner molding machine. What was shape | molded by this was made into Example 1-2 and Example 1-3.

In addition, samples using MX nylon and aluminum foil as an intermediate layer having gas barrier properties were used as Examples 1-4 and 1-5, respectively.
In addition, as a comparative example, the sliding layer is a PP single layer and a sealing layer is a TPS sheet (Comparative Example 1-1), the sliding layer is a PP single layer and the sealing layer is a molded TPS. (Comparative Example 1-2), the sliding layer is an EVOH single layer and the sealing layer is molded from TPS (Comparative Example 1-3), only the sealing layer of the TPS mold (Comparative Example 1-4), Also, a molded olefin elastomer TPO having only a sealing layer (Comparative Example 1-5) was used.

  These Examples and Comparative Examples were capped in a 38 mm bottle can (340 ml) filled with 275 ml of an aqueous solution containing about 400 ppm of vitamin C. This capping was performed at a head pressure of 1000N. Further, liquid nitrogen was dropped into the head space immediately before capping, and the internal pressure was adjusted to approximately 0.1 MPa. The thus-capped product was subjected to retort treatment at 123 ° C. for 20 minutes, stored in a constant temperature room at 55 ° C., and the following evaluation test was performed.

  In addition, the liners of the present examples and comparative examples, if necessary, as a coloring material, 0.5% or less of titanium oxide, 0.1% or less of a hindered phenol stabilizer as a stabilizer, and fatty acid amide as a lubricant Less than 1% of lubricant is added.

<Method of evaluation test>
(Oxygen barrier properties)
Among the gas barrier properties, in particular, in order to examine the amount of decrease in vitamin C due to oxygen permeation as an oxygen barrier property, the sample was left in a constant temperature room at 55 ° C. for 2 months, and the amount of change in vitamin C was examined with an automatic potential titrator.
"Evaluation criteria"
(In all the evaluation criteria described below, ◎ ○ △ is judged as good and × is judged as defective. In the evaluation of each characteristic, those including even one are regarded as defective.)
◎ = Decrease rate <3%
○ = Decrease rate ≧ 3 <6%
Δ = Decrease rate ≧ 6 to <10%
× = Decrease rate ≧ 10%
(3 samples each)

(Sealing)
For the bottle cans filled and retorted as described above, the internal pressure before and after the retort was measured, and the presence or absence of leakage was confirmed. Furthermore, in contrast to the case where no leakage was observed, after dropping vertically onto an iron plate having a surface with an inclination angle of 10 ° from a height of 30 cm and 10 cm, the leakage of the internal solution and the change in internal pressure caused the leakage. The presence or absence was confirmed.
"Evaluation criteria"
◎ = No leakage after dropping 30cm ○ = No leakage at 10cm, but leakage was observed at 30cm △ = No leakage at retort treatment, but leakage was observed at 10cm drop × = Leakage was observed at retort processing (10 samples each)

(Opening torque)
The above-described filled retort-treated product was left in a thermostatic chamber at 50 ° C. for 1 month and then taken out, and the opening torque was measured. In the measurement, a torque value (first torque) necessary for the cap to rotate was measured. The torque value (second torque) when the aluminum bridge is cut is excluded. The opening torque has an appropriate range. If the opening torque is too high, it is difficult to open the opening. If the opening torque is too low, the cap may loosen during transportation and handling, and leakage may occur.

"Evaluation criteria"
◎ = 50 to 150 N · cm (optimum positive torque value)
○ = 150 to 200 N · cm (slightly high torque value)
○ = 30-50 N · cm (Slightly low torque value)
× => 200 N · cm (torque value too high)
× = <30 N · cm (torque value too low)

In addition, the detailed structure of each Example and a comparative example and its evaluation result are shown below.
Configuration and Evaluation of Example 1-1 Sliding layer / intermediate layer / adhesive layer = sheet having a three-layer structure of PP resin (200 μm) / EVOH resin (20 μm) / PP resin (200 μm). PP resin also contains an adhesive. Figures in parentheses are component thicknesses.
Sealing layer = TPS (a) (400 μm) = Styrenic elastomer (PP resin, liquid paraffin and SEPS (styrene / ethylene / propylene / styrene) blend) sheet. However, the MFR of SEPS is 0.0 g / 10 min (200 ° C.-5 kg).
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.
The MFR (melt flow rate) is measured under test conditions based on JIS K 7210 condition H (test temperature 200 ° C., nominal load 5.00 kg). In addition, the notation in this case is (200 ° C.-5 kg).

-Configuration and evaluation of Example 1-2 Sliding layer / intermediate layer / adhesive layer = same configuration as Example 1-1.
Sealing layer = TPS (a) (400 μm) = same material as Example 1-1. However, the manufacturing method is based on the in-shell mold method. The thickness indicates the thickness in contact with the container lip. Moreover, the center part which does not participate in a seal | sticker has a structure which becomes thin. (The in-shell mold method of the sealing layer described below has the same thickness and structure as in this example.)
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

Structure and Evaluation of Example 1-3 Sliding layer / intermediate layer / adhesive layer = sheet having a three-layer structure of PP resin (180 μm) / EVOH resin (40 μm) / PP resin (180 μm). PP resin also contains an adhesive. Figures in parentheses are component thicknesses.
Sealing layer = TPS (b) (400 μm) = Styrenic elastomer (PP resin, liquid paraffin, SEBS styrene / ethylene / butylene / styrene blend). However, SEFR has an MFR of 0.0 g / 10 min (200 ° C.-5 kg).
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

-Configuration and evaluation of Example 1-4 Sliding layer / intermediate layer / adhesive layer = sheet having a three-layer structure of PP resin (100 μm) / Al (20 μm) / PP resin (100 μm). PP resin also contains an adhesive. Al is an aluminum foil.
Sealing layer = TPS (a) (400 μm) = same material as Example 1-1. However, the manufacturing method is based on the in-shell mold method.
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

Structure and Evaluation of Example 1-5 Sliding layer / intermediate layer / adhesive layer = sheet having a three-layer structure of PP resin (180 μm) / MXNy (50 μm) / PP resin (180 μm). PP resin also contains an adhesive. MXNy is MX nylon.
Sealing layer = TPS (a) = same material as Example 1. However, the manufacturing method is based on the in-shell mold method.
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

Configuration and Evaluation of Example 1-6 Sliding layer / intermediate layer / adhesive layer = E / P (a) (5 μm) / Al (100 μm) / E / Pb (5 μm) sheet having a three-layer structure. Al is an aluminum foil. The E / P (a) layer is an epoxy phenol baking paint. The E / P (b) layer is an epoxy phenol baking paint to which a PP adhesive component is added at a solid content ratio of 5%.
Sealing layer = TPS (a) = same material as Example 1. However, the manufacturing method is based on the in-shell mold method.
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

Configuration and Evaluation of Example 1-7 Sliding layer / intermediate layer / adhesive layer = sheet having a three-layer structure of PP resin (20 μm) / Al (100 μm) / E / Pb (5 μm). PP resin also contains an adhesive. Al is an aluminum foil. E / P (a) is an epoxy phenol baking coating to which 5% of a modified olefin resin is added as a lubricant. E / P (b) is an epoxy phenol baking paint in which a PP adhesive component is added at a solid content ratio of 5%.
Sealing layer = TPS (a) (400 μm) = same material as in Example 1. However, the manufacturing method is based on the in-shell mold method.
"Evaluation results": Oxygen barrier properties, sealing properties, and openability are good.

Structure and evaluation of Example 1-8 Sliding layer / intermediate layer / adhesive layer = same structure as Example 1-1.
Sealing layer = TPS (c) (400 μm) = Styrene elastomer is the same as in Example 1. However, the MFR of the SEPS used was 1.0 g / 10 min (200 ° C.-5 kg), and the sealing layer was formed by an in-shell mold method.
"Evaluation results": Oxygen barrier properties and openability are good, but sealing properties are slightly inferior.

-Configuration and evaluation of Example 1-9 Sliding layer / intermediate layer / adhesive layer = same configuration as Example 1-1.
Sealing layer = TPO (a) (400 μm) = Use of olefin elastomer (blended product of LLDPE and EPR 20%). However, the MFR of the LLDPE used was 1.0 g / 10 min (200 ° C.-5 kg), the density was 0.928, and the sealing layer was molded by an in-shell mold method.
“Evaluation result”: The opening performance is slightly good, but the sealing performance is slightly inferior. Good oxygen barrier properties.

-Composition and evaluation of Comparative Example 1-1 Sliding layer = PP (600 µm) single layer structure sheet. In addition, () is a structural thickness.
Sealing layer = TPS (a) (400 μm) = Styrenic elastomer (a blend of PP resin, liquid paraffin and SEPS). However, the MFR of SEPS is 0.0 g / 10 min (200 ° C.-5 kg). Moreover, the sliding layer and the sealing layer were simultaneously formed by a coextrusion method.
“Evaluation results”: Sealing and unsealing properties are good, but oxygen barrier properties are poor.

-Configuration and evaluation of Comparative Example 1-2 Sliding layer = sheet having a single layer structure of PP (400 µm). In addition, () is a structural thickness.
Sealing layer = TPS (a) (400 μm) = styrene elastomer (blend of PP resin, liquid paraffin and SEPS). However, the MFR of SEPS is 0.0 g / 10 min (200 ° C.-5 kg). The sealing layer was formed by an in-shell mold method.
“Evaluation results”: Sealing and unsealing properties are good, but oxygen barrier properties are poor.

-Configuration and Evaluation of Comparative Example 1-3 Sliding layer = EVOH (300 µm) single layer structure sheet. However, the modified olefin resin was applied to the surface to be bonded to the sealing layer. The thickness also includes an adhesive.
Sealing layer = TPS (a) (400 μm) = Styrene elastomer is the same as in Example 1-1. The sealing layer was formed by an in-shell mold method.
"Evaluation results": Oxygen barrier property and openability are good, but the sealing property is not stable.

Configuration and Evaluation of Comparative Example 1-4 Liner = Single liner by in-shell mold method using TPS (a) (700 μm).
“Evaluation result”: The oxygen barrier property is slightly good and the sealing property is good, but the opening torque is high.

Structure and Evaluation of Comparative Example 1-5 Liner = Single liner by in-shell mold method of TPO (a) (700 μm).
"Evaluation result": The oxygen barrier property is inferior and the opening torque is too low.

Next, a cap containing a liner similar to that in Example 1 was used, and the same evaluation was performed by changing the filling and sterilization conditions.
"Filling method"
Similarly to Example 1, 290 ml of an 85 ° C. aqueous solution containing about 400 ppm of vitamin C was similarly filled in a bottle can (with a full capacity of 340 ml) having a nominal diameter of 38 mm and capped. This capping was performed at a head pressure of 1000N. Further, liquid nitrogen was dropped into the head space immediately before capping, and the internal pressure was adjusted to approximately 0.1 MPa. What was capped in this manner was stored in a constant temperature room at 55 ° C., and the following evaluation test was performed. In addition, the liner similar to the comparative example in the said Example 1 was used as a comparative example.

<Method of evaluation test>
(Oxygen barrier properties)
Among the gas barrier properties, in particular, in order to examine the amount of decrease in vitamin C due to oxygen permeation as an oxygen barrier property, the sample was left in a constant temperature room at 55 ° C. for 2 months, and the amount of change in vitamin C was examined with an automatic potential titrator. In addition, the thing immediately after filling was measured as control.
"Evaluation criteria"
◎ = Decrease rate <3%
○ = Decrease rate ≧ 3 <6%
Δ = Decrease rate ≧ 6 to <10%
× = Decrease rate ≧ 10%
(3 samples each)

(Sealing)
With respect to the bottle cans filled and heat-treated as described above, the internal pressure before and after the heat treatment was measured to check for leakage. Furthermore, in contrast to the case where no leakage was observed, after dropping vertically onto an iron plate having a surface with an inclination angle of 10 ° from 20 cm and 30 cm in an inverted state, leakage of the internal solution and change of internal pressure caused leakage of the leakage. The presence or absence was confirmed.
"Evaluation criteria"
◎ = No leakage due to 30cm drop ○ = No leakage at 20cm, but leakage was observed at 30cm △ = No leakage by heat treatment, but leakage was observed by 20cm drop × = Leakage was observed by heat treatment (Sample Number 10)

(Opening torque)
The above-mentioned filled and heat-treated product was left in a 55 ° C. constant temperature room for one month and then taken out, and the opening torque was measured. Measurement and evaluation are the same as in Example 1.

"Evaluation results"
Examples 2-1 to 2-7: Good oxygen barrier properties, sealing properties, and plug-opening properties.
Examples 2-8 to 2-9: The oxygen barrier property is good, but the sealing property and the opening torque are slightly low.
Comparative Examples 2-1 to 2-2: The oxygen barrier property is inferior.
Comparative Example 2-3: The oxygen barrier property is good, but the opening torque is inferior.
Comparative Example 2-4: The oxygen barrier property is inferior. Opening torque is high.
Comparative Example 2-5: The oxygen barrier property is inferior.

  Thus, as shown in each of the above evaluations, in the comparative example, any one of the oxygen barrier properties, sealing properties, and plugging properties is poor, whereas in this example, the oxygen barrier properties, sealing properties are poor. Good results have been obtained for both the property and the openability.

  The technical scope of the present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Cap, 2 ... Bottle main body, 3 ... Base part (mouth part), 4 ... Top plate part, 5 ... Cylindrical peripheral wall part, 6 ... Cap shell (cap main body), 7 ... Liner, 7a ... Sliding layer, 7b ... Sealing layer, 7c ... Intermediate layer, 7d ... Adhesive layer, 8 ... Bottle with cap

Claims (6)

A cap with a liner that seals the mouth of the bottle body,
A cap body comprising a top plate portion and a cylindrical peripheral wall portion hanging from the periphery of the top plate portion;
A liner provided on the inner surface of the top plate portion,
A sliding layer in which the liner is disposed in contact with the inner surface of the top plate portion;
A sealing layer that is laminated on the sliding layer and is more flexible than the sliding layer;
An intermediate layer disposed between the sliding layer and the sealing layer and having gas barrier properties;
An adhesive layer provided between the intermediate layer and the sliding layer or the sealing layer to bond them ,
The intermediate layer is a material having lower adhesive strength with the sealing layer than the sliding layer,
The adhesive layer is formed of the same material as the sliding layer;
A cap with a liner, wherein the sliding layer, the intermediate layer, and the adhesive layer are a sheet disk bonded with an adhesive . The cap with a liner according to claim 1,
A cap with a liner, wherein the intermediate layer is formed of a metal foil. The cap with a liner according to claim 1,
A cap with a liner, wherein the intermediate layer is formed of a gas barrier resin. In the cap with a liner according to any one of claims 1 to 3 ,
A cap with a liner, wherein the sealing layer is formed by molding. In the cap with a liner as described in any one of Claim 1 to 4 ,
A cap with a liner, wherein the sealing layer is formed of a styrene elastomer. A bottle with a cap,
The said cap is a cap with a liner as described in any one of Claim 1 to 5 , The bottle with a cap characterized by the above-mentioned.

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