JP6123196B2 - Lid material - Google Patents

Description

  The present invention relates to a lid member. In particular, lids for packaging foods, beverages, pharmaceuticals, cosmetics, chemicals, etc. More specifically, lids for containers such as yogurt, jelly, pudding, syrup, retort foods such as porridge and soup, and chemicals The present invention relates to a lid used for a storage container for liquids such as goods and pharmaceuticals, semi-solids, and gel substances.

  Ordinary lids are difficult to remove due to adhesion of the contents, and often cause waste or dirt of the contents. In addition, when a fluorine material or silicone is used, although it has water repellency and adhesion prevention effects, it has poor heat sealing properties and is difficult to use as a lid material.

  In order to solve these problems, a layered product having a base material layer and a thermal adhesive layer, the thermal adhesive layer being laminated as the outermost layer on one side, and primary particles on the outermost side not adjacent to the other layer There is a cover material in which hydrophobic oxide fine particles having an average diameter of 3 to 100 nm are adhered, and the hydrophobic oxide fine particles form a porous layer having a three-dimensional network structure (Patent Document 1).

  However, although the above-mentioned lid material has hydrophobicity in the hydrophobic oxide particles themselves, the coating liquid itself that forms the hydrophobic oxide particles does not use a binder, so that the hydrophobic oxide particles are sufficient for the thermal adhesive layer. In particular, in the case of foods, there is a problem that safety cannot be sufficiently ensured because the hydrophobic oxide fine particles easily fall off and the hydrophobic oxide fine particles easily fall off, and the hydrophobic oxide fine particles enter into the contents of the food as foreign matters. In addition, the inorganic particles having a primary particle diameter of 3 to 100 nm that have been subjected to hydrophobic treatment have a problem that the dispersibility is poor and the productivity is remarkably deteriorated such as gelation.

  Known documents are shown below.

Japanese Patent No. 4348401

  The present invention has been made in view of the above-mentioned circumstances, has no risk of particle dropping, has excellent repellency such as water repellency while maintaining good sealing properties, and reduces the remaining amount of contents and prevents adhesion It is an object to provide a lid material that has an effect and good productivity.

In the invention according to claim 1 of the present invention, a base material layer, a heat seal varnish layer, and a hydrophobic agglomerated silica particle layer are sequentially laminated, and the hydrophobic agglomerated silica particle layer has an average particle size of 0.1 to 10 μm. Made of hydrophobic agglomerated silica particles whose surface is subjected to a hydrophobic treatment,
The hydrophobic aggregated silica particle layer is made of a mixture of the hydrophobic aggregated silica particles and an inorganic binder .

  The invention according to claim 2 of the present invention is such that the surface of the aggregate is subjected to a hydrophobic treatment with dimethylpolysiloxane or dimethylsiloxane, or any of dimethylsilyl, trimethylsilyl, aminoalkylsilyl, alkylsilyl, and methacrylsilyl. The lid according to claim 1, which is hydrophobically treated with such a functional group.

The invention according to claim 3 of the present invention is the lid according to claim 1 or 2, wherein the aggregate of silica particles is produced by a wet manufacturing method.

  The invention according to claim 4 of the present invention is the lid according to any one of claims 1 to 3, wherein the hydrophobic aggregated silica particles have a DBA value of 50 mmol / Kg or less.

In the invention according to claim 5 of the present invention, the inorganic binder is composed of a metal alkoxide represented by M (OR) n or a hydrolyzate of metal alkoxide, the metal (M) is Si, Al, Ti, R Is an alkyl group, and n is the valence of a metal (M), The lid | cover material of any one of Claim 1 to 4 characterized by the above-mentioned.

In the invention according to claim 6 of the present invention, beads comprising any one of nylon, acrylic resin, styrene resin, silicone, fluororesin, and silica having an average particle diameter of 1 to 50 μm are added to the heat seal varnish layer. It is a lid | cover material of any one of Claim 1 to 5 characterized by these.

The invention according to claim 7 of the present invention is that the acrylic resin beads are polymethyl methacrylate, polybutyl methacrylate, polyacrylate ester, polystyrene, crosslinked polymethyl methacrylate, crosslinked polybutyl methacrylate, crosslinked polyacrylate ester. The lid material according to claim 6 , which is any one of crosslinked polystyrene.

In the invention according to claim 8 of the present invention, a primer layer is provided between the base material layer and the heat seal varnish layer, and the primer layer comprises an ethylene-vinyl acetate copolymer resin, an acrylic resin, and an ester resin. The resin composition according to any one of claims 1 to 7, wherein the resin is made of any one of a vinyl acetate resin, a modified olefin resin, an imine resin, a polybutadiene resin, and an ethylene-acrylic acid copolymer resin. It is a lid.

The invention according to claim 9 of the present invention, any of claim 1 to 8, characterized in that the softening point of the heat-sealing varnish of the heat sealing varnish layer is lid, characterized in that at 110 ° C. or higher The lid material according to claim 1 .

In the invention according to claim 10 of the present invention, the lid material is a container lid material, and the hydrophobic agglomerated silica particle layer is broken by the seal to the seal part of the container, and the heat seal varnish layer starts from the crack. The heat seal varnish is melt-bonded to the seal portion of the container. The cover material according to any one of claims 1 to 9 .

  The lid material of the present invention has no repellent of foreign matters due to falling off of particles, has excellent repellency such as water repellency while maintaining good sealing properties, and has effects of reducing the remaining amount of contents and preventing adhesion. Also, since the dispersibility of the hydrophobically treated particles is good, the productivity is good

It is explanatory drawing which showed typically the cross-section of the layer structure of 1st Embodiment of the cover material of this invention. It is explanatory drawing which showed typically the cross-section of the layer structure of 2nd Embodiment of the cover material of this invention. It is explanatory drawing which showed typically the layer structure of 3rd Embodiment of the cover material of this invention in the cross section. It is explanatory drawing which showed typically the layer structure of 4th Embodiment of the cover material of this invention in the cross section.

  Hereinafter, modes for carrying out the present invention will be described.

FIG. 1 is an explanatory diagram schematically showing a cross-sectional view of the layer configuration of the first embodiment of the lid member of the present invention.
In the lid 100 of the first embodiment of the present invention, the base material layer 1, the heat seal varnish layer 2, and the hydrophobic aggregated silica particle layer 3 are laminated from the outer layer side. The hydrophobic aggregated silica particle layer 3 is composed of a mixture of hydrophobic aggregated silica particles 4 and an inorganic binder 5.

FIG. 2 is an explanatory view schematically showing in cross section the layer configuration of the second embodiment of the lid of the present invention.
The lid member 200 of the second embodiment of the present invention is substantially the same as the lid member 100 of the first embodiment, but the beads 6 are added to the heat seal varnish layer 2.

FIG. 3 is an explanatory view schematically showing in cross section the layer structure of the third embodiment of the lid of the present invention.
The lid member 300 of the third embodiment of the present invention is substantially the same as the lid member 100 of the first embodiment, but the primer layer 7 is provided between the base material layer 1 and the heat seal varnish layer 2. ing.

FIG. 4 is an explanatory view schematically showing in cross section the layer structure of the fourth embodiment of the lid of the present invention.
The lid member 400 of the fourth embodiment of the present invention is substantially the same as the lid member 100 of the first embodiment, but the beads 6 are added to the heat seal varnish layer 2 to form the base material layer 1 and the heat seal varnish. A primer layer 7 is provided between the layer 2.

  The base material layer 1 of the lid member 100 is made of either paper and plastic film or a laminate of paper and plastic film. When barrier properties and the like are required, a barrier material such as an aluminum foil, an aluminum vapor deposition film, and an inorganic oxide vapor deposition film can be used as the base material layer 1 or as one layer thereof.

  Further, these papers, plastic films and the like may be laminated through an adhesive layer and an adhesive resin layer. The base material layer 1 may be printed with a product name or the like. The material, thickness, etc. of the base material layer 1 are appropriately selected depending on the suitability for processing and the required quality required.

  The paper to be used can be appropriately selected from high-quality paper, special high-quality paper, coated paper, art paper, cast-coated paper, imitation paper, craft paper, and the like. In addition, as the plastic film, a stretched or unstretched film such as polyethylene terephthalate, nylon, polypropylene, polyethylene, or a cellophane film can be appropriately selected.

  The material of the heat seal varnish used for the heat seal varnish layer 2 needs to be appropriately selected depending on the material of the container used. When the container is polystyrene, the heat seal varnish is selected from polyacrylate resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, and ethylene resin as the main component.

  When the container is polypropylene, it is selected from polyacrylate resin, ethylene-vinyl acetate copolymer resin, and modified polyolefin resin. Moreover, when a container is polyethylene, it selects from polyacrylate resin, ethylene-vinyl acetate copolymer resin, ethylene resin, and modified polyolefin resin.

The modification of the modified polyolefin is an acid modification, and is preferably an olefin modified with an unsaturated carboxylic acid or an anhydride thereof. The olefin is preferably polypropylene or polyethylene.

  Also, depending on the contents and filling method, the container is divided into chilled specifications, aseptic specifications, boil specifications, retort specifications, etc. The container material is selected according to the application and the heat seal varnish material of the lid material is selected To do. In particular, when performing high temperature sterilization such as boil specification and retort use, it is preferable to select a heat seal varnish having a softening point of 110 ° C. or higher.

  In order to obtain a structural water repellent effect called a fractal structure, beads 6 are added to the heat seal varnish layer 2 as shown in FIG. 2 of the lid material of the second embodiment and FIG. 4 of the lid material of the fourth embodiment. May be. For the beads 6, particles made of nylon, acrylic resin, styrene resin, silicone, fluororesin, and silica having an average particle diameter of 1 to 50 μm can be used.

  When the beads 6 are acrylic particles, they may be polymethyl methacrylate, polybutyl methacrylate, polyacrylate ester, polystyrene, crosslinked polymethyl methacrylate, crosslinked polybutyl methacrylate, crosslinked polyacrylate ester, or crosslinked polystyrene. preferable.

Silicone is a powder in which the surface of a spherical silicone rubber powder is coated with a silicone resin, a powder of silicone rubber having a structure in which dimethylpolysiloxane is crosslinked, or a polyorgano having a crosslinked structure represented by (RSiO _3/2 ) n. Silsesquioxane cured powder is good.

  The fluororesin is polytetrafluoroethylene polytetrafluoroethylene (PTFE), tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), fluorinated ethylene propylene tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polytetrafluoroethylene. Fluoroethylene polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene copolymer (ETFE), polytrifluorochloroethylene polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (EFEP), etc. good.

  In order to strengthen the adhesion between the base material layer 1 and the heat seal varnish layer 2, the base material is as shown in FIG. 3 of the cover material of the third embodiment and FIG. 4 of the cover material of the fourth embodiment. It is preferable to provide a primer layer 7 between the layer 1 and the heat seal varnish layer 2.

  As the primer layer 7, a resin layer is used. Resins such as ethylene-vinyl acetate copolymer resin, acrylic amine resin, polyester, urethane ester resin, vinyl acetate resin, modified olefin, imine resin, polybutadiene, ethylene-acrylic acid copolymer resin, etc. The layer 7 is preferably provided.

  The silica particles used in the hydrophobic agglomerated silica particle layer 3 can be natural silica, but silica particles produced by a wet process can be preferably used. Silica particles produced by a wet process form aggregates, and the average particle size of the aggregates of the silica particles is preferably 0.1 to 10 μm. More preferably, it is 1-5 micrometers. The aggregate of silica particles is used after being hydrophobically treated.

  The wet production methods are roughly classified into a precipitation method and a gel method, and any of these production methods may be used. Aggregates of silica particles produced by a wet manufacturing method are characterized by tightly agglomerating bonds between silica particles, and the variation in average particle size is larger than that of the dry method, and the particle sizes vary widely. By being present, a structural water repellency called a fractal structure is formed.

  The average particle size here refers to the particle size in a state where silica is agglomerated, and can be measured by the Coulter method, the dynamic scattering method, or the laser scattering method. Use the diameter. Productivity improves by making an average particle diameter into 0.1-10 micrometers, Preferably it is 1-5 micrometers. If it is less than 0.1 μm, it is difficult to disperse and is easily gelled, and if it exceeds 10 μm, it is likely to precipitate and the productivity is remarkably lowered.

  The hydrophobic treatment on the surface of the aggregate of silica particles can be performed by a method of coating a silane coupling agent, a CVD method, or a plasma method. Hydrophobic treatment of the surface with dimethylpolysiloxane and dimethylsiloxane. Alternatively, if the functional group obtained on the surface by hydrophobic treatment is any of dimethylsilyl, trimethylsilyl, aminoalkylsilyl, alkylsilyl, and methacrylsilyl, the treatment method need not be specified. By generating these functional groups, water repellency is improved by reducing the critical surface tension (surface energy).

  The DBA value of the hydrophobic aggregated silica particles 4 obtained by subjecting the aggregates of silica particles to hydrophobic treatment is preferably 50 mmol / kg or less, more preferably 20 mmol / kg or less. Thus, if DBA value is low, there will be few residual silanol groups after hydrophobic treatment, and it will be easy to obtain high water repellency.

  The DBA value (mmol / Kg) represents the degree of hydrophobicity of the hydrophobically treated particles. The DBA value is the number of mmols of dibutylamine required to neutralize 1 kg of hydrophobically treated particles such as silica. The silanol groups on the surface of hydrophobically treated particles easily react with dibutylamine. Can be measured.

  In the hydrophobic treatment, the surface of the aggregate of silica particles may be treated, and the inside of the aggregate may be hydrophilic. That is, the individual primary particles inside the aggregate that are not present on the surface of the aggregate may be hydrophilic without the surface being subjected to a hydrophobic treatment.

  Further, a small amount of small dry silica having an average particle size of 1 μm or less may be added to the hydrophobic aggregated silica particles 4 in order to form large and small fractal structural water repellent layers. Furthermore, beads 6 made of nylon, acrylic, styrene, silicone, silica, or fluorine having an average particle diameter of 1 to 50 μm may be added.

  When the hydrophobic agglomerated silica particles 4 are strongly adhered to the heat seal varnish layer 2, it is desirable to mix the hydrophobic particles with the inorganic binder 5 and apply it. More preferably, a silica compound prepared by a sol-gel method is used as a binder.

The inorganic binder 5 by the sol-gel method is made from either a metal alkoxide, a hydrolyzate of metal alkoxide, or a composite thereof. The metal alkoxide is a general formula M (OR) n (M is Si, Ti, Al, etc.) such as tetraethylorthosilicate (Si (OC ₂ H ₅ ) ₄ ), triisopropylaluminum (Al (OC ₃ H ₇ ) ₃ ). A metal such as Zr, and R is an alkyl group such as CH ₃ or C ₂ H ₅ . Among them, the characteristics of metal alkoxides in which M is Si, Al, or Ti are good.

  The blending ratio of the hydrophobic agglomerated silica particles 4 and the inorganic binder 5 and the film thickness to be applied are adjusted by the close contact with the substrate to be applied and the repellency (water repellency) of the content to be obtained. As a coating method, a roll coating method, a spin coating method, a dipping coating, a gravure coating method, a spray coating method, a comma coating method, or the like can be used.

In the hydrophobic agglomerated silica particle layer 3, the hydrophobic agglomerated silica particles 4 are randomly formed from an inorganic binder 5.
The film is formed as a lump existing on the surface. Since the hydrophobic agglomerated silica particles 4 are mixed with the inorganic binder 5 to form a coating film, the hydrophobic agglomerated silica particles 4 are vitrified and become harder than the heat seal varnish layer 2 of the organic compound or the container of the organic compound.

  Moreover, since the adhesiveness with the heat seal varnish layer 2 is strong, since the expansion and contraction of the hydrophobic agglomerated silica particle layer 3 is small in the thermocompression-bonded seal part, this layer is randomly partially cracked. Since the adhesion between the heat seal varnish layer 2 and the hydrophobic agglomerated silica particle layer 3 is strong, the resin of the container or the resin of the heat seal varnish layer 2 enters the cracked portion. A strong seal is maintained by melting the container and the heat seal varnish by the resin that has entered.

  Specific examples of the present invention will be described below.

<Example 1>
An aluminum foil of 7 μm was laminated on a biaxially stretched nylon film of 15 μm by dry lamination. As the adhesive, an isocyanate curing agent was blended into the main aliphatic ester, and the coating amount (after drying, the same applies hereinafter) was 3 g / m ² . Next, the same adhesive was applied to the aluminum foil surface at a coating amount of 3 g / m ² , and a biaxially stretched polyethylene terephthalate film 12 μm was laminated by dry lamination to prepare a base material layer 1.

On the surface of the biaxially stretched polyethylene terephthalate film of the base material layer 1, an isocyanate curing agent is blended with the main polyester resin, applied by a bar coating method, dried at 80 ° C. for 1 minute, and applied in an amount of 1 g / m. ^Two primer layers 7 were provided.

On the surface of the primer layer 7, as a heat seal varnish layer 2, a heat seal varnish obtained by adding polymethacrylic resin having an average particle diameter of 20 μm of beads 6 to a polyacrylate resin as a main component so that the weight ratio becomes 1/1 is a bar. The coating was performed by a coating method, and the coating amount was 3 g / m ² .

  The surface of the agglomerated silica particles having an average particle diameter of 2.5 μm produced by the wet production method was subjected to hydrophobic treatment with dimethylpolysiloxane by the Coulter method to produce hydrophobic agglomerated silica particles 4 having a DBA value of 10 mmol / Kg. This was adjusted to 10 wt% solids with methanol.

Separately, tetraethylorthosilicate (Si (OC ₂ H ₅ ) ₄ ) is hydrolyzed, water is added to adjust the solid content in terms of SiO ₂ to 10 wt%, and the solution for inorganic binder 5 Adjusted.

The methanol-adjusted liquid of the hydrophobic aggregated silica particles 4 and the solution for the binder 5 are mixed at a weight ratio of 1: 1 to prepare a coating solution for the hydrophobic aggregated silica particle layer. The surface was coated by a bar coating method to provide a hydrophobic aggregated silica particle layer 3 having a coating amount of 2 g / m ² .

  The lid material of Example 1 was created as described above. Further, the lid material of Example 1 was thermocompression bonded to the flange portion of the polystyrene container.

<Example 2>
A lid material of Example 2 was prepared in the same manner as the lid material of Example 1 except that a heat seal varnish whose main component to which beads 6 were not added was used as the heat seal varnish layer 2 was a polyacrylate resin. Further, the lid material of Example 2 was similarly heat-pressed to the flange portion of the polystyrene container.

<Example 3>
Example 1 except that a heat seal varnish in which a polymethacrylic resin of beads 6 was added to a main component ethylene-vinyl acetate copolymer resin so that the weight ratio was 1/1 was used as the heat seal varnish layer 2. The lid material of Example 2 was created in the same manner as the lid material of No. 2. The lid material of Example 2 was similarly heat-pressed to the flange portion of a polypropylene container.

<Example 4>
A hydrophobic agglomerated silica particle layer having a coating amount of 2 g / m ² is prepared by using trimethylsilyl as a functional group on the surface of the agglomerated silica particles by using a Coulter method, and preparing and using hydrophobic agglomerated silica particles 4 having a DBA value of 10 mmol / Kg. A lid material of Example 4 was prepared in the same manner as the lid material of Example 1 except that 3 was provided. Further, the lid material of Example 4 was thermocompression bonded to a flange portion of a polypropylene container.

<Example 5>
The lid of Example 5 was prepared in the same manner as in Example 1 except that the hydrophobic agglomerated silica particle layer 3 was provided using agglomerated silica particles having an average particle diameter of 1.0 μm produced by a wet process. Created. Further, the lid material of Example 5 was thermocompression bonded to a flange portion of a polyethylene container.

<Example 6>
The lid of Example 6 was prepared in the same manner as in Example 1 except that the hydrophobic agglomerated silica particle layer 3 was provided using agglomerated silica particles having an average particle diameter of 5.0 μm produced by a wet process. Created. Further, the lid material of Example 6 was thermocompression bonded to a flange portion of a polyethylene container.

  Below, the comparative example of this invention is demonstrated.

<Comparative Example 1>
Instead of using the agglomerated silica particles having an average particle diameter of 1.0 μm produced by the wet manufacturing method, the same procedure as in Example 1 was performed except that the dry method silica having an average particle diameter of 0.01 μm by the dry method was used. Thus, a lid material of Comparative Example 1 was prepared. Further, the lid material of Comparative Example 1 was thermocompression bonded to a flange portion of a polyethylene container.

<Comparative example 2>
The lid material of Comparative Example 2 was prepared in the same manner as in Example 1 except that the hydrophobic agglomerated silica particle layer 3 was provided using agglomerated silica particles having an average particle diameter of 15.0 μm produced by a wet process. Created. The lid material of Comparative Example 2 was thermocompression bonded to a flange portion of a polyethylene container.

<Comparative Example 3>
The agglomerated silica particles 4 having a DBA value of 500 mmol / Kg are used on the surface of the agglomerated silica particles having an average particle diameter of 2.5 μm manufactured by a wet process, and the coating amount is 2 g / m. A cover material of Comparative Example 3 was prepared in the same manner as in Example 1 except that ² agglomerated silica particle layers were provided. The lid material of Comparative Example 3 was thermocompression bonded to the flange portion of a polyethylene container.

<Comparative example 4>
Methanol adjustment of hydrophobic agglomerated silica particles 4 using dry method silica having an average particle size of 0.01 μm by a dry method instead of using agglomerated silica particles having an average particle size of 1.0 μm produced by a wet process A lid material of Comparative Example 4 was prepared in the same manner as in Example 1 except that the liquid was used and the hydrophobic aggregated silica particle layer 3 was provided without using the solution for the binder 5. Further, the lid material of Comparative Example 4 was thermocompression bonded to a flange portion of a polyethylene container.

<Test method>
The methanol adjustment liquid, the lid material, and the container in which the lid material was thermocompression-bonded in the production of the lid material of the example and the comparative example were tested by the following methods and subjected to comparative evaluation.

<Coating fluid stability>
The coating liquid for hydrophobic agglomerated silica particle layer was allowed to stand for 3 hours, and its stability was evaluated.
A coating solution that deteriorated due to gelation or precipitation was rated as x, and the others were marked as ◯. The results are summarized in Table 1.

<Repellent>
Water and yoghurt (plain sugar-free) were dropped onto the surface of the water-repellent layer 3 of the lids of Examples and Comparative Examples, and their repellent properties were evaluated. The evaluation was made with a repellent cover material as ◯ and a non-repeltable cover material as ×, and the results are summarized in Table 1.

<Sealability>
The sealing strength of the container obtained by thermocompression bonding of the lid material of the example and the comparative example was evaluated before retort sterilization and after retort sterilization, respectively, and the water repellent layer 3 of the peeled portion (thermocompression bonded portion). Checked the position.

  The heat sealing conditions for thermocompression bonding were heat sealing at a temperature of 210 ° C. with a seal bar pressing of 3 kgf and a sealing time of 2.0 sec. Moreover, retort sterilization was performed at 100 ° C. for 30 minutes.

  The seal strength was sufficient, and the peeled portion (thermocompression bonding portion) where the position of the water repellent layer 3 was on the container side was evaluated as ◯, and the others were evaluated as ×. The results are summarized in Table 1.

以下に、実施例と比較例との比較結果について説明する。

Below, the comparison result of an Example and a comparative example is demonstrated.

<Comparison result>
The lid materials of Examples 1 to 6 have good stability of the coating liquid for the hydrophobic agglomerated silica particle layer, and the surface of the hydrophobic agglomerated silica particle layer 3 has a repelling property against water and yogurt. All were good, and the sealing performance without retort sterilization was also good. In Example 3, since the heat seal varnish layer 2 is mainly composed of an ethylene-vinyl acetate copolymer resin, the sealing performance does not deteriorate even after retort sterilization at 100 ° C. for 30 minutes. It was.

  On the other hand, Comparative Examples 1 and 2 had good repellent properties against the water and yogurt on the surface of the hydrophobic agglomerated silica particle layer 3, and also had good sealing performance without retort sterilization. However, the coating liquid for hydrophobic agglomerated silica particle layer was not stable and gelled or precipitated.

  The cover material of Comparative Example 3 also has coating solution stability and good sealability before retort sterilization, but the repelling property, which is an essential object of the present invention, was poor in both water and yogurt. .

  The lid material of Comparative Example 4 had good repelling properties for water and yogurt on the surface of the hydrophobic agglomerated silica particle layer 3 but was poor in sealing properties before retort sterilization. The stability of the coating solution was also poor.

DESCRIPTION OF SYMBOLS 100, 200, 300, 400 ... Cover material 1 ... Base material layer 2 ... Heat seal varnish layer 3 ... Hydrophobic aggregation silica particle layer 4 ... Hydrophobic aggregation silica particle 5 ... Inorganic binder 6 ... Bead 7 ... Primer layer

Claims (10)

A base material layer, a heat seal varnish layer, and a hydrophobic agglomerated silica particle layer are sequentially laminated, and the hydrophobic agglomerated silica particle layer is formed on the surface of agglomerated silica particles having an average particle size of 0.1 to 10 μm. It consists of hydrophobic agglomerated silica particles that have been hydrophobically treated,
The lid material , wherein the hydrophobic aggregated silica particle layer is composed of a mixture of the hydrophobic aggregated silica particles and an inorganic binder .   The surface of the aggregate is hydrophobically treated with dimethylpolysiloxane or dimethylsiloxane, or is hydrophobically treated with any functional group of dimethylsilyl, trimethylsilyl, aminoalkylsilyl, alkylsilyl, or methacrylsilyl. The lid according to claim 1.   The lid material according to claim 1 or 2, wherein the aggregate of silica particles is manufactured by a wet manufacturing method.   The lid material according to any one of claims 1 to 3, wherein the hydrophobic aggregated silica particles have a DBA value of 50 mmol / Kg or less. The inorganic binder comprises a metal alkoxide represented by M (OR) n or a hydrolyzate of metal alkoxide, the metal (M) is Si, Al, Ti, R is an alkyl group, and n is The lid material according to any one of claims 1 to 4, wherein the lid material is a valence of a metal (M). The beads according to any one of claims 1 to 5, wherein beads comprising any one of nylon, acrylic resin, styrene resin, silicone, fluororesin, and silica having an average particle diameter of 1 to 50 µm are added to the heat seal varnish layer. The lid material according to claim 1 . The acrylic resin beads are any one of polymethyl methacrylate, polybutyl methacrylate, polyacrylate ester, polystyrene, crosslinked polymethyl methacrylate, crosslinked polybutyl methacrylate, crosslinked polyacrylate ester, and crosslinked polystyrene. The lid member according to claim 6 . A primer layer is provided between the base material layer and the heat seal varnish layer, and the primer layer is made of ethylene-vinyl acetate copolymer resin, acrylic resin, ester resin, vinyl chloride resin, modified olefin resin, imine. The lid material according to any one of claims 1 to 7, wherein the lid material is made of a resin, a polybutadiene resin, or an ethylene-acrylic acid copolymer resin. The lid material according to any one of claims 1 to 8, wherein the lid material has a softening point of the heat seal varnish of the heat seal varnish layer of 110 ° C or higher. The lid material is a container lid material, and the hydrophobic aggregated silica particle layer is broken by sealing to the seal portion of the container, and the heat seal varnish of the heat seal varnish layer and the seal portion of the container The lid material according to any one of claims 1 to 9, wherein the lid material is melt-bonded.

Images