JPH0232965A - Heat sealable lid material for use on seal packaging container - Google Patents

Abstract

PURPOSE:To contrive the improvement of a seal packaging container under an easy-to-open condition by rendering silane monomer present on an opening of a seal packaging container and its surfaces to be heat sealed. CONSTITUTION:A heat sealable layer 2 containing silane monomer is provided on the one side of an aluminum foil 1 with an adhesive layer 3 interposed therebetween, whereby the silane monomer is made present on an opening 10 of a seal packaging container such as glass container and the surface to be heat sealed. An anticorrosion coating layer 4 is provided on the other side of the aluminum foil 1. The heat sealable layer 2 is arranged through the adhesive layer 3 on one side of the aluminum foil. The heat sealable layer 2 has on its surface a coating layer 5 containing the silane monomer, whereby the silane monomer is made present on the opening 10 of the glass container and the surface to be heat sealed. The anticorrosion coating layer 4 is similarly formed on the other side of the aluminum foil 1.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a heat-sealable lid material for a sealed packaging container.

Conventional technology Conventionally, in order to hermetically package powdered, liquid, or viscous foods in glass containers such as bottles, a metal cap is caulked to the mouth of the container after the food is filled, or a metal or synthetic resin cap is used. It was sealed by screwing on a screw cap or by putting a crown on it. Conventionally, a lid material has been coated with a thermoadhesive resin, and this lid material has been bonded to the mouth of a glass container by heat sealing.

Problems to be Solved by the Invention However, the above-mentioned caps and crowns have problems in that they are relatively difficult to open and are expensive. In addition, when heat-sealing the heat-adhesive resin coated on the lid to the mouth of a glass container, if the contents of the container are powder such as powdered milk or instant coffee, there is a gap between the mouth of the container and the lid. Although there is no decrease in the adhesive strength of the adhesive part, if the contents are viscous, such as alcohol, juice, or jam, the heat-sealing adhesive between the container opening and the lid may be removed during storage. If water enters the area, the adhesion strength will decrease significantly.
In severe cases, there was a problem in that the lid material would peel off.

In particular, when directly thermally bonding a lid to the mouth of a glass container, the surface of the mouth of the glass container is porous;
Due to its relatively weak polarity and poor adhesion, it has recently been developed to use a carboxyl-modified saponified ethylene-vinyl acetate copolymer with improved adhesion as a heat-adhesive resin for lid materials. (For example, JP-A-60-17804
(See Publication No. 2). Such thermoadhesive resins certainly have excellent thermal adhesion properties in a very short period of time and at relatively low temperatures, and also have a moderate adhesive strength that satisfies the requirements for easy opening. However, if water enters the bonded area after heat sealing, there is a problem in that the adhesion is significantly reduced and the lid material is easily peeled off from the bonded interface.

By the way, it has already been known to directly coat the mouth of a glass container with a silane coupling agent as a sealing material (for example, see Japanese Patent Publication No. 8273/1983). The work of coating the sealant is extremely troublesome, and the surface of the opening of the glass container is porous and uneven, making it difficult to apply the sealant uniformly. Therefore, if the amount of sealing material applied is not sufficient, it will be difficult to achieve a uniform seal due to the unevenness of the opening, variations in parallelism, etc., and if the amount applied is too large,
There was a problem of high cost.

Furthermore, a method is already known in which a metal salt, a silane coupling agent, etc. are used as an anchor coat layer on the opening of a glass container, and this layer is further coated with a thermoadhesive resin (for example, Japanese Patent Publication No. 81-9181) However, with this conventional method, when the container is opened, some of the resin from the lid material may remain at the mouth of the container, damaging the appearance, and the mouth of the container must be coated with thermoplastic resin in advance. Therefore, the number of steps increases accordingly,
There were problems in that the productivity of the container was poor and the cost was high.

Furthermore, conventionally, heat-sealable lidding materials (for example, JP-A-80-58
549 Publication), and a heat sealing lid material comprising a heat sealing material layer made of an ionomer composition containing a silane coupling agent applied to one side of a metal foil through an ionomer layer is already known (see Japanese Patent Publication No. 549). For example, JP-A-61-104
(See Publication No. 971). Such silane coupling agents have the effect of chemically bonding inorganic materials and organic materials, but their chemical bonding effect is not very strong, so they have poor water resistance and are not easily water resistant. There was a problem in that the adhesive strength decreased under environmental conditions.

As a result of intensive research to solve the above-mentioned problems of the conventional technology, the inventors found that the adhesiveness of the heat sealing material was improved by using a silane monomer that has more polar groups than the silane coupling agent. They discovered that the adhesive strength was further improved and completed this invention.

The object of this invention is to provide a material that has excellent adhesion even to porous and relatively weakly polar surfaces such as the mouth of glass containers, and can seal and package lids in a short time. Not only can it be heat-sealed to the mouth of a container, but it also ensures that water does not enter the heat-sealed area even when the contents of the container are liquid or viscous, such as alcohol, juice, or jam. The water resistance of the heat-sealed bonded part is greatly increased, the adhesive force decreases less in a water environment, and a good adhesive state can be maintained for a long period of time. An object of the present invention is to provide a heat-sealable lid material for a sealed packaging container, which improves sealing performance.

Means for Solving the Problems In order to achieve the above object, the heat-sealing lid material for a hermetically sealed packaging container according to the present invention has a silane monomer present on the surface to be thermally bonded to the mouth of the hermetically sealed packaging container. It is a special feature that is characterized by being

Here, there are two ways to make the silane monomer exist on the surface of the lid material to be thermally bonded.

(1) First of all, by providing a heat sealing material layer containing silane monomer on one side of the metal foil as the base material of the lid material, the surface to be thermally bonded to the mouth of the sealed packaging container is
If silane monomer is allowed to be present.

(■) Second, a heat sealing material layer is provided on one side of the metal foil, and the surface of this heat sealing material layer is coated with silane monomer, so that it can be thermally bonded to the mouth of the sealed packaging container. When silane monomer is present on the surface.

In the above, the metal foil that is the base material of the lid material is usually aluminum foil, but other metal foils may be used. In the case of aluminum foil, its thickness is 5-2007m
, preferably 20 to 80 fakes.

As the heat sealing material, any commonly used heat sealing material can be used.

Specifically, as a heat sealing material, polyethylene, a copolymer of ethylene and vinyl acetate, a copolymer of ethylene and an unsaturated carboxylic acid, or a saponified product of an ethylene-vinyl acetate copolymer and a carboxyl group-containing inorganic material are used. Modified products obtained by graft polymerization of saturated compounds, ionomers, water-dispersed polyolefins, mixtures of water-dispersed polyolefins and water-soluble epoxy resins, polyesters, modified polypropylene, polyvinyl chloride, polyvinyl butyral, polymethacrylic esters, and polyacrylic acids At least one thermoplastic synthetic resin selected from the group consisting of esters is used.

Among these resins, ethylene-vinyl acetate and ethylene-vinyl acetate have excellent thermal adhesion properties in a short time and at relatively low temperatures to the porous and relatively weakly polar mouth surface of glass containers. Modified products obtained by graft polymerizing a carboxyl group-containing unsaturated compound to a saponified polymer (see, for example, JP-A-80-178042), and ionomers (see, for example, JP-A-81-54587).
It is preferable to use

Here, the former carboxyl modified product of saponified ethylene-vinyl acetate copolymer is, for example, as follows.

That is, melt index 1-300g/10
(according to ASTM 123B-65T) and an ethylene content of 50 to 97 ffi ffi%, preferably 60 to 82% by weight, is saponified to produce a copolymer with a hydroxyl equivalent of 100 to 100%. 3000g
/ 1 equivalent, preferably 200 to 1000 g / 1 equivalent, and then graft polymerization of a carboxylic acid group-containing unsaturated compound to this saponified product.

Here, examples of the carboxylic acid group-containing unsaturated compound include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, maleic anhydride, and citraconic acid. The resulting graft polymer, namely ethylene-
The carboxyl modified product of saponified vinyl acetate copolymer is
The overall acid equivalent is 50,000 g/1 equivalent or less, preferably 1,000 to 30,000 g/1 equivalent.

The latter ionomer is composed of a monoolefin-unsaturated carboxylic acid copolymer resin or a metal salt thereof.

Here, the monoolefin-unsaturated carboxylic acid copolymer resin includes an α-monoolefin such as ethylene, propylene, 1-butene, isobutyne, 4-methyl-1-pentene, 1-hexene, and 1-heptene; α such as acrylic acid, methacrylic acid, methacrylic acid, crotonic acid,
It is based on a resin obtained by copolymerizing β-unsaturated carboxylic acid, and typical examples include ethylene-acrylic acid copolymer resin and ethylene-methacrylic acid copolymer resin. It will be done. The molecular weight of such a copolymer resin is 1,000 to 200,000, and the unsaturated carboxylic acid content in the copolymer resin is 1 to 30% by weight, preferably 2 to 20% by weight.

Examples of metal salts of monoolefin-unsaturated carboxylic acid copolymer resins include alkali metal ions such as sodium and potassium, or alkaline earth salts such as zinc, magnesium, and calcium. Examples include ionically crosslinked resins, ie, ionomer resins, obtained by neutralization with similar metal ions. The degree of neutralization by metal ions is, for example, 0.5 to 40%. In particular, it is preferable to use an ionomer resin made of a zinc salt of an ethylene-methacrylic acid copolymer resin. The carboxylic acid content of the ionomer resin is 5 to 18%, and the degree of ionization is several % to 90%.

In addition, the above-mentioned silane monomer has a general chemical structural formula,
The one represented by R81X3 is used.

In the formula, R represents an alkyl group, and X represents a hydrolyzable group bonded to a silicon atom, such as chlorine, an alkoxy group, or an acetoxy group.

Specific examples of silane monomers include triethoxymethylsilane, trimethoxymethylsilane, triethoxyphenylsilane, trimethoxyphenylsilane, and the like.

As the silane monomer, two or more of these compounds may be mixed.

The thickness of the heat sealing material layer is usually 5 to 300/1177
'.

Preferably 20-100j! It is 1N.

When a heat sealing material layer containing a silane monomer is provided on one side of the metal foil of the lid material in (I) above, so that the silane monomer is present on the surface to be thermally bonded to the mouth of the sealed packaging container. The content of the silane monomer in the heat sealant layer is 0.05 to 20% by weight, preferably 0.05% to 20% by weight.
The amount is 1 to 5% by weight.

Furthermore, a heat sealing material layer is provided on one side of the metal foil of the lid material in (n) above, and by coating the surface of this heat sealing material layer with silane monomer, it can be thermally bonded to the mouth of the sealed packaging container. When the silane monomer is present on the surface to be treated, the thickness of the silane monomer coating layer is 0.
．． 01 to 50, preferably 0.1 to IO-.

In cases (I) and (II) above, when the content of the silane monomer is less than 0.05% by weight and when the thickness of the coating layer of the silane monomer is less than 0.01/m, the silane monomer If the amount is too small, the active chemical bonding effect of the silane monomer will not be sufficiently exerted, the water resistance of the heat-sealed joint will be poor, and the adhesive strength will decrease in a water environment, which is not preferable.

Conversely, when the content of silane monomer exceeds 20% by weight, or when the thickness of the silane monomer coating layer exceeds 50p, not only will the adhesive strength in a water environment not change much, but the cost will increase. Undesirable.

In addition, when a heat sealing material layer containing a silane monomer is provided on one side of the metal foil of the lid material in (1) above, the silane monomer bleeds onto the surface of the heat sealing material layer and is diffused to the surface side and becomes concentrated. The state will be as follows. In this case, the silane monomer is preferably present in an amount of 1% or more on the surface to be heat-sealed at the mouth of the sealed packaging container, that is, on the surface of the heat-sealing material layer. .

In addition, when coating a silane monomer on the surface of the heat sealing material layer provided on one side of the metal foil of the lid material in (II) above, the silane monomer is coated on the surface to be thermally bonded to the mouth of the sealed packaging container. is made to exist 100%,
Therefore, it is important to adjust the thickness of the coating layer, that is, the amount of silane monomer present on the surface to be heat sealed.
This is easier than case I).

In some cases, a required amount of a silane coupling agent such as mercaptosilane, aminosilane, epoxysilane, vinylsilane, and methacrylsilane, or a titanium coupling agent and an aluminum coupling agent may be added to the silane monomer. .

Further, the heat sealing material layer is preferably filled with an inorganic compound in order to ensure low-temperature sealability and to prevent blocking during punching by press.

Here, examples of inorganic compounds include oxides, hydroxides, carbonates, and sulfates of magnesium, calcium, aluminum, titanium, and silicon, talc, clay, feldspar powder, mica, pallite, etc., and particularly preferred. Calcium carbonate, talc is used.

The average particle size of these inorganic compounds is 0.1 to 50p, preferably 0.5 to 30p, and the inorganic compound is added in an amount of 30 parts by weight or less, usually 0.1 to 100 parts by weight of the thermoadhesive resin.
．． 1 to 20 parts by weight, preferably 1 to IO parts by weight are mixed.

The above-mentioned heat-adhesive resin and inorganic compound are mixed using, for example, a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneader, etc., usually at a temperature of 15 to 200°C.

In order to provide a heat sealing material layer on one side of the metal foil, a heat sealing material containing or not containing a silane monomer as described above is processed into a film in advance, and this film is coated on one side of the metal foil with a layer of, for example, polyester isocyanate. They may be bonded through an adhesive such as a two-component reactive adhesive, or they may be bonded directly by extruding a melted heat sealing material onto one side of the metal foil using an extruder. .

Further, when coating the surface of the heat sealing material layer with a silane monomer, it may be carried out, for example, by a spray method, a brush coating method, a roll coating method, or the like.

Note that, if necessary, a resin film such as polyethylene or polypropylene may be interposed between the heat sealing material layer and the metal foil. This improves cushioning properties during heat sealing and prevents corrosion of the metal foil due to contents such as dressing and mustard.

Note that the other side of the metal foil is usually subjected to necessary printing, and furthermore, an anticorrosive coating layer is provided on this surface. A lid made of metal foil and a heat sealant layer is continuously punched and formed into a shape and size that covers the mouth of a glass container.

The hermetically sealed packaging container sealed by the heat-sealable lid according to the present invention is made of, for example, glass, metal, ceramic, or earthenware.

1 to 3 show specific examples of the lid material according to the present invention. First, the lid material shown in Fig. 1 consists of a heat sealing material layer (2
) is provided through the adhesive layer (3), so that the silane monomer is present on the surface to be thermally bonded to the mouth (10) of a sealed packaging container such as a glass container. An anticorrosive coating layer (4) is applied to the other side of the aluminum foil (1).

In addition, the lid material shown in Fig. 2 has a heat sealing material layer (2) provided on one side of an aluminum foil (1) via an adhesive layer (3), and a heat sealing material layer (2) is provided on the surface of this heat sealing material layer (2). By applying the silane monomer coating layer (5), the silane monomer is present on the surface to be thermally bonded to the opening (lO) of the glass container. Aluminum foil (1
) is similarly coated with an anti-corrosion coating layer (4).

Furthermore, the lid material shown in FIG. 3 has almost the same structure as the lid material shown in FIG. A heat sealing material layer (2) containing a silane monomer is provided on this intermediate layer (7) via an adhesive layer (3), and a heat sealing material layer (2) containing a silane monomer is provided in addition to the aluminum foil (1). A printed layer (6) is provided on the surface, and an anticorrosive coating layer (4) is further provided on the surface.

According to the heat-sealing lid material of the present invention, a silane monomer is present on the surface to be thermally bonded to the opening (10) of the hermetically sealed packaging container. By using a monomer, the adhesiveness of the heat-sealing lid material is improved and the adhesiveness is further improved, so there is little decrease in adhesive strength in a water environment and a good adhesive state can be maintained for a long period of time. This is thought to be due to the following reasons.

That is, for example, heat sealing materials applied to lids of glass containers contain -OH groups and resins containing a large number of functional groups, such as carboxyl modified products of saponified ethylene-vinyl acetate copolymers in which 10H or -COOH groups have been introduced into monoolefins,
and ionomer resins are used to improve adhesion, but even when such resins are used, the heat sealing process time is very short, so the functional groups in the heat sealing resin are not bonded to the glass. It is thought that the resin does not interact with the glass component on the upper surface of the mouth of the container to form hydrogen bonds, but instead adheres to the glass surface mainly due to van der Waals forces. In particular, immediately after heat sealing, the molecular segments of the heat sealing resin undergo thermal movement and their orientation is disordered, making it difficult for hydrogen bonds to occur and adhesion is primarily due to van der Waals forces. After heat sealing, the functional groups are gradually arranged on the glass surface over time, form hydrogen bonds with the silanol groups on the glass surface, and the adhesive strength gradually increases.

However, when the contents of a glass container are liquid or viscous, the glass surface at the container mouth is hydrophilic, so water molecules tend to get wet, forming a multi-molecular layer of water molecules, which makes heat sealing difficult. The van der Waals forces at the bond are weakened and the hydrogen bonds are also broken, resulting in a significant decrease in adhesive strength.

On the other hand, according to the heat-sealing lid material of the present invention, a silane monomer is present on the surface to be thermally bonded to the opening of the glass container, and such silane monomer contains many polar groups and therefore Since the number of functional groups per unit volume of light is large, it generally has a more active chemical bonding effect than a silane coupling agent, and it chemically bonds the resin component in the heat sealing material layer with the inorganic filler. In addition, during heat sealing, the silane monomer present on the surface of the heat sealing material firmly bonds to the glass surface, making the adhesive strength between the heat sealing material of the lid material and the opening surface of the glass container extremely strong. Therefore, it is possible to reliably prevent water from entering the adhesive interface, and the water resistance of the heat-sealed adhesive portion is greatly increased.

Example Next, examples of the present invention will be described together with comparative examples.

Example 1 As shown in Fig. 1, various amounts of silane monomer (trade name A163, Nippon Unicar Co., Ltd. A heat sealing material layer 2) consisting of a heat sealing material film with a thickness of 50 mm mixed with a heat sealant film (manufactured by a company) was bonded via an adhesive layer (3) to make various lid materials (sample nos. 1 to 5). Ta. Here, the heat sealing material is a modified product obtained by graft polymerizing acrylic acid to a saponified product of ethylene-vinyl acetate copolymer (registered trademark Dumilan, manufactured by Takeda Pharmaceutical Company Limited), with an average particle size of Approximately 1 rhino calcium carbonate 5
A uniformly dispersed mixture of % by weight was used.

The various lid materials thus obtained were punched out using a punching press into a predetermined shape and size corresponding to the opening (10) of a glass container.

Next, the glass container was filled with water at 40°C, and the lid material was placed at the mouth of the container at a temperature of 200°C and a pressure of 160 kgf.
The lids were heated and pressurized for 2 seconds under the conditions of 1/2 lbs., and these lids were directly bonded to the mouth (10) of the glass container by heat sealing to seal the container.

Then, for these sealed containers, the peel strength of the lid material immediately after heat sealing and the peel strength of the lid material after the sealed glass container was left upside down at 40°C for 30 days were measured, and the results were obtained. are shown in the table below.

Example 2 In this example, as shown in Figure 2, the same heat sealing material layer (2) as in Example 1 was applied on one side of the aluminum foil (1) via an adhesive layer (3). After dry lamination, a solution of silane monomer (Product Meijin 163, manufactured by Nippon Unicar Co., Ltd.) diluted in a solvent in advance is applied to the surface of the heat sealing material layer (2) and dried at 130°C for 5 minutes. , a coating layer (5) of silane monomer having various thicknesses was formed, and a lid material (sample Nα6) was formed.
~10) were created.

Example 3 In this example, as shown in FIG. 2, the same heat sealing material layer (2) as in Example 1 was applied on one side of the aluminum foil (1) via an adhesive layer (3). After dry laminating, a solution of silane monomer (trade name A162, manufactured by Nippon Unicar Co., Ltd.) diluted in a solvent in advance is applied to the surface of the heat sealing material layer (2) and dried at 130°C for 5 minutes. A coating layer (5) of silane monomer having a thickness of 0.5 mm was formed to produce a lid material (sample N (Lll)).

Example 4 In this example, as shown in Figure 2, a special ionomer, namely a monoolefin-unsaturated carboxylic acid copolymer resin, was applied to one side of an aluminum foil (1) via an adhesive layer (3). Metal salt, trade name “Himilan 1702J”
(manufactured by DuPont DuPont Polychemical Co., Ltd., melt index 14 g/10 minutes, zinc ion type) A heat sealing material layer (2) with a thickness of 50 p was provided by dry lamination, and then a silane monomer layer (2) diluted in a solvent in advance ( A coating layer (5) of silane monomer with a thickness of about 0.5p is formed by applying a solution of product name A163 (manufactured by Nippon Unicar Co., Ltd.) on the surface of the heat sealing material layer (2) by a roll coating method. and lid material (sample No. 12)
I made it.

Lid materials obtained in Examples 2 to 4 above (sample No. 8 to +
Regarding 2), a sealed packaging test was conducted in the same manner as in Example 1, and the obtained results are shown in the table below.

Comparative Example 1 For comparison, 5% by weight was applied to one side of the aluminum foil (1) via the adhesive layer (3) in the same manner as in Example 1 above.
A heat sealing material layer (2) made of a heat sealing material film with a thickness of 50 mm mixed with a silane coupling agent (trade name A-187, manufactured by Nippon Unicar Co., Ltd.) is bonded via an adhesive layer (3). Then, I made the lid material.

Comparative Example 2 For comparison, a heat sealing material layer (2), which is the same as in Example 1 above but does not contain silane monomer, was dried through an adhesive layer (3) on one side of the aluminum foil (1). It was installed by laminating.

A sealed packaging test was conducted on the lid materials obtained in Comparative Example 1 and Comparative Example 2 in the same manner as in Example 1, and the results are shown in the table below.

(Hereinafter, blank space) As is clear from the above table, according to the lid material of the present invention,
Since the silane monomer is present on the surface to be thermally bonded to the mouth (10) of the glass container, the strong chemical bonding action of the silane monomer greatly increases the adhesion to the surface of the mouth of the glass container. Even after a glass container filled with water is stored upside down for a long time, the adhesive strength of the lid material does not decrease, and the water resistance is good and the sealing performance is excellent.

On the other hand, the lid material of Comparative Example 1 using a silane coupling agent was inferior in both adhesiveness and water resistance compared to the lid material of the example using a silane monomer. Further, according to the lid material of Comparative Example 2 using a heat sealing material that does not contain silane monomer, the lid material peeled off when the glass container was stored upside down for a long time, and the water resistance was poor.

Effects of the Invention As mentioned above, the heat-sealing lid material according to the present invention has silane monomer present on the surface to be thermally bonded to the mouth of the sealed packaging container. Due to the bonding action, the resin component in the heat sealing material layer and the inorganic filler such as calcium carbonate and talc contained in the heat sealing material are not only chemically strongly bonded, but also the heat sealing material is At this time, these silane monomers present on the surface of the heat sealing material firmly bond to the glass surface, and the adhesive force between the heat sealing material and the opening surface of the glass container becomes extremely strong.

Therefore, it has excellent adhesion even to surfaces that are porous and have relatively weak polarity, such as the mouths of glass containers, and can quickly attach lids to the mouths of sealed packaging containers. Not only can the mouth of the glass container generally be hydrophilic, but also when the contents of the container are liquid or viscous substances such as alcohol, juice, or jam. In addition, it is possible to reliably prevent water from entering the heat-sealed adhesive part, greatly increasing the water resistance of the heat-sealing adhesive part, and reducing the decrease in adhesive strength in a water environment.
Good adhesion can be maintained for a long period of time, and sealing performance is improved under easy-open conditions.

Further, according to the heat-sealing lid material of the present invention, after filling food with food as in the past, a metal cap can be caulked to the mouth of the container, a metal or synthetic resin screw cap can be screwed, or a crown can be screwed onto the mouth of the container. Since the container is not covered or sealed, it is easy to open, and the sealing cost of the hermetically sealed packaging container is reduced because no cap or crown is used.

Furthermore, there is no resin left at the container mouth when the container is opened, so the appearance of the container mouth is clean after opening, and heat sealing can be performed at a relatively low temperature, making it easy to install filling and sealing equipment. This has the effect of reducing costs and operating costs, and improving the workability of filling and sealing.

[Brief explanation of the drawing]

Fig. 1 is a partially enlarged cross-sectional view showing a specific example of the product of the present invention;
The figure is a partially enlarged sectional view showing yet another specific example, and FIG. 3 is a partially enlarged sectional view showing yet another specific example. (1)... Aluminum foil, (2)... Heat sealing material layer, (3)... Adhesive layer, (4)... Anti-corrosion coating layer,
(5) Coating layer of silane monomer. Patent applicant Showa Aluminum Co., Ltd. Figure 1 Figure 2

Claims (3)

[Claims] (1) Silane monomer is present on the surface to be thermally bonded to the mouth of the sealed packaging container;
Heat-sealing lid material for sealed packaging containers. (2) A heat sealing material layer containing a silane monomer is provided on one side of the metal foil, so that the silane monomer is present on the surface to be thermally bonded to the mouth of the sealed packaging container. The heat-sealing lid material according to claim 1. (3) A heat sealing material layer is provided on one side of the metal foil, and a coating layer made of silane monomer is provided on the surface of the heat sealing material layer, so that the surface to be thermally bonded to the mouth of the sealed packaging container is 2. The heat-sealing lid material according to claim 1, wherein a silane monomer is present.