JPS61280928A - Packaging material using iron or steel foil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a packaging material using iron or steel foil, and more particularly, it relates to a packaging material using iron or steel foil, and more particularly, it has excellent corrosion resistance, storage stability, appearance characteristics, and safety. Concerning packaging materials having a combination of gender.

(Prior art and technical problems of the invention) Packaging materials used for containers and lids include various materials such as metals, plastics, paper, glass, and ceramics, or composite materials of two or more of these materials. However, in terms of the combination of barrier properties against gases such as oxygen, carbon dioxide, and water vapor, and mechanical strength, metal materials are most suitable.

However, since metal cans and metal lids are difficult to dispose of by incineration, etc., there is a problem of so-called can pollution.As a packaging material that is easier to dispose of, a laminate consisting of metal foil and resin film is used. It has come to be widely used in the field of sealed containers and sealed lids. Almost all commercially available laminates for containers or lids are based on aluminum foil, but even though aluminum foil has excellent appearance characteristics and flexibility, its surface is Even when coated with organic resin, contents containing relatively high concentrations of salts such as common salt and contents containing organic acids can cause problems such as corrosion such as pitting and peeling of the coating layer. , resulting in defects such as leakage of contents and decreased shelf life.

Metal foils based on iron or steel, such as iron foil, steel foil, and tin foil, are also known, but there are still issues to be solved when using these as food packaging materials. There are many problems.

That is, iron and steel are metals that are extremely susceptible to rust, and rust can occur during the manufacturing process or storage of a package, which can significantly reduce its appearance and commercial value. Further, iron elution and rust contamination significantly reduce the flavor retention of the contents.

Furthermore, since iron or steel foil is significantly thinner than steel plate,
It has poor drawability and formability, and there are problems such as wrinkles occurring during drawing and the foil being cut, making it impossible to form a container. This drawback becomes more noticeable when a relatively thick organic resin coating is applied to iron or steel foil for the purpose of improving its corrosion resistance and rust resistance. The most serious problem is that iron foil or steel foil has greater rigidity than aluminum foil, and its thickness is generally comparable to that of a sharp cutting edge, so if your fingertip etc. touches the cut edge of this foil, , there is a problem of easy cuts. Furthermore, even if thorough care is taken to protect the surface of the iron foil, rust easily occurs from the exposed cut edges.

(Object of the Invention) Therefore, the object of the present invention is to eliminate the above-mentioned drawbacks that occur when iron foil or steel foil is used as a packaging material.

Another object of the present invention is to provide a packaging material using iron or steel foil that has an excellent combination of corrosion resistance, storage stability, appearance characteristics, and safety.

Still another object of the present invention is to provide a packaging material useful for use as a hermetically sealed container or lid for filling foods.

(Structure of the Invention) According to the present invention, the thickness of iron or steel is 5 to 120 mm.
It is composed of a laminate consisting of a micrometer foil base, a surface treatment layer provided on the foil base consisting of a metal plating layer or a chromate layer, and an organic resin coating provided through the surface treatment layer. At least one surface of the foil substrate is provided with an organic resin coating layer having a blocking effect against corrosive components and having a metal or pigment sufficient to have a concealing effect, and the organic resin coating on the foil substrate is entirely covered. as 15 to 2
A packaging material is provided, characterized in that it has a thickness of 00 μm.

(Preferred Embodiments of the Invention) The present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.

Packaging material and its effects Figure 1 shows the basic cross-sectional structure of the packaging material of the present invention, with the upper side being the outer surface side and the lower side being the inner surface side (the side in contact with the contents). (The same applies to the following drawings).

This packaging material consists of an iron or steel foil 1 with a thickness of 5 to 120 μm, a surface treatment layer 2a consisting of a metal plating layer or further a chromate layer applied to the inner surface of the foil, and the surface treatment layer 2. It has an organic resin inner surface coating 4 provided via an adhesive layer 3a if necessary. In this specific example, a surface treatment layer 2b is similarly provided on the outer surface side of the iron or copper foil 1, and a metal or pigment type organic resin outer surface coating 5 is applied thereon via an adhesive layer 3b if necessary. It is provided.

In the present invention, iron or steel foil is used because, compared to aluminum foil, this foil has a significantly lower pitting corrosion rate for contents containing salt.
This can significantly improve the corrosion resistance and gas barrier properties of the packaging material.

Further, iron or steel foil has a Young's modulus about 2.5 times that of aluminum foil, and can provide sufficient strength and shape retention with a relatively thin thickness. Furthermore, iron or steel foil is relatively inexpensive to obtain compared to aluminum foil, and can also reduce the cost of packaging materials.

This iron or steel foil has a thickness of 5 to 120 x rn, especially 8
It is also important to have a thickness of 100 μm. If the thickness is less than the above range, it is difficult to obtain a foil without defects such as pinholes, and it is difficult to obtain sufficient barrier properties against various gases, water vapor, etc. Moreover, if the above range is exceeded, the final container or lid becomes too rigid, which tends to make disposal difficult or to cause problems with the cut edge cover described below. The preferred range varies depending on the application, but for example, in the case of Tezo tabs (opening pieces for lids), it is 10 to 40 μm.

Appropriate ranges are 5 to 30 μm for pouch products, 30 to 120 μm for squeeze-formed containers, and 10 to 120 μm for heat-sealed lids, but the present invention is of course not limited to the exemplified applications. .

In the present invention, from the viewpoint of corrosion resistance and adhesion of the organic resin coating, it is preferable to provide the iron or steel foil 1 with a surface treatment layer consisting of a metal plating layer or a chromate layer thereon. extremely important.

Although organic resin coatings are effective in preventing direct contact between the contents and iron or steel foil, the resin and resin coatings are effective in preventing direct contact between the contents and iron or steel foil. It has the property of allowing hydrogen ions to pass through it fairly easily, and anions such as chloride ions contained in salts also pass through it, albeit to a small extent.

For this reason, peeling of the coating tends to occur at the interface between the organic resin coating and the foil, and once such peeling occurs, corrosion such as formation of pitting, iron elution, and pitting easily progresses in this area. Become.

According to the present invention, by providing a surface treatment layer consisting of a metal plating layer or further a chromate layer on iron or steel foil, this metal plating layer acts as a barrier layer against the above-mentioned corrosive components, and furthermore, the organic resin It acts to increase the adhesion with the coating layer.

At this time, when a chromate layer is provided on the metal plating layer, the adhesion with the organic resin coating is further improved.

The metal plating layer may be a metal that is softer than iron and exhibits a corrosion-preventing effect on iron, such as Nl or Sn.

Metals such as Zn and At are advantageously used. The plating layer made of these metals not only has an excellent anti-corrosion effect, but also when cutting iron or steel foil, the plating layer metal flows to the cut edge, protects the cut edge, and prevents corrosion from the cut edge. It shows an unexpected and novel effect of suppressing the occurrence of rust.

The fact that the plating layer metal flows and exists at the cut edge of iron or steel foil with this plating layer is due to the presence of the plating layer metal when the cut edge is observed with an X-ray microanalyzer. will be confirmed.

Generally, the hardness of the metal plating layer is Vickers hardness Hv.
500 or less, preferably 400 or less metal is 0
．． 1 to 15 g/fn, especially 0.2 to 1211/m
Preferably, it is present in a coverage of 2. That is, if the metal has a hardness exceeding the above range, the plating layer metal will not flow to the cut edge when cutting iron or steel foil, and the rust prevention effect at the cut edge will not be achieved. Further, when the amount of metal plating is at the end of the above range, the effect of blocking corrosive components or preventing corrosion is unsatisfactory, and in particular, the effect of preventing rust from occurring on cut edges cannot be obtained. Furthermore, it is economically disadvantageous to provide the plating layer beyond the above range, which offsets the advantage of using iron or steel foil.

A nickel-plated layer is particularly effective in shielding corrosive components, and tin-plated foil, ie, tin foil, is an easily available plated iron or steel foil. This tin foil has a relatively small amount of tin coverage, for example 0.5 to 10 f! /m2, sufficient corrosion resistance and organic film adhesion can be obtained.In this case, the tin layer may exist as a metal tin layer, but in terms of resin adhesion, Sn/F
Preferably, it is present in the form of a tin-iron alloy layer with an e-metal atomic ratio in the range of 2 to 1.

As for the chromate layer, the coating amount as Cr is 1 to 5.
Mention may be made of a chromium oxide layer mainly composed of hydrated chromium oxide in the range of 0 to 351 n9/m2, especially 3 to 351 n9/m2. This chromate layer can be formed on the above-mentioned plating layer by a known chemical conversion treatment and/or chemical treatment.

In the present invention, for applications in which rust formation at the cut edges is not a problem, such as draw-formed containers with curled edges, the plating layer is a metallic chromium layer, and a nine-layer coating having a chromate layer on top of the metal chromium layer is recommended. - Free steel foil may be used. This metallic chromium layer has a thickness of 0.03 to 0.5. It is preferably present in a coverage of F/m2, especially 0.05 to 0.31/m2.

Furthermore, the metal plating layer is not limited to being composed of a single metal layer, but can also be composed of a plurality of different types of metal layers. For example, the base plating layer is the above-mentioned soft metal layer such as nickel, the top plating layer is a chromium metal layer formed by electrolytic chromic acid treatment, and further has a chromium oxide layer thereon. good.

In the present invention, on the above-mentioned surface-treated iron or steel foil,
An organic resin coating is provided, and in this case, one or both of the organic resin coatings include metals or pigments that have the effect of improving processability and have a blocking effect and a concealing effect against corrosive components. It is also important to use That is, by using a coating containing the above-mentioned metal or pigment, the workability of iron or steel foil is improved. For example, as mentioned above, iron or steel foil is significantly inferior in drawability and formability to steel sheets due to the thickness effect. This is because wrinkles occur during the drawing process.To prevent wrinkles,
This is because even if the wrinkle suppressing force is increased, the wrinkle suppressing force is not sufficiently transmitted to the foil surface through the organic film. Furthermore, if the wrinkle pressing force is increased too much, iron or steel foil has low strength and will break, making it impossible to form a container.

Since the metal or pigment in the organic resin coating makes the organic resin coating itself hard, it is thought that the wrinkle-pressing force is efficiently transmitted to the foil, making it possible to form a wrinkle-free squeezed container.

Furthermore, by using a coating containing the metal or pigment described above, the tendency to corrode the corrosive components iron or steel foil is significantly suppressed, and, for example, hydrogen generation is significantly suppressed, thereby extending the shelf life of the container. In addition, even if rust occurs on the iron or steel foil during long-term storage, this rust is hidden, and the appearance characteristics are maintained well over a long period of time, thereby increasing the commercial value.

As a metal having both of the above-mentioned functions, a deposited layer of metallic aluminum can be mentioned, and this deposited layer is.

0.01 to 0.2μ on the surface of a film such as polyethylene terephthalate or casting polypropylene.
m, in particular 0.03 to 0.1 μm, are advantageously used. When this aluminum vapor-deposited film layer is provided, the packaging material has a particularly strong metallic luster and is excellent in shelf life. - Further, examples of pigments having both of the above-mentioned functions include titanium dioxide, particularly rutile titanium dioxide.

This titanium dioxide has the highest anticorrosion effect among various pigments against the corrosion of steel foil and other materials caused by corrosive components, and it also has excellent hiding power, making it possible to permanently maintain the white color of packaging materials. becomes possible. This titanium dioxide is a resin film.

It is contained in an adhesive layer or paint, and provided so that the coating amount of titanium dioxide is 0.5 to 30 J/m2, particularly 1 to 20 J/m2. In place of titanium dioxide or in combination with titanium dioxide, aluminum flake pigments, tin oxide pigments, zinc oxide pigments, etc. can be used as pigments having both of the above-mentioned functions. The coating amount can be in accordance with the above range.

In the present invention, it is also extremely important from the viewpoint of workability and moldability that the overall thickness of the organic resin coating layer is 15 to 200 μm, particularly 20 to 180 μm, and more preferably 30 to 160 μm. As already pointed out, the cut edge of iron or steel foil is a sharp knife, and touching it can easily cause damage to fingers, etc. However, according to the present invention, the resin coating layer of the above-mentioned thickness can be By providing this, the above-mentioned risks are completely eliminated,
This makes it possible to establish the safety of packaging materials using iron or steel foil. That is, if the thickness is less than the above range, it is difficult to eliminate the risk of cut edges, while if it exceeds the above range, the moldability and processability into containers and lids will deteriorate.

Laminated Structure The packaging material of the present invention can have various laminated structures other than the cross-sectional structure shown in FIG. 1 within the range that satisfies the above-mentioned limitations.

Several examples will be described below, but the packaging material of the present invention is of course not limited to the laminate structure illustrated.

Figure 2 shows a laminate suitable for use as a Chiebuta-type tear-off piece for easy-to-open container lids. layer, metallic chromium layer and chromium oxide layer (hydrated chromium oxide layer)
Surface treatment layers 2a and 2b are provided. An inner surface protection resin layer 4 such as a vinyl chloride resin organosol paint is provided on the inner surface side via the surface treatment layer 2a. On the other hand, the outer surface protective resin coating 5 is composed of a polyester film (biaxially oriented heat-set ethylene terephthalate film) 7& provided with a metal aluminum vapor deposited layer 6, and a polyester film 7b provided with a printing ink layer 8. The vapor deposited layer 6 and the ink layer 8 are stacked on top of each other via the adhesive 3c so as to face each other, and the vapor deposited layer 6 is placed on the iron foil via the adhesive layer 3b in a positional relationship such that the vapor deposited layer 6 is on the inside and the ink layer 8 is on the outside. is bonded to the surface treated layer 2b.

This laminated structure Tegu Tap has a nickel plating layer on both surfaces, so the flow of the plating layer metal almost completely prevents rust from forming on the cut edge. Due to the chromium oxide layer, the combination of corrosion resistance and organic coating adhesion is
Excellent.

Furthermore, since it is covered with a thick resin film layer, the safety of the cut edge is high, and furthermore, the appearance characteristics and commercial value can be permanently maintained due to the presence of the vapor deposition layer and the ink layer.

Figure 3 shows a laminate suitable for use as a draw-formed container such as a container with a flantz or a metal cap formed by draw-forming. Surface treatment layers 2a and 2b made of metallic chromium layers are provided. On the inner surface side, an inner surface protective coating layer 4 made of polyethylene or polypropylene containing titanium dioxide is provided via an adhesive layer 3a made of acid-modified olefin resin or urethane resin. On the outer surface side, an outer protective coating layer 5 made of polyethylene, polypropylene, nylon, polyester, etc. containing titanium dioxide is provided via a similar adhesive layer 3b, and printed on this outer protective coating layer 5. An ink layer 8 is formed.

The draw-formed container or container lid made of this laminated structure is
By having a combination of an electrolytic chromic acid surface treatment layer and a titanium dioxide-containing resin layer on both surfaces of the steel foil, it has particularly excellent corrosion resistance and good appearance characteristics. It also has the advantage of providing sufficient shape retention.

FIG. 4 shows a laminate used for drawing-formed containers or container lids, as in the case of FIG. 3, and the difference from FIG. 3 is that the surface treatment layer 2a on the steel foil 1 is , 2b are made of a plated metal tin layer or a tin-iron alloy layer. This tin steel foil is preferably, as described below,
It is obtained by cold rolling a pre-tinned steel sheet, and this rolling process forms a completely continuous tin-iron alloy layer between the copper base metal and the tin-plated layer, which provides corrosion resistance and organic properties. This has the advantage of particularly excellent adhesion of the resin coating. The inner resin coating layer 4 is one containing titanium dioxide as in the case of FIG. 3, but the outer resin coating layer 5 may be one containing titanium dioxide as in the case of FIG. When the metallic luster of the plating layer is maintained, the addition of titanium dioxide may be omitted.

FIG. 5 shows a laminate suitable for manufacturing a retort bag, that is, a sealed packaging bag for sterilization. As in the case of FIG. ,
Surface treatment layer 2 consisting of a metal chromium layer and a chromium oxide layer
a and 2b are provided.

For the purpose of protecting the inner surface and imparting heat-sealability, a heat-sealable inner material layer 4 made of polyethylene, polypropylene, etc. is provided on the inner surface side with an adhesive layer 3a interposed therebetween.
On the outer surface side, a resin film 7 having a vapor deposited layer 6 of metal aluminum is placed on an adhesive layer 3 with the vapor deposited layer 6 on the inside.
They are bonded together via b. A printing ink layer 8 is provided on the outer surface of the film 7.

This laminate also has the same advantages as shown in FIG. 2, as well as the advantage that it is easily opened by tearing, especially in connection with the use of iron foil.

FIG. 6 shows a laminated lid material suitably used for manufacturing heat-sealed lids, especially easy-to-open heat-sealed lids. and a chromium oxide layer) 2a, 2b are provided. On the inner surface side, if necessary, on the surface treatment layer 2a),
A heat-sealable inner protective layer 4 made of polyethylene containing titanium dioxide and 4-lipropylene is provided via the adhesive layer 3, and a thermosetting protective layer such as epoxy-phenolic paint is applied to the outer surface. A covering layer 5 is provided. This protective coating layer 5 also serves as an adhesive primer, and it is easy to attach an opening tab or the like using a thermal adhesive such as -lyamide or copolyester.

material Various materials used in the present invention will be explained in more detail.

As a foil base, 1. Iron foil is used when flexibility or pliability is required, and steel foil is used when rigidity or mechanical strength necessary to maintain shape is required.

Iron foil is obtained by electrodepositing an electrolyte containing ferrous chloride, ferrous sulfate, etc. onto the surface of a metal substrate as a cathode, and then peeling the formed film from the surface of the substrate. It has extremely high purity ((over 99.97% Fe)), excellent corrosion resistance9, and has softer properties than steel foil. Iron foil has a long, elongated structure, whereas iron foil has a columnar crystal structure in which crystals grow in the thickness direction.

Both ductiles and full hard steel foils are used. For the pre-applied type, after annealing the cold-rolled steel plate, it is subjected to secondary cold rolling, re-annealing, and if necessary, galvanizing, tin plating, nickel plating, electrolytic chromic acid treatment, and chromic acid treatment. It can be obtained by performing one or more types of treatments. For the latter type, cold-rolled steel sheets are annealed and then subjected to secondary cold rolling, and if necessary, post-treatments such as zinc plating 1, tin plating, nickel plating, electrolytic chromic acid treatment, chromic acid treatment, etc. are performed. You can get it easily. Full hard type with metal plating layer is also available after annealing the cold rolled steel plate.
It can also be manufactured by performing secondary cold rolling after processing and metal plating.

An example of the mechanical properties of soft steel foil, hard steel foil, and iron foil is as follows.

, Tensile strength and elongation are generally 30 to 50 s/IW+2 and 15 to 35 s/IW+2, respectively for soft steel foil, and 40 to 60, 97w5 and 1 to 15% for hard steel foil, respectively.
With iron foil, it is 30-50 and 97wm, 2-10
'16 range.

The organic resin coating used is a thermoplastic resin, a thermosetting resin or a combination thereof, which can be applied in the form of a preformed film or in the form of a paint. Suitable examples of such resins include, but are not limited to:

(a) f lyolefins; 4-lipropylene, polyethylene, polybutene-1, f-propylene-ethylene copolymer, goupylene-butene-1 copolymer, polymer, ethylene-vinyl acetate copolymer, ionically crosslinked olefin copolymer ( ionomer).

(b)/Ryamides: especially general formula % formula % (1) In the formula, n is a number from 3 to 13, and m is a number from 4 to 11. Tetraamides consisting of the repeating unit represented by

For example, poly-ω-aminohebutanoic acid, poly-ω-aminohebutanoic acid, poly-ω-aminocaprylic acid, poly-ω-aminocaprylic acid, poly-ω-aminocaprylic acid, poly-ω-aminohebutanoic acid,
-Aminopera is inic acid s't'') -ω-aminodecanoic acid, ?soω-aminoundecanoic acid, 4-ω-aminododecanoic acid, pre-ω-aminotridecanoic acid, -lyhexamethyleneazinogumide, polyhexane methylene sebamide, polyhexamethylene r-decamide, ?lihexamethylene tridecamide, polydecamethylene azinogumide, polydecamethylene dodecamide, polydecamethylene dodecamide,
? Ridecamethylene tridecamide, polydodecamethylene azino or mido, polydecamethylene dodecamide, polydodecamethylene dodecamide, I lidodecamethylene tridecamide, ? Litridecamethylene adipamide, polytridecamethylene dodecamide, polytridecamethylene dodecamide, ?
Litridecamethylene, tridecamide, polyhexamethylene azelamide, polydecamethylene dodecamide, polydecamethylene dodecamide, polytridecamethylene dodecamide, or coiramides thereof.

(c) Bori esters: General formula % Formula % (4) In the formula, R4 is an alkylene group having 2 to 6 carbon atoms, and R2 is an alkylene group or arylene group having 2 to 24 carbon atoms. Polyester consisting of units.

For example, polyethylene terephthalate, polyethylene terephthalate/'inphthalate, polytetramethylene terephthalate, polyethylene/tetramethylene terephthalate, ? Litetramethylene terephthalate/isophthalate, ? Diethylene terephthalate/isophthalate, polytetramethylene/ethylene terephthalate, polyethylene/tetramethylene terephthalate/isophthalate, polyethylene/oxybenzoate, or blends thereof.

(d) Polycarbanates: especially the general formula % formula % (5
) A polycargenate represented by the formula in which R3 is a hydrocarbon group having 8 to 15 carbon atoms.

For example, poly-p-xylene glycol;-lupiscarbonate, poly-dioxydiphenyl-methane carbonate,
Polydioxydiphenylethane carbonate, poly-
Dioxydiphenyl 2.2-frobanker & na-),?
Di-dioxydiphenyl 1,1-ethanecar? Nate.

(e) Vinyl chloride resins such as polyvinyl chloride, vinyl chloride-butadiene copolymer, and vinyl chloride-styrene-butadiene copolymer.

(f) vinylidene chloride-vinylidene chloride copolymer,
Vinylidene chloride resin such as vinylidene chloride-vinylpyridine copolymer.

(g) High nitrile resins such as acrylonitrile-butadiene copolymers, acrylonitrile-styrene copolymers, and acrylonitrile-styrene-butadiene copolymers with high nitrile content.

(h) Polystyrene resin, styrene-butadiene copolymer, etc.

These resins are generally formed into a film and adhered to the above-mentioned steel foil by heat fusion, or bonded using an adhesive. Adhesives that are excellent for a wide range of thermoplastic resin films and steel foils are urethane-based adhesives, and for polyolefin films, adhesives that are graft-modified with ethylenically unsaturated caldic acid or its anhydride are suitable for use with polyolefin films. Acid-modified olefin resins can be used as adhesives, and low melting point F polyamides can be used as adhesives for polyamide films, and low melting point copolyesters can be used as adhesives for polyester films.

An organic resin paint can also be used instead of the above-mentioned thermoplastic resin film. Such paints include any protective paints consisting of thermosetting and thermoplastic resins: modified epoxy paints such as phenolic epoxy paints, amino-epoxy paints, etc., such as vinyl chloride-vinyl acetate copolymers, vinyl chloride- partially saponified vinyl acetate copolymer,
Vinyl or modified vinyl paints such as vinyl chloride-vinyl acetate-maleic anhydride copolymers, epoxy-modified, epoxyamino-modified, or epoxydiphenol-modified vinyl resin paints, acrylic resin paints: styrene-butadiene copolymers, etc. Synthetic rubber paints and the like may be used alone or in combination of two or more.

These paints can be applied in the form of an organic solvent solution such as enamel or caramel, or in the form of an aqueous dispersion or solution, or in the form of roller coating, spray coating, dipping coating, electrostatic coating, pneumatic coating, etc. Apply to metal material in advance. Of course, if the resin paint is thermosetting, the paint may be baked if necessary.

Applications The packaging material of the present invention can be used in various ways to produce sealed packages, such as draw-formed containers, materials for four-door containers, various heat seal lids, draw-formed container lids, tape tabs, and materials for forming other containers. In either case, the various advantages mentioned above are achieved.

In addition to these advantages, the packaging material of the present invention has the advantage of having ferromagnetism inherent in iron foil and steel foil, which is not found in aluminum foil. Therefore, when the packaging material of the present invention is used for heat sealing, strong electromagnetic coupling with the coil occurs during high frequency induction heating, and as a result, the heating required for heat sealing or thermal bonding can be completed in an extremely short time. It has the advantage of being carried out efficiently.

The following examples specifically explain the effects of the present invention.

Tests were conducted in the following manner throughout each Example and Comparative Example.

(1) Inner surface condition After filling the container with the contents and storing it at room temperature for 2 years, open the container, remove the contents from the container, and wash lightly with tap water. The corrosion state and the state of the organic coating on the inner surface of the container were observed using a stereomicroscope.

(2) External Condition Test Regarding the external surface of the container in (1), the state of corrosion and the state of the organic coating were observed with the naked eye, and the appearance was evaluated at the same time. Appearance evaluation was conducted from the viewpoint that the more metallic luster and the brighter the color tone, the better.

(3) Rust test on cut edges Regarding the containers of (1), the cut edges were observed with a stereomicroscope and evaluated using a 5-point method.

5: No rust 4: The length of the rusted part is less than the 5th factor of the length of the entire cut 3:
'# 10% or less 2:
I Section 30 and below 1:
I Section 31 and above (4) For cut edge safety tape/tabs, the cut edge area around the tab,
For heat-sealed lids and retort pouches, the cut edges around the lid and the pouch, and the cut edges created by opening, respectively, have a thickness of 6411/
A cut was made at the edge of the paper of "frL", and the evaluation was made as follows.

5: The paper will not be cut at the cut edge.

°;1: Cut edge part 10c! Something that will not cut the paper even if you run it over IL.

3: Paper is cut by running the cut edge part 5 to 9.9 cm.

2: Paper is cut by running the cut edge part 1 to 4.9 cm.

1: Paper is cut even if the cut edge part is run less than 1α.

(5) Test for Hydrogen Generation Amount When the container of (1) was opened, the gas in the head paste of the container was collected above water, and the amount of hydrogen in the gas was analyzed by gas chromatography using a conventional method. The amount of hydrogen is almost directly proportional to the amount of corrosion on the inner surface of the container.

Examples 1 to 8 and Comparative Examples 1 to 7 were evaluated as tape tabs for tape-sealed cans.

In Example 1, first, a Watts bath (nickel sulfate 24011/J, dichloride,
Nickel was plated to a thickness of 41//m in an aqueous solution of Kel 45 N/A, 301//A of fluoric acid), and then electroplated with nickel in an electrolytic chromic acid treatment bath (601/J of chromic anhydride, 0/0 sulfuric acid,
21 inch, an aqueous solution of sodium silicofluoride (0.2 VJ) to obtain a 0.1117 m'' metallic chromium and No. 10 to 2 chromate layer.The hardness of the nickel plating produced in the Watt bath was was in the range of Iv 140 to Hv 220. Vinyl chloride was applied to one side of the thus obtained surface-treated iron foil.

An organosol type paint was applied so that the thickness after baking was 71 nn, and baked at 240° C. for 30 seconds.

Next, a polyester film with a thickness of 50RrlL, on which 0.08-thick aluminum has been vapor-deposited in advance, is laminated on the other side using a urethane adhesive (thickness 3μ) to form a tape tab material of 2crn x 4crrL. It was punched out to the size of , and made into tape tab pieces.

Using this tape tab piece, a tape seal lid having an outer diameter of 67 tas was manufactured according to the manufacturing method for easily openable container lids of Japanese Patent Publication No. 59-52096.

This tape-sealed lid is attached to the adhesive can body for a 250 gram can with an inner diameter of 52° and 3 ffil, which is made of a 0.22 m thick TFS plate and has already been double-sealed with a regular container lid on the other end. Canned fruit juice beverages were prepared by heat filling at 93°C and double sealing.

After storing these cans for 2 years, the inner and outer conditions of the tape tab, rust on the cut edges, and safety of the cut edges were evaluated. The results are shown in Table 1.

Example 2.3.4 Example 2.3.4 is a sister example except that the organic coating on the inner surface of the tape tab was changed to 5-, 8□, and 3 μm, and the organic coating on the outer surface of the tape tab was changed to 35 μm, 12 μm, and 12 μm, respectively. Tests and evaluations were conducted in the same manner as in 1. The results are shown in Table 1.

Comparative Example 1 In Comparative Example 1, the organic coating on the inner surface of the tape tab was changed to 5 μm.
The test was carried out in the same manner as in Example 1, except that the outer organic coating material of the tape tab was the same as the inner organic coating material and the thickness was changed to 5 μm.
We conducted an evaluation. The results are shown in Table 1.

Comparative Example 2 In Comparative Example 2, tests and evaluations were carried out in the same manner as in Example 1, except that an organic coating was applied to the outer surface of the tape tab.

Comparative Example 3 In Comparative Example 3, tests and evaluations were carried out in the same manner as in Example 1, except that a 50 μm thick phosphoric acid chromic acid treated (chromium amount: 10 m97 m2) aluminum foil was used as the foil material.

Example 5 In Example 5, nickel was plated on both sides of a 25-thick electrolytic iron foil to a thickness of 0.51/m2 in a Watt bath, and then in a chromate treatment bath (an aqueous solution of 20 Ih of chromic anhydride). In the chamber, cathode electrolysis was performed to perform chromate treatment at a rate of 20 mQ/m2.

On the thus obtained surface-treated iron foil, in the same manner as in Example 1, 8 μm thick polyvinyl chloride paint was coated on one side and 35 μm thick polyester film was coated with aluminum on the other side to a thickness of 0.05 μm. A film was provided, and then cans similar to those in Example 1 were prepared and tested and evaluated. The results are shown in Table 1.

In Example 6 and Comparative Example 4, the thickness of the nickel plating on the iron foil was 0.151/m" and 0.0917WL", respectively.
Tests and evaluations were carried out in the same manner as in Example 5, except for changing to .

Comparative Example 5 In Comparative Example 5, both sides of an electrolytic iron foil with a thickness of 25 μm were coated in a Sargent bath (chromic anhydride 2501/J, sulfuric acid 2.5!A).
Tests and evaluations were conducted in the same manner as in Example 5, except that chromium was plated to a thickness of 0.217 mm using an aqueous solution of The hardness of the chrome plating produced in the Sargent bath is Hv.
It ranged from 510 to Hvl, 000. The results are shown in Table 1.

Comparative Example 6 Comparative Example 6 was tested and evaluated in the same manner as Example 15 except that the surface treatment of the iron foil was not performed.

The results are shown in Table 1.

In Examples 7 and 8 and Comparative Example 7, the thickness of the vapor-deposited aluminum placed on the polyester was 0.03 mm, Q,
Tests and evaluations were carried out in the same manner as in Example 5, except that Ql was 0.005 μm. The results are shown in Table 1.

Examples 9-23. Comparative Examples 8 to 14 were evaluated using containers in which a draw-formed container was combined with a heat-sealed lid.

Example 9 In Example 9, a rolled steel foil with a thickness of 70 mm was electrolyzed cathodically in the electrolytic chromic acid treatment bath of Example 1, and a thickness of 0.11/m was formed on both sides.
01
A 70 μm thick polypropylene film containing 1/m” of titanium white was laminated on the outside of the container, and a 40 μm thick polypropylene film containing 5777 m1 of titanium white was laminated on the outside of the container.

The organic coated steel foil obtained in this way was pressed with a bottom diameter of 66 cm.
A cylindrical 7-lunged container with a height of 32 cm was formed. The tip of the 7th rung was curled to hide the cut edge.

On the other hand, both sides of a rolled steel foil with a thickness of 40 μm were plated with nickel to a thickness of 2.0117 WL” in a Watts bath, and then cathodically electrolyzed in the electrolytic chromic acid treatment bath of Example 1 to a thickness of 0.05 μL.
After obtaining the metallic chromium layer of 17- and the chromate layer of 15-damage, an epoxy phenol paint containing titanium white was applied to one side so that the thickness after drying was 54 (amount of titanium white 51/m2) and heated at 250°C. A 40μ thick polypropylene film containing 51i/mN titanium white was laminated on the other side using a urethane adhesive.

A heat-sealed lid was prepared by punching out the organic-coated steel foil obtained in this way into a circle with a diameter of 701 m, with one portion having a triangular grip.

Next, the container was filled with tuna dressing and the lid was heat-sealed, followed by heat sterilization at 116° C. for 40 minutes. After storage for 2 years at room temperature, the squeezing force, the inner and outer conditions of the container and lid, the force of the lid, the rust on the toe and the lid,
We evaluated the safety of the space, space, and space, and measured the amount of hydrogen generated in the space. The results are shown in Table 2.

Example 10.11.12. Comparative Example 8.9 Example 10.1
1, 12, Comparative flJ8.9 has a titanium white content of 577/m2,
l 77/vl, Q, 597m", 0,2 j
i/mfi.

OII/4! The titanium white content of the outer organic coating was changed to 31/m'', 1.51/track, and 0.
51b value! , 0.21//m2.011. Tests and evaluations were carried out in the same manner as in Example 9 except that YC2 was used.

The results are shown in Table 2.

In Example 13.14i5 and Comparative Example 10, the squeezing force and the amount of chromate due to snow melting chromic acid treatment of the steel foil of the container were reduced by 10%.
As the inner organic coating, the thickness of the polypropylene film with a titanium white content of 1017 m2 was 90 μm, 90 μm, 95 □, and 100 ArrrL, respectively, and as the outer organic coating, the titanium white content was 1011/m2.
The thickness of 4 polypropylene films of 60 m” each
μm, 80μffl', 95μm.

100 μm, and the amount of nickel plating on the lid was 1. Q l
/rn”.

The chromium plating area is 0.07117 m'', the chromate amount is 10 µ/m2, and the inner organic coating is a polypropylene film with a titanium white content of 61/m'', with a thickness of 25 μrn and 15 #? X, l Ottm, l
QRrlL, and the thickness of the polypropylene film with a titanium white content of 5y, , m2 as the outer organic coating is rm, 5urrL, 5#, respectively.
l) Testing and evaluation were conducted in the same manner as in Example 9 except that tm was used. The results are shown in Table 2.

Example 16 In Example 16, a rolled steel foil with a thickness of 50 trm was electrolyzed cathodically in the electrolytic chromic acid treatment bath of Example 1, and a thickness of 0.1 trm was formed on both sides.
After obtaining 517' of metallic chromium and 20/- of chromate layer, a urethane adhesive was applied.A 50 μm thick polypropylene film containing 1017'In'' of titanium white was applied to the inner surface of the container, and a 50 μm thick polypropylene film containing 1017'In'' was applied to the outer surface of the container. On the side, titanium white 51
Laminated with a 30-m2 thick polypropylene film.

A drawn cup container was formed from the organic coated steel foil thus obtained in the same manner as in Example gA, +9.

On the other hand, both sides of a rolled steel foil with a thickness of 100 μm were plated with 1297 m thick in a Watts bath, and then cathodic electrolysis was performed in the chromate treatment bath of Example 5 to perform a 20μX- chromate treatment. After that, one side is coated with titanium white-containing epoxy.
Phenol paint was applied so that the dry thickness of 5p titanium white was 517m2, and baked at 250℃ for 30 seconds, and the other side was coated with 6517m'' of titanium white, 30m2 thick using urethane adhesive. A polypropylene film was laminated. A heat-sealed lid was made from the organic coated steel foil obtained in the same manner as in Example 9.

Next, the same tests and evaluations as in Example 9 were conducted.

The results are shown in Table 2.

Examples 17 and 18 and Comparative Example 11 In Examples 17 and 18 and Comparative Example 11, the thickness of the steel foil of the heat seal lid was 1101 rrrL and 120 μm, respectively.

Tests and evaluations were conducted in the same manner as in Example 16 except that the thickness was changed to 130 μm. The results are shown in Table 2VC.

Comparative Example 12 In Comparative Example 12, 1 piece of foil was used for the squeezed container and 1 piece for the lid.
Tests and evaluations were performed in the same manner as in Example 16, except that aluminum foil of 20 μm and 100 urrL was used.

Example 19 Example 19 has a thickness of 50#! The rolled steel foil was cathodically electrolyzed in the electrolytic chromic acid treatment bath of Example 1 to give a thickness of 0.317 mm on both sides.
After obtaining a chromium metal layer of 20 m/m and a chromate layer of 20 m/m, a 50 mm thick polypropylene film containing 1097 m2 of titanium white was applied to the inner surface of the container using urethane adhesive, and a 50 mm thick polypropylene film containing 1097 m2 of titanium white was applied to the outer surface of the container. For the titanium white 51/
A 4 mm thick polypropylene film containing Im2 was laminated. The organic coated steel foil thus obtained was drawn into a container in the same manner as in Example 9.

On the other hand, both sides of a rolled steel foil with a thickness of 50 μm were plated with nickel to a thickness of 3777 m2 in a Watts bath, and then cathodically electrolyzed in the chromate treatment bath of Example 5 to perform a chromate treatment of 10 μm/m''. One side was coated with titanium white-containing epoxy-phenol paint so that the thickness after drying was 51nnS, and the amount of titanium white was 5mm, and baked at 250℃ for 30 seconds.The other side was coated with urethane adhesive. 6.p/m
A titanium-containing polypropylene film with a thickness of 4Qg was laminated.

A heat-sealed lid was prepared in the same manner as in Example 9 from the organic coated steel foil thus obtained.

Next, the same tests and evaluations as in Example 9 were conducted.

The results are shown in Table 2.

Examples 20.21, 22, Comparative Example 13.14 Example 20
．． In No. 21.22 and Comparative Example No. 13.14, the amount of chromium plating on the squeeze container was 0.51/m2.

0.061/Im2.0.04 Film", 0.
021/m'' and 0.6 g/m2, the same tests and evaluations as in Example 19 were conducted. The results are shown in Table 2.

Example 123 Example 23 has a thickness of 5Q as a foil for squeezed containers and lids.
Example 19 except that tin layer-plated rolled steel foil with a tin content of 0.81/Iml was used, and a polypropylene film without titanium white was used as the outer organic coating for the squeeze container and lid.
The same tests and evaluations were conducted. The results are shown in Table 2.

Examples 24 to 28 and Comparative Examples 15 to 18 were evaluated as retort pouches.

Example 24 In Example 24, both sides of an electrolytic iron foil having a thickness of 50 μm were coated with a tin plating bath (Tin 501!/A).

Stannous 201j/A, free cilantric acid 100.9/I
, 0.617 m2 of tin was plated in an aqueous solution of 25 kG of free phosphoric acid and 10 m/7 of formalin. The hardness of the tin layer obtained by this metallization was &40. After that, Example 1
In an electrolytic chromic acid treatment bath, cathode electrolysis was performed, and 0.031/
A chromate layer of Im2 metal chromium and 71rQlfrL" was obtained. The thus obtained surface-treated iron foil was coated with a 40μ thick polypropylene film containing 5 fl/m2 of titanium white on one side and a 40μ thick polypropylene film containing 5 fl/m2 of titanium white on the other side using a urethane adhesive. is 0
．． A 25 μm thick polyester film with a 0.05 μm vapor deposited aluminum layer was laminated.

From the organic coated iron foil obtained in this way, 10crrL×16cr
Punch out a rectangle of IL and make a set of 2 from polypropylene.
The film sides were placed one on top of the other, and three sides were heat-sealed to a width of 5 mm, except for one side with a length of 10 cm, to create a retort pouch. This retort container was filled with tomato stew, heat-sealed, and then heat sterilized at 120° C. for 30 minutes.

After being stored for two years at room temperature, the inner surface condition, outer surface condition, rust on the cut edge, and safety of the cut edge were evaluated.

Example 25 In Example 25, zinc chloride 3 was used as a surface treatment for electrolytic iron foil.
6011/Z, ammonium chloride 2301//J in nail polishing bath, thickness 1.0.9/ff12, hardness Hv 1
Test 1 and evaluation were conducted in the same manner as in Example 24, except that zinc plating was performed. The results are shown in Table 3.

Example 26 Example 26 is a surface treatment of electrolytic iron foil with a thickness of 1.01 mm.
/ML2, hard Hv 90 vapor deposited aluminum plating, no vapor deposited aluminum on the outer organic coating? The same tests and evaluations as in Example 24 were conducted except for using a lyester film. The results are shown in Table 3.

Example 27 Example 27 uses lead fluorosilicate 13011/I! as a surface treatment for electrolytic iron foil. = 1 in a plating bath consisting of an aqueous solution of 611/J of fluorosilicic acid and 0.51/A of gelatin.
・Tests and evaluations were conducted in the same manner as in Example 24, except that lead plating was performed with O97m2 and hardness Hv50.

The results are shown in Table 3.

Example 28 Example 28 uses copper cyanide 2 as a surface treatment for electrolytic iron foil.
09/A, cyanide soda 3011/J, carbonated soda 151
In a plating bath consisting of a 1/I aqueous solution, a thickness of 1.017
Tests and evaluations were conducted in the same manner as in Example 24, except that copper plating with a hardness of Hv180 was performed.The results are shown in Table 3.
Shown below.

Comparative Example 15 In Comparative Example 15, electrolytic iron foil was surface treated with rhodium sulfate (thickness 1.01/J, hardness) (v850) in a plating bath consisting of an aqueous solution of rhodium sulfate 711/l and sulfuric acid 20 ml/J. Tests and evaluations were conducted in the same manner as in Example 24 except for plating. The results are shown in Table 3.

Comparative Example 16 In Comparative Example 16, cobalt sulfate 500.9/7. Sodium chloride 151/J.

Tests and evaluations were conducted in the same manner as in Example 24, except that cobalt plating with a thickness of 1.0 μm and a hardness of Hv520 was performed in a plating bath consisting of an aqueous solution of boric acid 401/J. The results are shown in Table 3.

Comparative Example 17 Comparative Example 17 includes surface treatment of electrolytic iron foil, palladium ammonium chloride 61//J, ammonium chloride 91//
Tests and evaluations were carried out in the same manner as in Example 24, except that radium plating with a thickness of 1.01/A and a hardness of Hv 580 was performed in a plating bath consisting of an aqueous solution of Z. The results are shown in Table 3.

Comparative Example 18' In Comparative Example 18, chloroplatinic acid 1 was used as a surface treatment for electrolytic iron foil.
．． 511/e, ammonium phosphate 201/Z.

Thickness 1.01 in a plating bath consisting of an aqueous solution of sodium phosphate at 95 mm θ! /A, Tests and evaluations were carried out in the same manner as in Example 24 except that platinum plating with a hardness of Hv820 was performed. The results are shown in Table 3.

Examples 1 to 8 and Comparative Examples 1 to 7 are tape-sealed cans. Cape, Tsuyu 5. C-rated pot. .

From Examples 1 to 4 and Comparative Example 1.2, it can be seen that when the total organic coating thickness is 15 or less, the safety of the cut edge is significantly reduced. In addition, if an organic coating on the outer surface of Comparative Al 1 or Comparative Example 2 is used, or if no organic coating is provided on the outer surface, the appearance characteristics may be poor or problems may occur due to rust formation. I know it's going to happen. Furthermore, if aluminum foil is used instead of iron or steel foil as in Comparative Example 3, sufficient corrosion resistance cannot be obtained.

From Example 5.6 and Comparative Example 4.5.6, in order to obtain the rust prevention property of the cut edge, a corrosion-resistant metal with hardness or Vickers hardness of Hv500 or less is used with a thickness of 0.11/- to 1597 m.
It can be seen that it is necessary to set it within the range of ”.

From Example 1.7.8 and Comparative Example 1.2.7, in order to keep the appearance good for a long time, the metal thickness in the outer surface coating should be 0.01.
It can be seen that it is necessary to be in the range of ~0.2XrIL.

Examples 9 to 23 and Comparative flJ 8 to 14 were evaluated using containers in which a draw-formed container was combined with a heat-sealed lid.

From Examples 9 to 12 and Comparative Examples 8 and 9, in order to obtain a squeeze container with excellent corrosion resistance, container shape, and appearance, the amount of pigment in the organic coating should be in the range of 0.5 to 301/Zm''. It turns out that this is necessary.

From Examples 9, 13 to 15 and Comparative Example 10, it can be seen that in order to obtain a drawn container with excellent corrosion resistance and container shape, the total thickness of the organic coating must be in the range of 15 to 200 μm. It has also been found that the safety of the cut edge of the heat seal lid requires that the total thickness of the organic coating be in the range of 15 to 200 ttm.

From Examples 16 to 18 and Comparative Examples 11 and 12, in order to obtain a heat-sealed lid that is corrosion resistant and has excellent rust and cut edge safety, steel foil should be used and the thickness of the steel foil should be 5 to 120 μm. It turns out that it is necessary to be within the range.

From Examples 19 to 22 and Comparative Examples 13 and 14, in order to obtain a squeeze container with excellent corrosion resistance, the thickness range of metallic chromium must be 0.
．． 03 to 0.5/i/m2.

From Example 23, it can be seen that the drawn container and lid made from tin-plated rolled steel foil are excellent in corrosion resistance, cut edge rust, and cut edge safety.

Examples 24 to 28 and Comparative Examples 15 to 18 are retort No! I rated it as my own.

From Examples 24 to 28 and Comparative Examples 15 to 18, in order to have a retort couch with excellent corrosion resistance and cut edge rust prevention, the surface treatment of the iron foil must have an anticorrosive effect and a Vickers hardness. It can be seen that it is necessary to provide metal plating with a hardness of Hv500 or less in a thickness range of 0.111/m" to 15 f1/m".

Table 3 (continued)

[Brief explanation of drawings]

Figure 1 is a diagram showing the basic cross-sectional structure of the packaging material of the present invention, Figure 2 is a cross-sectional diagram of a laminate suitable for use as a tape tab for easy-open container lids, and Figure 3 is a container formed by drawing. Figure 4 is a cross-sectional view of a laminate useful for applications similar to Figure 3, and Figure 5 is a cross-sectional view of a modified laminate useful for applications similar to Figure 3. FIG. 6 is a cross-sectional view of a laminate useful in the manufacture of heat seal lids. 1 is iron or steel foil, 2a12b is a surface treatment layer, 3°3m,
3b is an adhesive layer, 4 is an organic resin inner coating, and 5 is a metal or pigmented organic resin outer coating. Figure 1 Figure 2 Figure 3 Figure 4, Figure 5 Figure 6

Claims (1)

[Claims] (1) A foil substrate made of iron or steel with a thickness of 5 to 120 μm, a surface treatment layer provided on the foil substrate consisting of a metal plating layer or a chromate layer, and an organic resin provided through the surface treatment layer. It is composed of a laminate consisting of a film,
At least one surface of the laminate is provided with an organic resin coating layer having a metal or pigment sufficient to improve processability, to block corrosive components, and to have a concealing effect. A packaging material characterized in that the organic resin coating on the foil substrate has a total thickness of 15 to 200 μm.