JP6650286B2 - Organic resin-coated steel sheet, method for producing the same, and can and can lid using this organic resin-coated steel sheet - Google Patents

Description

  The present invention relates to an organic resin-coated steel sheet having an organic resin layer coated on a substrate via an adhesive layer (primer), a method for producing the same, and a can or can lid using the organic resin-coated steel sheet.

As containers suitable for long-term storage of foods, drinks, pharmaceuticals, etc., so-called two-piece cans (hereinafter also referred to as two-piece cans) having a can body and a lid, and three-piece cans having a can bottom, a can body, and a lid Conventionally, cans of the type (hereinafter also referred to as three-piece cans) have been widely used.
Typically, these cans use a laminate material in which the surface of the substrate is coated with a thermoplastic resin, and in applications where corrosion resistance is required, an additional adhesive layer is provided between the thermoplastic resin and the substrate. It is interposed.

On the other hand, in recent years, there has been an increasing movement to introduce substances that reduce environmental load and to eliminate substances that have an effect on the human body.
For example, as for an adhesive used for a laminate can, development of a material containing no BPA (bisphenol A) has been accelerated due to the movement to eliminate so-called endocrine disrupting substances (for example, see Patent Document 1).
Further, an adhesive which is BPA-free and which can improve processability and corrosion resistance, and a thermoplastic resin-laminated metal plate using this adhesive have been proposed (for example, see Patent Document 2).

JP 2000-319363 A JP 2000-204341 A

As described in Patent Literature 1 and Patent Literature 2, it is essential to be BPA-free in view of social demands, but even in such a case, it is necessary to avoid a decrease in the performance of the can.
In this regard, a steel sheet coated with an organic resin such as a thermoplastic resin is applied to various uses as a container for storing home appliances, vehicles, building materials or foods and beverages, and particularly for storing foods. In applications, retort adhesion is also required.
Although the workability and the corrosion resistance are improved to some extent according to the above-mentioned patent documents, it can be said that there is still room for improvement when the retort adhesion is included. That is, the adhesives described in these patent documents have a problem that the adhesion between the organic resin and the base material is not sufficient, and particularly the adhesion of the can side wall portion when the can is processed is not sufficient. Turned out to be.

  The present invention has been made in view of solving such problems, and has an organic resin-coated steel sheet, a can, and a can lid containing a primer that simultaneously achieves high processing adhesion with an organic resin and retort adhesion without using BPA. , And a method for producing these.

In order to solve the above problems, an organic resin-coated steel sheet according to one embodiment of the present invention includes (1) a base material, an organic resin layer coated on the base material, and the base material and the organic resin layer. Bonding in which a polyester resin and a resole-type phenol resin that do not contain components derived from bisphenols and that are interposed therebetween are contained in a ratio of 5.7 to 19 as a ratio of the polyester resin / the resole-type phenol resin. adhesive layer and, only including, the adhesive layer, the weight ratio to the total weight of the polyester resin and the phenol resin is, as the ratio of the acrylic resin / (the total of the polyester resin and phenol resin), 0. An acrylic resin having a weight ratio of 015 to 0.06 is included .
Further, in the organic resin-coated steel sheet having the above-mentioned feature (1), (2) the polyester resin has a number average molecular weight of 8,000 to 30,000, a glass transition temperature of 50 ° C. or more and less than 85 ° C., and The polyester resin preferably has an acid value of 7 to 15 mgKOH / g.

Further, in the organic resin-coated steel sheet having the features of the above (1) or (2) , ( 3 ) the ratio of the thickness of the adhesive layer to the thickness of the organic resin layer (thickness of the adhesive layer / organic resin layer) Is preferably 3% to 50%.
In addition, in the organic resin-coated steel sheet having any one of the features (1) to ( 3 ), ( 4 ) the organic resin layer is preferably a polyester resin.

Further, in the organic resin-coated steel sheet having any one of the features (1) to ( 4 ),
( 5 ) A surface treatment layer is formed on at least a side of the substrate that contacts the adhesive layer, and the surface treatment layer is made of an oxygen compound containing any of chromium, zirconium, aluminum, and titanium. Is preferred.
Further, in the organic resin-coated steel sheet having the feature of ( 5 ), it is preferable that ( 6 ) the surface treatment layer further contains a phosphorus compound.
The can or can lid of the present invention is formed using an organic resin-coated steel sheet having any one of the features (1) to ( 7 ) described above.

  Further, in order to solve the above problems, the method for producing an organic resin-coated steel sheet according to one embodiment of the present invention is characterized in that the polyester resin and the resole-type phenol resin each containing no component derived from bisphenols are the polyester resin / Forming an adhesive layer containing the resole type phenol resin at a ratio of 5.7 to 19 on at least one surface of the base material or the organic resin layer; A step of forming the organic resin layer on the base material, a step of performing a pre-heat treatment on the base material on which the organic resin layer is formed, in a temperature range of 180 ° C to 280 ° C, And performing a post-heating treatment within a temperature range of 160 ° C. to 240 ° C. on the substrate on which the organic resin layer is formed.

  ADVANTAGE OF THE INVENTION According to this invention, even if it processes to a can without using BPA, the peeling of an organic resin does not generate | occur | produce in a can side wall part, and also can and the can and the can lid excellent in corrosion resistance can be implement | achieved. This makes it possible to simultaneously achieve retort adhesion in addition to high processing adhesion between the organic resin and the metal plate.

It is sectional drawing which showed typically the structure of the organic resin coating steel plate which concerns on this embodiment. FIG. 4 is a process chart showing a production flow of the organic resin-coated steel sheet according to the embodiment. It is sectional drawing regarding the three-piece can which is an example of the container which concerns on this embodiment.

<< 1st Embodiment >>
Hereinafter, embodiments for carrying out the present invention will be described.
As shown in FIG. 1, the organic resin-coated steel sheet 10 according to the present embodiment includes a base material 1, an organic resin layer 4, and an adhesive layer 3 interposed between the base material 1 and the organic resin layer 4. The adhesive layer 3 contains a polyester resin and a resole-type phenol resin each containing no component derived from a bisphenol at a specific ratio (5.7 to 19 as a ratio of polyester resin / resol-type phenol resin). It is characterized by having.
Hereinafter, individual components of the organic resin-coated steel sheet 10 according to the present embodiment will be described in detail.

<Substrate>
As the base material 1 which is a base member of the organic resin-coated steel sheet 10, a metal plate such as iron or various alloys is used.
More specifically, a steel plate of about 0.1 mm to 0.5 mm such as iron or various alloys is used as the metal plate serving as the base material. In the present embodiment, for example, a metal plate made of aluminum as a base material is also suitable.

  Further, as a steel sheet suitable for the present embodiment, for example, a low carbon aluminum killed steel having a carbon amount of 0.01 to 0.15% by mass generally used for cans can also be used. Further, a non-ageing ultra-low carbon aluminum killed steel having a carbon content of less than 0.01% by mass to which niobium or titanium is added is also applicable. The hot-rolled aluminum-killed steel sheet was pickled by electrolytic pickling or the like to remove the scale on the surface, then cold-rolled, and then subjected to electrolytic cleaning, annealing, rolling, etc. to obtain a cold-rolled steel sheet. May be used.

In addition, the surface treatment layer 2 by various surface treatments may be given to the above-mentioned metal plate. That is, the steel plate applicable to the present embodiment includes, for example, a steel plate subjected to various surface treatments such as tinplate, TFS (tin-free steel), and a nickel-plated metal plate.
Such a surface treatment layer 2 may be formed on at least the side of the substrate 1 that is in contact with the adhesive layer 3, and may be formed on both sides of the substrate 1.

The surface treatment layer 2 preferably contains an oxygen compound of zirconium, aluminum or titanium. These oxygen compounds are particularly effective in that they exhibit an effect of improving the adhesive strength between the adhesive layer and the metal plate. The zirconium oxygen compound has a Zr content of 5 to 150 mg / m ² , the aluminum oxygen compound has an Al content of 3 to 50 mg / m ² , and the titanium oxygen compound has a Ti content of 10 mg to 100 mg / m ² . Preferably, there is. The surface treatment layer 2 may include not only a single oxygen compound among these oxygen compounds but also a plurality of oxygen compounds.

The surface treatment layer 2 may further contain a phosphorus compound. The “phosphorus compound” of the present embodiment includes a phosphoric acid compound, and more specifically, phosphoric acid or a salt thereof, condensed phosphoric acid or a salt thereof, zirconium phosphate, titanium phosphate and the like. Examples of the salt include an alkali metal salt such as an ammonium salt, a sodium salt, and a potassium salt. Further, an organosilicon compound may be contained for the purpose of improving adhesion.
The inclusion of such a phosphorus compound in the surface treatment layer 2 is effective in that the effect of further improving the adhesive strength between the adhesive layer and the metal plate is exhibited. In addition, it is preferable that the amount of phosphorus in this phosphorus compound is P amount = 0.1 to 20 mg / m ² .

<Organic resin layer>
The organic resin layer 4 of the present embodiment covers the substrate 1 via an adhesive layer 3 described later. Note that the organic resin layer 4 may cover one or both surfaces of the base material 1 described above.
As such an organic resin layer 4, for example, a thermoplastic resin is suitably used. As examples of the thermoplastic resin that can be used in the present embodiment, various known resins can be applied. For example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acryl Ester copolymers, olefin-based resin films such as ionomers, polyester films such as polyethylene terephthalate and polybutylene terephthalate, unstretched films such as polyvinyl chloride films and polyvinylidene chloride films or biaxially stretched films, or nylon 6, nylon For example, polyamide films such as 6, 6, nylon 11, and nylon 12 can be used.
Among them, a polyethylene terephthalate film is preferable, and isophthalic acid is preferable as the acid component to be copolymerized in this case. However, the acid component is not limited to isophthalic acid, but includes terephthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecandioic acid, and the like.

Further, as the organic resin layer 4, although a non-stretched film is applicable, it is preferable to use a biaxially stretched film. The glass transition temperature (Tg) of the organic resin layer (thermoplastic resin) 4 is preferably 50 to 80 ° C.
Further, these thermoplastic resins (organic resin layer 4) may be coated on the base material 1 via the adhesive layer 3 as one kind of single-layer resin layer, or different organic materials may be blended to form a single-layer resin layer. The substrate 1 may be coated as a resin layer via an adhesive layer, or the substrate 1 may be coated as an at least two kinds of multilayer resin layers via an adhesive layer 3.
When a plurality of thermoplastic resins are used, for example, a polyester resin having an excellent adhesion is selected as the lower layer on the base material 1 side, while the upper layer is excellent in corrosion resistance and non-adsorption of flavor components. May be selected.

The thickness (film thickness) of the organic resin layer 4 is preferably 5 to 40 μm, more preferably 10 to 20 μm. At this time, the thickness ratio of the adhesive layer 3 to the organic resin layer 4 (thickness of the adhesive layer 3 / thickness of the organic resin layer 4) is determined by a seamless can that has undergone a large forming history such as drawing, ironing, and stretching. In a (two-piece can) application, it is desirable that the content be 14 to 50%, more preferably 14 to 40%. Processing may cause residual stress in the can side wall portion of the drawn can, and in particular, a residual stress due to shrinkage of the organic resin layer (thermoplastic resin) occurs in the upper portion of the can side wall portion. For this reason, when the thickness ratio is less than 14%, the shrinkage of the organic resin layer (thermoplastic resin) cannot be suppressed, the adhesion to the organic resin layer (thermoplastic resin) decreases, and peeling tends to occur. On the other hand, if the thickness ratio exceeds 50%, the adhesion to the organic resin layer (thermoplastic resin) and the corrosion resistance are not further improved, and this is disadvantageous in cost.
On the other hand, the adhesive layer 3 may be thinner in a welding can (three-piece can) application or a lid application having a small forming history, and in such a case, the thickness ratio of the adhesive layer 3 to the organic resin layer 4 may be reduced. (Thickness of adhesive layer 3 / thickness of organic resin layer 4) can be 3 to 50%, more preferably 8 to 20%.

<Adhesive layer>
The adhesive layer 3 is interposed between the base material 1 and the organic resin layer 4. For example, in the above-mentioned seamless can application, it is desirable that the thickness of the adhesive layer 3 is in the range of 2 to 10 μm, more preferably 2 to 4 μm. Further, in the above-mentioned welding can use or lid use, the thickness of the adhesive layer 3 can be 0.5 to 6 μm, more preferably 1 to 3 μm.
In the adhesive layer 3 used in the present embodiment, the ratio of the polyester resin to the resol-type phenolic resin is set at a ratio of polyester resin / resol-type phenolic resin from the viewpoint of the balance of resin viscosity, processability, and curability. It is preferably 7 to 19. Further, the ratio of the polyester resin to the resol-type phenol resin is more preferably 10 to 17, and further preferably 14 to 16.
When the amount of the resol-type phenol is less than the above range, the curing of the adhesive becomes insufficient, and as a result, the adhesion and the corrosion resistance are apt to decrease.

On the other hand, when the resol-type phenol is more than the above range, the adhesive layer 3 becomes brittle, and when the organic resin-coated metal plate is processed, the gap between the adhesive layer 3 and the base material 1 or the adhesive layer 3 Separation occurs in the inside, and adhesion and corrosion resistance are likely to decrease. Further, when the adhesive is applied onto the thermoplastic resin, dried, and then wound up, the adhesive may be transferred to a surface on which the adhesive is not applied.
When the phenol resin is a phenol resin other than the resol type, it is difficult to obtain the above-mentioned sufficient adhesiveness.

  The resol-type phenol resin contained in the adhesive layer 3 preferably does not contain a component derived from bisphenols. The resol-type phenol resin contained in the adhesive layer 3 is preferably a copolymer of a phenol compound containing at least 50% by mass of a phenol compound having three or more functional groups and formaldehyde. Examples of the phenol compound include phenol, m-cresol, m-ethylphenol, m-methoxyphenol, xylenol and the like. Further, a phenol compound such as o-cresol, p-cresol, and p-ethylphenol may be added.

  The polyester resin contained in the adhesive layer 3 of the present embodiment is not particularly limited as an acid component. For example, terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, and succinic acid are used as dicarboxylic acid components. Other polycarboxylic acid components such as, for example, glutaric acid, adipic acid, azelaic acid, sebacic acid and dodecandioic acid include trimellitic acid. The glycol component is not particularly limited, but examples thereof include ethylene glycol and propylene glycol, and examples of other polyol components include trimethylolpropane and pentaerythritol.

  The polyester resin contained in the adhesive layer 3 of the present embodiment has a number average molecular weight (Mn) of 8,000 to 30,000, and more preferably 10,000 to 25,000. If the number average molecular weight (Mn) is less than 8,000, the adhesive strength with the organic resin layer 4 is weak, and there is a possibility that the interface peeling between the adhesive layer 3 and the organic resin layer 4 may occur. On the other hand, when the number average molecular weight (Mn) exceeds 30,000, the viscosity becomes high and production may be difficult.

  Further, the glass transition temperature of the polyester resin contained in the adhesive layer 3 of the present embodiment is 50 ° C. or more and less than 85 ° C., and more preferably 50-80 ° C. When the glass transition temperature is lower than 50 ° C., there is a possibility that the thermoplastic resin to which the adhesive has been applied is wound up or blocking occurs with the elapse of time after winding up. On the other hand, when the glass transition temperature exceeds 85 ° C., the elastic modulus near room temperature becomes high, and the resin itself is too hard, so that there is a possibility that the adhesiveness with the thermoplastic resin may not be exhibited.

Further, the acid value of the polyester resin contained in the adhesive layer 3 of the present embodiment is 7 to 15 mgKOH / g, more preferably 8 to 14 mgKOH / g.
Further, an acrylic resin may be added to the adhesive layer 3 of the present embodiment. Such an acrylic resin has an adhesive ratio of 0.015 to 0.06, more preferably 0.02 to 0.04, as a ratio of acrylic resin / (total of polyester resin and phenol resin). Preferably, it is added to layer 3.
The acid value of the acrylic resin is preferably from 0 to 500 (mgKOH / g). If it is 500 or more, the acrylic resin tends to gel. Further, the hydroxyl value is preferably from 0 to 300 (mgKOH / g).
In addition, the acrylic resin used in the present embodiment may be modified with an epoxy group in order to improve mechanical properties, chemical resistance, adhesiveness, and the like.
Monomers that can constitute the acrylic resin include acrylic acid and methacrylic acid; methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate Alkyl (meth) acrylates such as isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, and stearyl (meth) acrylate; Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2,3-dihydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate Monoesters of polyhydric alcohols such as acrylate and polyethylene glycol mono (meth) acrylate with acrylic acid or methacrylic acid; ε-caprolactone adducts of the monoesters; maleic acid, fumaric acid, acrylamide, acrylonitrile, vinyl acetate, Styrene and the like can be exemplified, but not limited thereto.
When an epoxy group is introduced into the acrylic resin, it can be copolymerized with glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, or the like.

<Additives added to adhesive layer>
The adhesive layer 3 may contain various additives for the purpose of improving the concealing property and the corrosion resistance, for example. As such an additive, for example, at least one of titanium oxide, aluminum paste, zinc oxide, organic pigment, and silica can be added to the adhesive layer 3.
In addition, when using titanium oxide as an additive, it is preferable to use a titanium oxide having a particle size of about 0.2 to 0.5 μm.
When an aluminum paste is used as an additive, it is preferable to use an aluminum paste having a particle size of about 3.0 to 15.0 μm.
When zinc oxide is used as an additive, it is preferable to use zinc oxide having a particle size of 0.3 to 1.0 μm.

When an organic pigment is used as an additive, it is preferable to use an organic pigment having a particle size of 0.1 to 1.0 μm.
When silica is used as an additive, it is preferable to use silica having a particle size of about 1.0 to 10.0 μm.
The amount of each of the above specific additives may be appropriately adjusted and set according to the application. If the addition amount is too small, the effect of improving concealing properties and corrosion resistance will be insufficient. If the addition amount is too large, there is a possibility that interfacial peeling between the adhesive layer and the thermoplastic resin and peeling within the adhesive layer may occur.

Further, a wax may be added as an additive. As such a wax, a wax having an addition amount of 0.1 to 3.0% and a melting point of 100 to 130 ° C is preferable. Specific examples of the wax include, for example, polyethylene wax.
Table 1 shows a list of the additives described above.

When a plurality of the above-mentioned materials are added as the above-mentioned additives, it is desirable to add the plurality of additives according to the amount of addition or the ratio of the particle size shown in Table 1. That is, for example, when silica and an organic pigment are added to the adhesive layer 3 as additives, the weight% ratio of the added amount of the silica and the organic pigment is as shown in Table 1, where [silica / organic pigment] is [1/100]. ] To [1/5], respectively. As for the particle size, for example, silica having a particle size shown in Table 1 with respect to the particle size of titanium oxide may be added.
As described above, when a plurality of optional additives are selected from the plurality of additives shown in Table 1, the additives are added to the adhesive layer 3 in accordance with the added amount or the particle size ratio.

Note that the adhesive layer 3 used in the present embodiment may contain an organic solvent.
Such organic solvents include, for example, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, n-hexanol, Alcohols such as cyclohexanol, ketones such as methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone, cyclic ethers such as tetrahydrofuran, dioxane, 1,3-dioxolane, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl Ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol, diethylene glycol Glycol derivatives such as monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol ethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol methyl ether acetate; 3-methoxy-3-methylbutanol; -Methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, cyclohexanone, toluene and the like.

<Production method of organic resin coated steel sheet>
FIG. 2 shows a manufacturing flow of the organic resin-coated steel sheet 10 of the present embodiment.
First, in step 1, the above-described base material is prepared by performing degreasing and / or cleaning treatment as necessary.
Next, in step 2, the above-mentioned surface treatment layer 2 is formed on the base material. Step 2 can be omitted as appropriate.
In step 3, the adhesive is applied to the surface of the organic resin layer 4 (thermoplastic resin) so that the dry film thickness is about 2 to 10 μm, more preferably 2 to 4 μm. Form. Thereafter, drying is performed at a temperature of, for example, 80 to 150 ° C. In step 3, the above-described adhesive was applied to the surface of the organic resin layer 4 (thermoplastic resin). However, the present invention is not limited to this, and the adhesive may be applied to the base material 1 (or the surface treatment layer 2). Then, an adhesive may be applied to both the organic resin layer 4 side and the substrate 1 side.

  Next, in step 4, by laminating the organic resin layer 4 (thermoplastic resin) on which the adhesive layer 3 is formed in step 3 to the substrate 1, the organic resin-coated steel sheet 10 of the present embodiment is produced. . At this time, the surface treatment layer 2 may be formed on the substrate 1. The temperature of the substrate 1 during lamination as preheating is preferably 180 to 280 ° C.

  In Step 4, the adhesion between the substrate 1 and the organic resin layer 4 (thermoplastic resin) is further raised by performing a heat treatment (post-heating) on the organic resin-coated metal plate obtained by lamination. be able to. The method of the heat treatment as such post-heating is not particularly limited. Further, the heat treatment temperature for the subsequent heating is 160 to 240 ° C., more preferably 170 to 210 ° C., as the temperature of the substrate 1.

If the temperature by post-heating is lower than 160 ° C., sufficient adhesion cannot be obtained within the heat treatment time of 3 to 30 minutes. On the other hand, when the temperature due to the post-heating exceeds 240 ° C., the heat shrinkage of the biaxially stretched polyester film becomes large, and the film tends to peel off at the end of the organic resin-coated metal plate after the heat treatment.
The heat treatment time required for the post-heating is 3 to 30 minutes, more preferably 5 to 20 minutes. If the heat treatment time is less than 3 minutes, sufficient adhesion cannot be obtained. On the other hand, if the heat treatment time exceeds 30 minutes, the adhesive layer 3 is easily broken at the time of processing such as can making.

<Container>
FIG. 3 shows a container C manufactured using the organic resin-coated steel sheet 10.
The container C of the present embodiment is obtained by coating the base material 1 with the organic resin 2 via the adhesive layer 3 to obtain the organic resin-coated steel sheet 10, and then drawing, drawing and redrawing, stretching draw forming, It can be produced by performing various moldings such as stretch ironing molding and drawing and ironing molding.
FIG. 3 shows a seamless can using the organic resin-coated metal plate of the present embodiment. FIG. 1 shows an example in which the surface treatment layer 2, the adhesive layer 3, and the organic resin layer (thermoplastic resin) 4 are coated on the inner surface side of the seamless can. Various known films may be formed. Alternatively, the outer surface side of the seamless can may be coated with the above-described surface treatment layer 2, adhesive layer 3, and organic resin layer (thermoplastic resin) 4. Further, the organic resin-coated metal plate of the present invention can be applied to a three-piece can such as a welded can in addition to a seamless can.
Further, the organic resin-coated steel sheet 10 obtained according to the present embodiment can also be used as the can lid Cp shown in FIG. 3, and the above-mentioned “container” includes a can lid that functions as a part of the container. Shall be. The structure of the can lid is not particularly limited, and examples thereof include a flat lid and an easy-open can lid.

In the case of a can lid to which the present embodiment is applied, the organic resin layer 4 is preferably a coating film in addition to the above-described thermoplastic resin. Examples of such coatings include thermosetting resin paints such as phenol-formaldehyde resins, furan-formaldehyde resins, xylene-formaldehyde resins, ketone-formaldehyde resins, urea-formaldehyde resins, melamine-formaldehyde resins, alkyd resins, and unsaturated resins. Polyester resin, epoxy resin, bismaleimide resin, triallyl cyanurate resin, thermosetting acrylic resin, silicone resin, oily resin, or thermoplastic resin paint such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate Partially saponified polymers, vinyl chloride-maleic acid copolymers, vinyl chloride-maleic acid-vinyl acetate copolymers, acrylic polymers, saturated polyester resins and the like can be mentioned. These resin coatings may be used alone or in combination of two or more. Among these, epoxy acrylic paints, epoxy phenol paints, polyester paints, epoxy urea paints, vinyl organosol paints and the like are preferred.
In addition, since the adhesive layer of the organic resin-coated steel sheet of the present invention does not contain a component derived from bisphenols, even when the organic resin layer 4 is formed of a coating film, a paint containing no component derived from bisphenols is selected. Is preferred.

<Example>
Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.
First, evaluation or measurement modes of each characteristic in Examples, Comparative Examples, and Reference Examples described later will be described.

<Method of measuring thickness (film thickness) of adhesive layer 3>
The substrate 1 of the organic resin-coated metal plate was dissolved with sulfuric acid, and isolated into only the organic resin layer (thermoplastic resin) 4 and the adhesive layer 3. Thereafter, the sample was embedded in a resin to perform an embedding process, and then sliced in a thickness direction with a microtome to prepare a sample having a thickness of 3 μm. The sample was set on a transmission optical microscope, and polarized light was applied to distinguish the organic resin layer (thermoplastic resin) 4 from the adhesive layer 3 and measure the thickness of the adhesive layer 3.

<Method of evaluating adhesion to thermoplastic resin>
The adhesion of the organic resin-coated metal plate was evaluated on a flat plate and a can side wall portion of a drawn can, respectively. Further, the same method was used after the retort treatment. The retort treatment was performed at 125 ° C. for 30 minutes in a state where the test piece was immersed in water.
As a specific evaluation, a checkerboard having a depth reaching the metal plate at an interval of 5 mm was inserted into the organic resin-coated metal plate, peeled off with a tape, and the degree of peeling was visually observed and evaluated.

The evaluation of adhesion was performed according to the following criteria. The evaluation of adhesion was performed for all Examples and Comparative Examples described later.
[Evaluation criteria for adhesion]
A: No peeling of the thermoplastic resin was observed as a result of the visual judgment.
：: As a result of visual judgment, slight peeling of the thermoplastic resin was recognized although it could be put to practical use.
B: As a result of visual judgment, peeling of the thermoplastic resin was recognized at an area ratio of 1/5 or less.
X: As a result of visual judgment, peeling of the thermoplastic resin was observed at an area ratio exceeding 1/5.
In the evaluation of adhesiveness, when the evaluation was ◎ or で according to the above criteria, it was determined that the film had sufficient adhesiveness when used for food and drink cans.

<Evaluation method on the side wall of the can>
After the paraffin wax was applied to the organic resin-coated metal plate, the blank was punched into a blank having a diameter of 160 mm, and then subjected to drawing twice, to obtain a molded can having a drawing ratio of 1.8, a height of 50 mm, and a diameter of 90 mm.
Then, the side wall portion of the draw-formed can is cut out to a size of 50 mm × 60 mm, and a curve is forcibly applied. Then, grids having a depth reaching the metal plate are inserted at intervals of 5 mm, peeled off with a tape, and the degree of peeling is visually observed. Observed and evaluated.

The evaluation of the adhesion at the side wall of the can was performed according to the following criteria. This adhesion evaluation was performed for all Examples and Comparative Examples described later.
[Evaluation criteria for adhesion on the side wall of the can]
A: No peeling of the thermoplastic resin was observed as a result of the visual judgment.
：: As a result of visual judgment, slight peeling of the thermoplastic resin was recognized although it could be put to practical use.
B: As a result of visual judgment, peeling of the thermoplastic resin was recognized at an area ratio of 1/5 or less.
X: As a result of visual judgment, peeling of the thermoplastic resin was observed at an area ratio exceeding 1/5.
In the evaluation of adhesiveness, when the evaluation was ◎ or で according to the above criteria, it was determined that the film had sufficient adhesiveness when used for food and drink cans.

<Evaluation of content filling (pack test)>
After punching an organic resin-coated metal plate into a circular blank, drawing is performed twice, bottom panel processing, bead processing, and trimming processing are performed. The inner diameter of the can is 83.2 mm, the height of the can is 44.1 mm, and the inner volume is 213 ml. A drawn can was formed.
After filling the obtained squeezed can with the contents, the aluminum easy-open lid was double-tightened and then retorted.
The contents were pickled in tuna oil, boiled in tuna water, and boiled in tuna soy sauce, and the quality retention (appearance, pH, taste) of the contents after 3 months at 37 ° C. was evaluated.

The pack test was evaluated based on the following criteria.
[Evaluation criteria for pack test]
：: equivalent to Reference Example 1 △: Compared to Reference Example 1, the contents were slightly discolored or the taste was changed.
×: The content was discolored or the taste was changed as compared with Reference Example 1.
In addition, when the quality retention was equivalent to that of Reference Example 1, it was determined that there was practicality.

<Example 1>
The adhesive A shown in Table 2 was applied to a thermoplastic resin (biaxially stretched polyester film) having a thickness of 12 μm using a gravure coater and dried at 100 ° C. At that time, the applied amount of the adhesive was 20 mg / dm ² , and the thickness after drying was 2 μm. At this time, the thickness of the adhesive / the thickness of the thermoplastic resin was 17%.
The base material is a cold-rolled steel sheet of low carbon aluminum killed steel with a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an alkaline aqueous solution, washed with water, further washed with sulfuric acid and water, and then subjected to electrolytic treatment. the metallic chromium amount 100 mg / ^{m 2,} to form a chromium plating layer of chromium hydroxide 15 mg / ^{m 2,} to prepare a TFS.

Next, the surface-treated metal plate was heated to 240 ° C., and the thermoplastic resin was thermocompression-bonded to both sides of the surface-treated metal plate using a laminating roll, and immediately cooled with water to form an organic resin-coated metal plate. .
The obtained organic resin-coated metal plate was heated at 180 ° C. for 5 minutes, and then the adhesion was evaluated according to the method described above. Table 3 shows the results.

<Example 2>
The procedure was performed in the same manner as in Example 1 except that the heat treatment temperature of the organic resin-coated metal plate was changed to 10 minutes. Table 3 shows the results.

<Example 3>
The same operation as in Example 1 was performed except that the thickness of the adhesive was 3 μm. Table 3 shows the results.

<Example 4>
The procedure was performed in the same manner as in Example 3, except that the heat treatment temperature of the organic resin-coated metal plate was changed to 10 minutes. Table 3 shows the results.

<Example 5>
The procedure was performed in the same manner as in Example 1 except that the thickness of the adhesive was changed to 4 μm. Table 3 shows the results.

<Example 6>
The procedure was performed in the same manner as in Example 5, except that the heat treatment temperature of the organic resin-coated metal plate was changed to 10 minutes. Table 3 shows the results.

<Example 7>
Example 4 was carried out in the same manner as in Example 4 except that the thickness of the thermoplastic resin was 19 µm, the surface-treated metal plate was heated to 260 ° C, and the thermoplastic resin was thermocompressed. Table 3 shows the results.

<Example 8>
The same operation as in Example 7 was performed except that the thickness of the adhesive was 4 μm. Table 3 shows the results.

<Example 9>
The base material is a cold-rolled steel sheet of low carbon aluminum killed steel with a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an alkaline aqueous solution, washed with water, further washed with sulfuric acid and water, and then subjected to electrolytic treatment. To form a Sn plating layer having an Sn amount of 2.8 g / m ² , performing a reflow treatment (fused molten tin treatment), and then forming a Cr oxygen compound layer having a Cr amount of 5 mg / m ² by electrolytic treatment. Was used. The components of the adhesive were adhesive B shown in Table 2, the surface-treated metal plate was heated to 220 ° C., and the thermoplastic resin was thermocompressed. Other than that, it carried out similarly to Example 6. Table 3 shows the results.

<Example 10>
The base material is a cold-rolled steel sheet of low carbon aluminum killed steel having a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an aqueous alkaline solution, washed with water, and further washed with sulfuric acid and water, followed by electrolytic treatment. Example 2 was carried out in the same manner as in Example 2 except that a Zr oxygen compound layer having a Zr amount of 100 mg / m ² was formed. For the electrolytic treatment, a treatment solution having a pH of 3.0 containing zirconium ammonium fluoride as a main component was used. Table 3 shows the results.

<Example 11>
The base material is a cold-rolled steel sheet of low carbon aluminum killed steel with a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an alkaline aqueous solution, washed with water, further washed with sulfuric acid and water, and then subjected to electrolytic treatment. To form an Sn plating layer having an Sn amount of 2.8 g / m ² , performing a reflow treatment (fused tin treatment), and then forming an Al hydroxide layer having an Al amount of 5 mg / m ² by electrolytic treatment. Tinplate was used. Other than that, it carried out similarly to Example 2. Table 3 shows the results.

<Example 12>
The procedure was performed in the same manner as in Example 2 except that the components of the adhesive were changed to Adhesive C shown in Table 2. Table 3 shows the results.

<Example 13>
The procedure was performed in the same manner as in Example 2 except that the components of the adhesive were changed to Adhesive D shown in Table 2. Table 3 shows the results.

  As shown in Table 3, the ratio of the polyester resin and the resol-type phenol resin in which the components of the adhesive do not include the components derived from bisphenols is 5.7 to 19%, and the ratio of the thickness of the adhesive to the thickness of the thermoplastic resin (thickness of the adhesive / thickness of the thermoplastic resin) is 14% to 50%. It was shown that the plate had sufficient adhesiveness and had sufficient adhesiveness even after retort treatment. Further, good results were obtained even when the surface of the metal plate had a surface treatment layer, and the surface treatment layer was made of any one of oxygen compounds of zirconium, aluminum and titanium.

<Example 14>
The procedure of Example 4 was repeated except that the components of the adhesive were as shown in Table 2, and the surface-treated metal plate was heated to 260 ° C. and the thermoplastic resin was thermocompressed. Table 3 shows the results.

<Example 15>
Example 14 was carried out in the same manner as in Example 14 except that the components of the adhesive were changed to the adhesive G shown in Table 2. Table 3 shows the results.

<Example 16>
Example 14 was carried out in the same manner as in Example 14, except that the components of the adhesive were adhesive H shown in Table 2. Table 3 shows the results.

<Example 17>
The adhesive A shown in Table 2 was applied to a thermoplastic resin (biaxially stretched polyester film) having a thickness of 12 μm using a gravure coater and dried at 100 ° C. At that time, the applied amount of the adhesive was 30 mg / dm ² , and the thickness after drying was 3 μm. At this time, the thickness of the adhesive / the thickness of the thermoplastic resin was 25%.
The base material is a cold-rolled metal sheet of low carbon aluminum killed steel with a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an aqueous alkaline solution, washed with water, further washed with sulfuric acid and water, and then subjected to electrolytic treatment. metallic chromium amount 100 mg / ^{m 2} by the processing, to form a chromium plating layer of chromium hydroxide 15 mg / ^{m 2,} to prepare a TFS.

Next, the surface-treated metal plate was heated to 240 ° C., and the thermoplastic resin was thermocompression-bonded to both sides of the surface-treated metal plate using a laminating roll, and immediately cooled with water to form an organic resin-coated metal plate. .
The obtained organic resin-coated metal plate was heated at 180 ° C. for 10 minutes, and then a drawn can was manufactured according to the method described above. Thereafter, the contents were filled, and after a lapse of time, the quality retention was evaluated. Table 4 shows the results.

<Example 18>
The same operation as in Example 14 was performed except that the thickness of the thermoplastic resin was changed to 19 μm. Table 4 shows the results.

In Examples 19 to 23 shown below, only the evaluation of a flat plate was performed mainly assuming application to a can lid.
<Example 19>
The same procedure as in Example 2 was carried out except that the components of the adhesive were adhesive J shown in Table 2 and the application amount was 10 mg / dm ² . Table 5 shows the results.

<Example 20>
The same operation as in Example 2 was performed except that the amount of the adhesive applied was 10 mg / dm ² . Table 5 shows the results.

<Example 21>
The same procedure as in Example 2 was performed except that the amount of the adhesive applied was 50 mg / dm ² . Table 5 shows the results.

<Example 22>
The same procedure as in Example 2 was performed except that the amount of the adhesive applied was 3 mg / dm ² . Table 5 shows the results.

<Example 23>
Example 2 was repeated except that the amount of the adhesive applied was 70 mg / dm ² . Table 5 shows the results.

<Comparative Example 1>
The components of the adhesive were adhesive I shown in Table 2, the thickness of the adhesive was 1.5 μm, the surface-treated metal plate was heated to 260 ° C., and the thermoplastic resin was thermocompressed. Other than that, it carried out similarly to Example 1. Table 3 shows the results.

<Comparative Example 2>
The procedure was performed in the same manner as in Comparative Example 1 except that the thickness of the thermoplastic resin was 19 μm, the thickness of the adhesive was 2 μm, and the heat treatment temperature of the organic resin-coated metal plate was 5 minutes. Table 3 shows the results.

<Comparative Example 3>
The procedure was performed in the same manner as in Comparative Example 2 except that the heat treatment temperature of the organic resin-coated metal plate was changed to 10 minutes. Table 3 shows the results.

<Comparative Example 4>
The procedure was performed in the same manner as in Comparative Example 1 except that the thickness of the thermoplastic resin was 19 μm and the thickness of the adhesive was 2.5 μm. Table 3 shows the results.

<Comparative Example 5>
The same procedures as in Example 11 were carried out except that the components of the adhesive were adhesive E shown in Table 2 and the thickness of the adhesive was 3 μm. Table 3 shows the results.

<Comparative Example 6>
Example 14 was repeated except that the composition of the adhesive was epoxy phenol and the thickness of the adhesive was 1 μm. Table 4 shows the results.

<Reference Example 1>
The base material is a cold-rolled steel sheet of low carbon aluminum killed steel with a thickness of 0.16 mm. This metal sheet is electrolytically degreased in an alkaline aqueous solution, washed with water, further washed with sulfuric acid and water, and then subjected to electrolytic treatment. the metallic chromium amount 100 mg / ^{m 2,} to form a chromium plating layer of chromium hydroxide 15 mg / ^{m 2,} to prepare a TFS.
After heat-treating the surface-treated metal plate at a temperature of 190 ° C. for 10 minutes, an epoxyphenol-based paint is applied so that the coating thickness after baking and drying is 70 mg / dm ^2, and then at a temperature of 200 ° C. for 10 minutes. Was obtained to obtain an organic resin-coated metal plate. Next, a welding can having the same capacity as in Example 13 was produced. Thereafter, the contents were filled, and after a lapse of time, the quality retention was evaluated. Reference Example 1 corresponds to a product currently on the market. Table 4 shows the results.

  As shown in Table 4, the organic resin-coated metal plate obtained according to the present invention was as good in quality retention as in Reference Example 1 in all contents. Note that Comparative Example 9 is equivalent to a commercially available product, but is not applied to some contents such as boiled tuna and boiled tuna soy because the properties are inferior to those of Reference Example 1. Therefore, it is judged that the organic resin-coated metal plate obtained by the present invention has more practical suitability than the conventional product.

As is clear from the above, in each of the examples of the present invention, the processing adhesion, the retort adhesion and the quality retention were all good.
The above-described embodiment and each example can be variously modified without departing from the spirit of the present invention.

  As described above, the organic resin-coated steel sheet of the present invention and containers using the same, such as cans and can lids, have high levels of adhesion and quality retention at the same time without using BPA. It can be applied to industry.

DESCRIPTION OF SYMBOLS 1 Base material 2 Surface treatment layer 3 Adhesive layer 4 Organic resin layer 10 Organic resin-coated steel plate C Container Cp Can lid

Claims (9)

A substrate,
An organic resin layer coated on the base material,
A polyester resin and a resole-type phenol resin which are interposed between the base material and the organic resin layer and do not contain a component derived from bisphenols respectively have a ratio of the polyester resin / the resole-type phenol resin of 5.7. an adhesive layer formed by a proportion of to 19, only including,
The adhesive layer,
The weight ratio to the total weight of the polyester resin and the phenol resin includes an acrylic resin having a weight ratio of 0.015 to 0.06 as a ratio of acrylic resin / (total of polyester resin and phenol resin). An organic resin-coated steel sheet characterized by the above-mentioned.   The organic resin according to claim 1, wherein the polyester resin has a number average molecular weight of 8000 to 30,000, a glass transition temperature of 50 ° C or more and less than 85 ° C, and an acid value of the polyester resin of 7 to 15 mgKOH / g. Coated steel sheet. The ratio of the thickness of the adhesive layer and the organic resin layer (thicknesses of / organic resin layer of the adhesive layer), an organic resin-coated steel sheet according to claim 1 or 2 is 3% to 50%. The organic resin-coated metal plate according to any one of claims 1 to 3 , wherein the organic resin layer is a polyester resin. A surface treatment layer is formed on at least a side of the base material that is in contact with the adhesive layer,
The organic resin-coated steel sheet according to any one of claims 1 to 4 , wherein the surface treatment layer is made of an oxygen compound containing any one of chromium, zirconium, aluminum, and titanium. The organic resin-coated steel sheet according to claim 5 , wherein the surface treatment layer further contains a phosphorus compound. A can using the organic resin-coated metal plate according to any one of claims 1 to 6 . A can lid using the organic resin-coated metal plate according to any one of claims 1 to 6 . An adhesive layer containing a polyester resin and a resol-type phenol resin each containing no component derived from bisphenols in a ratio of 5.7 to 19 as the ratio of the polyester resin / the resol-type phenol resin is used as a base material. Or a step of forming on at least one surface of the organic resin layer,
Forming the organic resin layer on the base material such that the adhesive layer is interposed,
Performing a pre-heating treatment on the substrate on which the organic resin layer is formed in a temperature range of 180 ° C to 280 ° C;
After the pre-heating treatment, a step of performing a post-heating treatment on the substrate on which the organic resin layer is formed within a temperature range of 160 ° C to 240 ° C,
A method for producing an organic resin-coated steel sheet, comprising: