JPS6250319B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a metallized hot stamping foil, that is, a resin layer containing a metallized film formed on a carrier film by applying heat and pressure. This invention relates to improvements in transfer foils (hereinafter referred to as hot stamping foils) for transferring transfer layers onto objects.

In recent years, among hot stamping foils, metal-deposited so-called metallic stamping foils have been used in place of wet metal plating for home appliances and automobile parts, due to their non-polluting properties.
It has been widely used because of the simplicity and ease of equipment and process for users, and the ability to freely select patterns, but it does not necessarily mean that there are no problems in the performance of the hot stamping process and the transfer material after transfer. do not have. Generally, these hot stamping foils consist of at least three layers: a protective layer consisting of an organic polymeric resin layer and a similar adhesive, interposed in between a vacuum-deposited metal film, i.e., a layer made of metal and resin. Due to the complex structure, there were various areas of disharmony.
In particular, the hot stamping foil first comprises:
Due to the application of fairly high heat and especially large pressure when transferring to a plastic molded substrate using injection molding, cracks, so-called burns, whitening, discoloration, peeling, and cleavage are likely to occur during the stamping process. Although this depends on the performance of the protective layer and the adhesive layer itself, it is not always possible to satisfy the compatibility with the vapor-deposited metal layer at the same time due to the unique performance required for the protective layer and the adhesive layer. It also depends on what isn't there. That is, the protective layer is
In order to be exposed on the surface after transfer, chemical resistance, abrasion resistance, hardness, heat resistance, etc. are required, and the adhesive layer must first have hot melt-like adhesion to the target transfer substrate. Therefore, the more these basic characteristics are improved and enhanced, the more difficult it becomes to achieve harmony with the deposited metal layer. In particular, recently, not only conventional aluminum but also metals such as chromium, nickel, iron, or alloys based on these have begun to be used as vapor-deposited metals, mainly for exterior applications, so the deposition process has become more difficult than aluminum. It is becoming difficult to maintain a balance between membranes, thermal properties, and membrane properties such as expansion, contraction, ductility, and mechanical relaxation. The present invention provides a hot stamping foil having a useful matching layer between these metallized films.

In a hot stamping foil having been subjected to metal vapor deposition, the present invention provides a resin having the following composition, which is placed in direct contact with the vapor-deposited metal film before and/or after the metal vapor deposition, that is, (a) At least one basic nitrogen-containing acrylic monomer 0.2 to 30% by weight (b) Acrylic acid or methacrylic acid and aliphatic 1
At least one ester with a alcohol
35 to 99.8% by weight and (c) an acrylic monomer having a group selected from a carboxyl group, a hydroxyl group, a glycidyl group, a nitrile group and an amide group; a carboxyl group,
A methacrylic monomer having a group selected from a hydroxy group, a glycidyl group, a nitrile group, and an amide group; 0 to 60% by weight of a monomer selected from styrene; α-methylstyrene; vinyltoluene and vinyl acetate. A coating film is formed in which the main resin component is a resin blended with an acrylic copolymer () as a copolymerization component and a compound or polymer () having two or more epoxy groups per molecule. It includes the configuration as essential.

The basic structure of a hot stamping foil is generally as shown in FIG. 1b.

First, as the carrier layer 1, a biaxially stretched polyethylene terephthalate film is generally preferred from the viewpoint of heat resistance, dimensional stability, toughness, etc. Similarly, a biaxially stretched polypropylene film or the like may be used, but is not limited thereto. Needless to say. The thickness is between 6 and 50 microns, especially
It is preferably about 12 to 25 microns. Further, it is also possible to previously apply matte processing, hairline processing, etc. to these carrier films.

Various release agent layers 2 are applied onto these carrier films by various known methods such as gravure coating, reverse roll coating, and natural coating. If it can be separated smoothly, it may be omitted. As these mold release agents, cellulose, silicone, hydrocarbon wax, acrylic resin, phospholipid, etc. can be used singly or in combination, but of course the mold release agent is not limited to these.
The thickness of the release layer is usually preferably about 0.05 to 0.5 microns.

On this mold release layer 2, a protective layer 3 is similarly applied. For the protective layer, resins are used that meet various required characteristics. For example, acrylic resin,
Examples include melamine resin, phenolic resin, DAP resin, polyester resin, and epoxy resin.

These are similarly applied by various known coating methods, but gravure coating, reverse coating, doctor knife coating, etc. are often used. However, it is not necessarily limited to these. These are usually coated to a fixed thickness of about 2 to 10 microns.

It is simple and conventional in terms of the number of steps to directly vacuum deposit aluminum, generally directly on the protective layer, and then directly coat an adhesive layer on the vacuum deposited metal layer. It has been generally adopted.

However, for the various reasons mentioned above, it was found that products of higher quality and performance could not be produced using this method alone, leading to the present invention. That is, in the present invention, before and/or after the vacuum deposition of these metals, a coating film mainly composed of a resin having the composition () and () above is formed.

In the present invention, component (a) of the acrylic copolymer () includes dimethylaminoethyl acrylate or methacrylate, diethylaminoethyl acrylate or methacrylate, t-
Acrylic acid and/or methacrylic acid derivatives such as butylaminoethyl acrylate or methacrylate are preferably used, but other N-
Acrylamide or methacrylamide derivatives such as dimethylaminoethyl acrylamide or methacrylamide, N-diethylaminoethyl acrylamide or methacrylamide can also be used. The amount of these used is 0.2 to 30% by weight, and a range of 0.5 to 15% by weight is particularly preferred from the viewpoint of performance and cost.

As component (b) of said (), esters of acrylic acid or methacrylic acid and acyclic or cyclic aliphatic monohydric alcohols are suitable, especially methanol, ethanol, propanol, butanol, lauryl alcohol, stearyl Esters and the like with alcohols etc., and mixtures thereof are preferred, and 35 to 99.8%, preferably 50 to 80% by weight of the polymeric monomers are used.

As component (c) of said (), styrene and a small amount of acrylic acid and/or methacrylic acid are particularly preferably used, but in addition, α-methylstyrene, vinyltoluene, acrylonitrile, vinyl acetate, 2-hydroxyethyl acrylate or Any monomer included in the above definition may be used, such as methacrylate, 2-hydroxypropyl acrylate or methacrylate, acrylamide or methacrylamide, methylol compounds thereof, itaconic acid, glycidyl acrylate or methacrylate, and the amount used is , 0 to 60% by weight, preferably 20 to 45% by weight.

Although any polymerization method can be used to polymerize the above-mentioned acrylic copolymer (2), solution radical polymerization is particularly preferred. That is, a polymerization initiator such as an azobis-based and/or peroxide-based initiator is used in the presence of an aromatic solvent such as toluene, and/or an alcoholic solvent such as isobutanol, and/or an ester solvent such as ethyl acetate. However, by the usual method,
Can be preferably polymerized. Further, in order to control the degree of polymerization, it is possible to use various chain transfer agents in combination. As mentioned above, the acrylic copolymer () contains component (a)
It is considered preferable that component (b) and component (c) are both copolymerized, but for example, component
A copolymer of component (a) and a part of component (b), or a copolymer of component (a) and a part of component (c).
Alternatively, two or more components (b) and (c) may be polymerized separately and then mixed together afterwards.

Next, as the compound or polymer () having two or more epoxy groups per molecule, compounds or polymers well known as polyepoxides are appropriately used, and glycidyl ethers of polyhydric alcohols are particularly preferably used. That is, ethylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, sorbinol polyglycidyl ether, etc. are preferably used.

The blending ratio of the acrylic copolymer () and these epoxy compounds or epoxy resins () is: basic nitrogen atom (gram atom) in the acrylic copolymer ()/epoxy group in the epoxy compound or resin (). Oxygen atoms (gram atoms) are preferably about 0.5 to 3, but are not necessarily limited to this.

In the present invention, it is necessary that the resin consisting of the combination of () and () be the main component of the resin itself of the coating layer that is in direct contact with the vapor-deposited metal layer. That is, the specific gravity of the main component is 70% by weight or more, more preferably 90% by weight or more of the resin content of the coating layer. In addition to these resins themselves, various pigments and additives may be included. These are added and their amounts can be adjusted up or down as appropriate depending on various minute quality requirements at the time. In addition, the inclusion of various other resins in the resin can be selected as appropriate, for example, to provide better adhesion, flexibility, or hardness. However, in general, when used as in the present invention, since the layer is thin and the resin compound of the present invention has very good adhesion, it can be said that it is not really necessary.

The formulation of resins centered on the above () and () is made by mixing an acrylic polymer () dissolved in a thinner such as toluene or alcohol, and an epoxy compound or resin (), preferably just before coating. It is preferable to apply without leaving it for a long time.

These paints are applied as organic solvent solutions with a total solids content of several percent to 10 percent at most, using methods such as gravure roll coating, reverse roll coating, and natural roll coating, but are not necessarily limited to these methods. Not even. The thickness thereof is preferably about 0.05 to 3 microns, particularly preferably about 0.1 to 1.0 microns, but this is not necessarily limited to these as well.

The compounded resin of the present invention is coated on the protective layer 3 to form a coating layer 6, and then a metal vapor deposited layer 4 is formed in direct contact with the coating layer 6, as shown in FIG. 1b. Alternatively, the coating layer 6 may be omitted and the metal vapor deposited layer 4 may be formed directly on the protective layer 3.
After forming, the compound layer of the present invention may be formed thereon as a coating layer 7 so as to be in direct contact with the metal vapor deposited layer.Furthermore, after forming the coat layer 6, directly metal vapor deposition may be performed. Similarly, the blended resin coating layer 7 of the present invention may also be formed by coating it so as to be in direct contact with the metal vapor deposited layer.

The present invention is particularly effective in the case of ordinary thermal evaporation of aluminum, both before and after the metal evaporation layer, but in the case of chromium, nickel, iron, and their alloys, it is necessary to form a coating after the metal evaporation. In these cases, the effect of the present invention is more pronounced than in the case of aluminum. The reason for this is not necessarily clear, but the film of aluminum itself is highly flexible (therefore, it is too soft and is not suitable for hot stamping foils that require hardness and wear resistance, and it also has poor corrosion resistance. Although the conventional techniques are effective to some extent, other hard corrosion-resistant metals are considered to have disadvantages. However, on the contrary, these corrosion-resistant metals with high melting points have good adhesion during vapor deposition, and in that sense, it can be said that there is little necessity to use the compounded resin of the present invention before vapor deposition, but after vapor deposition, , the difference between its use and non-use is remarkable. In other words, these vapor-deposited metal layers have no affinity with the adhesive layer 5 shown in FIG. Problems arise in terms of ease of use. In this sense, it is better to form the blended resins () and () of the present invention as the coating layer 7 interposed between the adhesive layer 5 and the adhesive layer 5 after forming the high melting point/corrosion resistant metal vapor deposition layer 4. It is valid.

In addition, this effectiveness is due to the fact that the high melting point and corrosion resistant metal layer
It is more effective when formed by sputtering.

Furthermore, the protective layer 3 has the following composition: (a) 2 to 20% by weight of at least one of acrylic acid, methacrylic acid, or itaconic acid (b) acrylic ester of polyhydric alcohol or methacrylic ester of polyhydric alcohol (c) At least one of acrylamide, methacrylamide or their derivatives 0.5-20% by weight (d) At least one of the above (a), (b) and (c) A composition in which an acrylic copolymer containing 20 to 80% by weight of a polymerizable monomer is blended with a melamine resin at a ratio of 90/10 to 40/60 (weight ratio) is at least the resin component. In the case of the protective layer 3 consisting of a resin containing 80% and additives added as appropriate, this is extremely good as a protective layer itself, and on top of this, a blended resin layer of () and () of the present invention is applied. ,
It is effective to form the coating layer 6 of FIG. 1b and then sputter and vapor-deposit these high-melting-point corrosion-resistant metals. However, a more detailed analysis shows that even if this coat layer 6 is omitted,
Next to the sputtering vapor deposited layer 4 is an intervening coating layer 7.
Therefore, it is more effective to form the adhesive layer 5 after forming the blended resin layer of () and () of the present invention.

In addition, the thickness of the above-mentioned vapor-deposited metal layer is generally 100~
The thickness is preferably 1000 Å, particularly 150 to 600 Å, but is not necessarily limited thereto.

As mentioned above, the blended resins () and () of the present invention are generally used as a solution in an organic solvent and applied.
It is carried out at ~200°C, preferably 120-180°C, for 0.5-5 minutes, preferably around 1 minute. The blended resin of the present invention has the property of curing even at a temperature lower than the above, for example, at room temperature. However, in view of problems such as blocking and harmful effects of residual solvents and unreacted residues, it is preferable to carry out the drying/crosslinking reaction and curing at medium to high temperatures and times as described above. In this way preferably () and () of the invention
After forming the blended resin layer 7, various types of hot stamping foil resins are used as the adhesive layer 5 to be coated, that is, mainly thermoplastic resins that flow with heat and exhibit adhesive properties. Examples include, but are not limited to, polymethacrylic resins, rosin-modified maleic acid resins, and polyester resins. In addition, the solid content thickness of these products is generally about 1 to 5 microns, using a gravure roll coater, reverse roll coater,
It is generally coated with a solution using a natural coater, doctor knife coater, etc.
Similarly, it is not necessarily limited to these.

The hot stamping foil b (Fig. 1) produced in this way is placed on a molded product 9 (Fig. 1) made of various types of plastic, etc.
As shown in Fig. 2, heat and pressure are applied from the carrier film side of the hot stamping foil b to stamp the molded part 9 in a pattern over the necessary protrusions, etc. or, if necessary, on a flat surface. The entire surface of the molded product is stamped, and the carrier film 1 is peeled off and removed.

The characteristics of using the blended resin composition of the acrylic copolymer () and polyepoxide () of the present invention are as follows:
This is because polyepoxide is used as a crosslinking agent in the crosslinking reaction of certain acrylic resin paints.
One reason is that it has an affinity with the vapor-deposited metal layer and has good adhesion, but even though it is thin, it is relatively strong and heat resistant. It is not very strong and has good foil cutting properties, and another great feature is that it is generally compatible with other resin layers, such as the protective resin layer 3 and the adhesive resin layer 5, and as a whole foil, especially among metals. Metal films such as chromium, nickel, iron, and alloy-based metal deposits containing at least one of these as their main components are hard and have little malleability, that is, they tend to crack or whiten even with the slightest strain, and they are difficult to mechanically adhere to.・They are thermally compatible. Therefore, during the stamping process, in order to increase transfer productivity as much as possible, even if the transfer temperature is increased and hot stamping is performed at a high speed cycle, the transfer film will not become burnt due to the pressure and temperature, such as whitening or discoloration. It has the characteristic of being able to be smoothly transferred without causing cracks or cracks in the resin layer and vapor-deposited metal film, and without peeling or cleavage between the layers. Furthermore, the peelability of the transfer film layer from the carrier film (foil separation property) is also good, and in particular, the patterned foil cutting property is also improved.

Of course, these characteristics depend on the protective layer and adhesive layer, but when they are optimized, the characteristics are brought out even more. Regarding metals, although aluminum also exhibits characteristics, the characteristics are more clearly exhibited in chromium, nickel, iron, and vapor-deposited metal films containing at least one of these as a main component. Furthermore, even among vacuum deposition in a broad sense, these metal films deposited by sputtering are more distinctive. In addition, in the transfer body obtained by transferring the hot stamping foil made as described above with the blended resin composition of the resins () and () of the present invention, the blended resin intervening layer 6 and/or 7 has good solvent resistance and chemical resistance. , water resistance, weather resistance, etc., the disadvantages of the adhesive layer 5 having poorer properties can be overcome here.

Examples will be given below to clarify and supplement the above effects.

Example 1 A biaxially stretched polyethylene terephthalate film with a thickness of 25 microns was treated with an easily wettable anchor coat, and then acetone 5 of cellulose acetate was applied.
% solution with a gravure coater roll,
It was dried at 120°C to form a solid release layer with a thickness of about 0.2 microns.

On top of this release layer, a xylene/isobutyl alcohol solution of an acrylic copolymer consisting of methacrylic acid, 2-hydroxyethyl methacrylate, acrylamide, butyl acrylate, methyl methacrylate, and n-butyl methacrylate is added to Mitsui Toatsu. Melamine paint “Yuban” 20SE (solid content 60
%) was mixed with 100 parts (solid content equivalent) of the acrylic copolymer and diluted with a mixed solvent containing the solvent, toluene, and ethyl acetate to make a 25% solids paint. It was coated with a coater and dried at 160°C for 1 minute to obtain a cured coating film which became a protective layer after hot stamping with a solid thickness of 8 microns.

Chromium was deposited directly onto the protective resin layer to a thickness of 300 Å by direct current sputtering.

A resin paint AC-1 prepared by mixing an acrylic copolymer (I ₁ ) and an epoxy resin ( ₁ ) prepared by the following method was coated on the vapor-deposited chromium layer.

That is, in a container equipped with a condenser, thermometer, and stirrer, 80 parts of toluene, 20 parts of isobutanol, 10 parts of diethylaminoethyl methacrylate, 58 parts of methyl methacrylate, 30 parts of butyl acrylate, and 2-hydroxyethyl methacrylate. 2 parts, 1 part of n-dodecylmercaptan, 1 part of azobisisobutyronitrile
After stirring at 80° C. for 2 hours, 0.2 parts of azobisisobutyronitrile was added three times every 2 hours, and the polymerization was completed in 12 hours to obtain an acrylic copolymer (I ₁ ).

Add 5 parts of sorbitol polyglycidyl ether (“Denacol” EX-611 manufactured by Nagase Sangyo Co., Ltd.) to 100 parts of the above ( ₁ ), mix well, and then add toluene, xylene, and isobutanol to reduce the total solids. A solution paint (AC-1) containing 5% by weight was prepared.

The AC-1 paint was coated on the above sputtered chromium film using a gravure roll coater, and immediately dried and crosslinked at 150°C for 1 minute to form a coating layer with a solid content of 0.3 microns.

A 20% solution of poly-n-butyl methacrylate dissolved in toluene-methyl ethyl ketone solvent was coated on the AC-1 coating layer and dried at 150°C for 1 minute to form a thermoplastic adhesive layer with a thickness of 2 microns. A hot stamping foil was obtained.

The hot stamping foil has a 3 mm width pitch, its surface is uniformly aligned, but it has convex portions, and
Stamping was performed for 2 seconds on an ABS resin molded substrate similarly having recesses (grooves) using an up-down stamping machine (manufactured by Ohira Kogyo Co., Ltd.) equipped with a silicone rubber hot plate heated to 180°C. As a result, the foil separation was good, the foil cut was also good,
There was almost no residual foil at the edges of the 3 mm pitch protrusions. Further, the metallic luster of the chromium metal film was not cloudy, there was no peeling or cleavage between the coated layers, and there was no discoloration. Further, after the hot stamp stamping, there was no problem even when the hot stamping foil was peeled off almost in the lateral direction and transported at a fairly high speed with impact.

The stamped product was immersed in warm water at 40℃ for 72 hours, but there was no change in appearance, and the adhesion, abrasion resistance, hardness,
The weather resistance was also good with no change.

Further, there was no change even after immersing it in gasoline for 1 hour. It has been confirmed that these hot stamping foils can be effectively used on various plastic molded substrates, mainly for the exterior of automobiles, home appliances, miscellaneous goods, etc.

Comparative Example 1 A stamping foil was prepared in exactly the same manner as in Example 1, except that no AC-1 resin paint was applied on the sputtered chrome film.

When the hot stamping foil was hot stamped in the same manner as in Example 1, the foil was not easy to cut. That is, there was a jagged residue of the foil at the end of the convex portion of the transfer substrate of the coating layer including the adhesive layer. Also, the separation from foil was even worse. This is presumed to be because the entire laminated coat foil layer does not have an integrated property, and therefore, during mold release, it is difficult for mold release stress to instantaneously concentrate on the mold release layer interface.

Furthermore, due to the heat and pressure during stamping, microcracks were likely to form mainly in the chromium metal film layer, and the metallic luster became dull and cloudy. To try to alleviate this, lowering the hot stamping temperature and pressure will improve the situation a little, but in that case,
The adhesive layer did not adhere very strongly to the ABS resin transfer substrate, making it unusable. In addition, especially when the hot stamping foil is transported at high speed almost laterally immediately after stamping, delamination occurs mainly at the interface between the chromium metal film layer and the adhesive layer, or sometimes also at the interface between the protective layer and the chromium metal film layer. Cleavage etc. occurred.

The stamp product was subjected to various evaluations in the same manner as in Example 1, but the hot water resistance test and gasoline resistance were also poor.
Abrasion resistance also decreased. Also, the weather resistance measured by a weatherometer was not good.

Example 2 In Example 1, AC-1 resin paint was coated next to the protective layer to a solid thickness of 0.1 micron and cured, then chromium was sputtered in the same manner, and AC-1 was applied again in the same manner. 1 After coating and curing the resin paint, we similarly coated the adhesive layer to create a hot stamping foil and evaluated it.
The behavior was almost the same as in Example 1 and was good.

Example 3 A carrier film and a base material coated with a release agent were used in the same manner as in Example 1, and a protective layer containing polybenzyl methacrylate resin as the main component was solution-coated using a reverse roll coater.
It was dried for 1 minute at 0.degree. C. to form a solid thickness of 4 microns. This was coated with resin paint AC-2, which was a mixture of acrylic copolymer ( ₂ ) produced using the same equipment and method as in Example 1, and epoxy resin ( ₂ ).

Namely, 80 parts of toluene, 20 parts of isobutanol, 1 part of acrylic acid, 4 parts of dimethylaminoethyl methacrylate, 44 parts of methyl methacrylate, 20 parts of styrene.
1 part, 30 parts of ethyl acrylate, and 1 part of azobisisobutyronitrile, stirred at 80°C for 2 hours, and then added 5 times of azobisisobutyronitrile every 2 hours.
After adding 0.3 part, polymerization was completed in 16 hours to obtain an acrylic copolymer ( ₂ ).

Diglycerol polyglycidyl ether (“Denacol” EX-421 manufactured by Nagase Sangyo Co., Ltd.) (equivalent to epoxy resin ( ₂ )) was blended with 100 parts of this acrylic copolymer ( ₂ ), and further, toluene and isobutanol were added. A resin paint AC-2 with a solids content of 5% by weight was prepared by adding thinner.

The AC-2 was coated on the protective layer by gravure roll coating, dried and crosslinked at 150°C for 1 minute to form a solid coating layer with a thickness of 0.2 microns, and on top of that, aluminum was coated by induction heating. The film was deposited to a thickness of 500 Å using a conventional semi-continuous vacuum deposition machine. Then, on the aluminum vapor deposited film,
AC-2 was again coated, dried and cross-linked in the same manner to form a coating layer with a solid thickness of 0.1 to 0.2 microns, and then poly(n-butyl methacrylate, iso-
A 20% solution of thermoplastic acrylic resin (butyl methacrylate) as the main component was coated using reverse roll coating, and dried at 150°C for 1 minute to form an adhesive layer with a thickness of 2 microns to obtain a hot stamping foil. Ta.

The hot stamping foil was hot stamped onto an ABS substrate in the same manner as in Example 1 and showed similarly good process and quality characteristics.

Comparative Example 2 In Example 2, a hot stamping foil was formed in the same manner as in Example 2, except that the AC-2 resin paint was not coated on the protective layer and the vapor-deposited aluminum metal film layer.

This was hot-stamped in the same manner as in Example 1, but first, peeling occurred between the aluminum layer and the protective layer, and the aluminum film, including the protective layer, became white and microcracks appeared. In addition, the foil did not cut easily, and the foil remained in a jagged pattern on both the protective layer and the adhesive layer, similar to Comparative Example 1. Furthermore, when the hot stamping foil was transferred laterally after hot stamping, delamination and cleavage occurred at the interface between each coat layer.

The stamped product was subjected to various evaluations in the same manner as in Example 1.
Weather resistance was also considerably inferior, and in some cases significantly inferior.

[Brief explanation of the drawing]

FIG. 1 shows a structure b of a hot stamping foil and a hot stamping mechanism comprising the method of the invention. a and 10 are plate-like objects that apply heat and pressure;
c and 9 indicate the molded products to which the transfer was applied. 1 is a substrate such as a carrier film, 2 is a release agent layer, 3 is a protective layer, 4 is a vapor deposited metal film layer, 5 is an adhesive layer, 6 is a coat layer before metal vapor deposition, and 7 is a coat after metal vapor deposition in,
Both 6 and 7 are layers that are in direct contact with the vacuum-deposited film layer.

Claims (1)

[Claims] 1. In a hot stamping foil on which metal vapor deposition is applied, at least one of the layers directly in contact with the vapor deposited metal film contains (a) a basic nitrogen-containing acrylic monomer;
0.2-30% by weight (b) Acrylic acid or methacrylic acid and aliphatic 1
35 to 99.8% by weight of an ester with a hydrovalent alcohol; and (c) an acrylic monomer having a group selected from a carboxyl group, a hydroxyl group, a glycidyl group, a nitrile group and an amide group; a carboxyl group,
A methacrylic monomer having a group selected from a hydroxy group, a glycidyl group, a nitrile group, and an amide group; 0 to 60% by weight of a monomer selected from styrene; α-methylstyrene; vinyltoluene and vinyl acetate. Acrylic copolymer as a copolymer component ()
and a compound or polymer () having at least two epoxy groups per molecule.