JP2004243580A - Manufacturing method of embossed resin film coated metal sheet - Google Patents

Abstract

An object of the present invention is to provide a method for producing a metal plate coated with an embossed resin film, which is capable of exhibiting a sufficient design property while maintaining an uneven shape.
When laminating a polyester resin film having an embossed groove to a metal plate, the embossing is performed when the film is separated from a laminating roll and / or simultaneously with or after laminating the polyester resin film to the metal plate. The cooling time from when the embossing roll separates from the film during processing until the film surface temperature falls below the freezing temperature of the constituent resin components is within the resin's strain relaxation time measured by the dynamic viscoelasticity measurement method. A method for producing a metal plate coated with an embossed resin film, characterized by using a quenching means for controlling the temperature of the metal sheet to be embossed.
[Selection diagram] None

Description

【００４４】
（実施例９，１０、比較例４）
ＰＢＴ（固有粘度１．２、Ｔｍ：２２３℃）をアイボリー色に調色し、加熱溶融し（Ｔダイス温度２５０℃）、押し出し成形にて１２５μｍ厚さの平滑表面フィルムを得た。得られた当該フィルムを、オーブンで再加熱し、革シボエンボス加工を施したキャスティングロールとバックアップロール間に、樹脂が当接するように押し出し、エンボスロール径、ニップ圧およびラインスピードを設定し、エンボス加工で押している時間（Δｔ）０．２０秒となるように調節し、１２５μｍ厚さの革シボエンボスフィルム（平均エンボス溝深さは２５μｍ）を得た。
【００４５】
板厚０．４５ｍｍの溶融亜鉛メッキ鋼板表面にクロメート処理し、２液型ポリエステル樹脂接着剤を乾燥膜厚で４μｍになるように塗布した。塗布後、オーブンで最高到達板温が２３０℃となるように加熱乾燥し、直ちに前記フィルムのエンボス加工面の反対面が接着剤層に接するようにニップで圧着積層した。積層直後に鋼板表裏面を、当該樹脂のＴｃ（冷結晶化温度：１９３℃）まで冷却される時間を、表裏面ミスト冷却法および／又は水冷にて、０．２〜１．２秒の範囲の条件で冷却し、鋼板温度が常温にまで低下した時点で、エンボス溝の形状保持率を評価した。なお、当該樹脂の２３０℃でのｔａｎδの値は３．０×１０^１ であった。結果を表２に示した。
【００４６】
【表２】

【００４７】
（実施例１１〜１４、比較例５〜６）
ＰＥＴのグリコール成分であるエチレングルコールを３０モル％シクロヘキサンジメタノールに置き換えた共重合ＰＥＴ樹脂（Ｔｇ：８０℃）をアイボリー色に調色し、加熱溶融し（Ｔダイス温度２５０℃）、革シボエンボス加工を施したキャスティングロールとバックアップロール間に、樹脂が当接するように押し出し、エンボスロール径、ニップ圧およびラインスピードを設定し、エンボス加工で押している時間（Δｔ）０．１２〜０．２０秒となるように調節し、１００μｍ厚さの革シボエンボスフィルム（平均エンボス溝深さは２０μｍ）を得た。
【００４８】
板厚０．４５ｍｍの溶融亜鉛メッキ鋼板表面にクロメート処理し、２液型ポリエステル樹脂接着剤を乾燥膜厚で４μｍになるように塗布した。塗布後、オーブンで最高到達板温が２３０℃となるように加熱乾燥し、直ちに前記フィルムのエンボス加工面の反対面が接着剤層に接するようにニップ圧着積層した。積層直後に鋼板表裏面を、当該樹脂のＴｇ（ガラス転移温度：８０℃）まで冷却される時間を、表裏面ミスト冷却法および／又は水冷にて、０．４〜１．５秒の範囲の条件で冷却し、鋼板温度が常温にまで低下した時点で、エンボス溝の形状保持率を評価した。なお、当該樹脂の２３０℃でのｔａｎδの値は３．４×１０^１ であった。結果を表３に示した。
【００４９】
【表３】

【００５０】
（実施例１５〜１８、比較例７〜１０）
実施例１と同様に、ＰＥＴのグリコール成分であるエチレングリコールを３０モル％シクロヘキサンジメタノールに置き換えた共重合ＰＥＴ樹脂をアイボリー色に調色し、加熱溶融し（Ｔダイス温度２５０℃）、押し出し成形にて８０μｍ厚さの平滑表面フィルムを得た。
【００５１】
板厚０．４５ｍｍの溶融亜鉛メッキ鋼板表面にクロメート処理し、２液型ポリエステル樹脂接着剤を乾燥膜厚で４μｍになるように塗布した。塗布後、オーブンで最高到達板温が２３０℃となるように加熱乾燥した。前記フィルムを、同鋼板の片面に、２３０℃に加熱した実施例１１と同様の革シボエンボスロール（フィルム側）−ゴムロール（鋼板側）を用いて圧着すると同時にエンボス加工（加工時間０．１６秒、０．２秒に調節、最大エンボス溝深さは２０μｍ）を施し、エンボスロールにてエンボス溝が形成された直後から当該樹脂のＴｇ（ガラス転移温度：８０℃）まで冷却される時間を、裏面ミスト冷却法および／又は水冷にて、０．５〜１．５秒の範囲の条件で冷却し、鋼板温度が常温にまで低下した時点で、エンボス溝の形状保持率を評価した。この場合、同評価は実施例１１で得られたエンボスフィルムを基準とした。なお、当該樹脂の２３０℃でのｔａｎδの値は３．４×１０^１ であった。結果を表４に示した。
【００５２】
【表４】

【００５３】
（実施例１９〜２０及び比較例１１〜１２）
実施例１と同様に、ＰＥＴのグリコール成分であるエチレングルコールを３０モル％シクロヘキサンジメタノールに置き換えた共重合ＰＥＴ樹脂をアイボリー色に調色し、加熱溶融し（Ｔダイス温度２５０℃）、押し出し成形にて８０μｍ厚さの平滑表面フィルムを得た。
【００５４】
板厚０．４５ｍｍの溶融亜鉛メッキ鋼板表面にクロメート処理し、２液型ポリエステル樹脂接着剤を乾燥膜厚で４μｍになるように塗布した。塗布後、オーブンで最高到達板温が２３０℃となるように加熱乾燥した。前記フィルムを、同鋼板の片面に圧着した。当該鋼板を、オーブンで２１０℃に再加熱し、革シボエンボスロールにてエンボス加工を施し（加工時間０．１２秒、０．２０秒に調節、平均エンボス溝深さは２０μｍ）、エンボスロールにてエンボス溝が形成された直後から当該樹脂のＴｇ（ガラス転移温度：８０℃）まで冷却される時間を、裏面ミスト冷却法および／又は水冷にて、０．５〜１．５秒の範囲の条件で冷却し、鋼板温度が常温にまで低下した時点で、エンボス溝の形状保持率を評価した。この場合も、同評価は実施例１１で得られたエンボスフィルムを基準とした。なお、当該樹脂の２１０℃でのｔａｎδの値は３．２×１０^１ であった。結果を表５に示した。
【００５５】
【表５】

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a method for producing a resin film for decorative laminate and a decorative plate on which the resin film is laminated. More specifically, the present invention relates to a method for producing an embossed resin film-coated metal sheet suitable for producing a resin-coated metal sheet having a design property by embossing for use as a building material.
[0002]
[Prior art]
BACKGROUND ART Resin films having irregularities on the surface and a mat or a design on the surface are widely used as embossed films as films for covering inside / outside of building materials, furniture, and housing of home appliances. Conventionally, polyvinyl chloride (PVC) has been used in this field, but non-PVC has been promoted from the viewpoint of global environment and waste contamination, and alternative materials of the resin have been rapidly spread.
[0003]
Polyolefin such as polypropylene (PP) may be used as a non-PVC resin material. The PP film has a feeling similar to that of a PVC film and can be embossed, and is disclosed in Japanese Patent Application Laid-Open No. 7-290642. However, since the PP film has insufficient surface hardness as compared with PVC, it has problems such as scratching property and quasi-noncombustibility.
[0004]
Polyester resin is also an effective material as a non-PVC resin.
[0005]
Generally, a polyester film is often used after being biaxially stretched. However, the biaxially stretched film has no flexibility for embossing the surface, or shrinks when heated at a high temperature to impart flexibility, thereby making embossing difficult. In Japanese Patent Application Laid-Open No. 9-24588, embossing is enabled even in a stretched film by laminating a polyester having a low melting point (low Tm) on the upper layer and a high Tm on the lower layer. By appropriate heat treatment, the upper polyester layer is softened, and the lower polyester layer retains its shape and prevents shrinkage.
[0006]
Further, it is disclosed that embossing can be performed regardless of stretching or non-stretching by defining the polyester component. Specifically, JP-A-2000-301662 and JP-A-2001-341261 disclose a film in which 1,4-cyclohexanedimethanol (CHDM) is copolymerized with polyethylene terephthalate (PET) as a glycol component of a polyester; JP-A-2001-164001 and JP-A-2001-200073 disclose a technique in which embossing can be achieved by using a film obtained by alloying PET and polypropylene terephthalate (PPT) or the like.
[0007]
Further, JP-A-2001-310955 discloses a technique of adding a plasticizer such as polyether to soften a surface layer of a polyester film and embossing the same, and JP-A-2001-287326, JP-A-2002-172737, JP-A-2002-225186 discloses a technique in which a relatively flexible polyester component such as polybutylene terephthalate (PBT) is laminated on a surface layer to emboss.
[0008]
[Patent Document 1]
JP 2002-225186 A
[Problems to be solved by the invention]
However, these techniques disclose how to transfer embossed grooves of a polyester resin film, but do not disclose a technique for maintaining an embossed shape after laminating a film on a metal material. When laminating an embossed film on a metal, in order to ensure sufficient adhesion between the metal plate and the film, the metal material is generally coated with a melting point temperature Tm ± 50 ° C. and / or a glass transition temperature Tg + (100 ° C. to 200 ° C.). (° C.) and a method of coating on the heating plate. At this time, in many cases, the uneven shape of the embossed groove is changed (returned) by heating, and the embossed shape cannot be maintained, so that the imparted embossed design is easily damaged. Therefore, even if the film is embossed by these disclosed technologies, if the processing conditions are not optimized, the distortion is relaxed when laminating to a heated metal, and the uneven shape of the surface is changed, and sufficient design properties are obtained. In many cases, it could not be demonstrated.
[0010]
An object of the present invention is to provide a method for manufacturing an embossed resin film-coated metal sheet that can maintain a concave-convex shape and express sufficient designability in view of the above-described conventional technology.
[0011]
[Means for Solving the Problems]
The present inventors have found that the change in the embossed groove transferred to the film surface is caused by the softening of the crystal or amorphous portion that has frozen the embossed groove due to heating and the distortion is relaxed. It was found that the strain was frozen before the embossed groove was relaxed, and the present invention was reached.
[0012]
That is, in the present invention, when laminating a polyester resin-based film having an embossed groove to a metal plate (meaning a case where a film processed by an in-line embossing method or an after-embossing method described later is laminated), the film is rolled down by laminating. And / or embossing at the same time as or after laminating the polyester resin-based film on the metal plate (meaning the later-described lamination simultaneous embossing method and post-laminating embossing method). Controls the cooling time from when the roll separates from the film until the film surface temperature drops below the freezing temperature of the constituent resin components, within the resin's strain relaxation time measured by the dynamic viscoelasticity measurement method Resin film coating characterized by using rapid cooling means Genus plate is a manufacturing method.
[0013]
Further, there is provided a method for producing an embossed resin film-coated metal sheet, characterized by using a mist cooling method as an effective cooling method after heat processing called embossing.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
In order to secure the adhesion between the resin film to be coated and the metal plate, the embossed polyester resin film-coated metal plate of the present invention, in the case of crystalline polyester, has a temperature around the melting point (Tm) of the resin (for example, Tm ± It should be laminated at a temperature range of not more than 50 ° C.), typically at a temperature of Tm or higher, and in the case of amorphous polyester, at a temperature of the glass transition temperature (Tg) of the resin + 100 ° C. to 200 ° C. It is an object of the present invention to solve the problem that the embossed grooves are easily deformed by such a high-temperature heat treatment, thereby deteriorating the quality of the decorative board having the embossed grooves. In the present invention, the deformation rate of the embossed groove is prevented by controlling the cooling rate after the heating.
[0015]
In the present invention, a known processing method can be arbitrarily applied to the embossing method. The main processing methods are described below. Among them, the in-line and laminating simultaneous embossing methods are preferable because they can be processed at a high temperature because they can be processed in the flow region of the resin and can easily control the residual strain energy.
[0016]
The in-line embossing method involves embossing when a plasticized resin (a temperature of Tm or more and / or a temperature of (Tg + 100 ° C. to 200 ° C.)) immediately below a T-die of a film forming apparatus is cast (film forming and spreading). This is a method in which an embossed pattern is transferred onto the film surface simultaneously with the film formation using a roll that has been applied (generally, a metal; room temperature to about 50 ° C.) and a backup roll (generally, a heat-resistant rubber; Therefore, in particular, in the case of crystalline polyester, embossing can be performed at a temperature close to Tm of the resin (flow region of the resin).
[0017]
In the after-embossing method, a film formed once is reheated and softened in an oven or the like (the temperature immediately before the film softens and starts to elongate; the upper limit is about 180 ° C. for a PBT film), and the embossed roll (generally, In this method, an embossed pattern is transferred onto the film surface using a metal (room temperature: about 50 ° C.) and a backup roll (generally, heat-resistant rubber; room temperature to about 50 ° C.). Therefore, in the case of crystalline polyester, in particular, the temperature cannot be set near the Tm of the resin, and embossing is performed from the elastic range of the resin to just before the flow range, which limits the processing temperature range.
[0018]
In laminating and embossing simultaneously, when laminating a film once formed on a steel sheet, a roll (generally a metal; for example, a temperature near Tm can be set) and a backup roll (generally a heat-resistant rubber; This is a method in which an embossed pattern is transferred onto the film surface simultaneously with lamination on a steel plate (for example, heated to a temperature near Tm). For example, the PBT film can be carried out at a steel sheet temperature of 210 ° C. and an emboss roll 210 ° C.
[0019]
In the post-lamination embossing method, after laminating a film on a steel sheet, the laminated steel sheet is reheated in an oven or the like (for example, heated to a temperature near Tm) to soften the resin portion and emboss roll (generally metal; room temperature to about 50 ° C.). ) And a backup roll (generally heat-resistant rubber; room temperature to about 50 ° C.) to transfer an embossed pattern onto the film surface. For example, after laminating a PBT film at a steel sheet temperature of 210 ° C., the sheet is reheated to 200 ° C. in an oven, and can be carried out using an emboss roll (room temperature to about 50 ° C.).
[0020]
In the present invention, the strain relaxation time τ of the resin constituting the film is defined as follows.
[0021]
The measuring device can be measured using a known dynamic viscoelasticity measuring device. Specifically, there are a vibron type and a rheometer type measuring device for measuring a mechanical response by giving a sinusoidal vibration to a solid resin or a liquid vibration. If the resin temperature during processing is very high and there is no self-supporting property as a film, liquefy the film and use a rheometer-type measuring device. It is preferable to measure with an apparatus. In the case of polyester, the embossing temperature is often set to around the melting point (Tm) and / or the glass transition temperature (Tg) + 100 ° C. to 200 ° C. When measured directly with a vibron-type measuring device as it is, an accurate value cannot be obtained. Therefore, it is more preferable to perform measurement using a rheometer-type measuring device.
[0022]
The measurement conditions of the strain relaxation time are as follows: frequency: 1 rad / sec, and temperature:
[0023]
That is, in the case of the in-line method or the after-embossing method (laminate the film in which the emboss grooves are transferred to a steel plate), the measurement is performed at the heating plate temperature immediately before lamination. For example, the temperature is generally 230 ° C. for vinyl chloride and 200 to 240 ° C. for polyethylene terephthalate. If an adhesive is used, it depends on the type. However, if the temperature exceeds 240 ° C., the discoloration of the added color pigment occurs in the polyester-based resin film, which may have a bad influence on the design, so that it is generally not preferable.
[0024]
In the case of the lamination simultaneous embossing method and the lamination embossing method (transfer of the embossed groove at the time of lamination or later), the measurement is performed at the plate temperature at the time of contact with the embossing roll. For example, in PBT, 200-240 degreeC is common.
[0025]
The storage elastic modulus E ′ and the loss elastic modulus E ″ of the resin constituting the film are measured under the above conditions, tan δ (= E ″ / E ′) is calculated from the measured values, and the strain relaxation time τ is determined according to the following equation.
[0026]
τ = (1 / ω) × tan δ
Here, ω = 2π / Δt, and Δt is the time (second) during which embossing is performed, and is actually measured. In all the processing methods, the “time Δt pressed during embossing” is defined as the time sandwiched between the embossing roll and the backup roll, and is actually measured. Δt can be changed by the embossing roll diameter, the nip pressure and the line speed.
[0027]
In the present invention, the freezing temperature of the resin constituting the film is a cold crystallization temperature (Tc) in the case of a crystalline resin. Tc is determined by heating and melting a resin at a temperature equal to or higher than its melting point (Tm) and cooling the resin from a high temperature to a low temperature at a constant rate by a differential scanning calorimeter (DSC) (for example, a sample amount of 10 mg, a cooling rate of 10 ° C./min). ), Can be measured as the temperature at which the resin recrystallizes. In the DSC measurement, the same temperature is observed as a broad endothermic peak, and here, it is defined as the temperature at the peak top.
[0028]
In the case of an amorphous resin, it is the glass transition temperature (Tg). A commonly used temperature at which the motility of the polymer backbone freezes, the temperature at which it changes from a molten state to a solid state.
[0029]
In the present invention, the cooling time of the film to the above-mentioned freezing temperature after lamination for the embossed film or after embossing for the lamination simultaneously or after embossing is controlled to the relaxation time τ (second) or less. The upper limit of the cooling time is preferably 1 second.Specifically, in the in-line embossing method and the after-embossing method, the cooling time from immediately after the embossed film is separated from the laminating roll, until the freezing temperature is reached, In the lamination simultaneous embossing method and the post-lamination embossing method, it is a cooling time from immediately after the emboss groove is transferred to the film surface by the embossing roll until the freezing temperature is reached. The relaxation time τ (seconds) is preferably ４ or less, more preferably １ or less.
[0030]
By controlling the cooling time to be equal to or less than the relaxation time τ (second), it is possible to maintain the embossed shape after heating. By satisfying the cooling condition, the embossed shape can be maintained without depending on the embossing condition and the resin composition of the film.
[0031]
In order to achieve the above cooling conditions, special quenching means is used. Specifically, a mist cooling method is effective. The mist cooling method is a method of spraying cooling water in a mist state to rapidly cool using latent heat of evaporation, and is effective as a specific cooling method satisfying the rapid cooling condition of the present invention. By using the mist cooling method alone or in combination with the water cooling method, the cooling rate of most resin films can be controlled to preferably less than 0.3 seconds, and more preferably 0.2 seconds or less. However, other methods may be used as long as the front and back surfaces can be rapidly cooled. Generally, a method of cooling the front and back surfaces with cooling water whose temperature is controlled can also be adopted.
[0032]
The polyester resin film used in the present invention is a film containing a polyester resin as a main component. As the polyester resin, a known polyester resin film can be used. Preferred films are polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and modified polyethylene terephthalate (for example, copolymerized modified PET in which terephthalic acid as an acid component of PET is partially replaced with isophthalic acid; PET-I), modified Polybutylene terephthalate (for example, copolymerized modified PBT in which terephthalic acid as an acid component of PBT is partially replaced with isophthalic acid; PBT-I), and ethylene glycol as a glycol component of polyethylene terephthalate is partially replaced with cyclohexanedimethanol Copolymerized modified polyethylene terephthalate (for example, PET-G), polyethylene naphthalate (PEN), polypropylene terephthalate (PPT), polyarylate (wholly aromatic polyester; PAr). More preferred films are PET, PBT, PET-I, PBT-I, PET-G, and PEN, and PBT is particularly preferred in terms of dimensional stability and economy.
[0033]
As the resin, a resin component other than the polyester may be added to the polyester. For example, a mixed resin of a polyester and a vinyl polymer containing a polar unit, or a mixed resin of a polyester and a vinyl polymer containing a polar unit and a rubber-like elastic material may be used. In the case of the two-type mixed resin, a resin having a structure in which the polymer mixed resin is dispersed in a matrix with a particle diameter of 1.5 μm or less may be used, or in the case of the three-type mixed resin, a vinyl polymer has a capsule structure enclosing a rubber-like elastic material. Alternatively, a resin having a structure in which the particles are dispersed with a particle size of 1.5 μm or less may be used. These resin compositions have excellent mechanical properties for producing an embossed resin film coated with a metal plate.
[0034]
The resin may optionally contain additives such as a coloring pigment, an extender pigment, a rust-preventive pigment, an ultraviolet absorber, and an antioxidant.
[0035]
The polyester resin of the polyester resin film used in the present invention may be stretched or unstretched, but is preferably unstretched from the viewpoint of emboss transferability.
[0036]
The embossed shape is arbitrary, such as embossed leather or satin. However, the average emboss groove depth / film thickness is preferably 0.1 to 0.4. If this ratio exceeds 0.4, it becomes impossible to keep the strain energy remaining in the embossed groove low, and it becomes difficult to maintain the embossed shape by heat. In addition, irregularities of the embossed pattern may affect the back surface of the film, which may adversely affect adhesion during lamination. The film thickness is generally from 50 to 300 μm, preferably from 70 to 150 μm, but is not limited. When the lamination simultaneous embossing method and the post-laminating embossing method are used, a thin film can be formed, which is economically preferable.
[0037]
【Example】
The following measurement methods were employed in Examples and Comparative Examples.
[0038]
(Dynamic viscoelasticity measurement method)
-Measuring equipment: Rheometer (Rheometrics RDA-700)
・ Specimen: Cut out from a press sheet ・ Plate diameter: r = 12.5mm
・ Gap: 0.6mm
・ Frequency: 1 rad / sec
・ Measurement: Temperature was changed from a high temperature (250 ° C.) to a low temperature and measured at each temperature to check the temperature dependency (emboss retention).
The evaluation of the embossability was performed by measuring the average emboss groove average depth (d1) of the embossed film, and measuring the average emboss groove depth (d2) of the film after lamination of the steel sheet with respect to the measured value. The average depth ratio was determined and evaluated in the following three grades.
[0039]
Emboss retention rate = (d2 / d1) × 100 (%)
：: 80 to 100% retention, Δ: 50 to 80%, ×: 50% or less (measurement of temperature change)
The change in the surface temperature of the steel plate or film is measured by attaching a thermocouple to the steel plate or film and measuring the temperature change.
[0040]
(Measurement of pressing time Δt during embossing)
The pressing time is calculated from the embossing roll diameter, the relationship between the nip pressure and the film thickness, and the line speed.
[0041]
(Measurement of cold crystallization temperature)
Apparatus: Differential scanning calorimeter DSC (manufactured by Rigaku Corporation, DSC8230) Apparatus Sample amount: about 10 mg (comparative standard sample: Al ₂ O ₃ )
Temperature conditions: After heating from 30 ° C to 270 ° C (heating rate 10 ° C / min), cooling from 270 ° C to 50 ° C (cooling rate 10 ° C / min)
Measurement atmosphere: in the air (Examples 1 to 8, Comparative Examples 1 to 3)
PBT (intrinsic viscosity 1.2, Tm: 223 ° C.) is toned in ivory, heated and melted (T die temperature 250 ° C.), and the resin comes into contact between the casting roll and the backup roll that have been subjected to leather embossing. The embossing roll diameter, the nip pressure and the line speed are set as described above, and the embossing time (Δt) is adjusted to be 0.16 to 0.08 seconds, and the leather embossed film (120 μm thick) is used. The average emboss groove depth was 25 μm).
[0042]
A surface of a hot-dip galvanized steel sheet having a thickness of 0.45 mm was subjected to chromate treatment, and a two-component polyester resin adhesive was applied to a dry film thickness of 4 μm. After the application, the film was heated and dried in an oven so that the maximum attained plate temperature became 230 ° C., and immediately, the film was pressure-bonded and laminated with a nip so that the surface opposite to the embossed surface of the film was in contact with the adhesive layer. Immediately after lamination, the time for cooling the front and back surfaces of the steel sheet to Tc (cold crystallization temperature: 193 ° C.) of the resin is set in a range of 0.2 to 1.2 seconds by a front / back surface mist cooling method and / or water cooling. When the steel sheet temperature was lowered to room temperature, the shape retention of the embossed grooves was evaluated. The value of tan δ at 230 ° C. of the resin was 3.0 × 10 ¹ . The results are shown in Table 1.
[0043]
[Table 1]

[0044]
(Examples 9 and 10, Comparative Example 4)
PBT (intrinsic viscosity: 1.2, Tm: 223 ° C.) was toned in ivory, heated and melted (T die temperature: 250 ° C.), and extruded to obtain a 125 μm thick smooth surface film. The obtained film is reheated in an oven, and extruded between a casting roll and a backup roll that have been subjected to leather embossing so that the resin comes into contact with the film, and the embossing roll diameter, nip pressure, and line speed are set, and embossing is performed. The pressing time (Δt) was adjusted to be 0.20 seconds to obtain a leather embossed embossed film having a thickness of 125 μm (average emboss groove depth was 25 μm).
[0045]
A surface of a hot-dip galvanized steel sheet having a thickness of 0.45 mm was subjected to chromate treatment, and a two-component polyester resin adhesive was applied to a dry film thickness of 4 μm. After the application, the film was heated and dried in an oven so that the maximum attained plate temperature became 230 ° C., and immediately, the film was pressure-bonded and laminated with a nip so that the surface opposite to the embossed surface of the film was in contact with the adhesive layer. Immediately after lamination, the time for cooling the front and back surfaces of the steel sheet to Tc (cold crystallization temperature: 193 ° C.) of the resin is set in a range of 0.2 to 1.2 seconds by a front / back surface mist cooling method and / or water cooling. When the steel sheet temperature was lowered to room temperature, the shape retention of the embossed grooves was evaluated. The value of tan δ at 230 ° C. of the resin was 3.0 × 10 ¹ . The results are shown in Table 2.
[0046]
[Table 2]

[0047]
(Examples 11 to 14, Comparative Examples 5 to 6)
A copolymerized PET resin (Tg: 80 ° C.) in which ethylene glycol, which is a glycol component of PET, was replaced with 30 mol% cyclohexanedimethanol was toned in ivory, heated and melted (T die temperature: 250 ° C.), and leather embossed leather The resin is extruded between the processed casting roll and the backup roll so as to be in contact with the resin, the embossing roll diameter, the nip pressure and the line speed are set, and the pressing time during the embossing (Δt) is 0.12 to 0.20 seconds. To obtain a leather embossed embossed film having a thickness of 100 μm (average emboss groove depth is 20 μm).
[0048]
A surface of a hot-dip galvanized steel sheet having a thickness of 0.45 mm was subjected to chromate treatment, and a two-component polyester resin adhesive was applied to a dry film thickness of 4 μm. After the application, the film was heated and dried in an oven so that the maximum attained plate temperature was 230 ° C., and was immediately nip-pressed and laminated so that the surface opposite to the embossed surface of the film was in contact with the adhesive layer. Immediately after lamination, the time required to cool the front and back surfaces of the steel sheet to the Tg (glass transition temperature: 80 ° C.) of the resin is set to a value within a range of 0.4 to 1.5 seconds by a front / back surface mist cooling method and / or water cooling. When the steel sheet was cooled under the conditions and the temperature of the steel sheet dropped to room temperature, the shape retention of the embossed grooves was evaluated. The value of tan δ at 230 ° C. of the resin was 3.4 × 10 ¹ . The results are shown in Table 3.
[0049]
[Table 3]

[0050]
(Examples 15 to 18, Comparative Examples 7 to 10)
In the same manner as in Example 1, a copolymerized PET resin in which ethylene glycol, which is a glycol component of PET, was replaced with 30 mol% cyclohexanedimethanol was toned to an ivory color, heated and melted (T die temperature: 250 ° C.), and extruded. To obtain a smooth surface film having a thickness of 80 μm.
[0051]
A surface of a hot-dip galvanized steel sheet having a thickness of 0.45 mm was subjected to chromate treatment, and a two-component polyester resin adhesive was applied to a dry film thickness of 4 μm. After the application, it was heated and dried in an oven so that the maximum temperature of the plate reached 230 ° C. The film was pressure-bonded to one surface of the same steel plate using the same leather embossing roll (film side) -rubber roll (steel plate side) as in Example 11 heated to 230 ° C., and simultaneously embossing (processing time 0.16 seconds) , 0.2 seconds, the maximum emboss groove depth is 20 μm), and the time for cooling to Tg (glass transition temperature: 80 ° C.) of the resin immediately after the emboss groove is formed by the emboss roll, Cooling was performed under the conditions of 0.5 to 1.5 seconds by the backside mist cooling method and / or water cooling, and when the steel sheet temperature was lowered to room temperature, the shape retention of the embossed grooves was evaluated. In this case, the evaluation was based on the embossed film obtained in Example 11. The value of tan δ at 230 ° C. of the resin was 3.4 × 10 ¹ . The results are shown in Table 4.
[0052]
[Table 4]

[0053]
(Examples 19 to 20 and Comparative Examples 11 to 12)
As in Example 1, a copolymerized PET resin in which ethylene glycol, which is a glycol component of PET, was replaced with 30 mol% cyclohexane dimethanol was toned to an ivory color, heated and melted (T die temperature: 250 ° C.), and extruded. A smooth surface film having a thickness of 80 μm was obtained by molding.
[0054]
A surface of a hot-dip galvanized steel sheet having a thickness of 0.45 mm was subjected to chromate treatment, and a two-component polyester resin adhesive was applied to a dry film thickness of 4 μm. After the application, it was heated and dried in an oven so that the maximum temperature of the plate reached 230 ° C. The film was pressed on one side of the steel plate. The steel sheet was reheated to 210 ° C. in an oven, embossed with a leather embossing roll (working time adjusted to 0.12 seconds and 0.20 seconds, and the average emboss groove depth was 20 μm). Immediately after the embossed grooves are formed, the time for cooling to Tg (glass transition temperature: 80 ° C.) of the resin is set in the range of 0.5 to 1.5 seconds by the backside mist cooling method and / or water cooling. When the steel sheet was cooled under the conditions and the temperature of the steel sheet dropped to room temperature, the shape retention of the embossed grooves was evaluated. Also in this case, the evaluation was based on the embossed film obtained in Example 11. The tan δ value of the resin at 210 ° C. was 3.2 × 10 ¹ . Table 5 shows the results.
[0055]
[Table 5]

Claims (6)

When laminating a polyester resin film having an embossed groove to a metal plate when the film is separated from the laminating press roll, and / or when embossing simultaneously with or after laminating the polyester resin film to the metal plate Control the cooling time from when the embossing roll separates from the film until the film surface temperature drops below the freezing temperature of the constituent resin components so that it is within the resin's strain relaxation time measured by the dynamic viscoelasticity measurement method A method for producing a metal plate coated with an embossed resin film, characterized by using a quenching means. The method for producing an embossed resin film-coated metal sheet according to claim 1, wherein a mist cooling method is used as the quenching means. At least one selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, modified polyethylene terephthalate, modified polybutylene terephthalate, polyester containing cyclohexanedimethanol as a diol component, polyethylene naphthalate, polypropylene terephthalate, and polyarylate (wholly aromatic polyester) as the polyester resin. The method for producing an embossed resin film-coated metal sheet according to claim 1, comprising one kind. The embossed resin according to claim 1 or 2, wherein the polyester resin includes a mixed resin of a polyester and a vinyl polymer containing a polar unit, or a mixed resin of a vinyl polymer containing a polyester and a polar unit and a rubber-like elastic material. Manufacturing method of film-coated metal sheet. An embossed resin film-coated metal plate obtained by the method according to claim 1. The embossed resin film-coated metal plate according to claim 5, wherein the metal plate is a steel plate.