JP2005220359A - Resin film excellent in emboss processability, method for emboss processing and decorative metal sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin film which can be used in the construction materials such as a unit bath, and which has excellent emboss processability superior to that of conventional flexible polyvinyl chloride film, and to provide a decorative metal sheet having high grade feeling, rich in sensitivity and coated with the resin film. <P>SOLUTION: The method for emboss processing comprises coating a resin film of TMA relation value below 10 on a decorative metal sheet and performing emboss processing treatment by rolling treatment using a carving roll, wherein, on the basis of using Tss of softening starting temperature and Tse of softening ending temperature, which are measured by TMA (thermomechanical analysis), and Tmp measured by DSC (differential scanning calorimetry), the surface temperature Tr of a part where the roll contacts with the resin film is set in the range of Tss-10≤Tr≤Tse(°C) and Tr<Tmp(°C), wherein TMA relation value(°C)=Tse-Tss. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention is a resin film or sheet (hereinafter referred to as “resin”), which is used for building materials and industrial materials that require relatively water resistance, such as unit baths, water supply tanks, various industrial articles, cans, etc. It is related to the processing method of a resin film. The present invention also relates to a decorative metal plate coated with the resin film.

The decorative metal plate is widely used in building materials and industrial materials that require relatively water resistance, such as unit baths, water supply tanks, various industrial products, and cans. In this case, the main purpose of coating the resin film on the surface is to give the material metal plate an anticorrosive effect, but at the same time it has the purpose of giving the decorative metal plate a high-class feeling, and the embossed pattern has been conventionally used. It has been widely performed.
Conventionally, the material of the film to which the embossed pattern is added is used mainly for such purposes, mainly from the viewpoint of easy embossing and low cost. It has been.

However, soft vinyl chloride resin is softened by adding and mixing phthalic acids such as DBP (dibutyl phthalate) and DOP (dioctyl phthalate) as a plasticizer to facilitate molding. It is difficult to use in places where the height is high, and there are various problems in disposal of products containing them. Furthermore, the aesthetics of the product when the embossed resin film is bonded to a metal plate and laminated before use is often different depending on the metal plate used. In other words, the embossing treatment is used because there is a problem that the aesthetic sensibility such as high-quality feeling is easily influenced by the type of resin used in the product for the application and the embossing treatment conditions. It is preferable to carry out under optimum conditions in relation to the resin. Therefore, the combination of the type of resin and the optimum embossing conditions becomes a problem.

Hard vinyl chloride resin films from which a plasticizer is excluded have problems in that processability is inferior and embossing treatment is generally difficult, and the aesthetics of the resin obtained by embossing treatment are difficult to obtain. In addition, when using olefin resin polyethylene, polypropylene resin, etc. instead of vinyl chloride resin, the embossability of these resins is good, but when processed after being laminated on a metal plate, the processed part is There is a problem of whitening and impairing aesthetics.
In order to solve this problem, there is a proposal of adding and blending a rubber component. However, when the rubber component is added, a new problem arises in that the polyethylene resin is modified into a soft resin similar to vinyl chloride resin.

Polybutylene terephthalate resin is very promising as a coating material in this field because it has excellent properties such as water resistance and little deterioration in strength after standing in water. It was not put into practical use for this purpose because of its badness.
On the other hand, the optimum embossing conditions have not been studied so far and are often dealt with on the spot by accumulating empirical knowledge.

The present invention aims to solve the above-mentioned problems, and has a resin film excellent in embossing workability equal to or higher than that of a conventional soft vinyl chloride resin and a rich and high-quality sensibility coated with the resin film. An object is to provide a decorative metal plate.

The resin film according to claim 1 is characterized in that a TMA relation value given by the following formula is 10 or less.
TMA-related value (° C.) = Tse−Tss where Tss (° C.) is the softening start temperature measured by TMA Tse (° C.) is the softening end temperature measured by TMA Such a film is polybutylene terephthalate in resin It is necessary to contain.
Moreover, the embossing method of the resin film of Claim 2 uses the said resin film as a raw material, and when the resin film is coat | covered on a decorative metal plate, when embossing processing is performed by the reduction process by an engraving roll, The surface temperature Tr of the part where the roll comes into contact with the resin film is defined as Tss-10 ≦ Tr ≦ based on Tss, which is the softening start temperature measured by TMA, Tse, which is the softening end temperature, and Tmp measured by DSC. It is necessary to perform the embossing process by setting Tse (° C.) and Tr <Tmp (° C.), and the best embossing property can be obtained under these conditions.
Here, Tmp (° C.) is an endothermic peak temperature in the temperature rising process measured by DSC.
A decorative metal plate according to a third aspect is the film according to the first or second aspect, wherein the decorative metal plate is coated with a resin film treated under the embossing conditions as described above.

As a result, even when a resin film having such characteristics is laminated (laminated) and subjected to processing such as bending, there is no problem that the processed portion is whitened and the design is not impaired, and is equivalent to vinyl chloride resin. The above-described embossability could be improved, and the excellent properties of the polybutylene terephthalate resin and the like, such as water resistance and less deterioration in strength after standing in water, could be maintained as they were.

As a result of intensive studies on the relationship between the properties of the resin film and embossability, the inventors of the present invention are calculated from the softening start temperature Tss (° C.) and the softening end temperature Tse (° C.) by Thermo Mechanical Analysis (TMA). The TMA-related value (Tse-Tss) is a resin having a value of 10 or less. Examples of such a resin include a polybutylene terephthalate resin or a polyethylene terephthalate resin film containing a polybutylene terephthalate resin. .
When the resin film is used as a raw material and the resin film is coated on a decorative metal plate and then embossed by a sculpture roll, the surface temperature Tr of the part where the roll comes into contact with the resin film, Tss-10 ≦ Tr ≦ Tse (° C.) and Tr <Tmp (° C.) are set on the basis of Tss as the softening start temperature measured by TMA, Tse as the softening end temperature, and Tmp measured by DSC. By embossing treatment, the embossability of these resin films can be dramatically improved, and a product made of a decorative metal plate having the embossed film on the surface can be given a higher-class feeling than conventional products. I found.

The contents of the present invention will be described below.
In the present invention, a resin film is bonded to a metal plate in advance, and then the metal plate and the resin film are simultaneously passed through an engraving roll at a constant speed for embossing.
(Metal plate used)
In the present invention, the metal plate to which the resin film is bonded and laminated before the embossing treatment can be widely used as long as it is a steel plate, an aluminum plate, a copper plate, or the like. As the steel plate, a plain steel cold-rolled steel plate having a thickness of 0.10 to 1.20 mm is preferable. Among these, a plain steel cold-rolled steel sheet having a thickness of 0.10 to 0.50 mm is preferable. Among cold-rolled products, low-carbon or ultra-low carbon aluminum killed steel plates are preferably used. Steel plates and the like can also be used. The surface of these cold-rolled steel sheets is preferably surface-treated in terms of durability.
Surface treatment methods include plating, coating, etc. Examples of plating treatment include zinc plating, zinc-aluminum alloy plating, zinc-cobalt-molybdenum plating, tin plating, nickel plating, nickel / phosphorus plating, nickel There are cobalt plating, nickel / tin plating, and the coating process is performed by baking and coating various paints according to the properties.

(Resin film used)
The thickness of the resin film or the like is not particularly limited. For example, 0.02 to 0.30 mm, preferably 0.080 to 0.150 mm of polybutylene terephthalate (PBT) resin, various ratios of PBT and other resins. Blend resins such as polyethylene terephthalate (PET) resin, polycarbonate (PC) resin, ionomer resin and the like, blends of three or more of these resins, or copolymers of PBT with other resins or compounds, For example, a resin film of a copolymer with isophthalic acid or adipic acid, or a composite resin film obtained by laminating the above-described various resin films at different thickness ratios can be used.
These resin films or the like may contain colored resins or the like. The reason for using two or more kinds of blended resins is that, for example, a resin having excellent impact strength but poor adhesion to metal has good adhesion to metal in order to improve only the adhesion. This is a case in which various resins are blended, and the composite resin is used because a resin having excellent adhesive properties is used for the adhesive surface with the metal.

The resin used for these resin films is required to have a TMA-related value given by the following formula in the range of 10 or less.
TMA-related value (° C.) = Tse−Tss where Tss (° C.) is a softening start temperature measured by TMA, and Tse (° C.) is a softening end temperature measured by TMA.
When a resin film having such a TMA relation value is used as a raw material resin film and the resin film is coated on a decorative metal plate, the roll comes into contact with the resin film when embossing is performed by a reduction process using an engraving roll. The surface temperature Tr of the portion is defined as Tss-10 ≦ Tr ≦ Tse (° C.) and Tr <, with Ts being the softening start temperature measured by TMA, Tse being the softening end temperature, and Tmp being measured by DSC. It is necessary to perform the embossing process at Tmp (° C.).

These resin films are coated on a metal plate immediately before the embossing treatment. For the method of coating the resin film on the metal plate, an epoxy, polyester, or cyanoacrylate adhesive may be used, but it is simply crimped onto the metal plate that has been heated above the melting point of the resin You may adhere by the method. When the resin film and the metal plate are bonded by the thermocompression bonding method, it is preferable to treat the surface of the metal plate so as to obtain a strong adhesive force. As a surface treatment method for the metal plate, methods known in the art such as electrolytic chrome treatment and adhesion primer treatment can be employed.

The reason why the TMA relationship value of the resin is limited to 10 or less is that when embossing is performed using an uneven engraving roll (grained) with Ra = 11 μm, the average after embossing of a vinyl chloride resin film that has been conventionally used This is because the surface roughness Ra was 4.0 μm, and therefore, the average surface roughness standard for improving the embossability in comparison with the conventional product was Ra 4.0 μm. The reason why the embossability is improved by using such a resin film having a TMA-related value is that embossing treatment is performed within a certain temperature range of Tss as the softening start point and Tse as the softening end point. It is thought that because the resin can effectively absorb the compression energy and friction energy generated in this temperature range within this temperature range, the resin can maintain a high degree of strain even after cooling.

Moreover, when the resin film of such a TMA relation value is used as a raw material resin film, and the embossing process is performed using an engraving roll, the temperature of the portion where the surface of the roll is in contact with the raw material resin film is determined by TMA. Emboss by setting Tss-10 ≦ Tr ≦ Tse (° C.) and Tr <Tmp (° C.) with reference to Tss, which is the softening start temperature measured, Tse, the softening end temperature, and Tmp measured by DSC. The reason why the processing is performed is that when the embossing processing is performed in such a temperature range, the high-quality feeling of the product is extremely excellent.

Although there are still many unclear points regarding the relationship between the embossing temperature and the sensitivity of the laminated resin film with the decorative metal plate, there are still relatively many crystalline regions called the softening start temperature of the resin. Therefore, it is thought that giving a distortion leads to the generation of a high-class feeling. The reason why the roll surface temperature Tr is set to a very limited temperature range lower than Tmp (° C.) measured by DSC and lower than Tse measured by TMA is that the resin adheres to the roll during the embossing process. This is to prevent the workability from deteriorating.
In general, the relationship between the TMA relationship value and the average surface roughness Ra of the resin film tends to be inversely correlated. This average surface roughness Ra has a large relationship with the design value (designability) of the product, and a range of 4 μm or more is considered to be an appropriate value. In addition, the more preferable range of this average surface roughness Ra is 5-8.

In addition, a product using a decorative metal plate that is bonded and laminated with a resin film when such resin with a TMA value is used and the resin film is embossed together with a decorative metal plate that is bonded and laminated. For example, the luxury of a bath for bathing is based on the temperature of the part where the surface of the roll is in contact with the raw material resin film, Tss, which is the softening start temperature measured by TMA, and Tse, which is the softening end temperature. It is necessary to perform embossing by setting Tss-10 ≦ Tr ≦ Tse (° C.).

In addition, the second condition is to perform the embossing process by setting the roll surface temperature Tr to Tr ≦ Tmp (° C.) with reference to Tmp measured by DSC. When embossing is performed under such a combination of conditions, a product using a metal plate obtained by bonding and laminating a resin having a certain value related to TMA has a very good texture, that is, a high-grade product. There is a tendency to be obtained.

Measurements of specifications necessary for calculation of TMA-related values and DSC-related values were performed under the following conditions. First, specifications required for calculating TMA-related values were measured under the following conditions. Using TMA and TAS-300 manufactured by Rigaku Denki Co., Ltd. Needle when a load of 100 g is applied to a needle with 2 mmφ and tip R = 0.2 or less (tip angle 60 °) and the temperature is raised at 10 ° C./min. The penetration depth into the film was measured according to JIS-K-7196. FIG. 1 shows an example of a measurement curve of TMA related values. Here, the penetration degree of the needle is a value obtained by dividing the penetration depth by the film thickness.

As shown in FIG. 1, the softening end temperature Tse is a temperature obtained by a tangent intersection between a curve in which the degree of penetration changes abruptly and the base line after the softening ends. Similarly, the softening start temperature Tss is a temperature obtained from the tangent intersection of the tangent of the curve used in Tse and the base line in the vicinity thereof.
The Tmp measurement by DSC was performed under the following conditions. A differential calorimeter DSC-7 manufactured by Perkin Elmer was used, and a precisely weighed sample of about 5 mg was heated at 20 ° C./min in a nitrogen gas atmosphere, and the endothermic peak was defined as the melting point Tmp of DSC.

(Embossing processing method)
Embossing treatment method for resin film, etc., for example, a method of passing a multilayer film directly between chilled rolls, a method of heating a brown film between chilled rolls, a embossing with a rotating screen roll by vacuum force There are various methods such as a method of performing, a hot needle process in which a multilayer film is passed through a perforator (a perforator), and a method of compressing using a marking roll. In the present invention, a resin film supplied from a T die Is bonded to a separately supplied metal plate and embossed.
When embossing is performed by such a method, the temperature of the portion where the roll surface comes into contact with the raw resin film is measured by Tss, which is the softening start temperature measured by TMA, Tse, which is the softening end temperature, and DSC. Using Tmp as a reference, the temperature is set to Tss−10 ≦ Tr ≦ Tse (° C.) and Tr ≦ Tmp (° C.). As the embossed shape, various patterns such as a random mat, a square, a diamond shape, a deep drawing type, and a grain (referred to as SG) can be used according to the needs of the product.

(Embossing quality judgment)
The quality of embossing of the resin film or the like in the present invention is determined by the surface roughness Ra (μm) of the resin film. In general, good embossability means that an embossed pattern is easily formed on the surface of a resin film when it is pressed and embossed with a sculpture roll at a temperature around the melting point of the resin. It means that the embossed pattern is maintained for a time.
Therefore, the measurement of the surface roughness is based on the softening start temperature Tss and the softening end temperature Tse in the temperature rising process measured by TMA of the resin, with Tss-10 ≦ Tr ≦ Tse (° C.) and Tr ≦ Tmp. The resin film is passed at a constant speed through an uneven grain engraving roll having an average surface roughness Ra = 11 mm set at (° C.). In this case, the setting and adjustment of the surface temperature of the roll can be performed by a method in which a certain amount of heat medium is caused to flow through a pipe provided in the roll.
The resin film laminated metal plate is then cooled to room temperature, and the surface roughness Ra (μm) is measured using a SURFCOM surface roughness meter manufactured by Tokyo Seimitsu Co., Ltd. according to JIS B0601, and the average surface roughness is 4. An embossing property of 0 or more was considered good. In this measurement, five resin test pieces are arbitrarily sampled from the resin film that has been subjected to the embossing treatment, and the surface roughness at four different locations is measured for each test piece. Was calculated as the surface roughness Ra (μm).
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples.

(Example 1)
An aluminum-killed cold-rolled steel sheet having a carbon content of 0.030% and a thickness of 0.50 mm was prepared, and this steel sheet was galvanized to a thickness of 0.002 mm. Furthermore, this galvanized steel sheet is heated to a melting point Tmp ± 10 ° C. of the resin, and is a PBT (polybutylene terephthalate) resin film having a thickness of 0.100 mm on the surface, and its intrinsic viscosity is 1.4. A laminated steel sheet was produced by thermocompression bonding of a resin film having a relational value of 7.2. Next, while adjusting the surface temperature of the embossing roll to 215 ° C., the embossing treatment is performed by simultaneously pressing the steel plate and the resin using a stamping roll having a grained pattern, and then suddenly reaching room temperature. Cooled down. The average surface roughness Ra for evaluating the embossability of the resin film on the steel sheet thus treated was 6.7 μm.

(Examples 2 to 4)
By changing the type of resin, the same laminated steel plate as in Example 1 was prepared, and the temperature of the roll was set based on the values of Tss by TMA of the resin used, Tse which is the softening end temperature, Tmp by DSC, etc. The embossing process was performed and the embossability was evaluated.
Example 2 has an intrinsic viscosity of 1.4 as in Example 1, but a PBT resin having a TMA-related value of 2.9 is used, and Example 3 has an intrinsic viscosity of 1.0 and a TMA-related value. This is a case where a PBT resin having a value of 3.3 was used. In Example 4, a 10 mol% copolymer resin film of polyethylene terephthalate (PET) and isophthalic acid and a polybutylene terephthalate (PBT) resin film were used in a ratio of 1: 4. This is a case where a multilayer film (TMA related value: 8.7) laminated at a thickness ratio is used so that the PBT layer is in contact with the engraving roll.

(Comparative Examples 1 and 2)
By further changing the type of resin, the same laminated steel plate as in Example 1 was produced, and the roll temperature was set based on the Tss by TMA of the resin used, Tse which is the softening end temperature, and Tmp by DSC. Then, an embossing treatment was performed to evaluate the embossing property. Comparative Example 1 is a case where a PET resin having a TMA-related value of 22.8 is used, and Comparative Example 2 is a case where a polycarbonate resin having a TMA-related value of 18.9 is used. Table 1 shows the conditions and measured values of these examples and comparative examples.
In order to examine the presence or absence of a high-quality feeling for the sample obtained as described above, the following test was performed. First, three laminated steel sheets cut to a size of 30 × 20 cm are prepared, placed on a room table where sunlight does not enter, and irradiated with five 20 W white fluorescent lamps from 1 m above the sample. Five people with different ages and genders are given the following evaluation points by changing the observation place and angle, and the average value of the evaluation points is obtained and comprehensively evaluated.
The evaluation score is 5 points when there is a high-grade feeling equal to or higher than that of the conventional PVC-laminated steel sheet, 4 points when it is slightly inferior to the PVC-laminated steel sheet, but a slightly high-grade feeling is obtained. Three points are given for the feeling of being cheap compared to the laminated steel plate.
When such an evaluation is performed, there is a correlation with the surface roughness, and a TMA-related value of 10 or less is used, and the roll temperature Tr is set to the softening start point Tss and the softening end point Tse by TMA. Samples of Examples 1 to 4 processed using Tss-10 ≦ Tr ≦ Tse (° C.) and set to a temperature of Tr <Tmp (° C.) using Tmp by DSC. Both were judged to have a sufficient luxury. On the other hand, in the case of the samples of comparative examples that do not match these requirements, no high-class feeling was obtained.
INDUSTRIAL APPLICABILITY The resin film of the present invention has an embossing property equivalent to or better than that of a conventional soft vinyl chloride resin, and the decorative metal plate coated with the resin film is a high-quality and sensitive resin. It is a coated metal plate. The decorative metal plate of the present invention is a material suitable for use in building materials, industrial materials, and the like that require relatively water resistance, such as unit baths, water supply tanks, various industrial products, and cans.

It is an example of the measurement curve of a TMA relation value.

Claims (3)

A resin film excellent in embossability, wherein a TMA-related value given by the following formula is 10 or less.
TMA-related value (° C.) = Tse−Tss where Tss (° C.) is a softening start temperature measured by TMA Tse (° C.) is a softening end temperature measured by TMA. After the resin film of claim 1 is coated on a decorative metal plate, the surface temperature Tr of the portion where the roll comes into contact with the resin film is measured by TMA when embossing is performed by a rolling process using an engraving roll. The embossing process is performed by setting Tss−10 ≦ Tr ≦ Tse (° C.) and Tr <Tmp (° C.) with reference to the starting temperature Tss, the softening end temperature Tse, and Tmp measured by DSC. The embossing method characterized by the above-mentioned. A decorative metal plate coated with the resin film of claim 1 or the processed film of claim 2.

Images