JP7052307B2 - Laminated white polyester film and recorded material - Google Patents

Description

The present invention relates to a laminated white polyester film. More specifically, the present invention relates to a laminated white polyester film suitable as a recording material, which is an information printing medium that replaces paper such as copy paper.

Currently, with the increasing performance of copiers and printing printers, these devices are used for various purposes and forms such as printing and copying documents, printing photographs and videos, and issuing forms and slips. It is used for the issuance of. As a result, the consumption of copy paper and printer paper in businesses and homes is increasing.

Since mass consumption of paper including copy paper and printer paper is not desirable from the viewpoint of suppressing deforestation, recycled paper that has been collected, separated into recycled pulp at a paper mill, and recycled has been used. ..
Recycled paper is used paper recovered from its main raw materials, but in order to make recycled paper from the recovered used paper, a certain amount of new wood resources are also required, so it is tentatively recycled paper. Even if the utilization rate of paper increases, wood resources will still be consumed, and the use of recycled paper will not be a drastic solution to protect the forest environment.
In addition, the quality of recycled paper is still inferior to that of high-quality paper, and when copying paper made of recycled paper is used, the whiteness of the paper is reduced and the color is grayish, so the degree of color development when printing is performed. There is a tendency for the image quality to deteriorate.
Further, recycled paper has a problem that it is expensive to manufacture and tends to be more expensive than high-quality paper, so that the actual situation is that the use as a substitute for high-quality paper has not been established.

Instead of such recycled paper, there has been proposed a paper that can reuse the used paper by peeling and removing the image formed on the surface of the paper by an electrophotographic method such as a copying machine. For example, based on paper mainly composed of cellulose fibers, a layer containing a polymer selected from polyvinyl alcohol, starch, carboxymethyl cellulose, polyvinyl acetate, and acrylic resin is provided on the surface of the base on which an image is recorded, and the polymer is provided. A reusable recorded material in which a layer containing a compound having a linear or branched alkyl group or an alkenyl group and having a toner-repellent property is provided on the layer containing the material is disclosed (see, for example, Patent Document 1).
However, since the recorded material has a thin polymer layer in order to reduce the cost of the polymer layer and requires paper for the base, it does not mean that wood resources are not completely used, so that the forest environment is improved. It is not a solution to protect.

Therefore, there is a study of synthetic paper made of plastic as a material completely replaced with paper. For example, synthetic paper made of polypropylene is used for daily necessities. (See, for example, Patent Document 2)

Japanese Unexamined Patent Publication No. 2005-234162 Japanese Unexamined Patent Publication No. 10-204196

However, the synthetic paper described in Patent Document 2 is sensitive to heat, and when used in a copying machine or printer that fixes toner at a relatively high temperature, the synthetic paper melts in the copying machine, causing wrinkles and causing a paper jam. Was likely to occur.

The present invention has been made in view of the above circumstances, and the problem to be solved thereof is that the laminated white material can be used as a recording material which is an information printing medium instead of paper such as copy paper, and is extremely cost effective. The purpose is to provide a polyester film.

The gist of the present invention lies in a laminated white polyester film characterized in that the surface layer contains a polymer incompatible with polyester and the arithmetic mean roughness (SRa) of the surface layer is 950 nm or less.

The laminated white polyester film of the present invention contains a polymer incompatible with polyester in the surface layer, and the arithmetic average roughness (SRa) of the surface layer is 950 nm or less. It is a plastic film that can be used as a recording material as a printing medium and is extremely cost effective. Further, the laminated white film of the present invention can suitably transfer a toner image. That is, the toner image can be suitably transferred by a method such as an electrophotographic method, a thermal transfer method, or an inkjet method in which the toner image is transferred to the recording material. Further, after being used as a recording material, characters and images due to toner and / or an image forming substance formed on the surface can be easily peeled off and removed.

Hereinafter, the present invention will be described in more detail.

<This laminated white polyester film>
The laminated white polyester film (referred to as "the present laminated white polyester film") as an example of the embodiment for carrying out the present invention is a laminated film having at least two or more layers containing polyester as a main component resin. At least the surface layer is characterized by containing a polyester and a polymer incompatible with the polyester.

<Surface layer>
The surface layer of the laminated white polyester film preferably contains at least polyester as a main component resin and a polymer incompatible with polyester.
Here, the "main component resin" means a resin having the highest inclusion ratio among the resin components constituting the surface layer. It can be assumed that the main component resin occupies 30% by mass or more, particularly 50% by mass or more, and 80% by mass or more (including 100% by mass) of the resin components constituting the surface layer.

(polyester)
The polyester constituting the laminated white polyester film refers to a polyester obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol.
Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic glycol include ethylene glycol, diethylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, 1, Examples thereof include 4-cyclohexanedimethanol.

Typical polyesters include polyethylene terephthalate (PET), polyethylene-2,6-naphthalenedicarboxylate (PEN), polybutylene terephthalate and the like.

The polyester may be a homopolymer that is not copolymerized, and 20 mol% or less of the dicarboxylic acid component is a dicarboxylic acid component other than the main component, and / or 20 mol% or less of the diol component is other than the main component. It may be a copolymerized polyester which is a diol component of. It may also be a mixture thereof.

Polyester can be obtained by a conventionally known method, for example, a method of directly obtaining polyester by a reaction of a dicarboxylic acid and a diol, or a method of reacting a lower alkyl ester of a dicarboxylic acid with a diol with a conventionally known transesterification catalyst, and then the presence of a polymerization catalyst. It can be obtained by a method of carrying out a polymerization reaction below. As the polymerization catalyst, known catalysts such as antimony compounds, germanium compounds, titanium compounds and aluminum compounds can be used.

The laminated structure of the present laminated white polyester film may be two layers, three layers, four layers or more layers as long as it does not exceed the gist of the present invention, and is not particularly limited. Above all, a three-layer structure (surface layer / intermediate layer / surface layer) composed of both surface layers and an intermediate layer is preferable.
In addition, the case where the laminated structure is two layers means that it is composed of two surface layers, and specifically, the composition of the polyester constituting each layer and the composition of the contained particles and the like are different. Examples thereof include cases where the layers are formed.

(Polymer incompatible with polyester)
By containing a polymer incompatible with polyester in the laminated white polyester film, innumerable ultrafine cavities can be contained in the polyester film stretched at least in the uniaxial direction. Due to the ultrafine cavities, the laminated white polyester film scatters light and not only brings about white opacity, but also reduces the apparent density of the laminated white polyester film.
Above all, by containing a polymer incompatible with polyester in the surface layer of the laminated white polyester film, when used as a recording material for copy paper or printer paper, toner printed or printed on the surface of the laminated white polyester film, etc. The image-forming substance containing the thermoplastic resin of the above can be easily peeled off and removed. Further, in order to ensure sufficient hiding power and weight reduction, the intermediate layer may contain a polymer incompatible with polyester, if necessary.

As the polymer incompatible with polyester, conventionally known polymers can be used, and examples thereof include polyolefins, polystyrenes, polyacrylic acids, polycarbonates and the like. Among them, polyolefins and polystyrenes are preferable, and polyolefins are particularly preferable. Further, among the polyolefins, polypropylene, polyethylene, poly-4-methylpentene-1, amorphous polyolefin and the like can be mentioned, and among them, polypropylene is more preferable in consideration of the easiness of forming cavities and forming a film.

The above-mentioned polyester contains an incompatible polymer, is extruded into a sheet, and then the sheet is stretched at least in the uniaxial direction to contain ultrafine independent cavities inside the film. At this time, a surfactant, an inert particle, a fluorescent whitening agent, or the like may be blended in order to increase the ultrafineness, concealment, and whiteness of the cavity.

When polypropylene is used as the polymer incompatible with polyester, the laminated white polyester film has a propylene unit content of preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably 90 mol% or more in the polypropylene polymer. It is in the range of 95 mol% or more. For example, by reducing the content of the copolymer obtained by copolymerizing other than the propylene unit and using it within the above range, the formation of fine cavities can be sufficiently sufficient.

When polypropylene is used as a polymer incompatible with polyester, the melt flow index of polypropylene under the conditions of a temperature of 230 ° C. and a load of 2.16 kg (21.2 N) is usually 0.5 ml / 10 minutes or more as a lower limit. The range is preferably 1 ml / 10 minutes or more, more preferably 3 ml / 10 minutes or more, and further preferably 5 ml / 10 minutes or more. In the case of the above range, a sufficient cavity size can be generated, and it is possible to easily avoid breakage during stretching.
On the other hand, the upper limit is usually 50 ml / 10 minutes or less, preferably 40 ml / 10 minutes or less, more preferably 30 ml / 10 minutes or less, and further preferably 25 ml / 10 minutes or less. In the above range, it is possible to avoid the clip coming off during lateral stretching, and it is possible to maintain productivity.

The lower limit of the content of the polymer incompatible with polyester in the surface layer is usually 1% by weight or more, preferably 2% by weight or more, more preferably 3% by weight or more, still more preferably 5% by weight or more, and particularly preferably 8% by weight. % Or more. By using the film within the above range, the amount of fine cavities formed in the film is sufficient, the concealing property of the film is improved, and the effect of reducing the apparent density, that is, the weight reduction is sufficient. In addition, the slipperiness of the film and the writability of pencils and the like are improved, which is advantageous for print transportability. Further, on the surface of the film, characters and images due to printed or printed toner and / or an image forming substance can be easily peeled off, and the film can be repeatedly used as a recording material for copying paper or printer paper. Tend.
On the other hand, the upper limit of the content of the polymer incompatible with polyester in the surface layer is usually 70% by weight or less, preferably 50% by weight or less, more preferably 40% by weight or less, still more preferably 35% by weight or less, and particularly preferably. It is 30% by weight or less, most preferably 25% by weight or less. By using it in this range, the amount of cavities generated is not too large, and it tends to be easy to suppress breakage during stretching.

Further, the lower limit of the content of the polymer incompatible with polyester in each layer of the laminated white polyester film is usually 1% by weight or more, preferably 2% by weight or more, more preferably 3% by weight or more, still more preferably 5% by weight. As mentioned above, it is particularly preferably 8% by weight or more. By using it in the above range, it is possible to have sufficient concealment and to have a sufficient effect of reducing the apparent density, that is, to reduce the weight.
On the other hand, the upper limit of the content of the polymer incompatible with polyester in each layer of the laminated white polyester film is usually 70% by weight or less, preferably 50% by weight or less, more preferably 40% by weight or less, still more preferably 35% by weight. Below, it is particularly preferably 30% by weight or less, and most preferably 25% by weight or less. By using it in this range, the amount of cavities generated is not too large, and it tends to be easy to suppress breakage during stretching.

When the laminated white polyester film has three or more layers, the intermediate layer is a recycled product such as a selvage portion, a master roll ear portion, and a master roll lower winding portion generated during film production, as long as the gist of the present invention is not impaired. It may be blended. By including recycled products, it has the effects of cost reduction and environmental load reduction. The content of the recycled product in the intermediate layer is preferably 95% by weight or less, more preferably 85% by weight or less, in terms of film formation stability due to the decrease in intrinsic viscosity, in addition to the color tone regulation. It is more preferably 70% by weight or less, particularly preferably 60% by weight or less, and most preferably 40% by weight or less.

(Metal compound particles)
It is also possible to include metal compound particles in the laminated white polyester film for the purpose of further improving the hiding property and the whiteness. When the polyester film has three or more layers, it may be a surface layer or an intermediate layer, but it is contained in the surface layer in order to effectively improve the hiding power and the whiteness. It is preferable to do so.

The metal compound particles used in this laminated white polyester film tend to compensate for the white opacity caused by the light scattering effect caused by the fine cavities caused by the incompatible polymer, and therefore have higher hiding power and whiteness. Tend to be obtained. Examples of the metal compound particles used include known titanium oxide, calcium carbonate, barium sulfate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, zirconium oxide and the like. Titanium is suitable.

The average particle size of the metal compound particles used has a lower limit of usually 0.05 μm or more, preferably 0.10 μm or more, more preferably 0.20 μm or more, still more preferably 0.25 μm or more, and an upper limit of usually 0.50 μm or less. It is preferably 0.45 μm or less, more preferably 0.40 μm or less. By using the film within the above range, the degree of concealment when the film is formed becomes sufficient, and the show-through tends to be improved especially when the entire surface is printed on both sides of the film.

Further, the lower limit of the content of the metal compound particles is preferably 1% by weight or more, more preferably 2% by weight or more, still more preferably 3 with respect to the entire surface layer of the present laminated white polyester film containing the metal compound particles. It is usually 30% by weight or less, preferably 20% by weight or less, more preferably 15% by weight or less, still more preferably 13% by weight or less, and particularly preferably 10% by weight or less. By setting the above range, a sufficient degree of concealment can be imparted, which is also advantageous in terms of cost, and it is optimal to use it as a recording material for copying paper or printer paper instead of paper made of paper. It tends to be a thing.

(Particles other than metal compound particles)
In order to improve the handleability and slipperiness of the laminated white polyester film, in particular, the surface layer of the laminated white polyester film contains particles other than the metal compound particles exemplified above for imparting slipperiness. May be good.
Specific examples of the particles other than the metal compound particles exemplified above include silica particles and organic particles. Specific examples of the organic particles include organic particles such as acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin, and benzoguanamine resin. Of these, silica particles are particularly preferable because they are likely to be effective even in a small amount.

The average particle size of the particles (silica particles or organic particles) other than the metal compound particles exemplified above is preferably more than 0.50 μm, more preferably 1.0 μm or more, still more preferably 1.5 μm or more, and particularly preferably 1.5 μm or more. It is 2.0 μm or more. Within the above range, it tends to be possible to impart sufficient slipperiness. The upper limit of the average particle size of the particles is usually 15.0 μm or less, preferably 12.0 μm or less, more preferably 10.0 μm or less, still more preferably 8.0 μm or less. By setting the above range, the surface of the film does not become too rough, characters and images such as toner and / or image forming substances printed or printed on the surface of the film can be easily peeled off and removed, and the film can be printed on copy paper or. It tends to be possible to repeatedly use it as a recording material for printer paper. Further, it is not necessary to make the thickness of the surface layer extremely thick from the surface of particle shedding, and the optimum range of the thickness is wide, which is a preferable form.

The shape of the particles (silica particles or organic particles) other than the metal compound particles exemplified above is not particularly limited, and any of spherical, lumpy, rod-shaped, flat-shaped and the like may be used. Further, the hardness, specific gravity, color and the like are not particularly limited. Two or more kinds of these particles may be used in combination as needed.

The content of particles (silica particles or organic particles) other than the metal compound particles exemplified above cannot be unequivocally determined because it depends on the average particle size, but it can be applied to the entire surface layer of the polyester film containing the silica particles or organic particles. On the other hand, it is usually in the range of 5% by weight or less, preferably 3% by weight or less, more preferably 2% by weight or less, still more preferably 1% by weight or less, and the lower limit of the preferable range is 0.005% by weight or more. It is preferably 0.05% by weight or more, more preferably 0.1% by weight or more. By using the film within the above range, the surface roughness of the film can be made appropriate, and the desired slipperiness can be achieved. In addition to imparting slipperiness, it also makes it easier to peel off and remove characters and images such as toner and / or image forming substances printed or printed on the surface of the film, and the film can be used as a recording material for copying paper or printer paper. It tends to be used repeatedly. Further, as the role of silica particles and organic particles, there is a tendency to further improve the writing property of pencils, mechanical pencils, ballpoint pens and the like.

(Other ingredients)
In addition to the above-mentioned particles and the polymer incompatible with polyester, conventionally known antioxidants, heat stabilizers, lubricants, antistatic agents, and fluorescent whitening agents may be contained in the laminated white polyester film. , Dyes, pigments and the like can be added. Further, depending on the application, an ultraviolet absorber, particularly a benzoxazinone-based ultraviolet absorber or the like may be contained.

(Laminated structure)
As described above, the laminated white polyester film is a laminated film having at least two layers containing polyester as a main component resin, and at least the surface layer thereof contains a polymer incompatible with polyester and is said to be the same. It is a laminated white polyester film characterized by having an arithmetic average roughness (SRa) of 950 nm or less on the surface layer.
If the surface layer contains a polyester and a polymer incompatible with the polyester as described above, fine cavities can be provided by stretching, so that weight reduction, concealment and whitening can be realized. Since the surface roughness can be adjusted, the writing ability can be improved.

If the surface layer further contains metal compound particles, the hiding power and whiteness can be further enhanced, and further, by containing particles other than the metal compound particles, the slipperiness can be improved.

If the intermediate layer other than the surface layer contains the polyester, the polymer, the metal compound particles, and the particles other than the metal compound particles that are incompatible with the polyester may be contained, if necessary. It is preferable that the content of the metal compound particles and the particles other than the metal compound particles is as small as possible, and that polyester as a recycled product is blended and used from the viewpoint of cost reduction and environmental load reduction.

(Thickness)
The thickness of the laminated white polyester film is not particularly limited as long as it can be formed as a film, but is usually 10 to 1000 μm, preferably 20 to 500 μm, more preferably 30 to 400 μm, and particularly preferably 38. It is in the range of ~ 350 μm. By using the film within the above range, it is possible to make the film firm and easy to handle.

In this laminated white polyester film, the content of metal compound particles and particles other than metal compound particles other than the metal compound particles and particles other than the metal compound particles contained in the recycled product is used as small as possible, so that the surface layer is used. It is preferable to contain it. Further, in order to reduce the cost and the environmental load by blending a recycled product in the intermediate layer, it is preferable to form a laminated structure by using a coextrusion method. From this point of view, when the polyester film has a laminated structure of three or more layers as described above, the thickness of each surface layer is preferably 1 μm to 50 μm, particularly 2 μm or more or 40 μm or less, and among them 3 μm or more or 30 μm. Hereinafter, among them, it is more preferably 4 μm or more or 25 μm or less. By using it in the above range, it is possible to fully exhibit the performance of the metal compound particles described later and particles other than the metal compound particles, and the manufacturing cost can be suppressed at a low cost.

(Apparent density)
The lower limit of the apparent density of the laminated white polyester film is usually 0.7 g / cm ³ or more, preferably 0.75 g / cm ³ or more, and more preferably 0.8 g / cm ³ or more. Within the above range, the strength of the film can be maintained, and clogging of the film in the transport process in the copier can be reduced when it is used as a recording material in place of the copy paper or printer paper which is an information printing medium. It is possible to perform optimum printing and printing.
On the other hand, the upper limit is usually 1.3 g / cm ³ or less, preferably 1.2 g / cm ³ or less, and more preferably 1.1 g / cm ³ or less. By setting the above range, the work load when carrying a large amount of printed matter is reduced, and it is possible to reduce the environmental load and cost by reducing CO ₂ generated in the film (sheet) transportation process. ..
The apparent density of the polyester film can be adjusted by blending an incompatible polymer having a lighter specific gravity than polyester, which is the main component resin, and stretching at least in the uniaxial direction. However, the method is not limited to these methods.

<Physical characteristics>
The arithmetic mean roughness (SRa) of the surface, that is, the surface layer of the laminated white polyester film is preferably 950 nm or less, more preferably 850 nm or less, and more preferably 800 nm or less. By using the arithmetic average roughness (SRa) in the above range, characters and images such as toner and / or image forming substance containing a thermoplastic resin formed on the film surface by printing or printing can be easily peeled off and removed. There is a tendency that the film can be repeatedly used as a recording material for copying paper and printer paper.
On the other hand, the lower limit of the arithmetic mean roughness (SRa) is preferably 100 nm or more, more preferably 200 nm or more, particularly 300 nm or more, and more preferably 350 nm or more. Within the above range, it is possible to make the film concealing and transportable sufficient, and it is possible to make the film most suitable for use as a recording material for copying paper and printer paper. Furthermore, it tends to have sufficient writability.
The arithmetic mean roughness (SRa) in the present invention is based on the measurement method used in the examples described later.

The b value (reflection method), which is an index indicating the yellowness of the laminated white polyester film, is usually 0.00 or less, preferably -0.20 or less, more preferably -0.40 or less, still more preferably -0. It is 50 or less, particularly preferably −0.60 or less, and the lower limit is not particularly limited, but −5.0 or more is preferable. By using it in the above range, yellowness can be suppressed and whiteness can be improved. Further, when used as a recording material for color printing, the obtained image quality tends to be excellent.

In this laminated white polyester film, the heat shrinkage in the film longitudinal direction (MD) and the film width direction (TD) at 150 ° C. for 30 minutes is usually 2.8% or less, preferably 2.3% or less as an absolute value. More preferably, it is 2.0% or less.
By setting the heat shrinkage rate within the above range, the dimensional stability of the film due to the influence of heat when printing or printing on the recorded material by a method such as an electrophotographic method or a thermal transfer method in which the toner image is transferred to the recorded material. It is possible to prevent the printing from being damaged, and it is possible to suppress the occurrence of wrinkles even in the edge portion of the film (sheet), that is, the portion where wrinkles are likely to occur, and the characters and images are distorted or uneven. Therefore, it is possible to suppress the phenomenon that the image quality deteriorates. Further, since wrinkles cannot be erased once they occur, they cannot be repeatedly used as a recording material for copy paper or printer paper, so it is preferable to prevent wrinkles from occurring as much as possible.

The hiding power (OD) of the laminated white polyester film is usually 0.30 or more, preferably 0.35 or more, more preferably 0.40 or more, still more preferably 0, as measured by a Macbeth densitometer. It is .45 or more. By using it within the above range, show-through when printing on the entire surface is reduced on both sides of the film, and high-quality characters and images can be obtained. On the other hand, the upper limit of the concealing property (OD) is not particularly limited, but in consideration of the balance of other physical properties, 1.0 or less is preferable, and 0.9 or less is more preferable.

The whiteness of this laminated white polyester film is measured by measuring the hunter whiteness (Wb) of a single film with a colorimeter, and the lower limit is usually 80.0% or more, preferably 81.0% or more, more preferably. Is 82.0% or more, more preferably 83.0% or more, and particularly preferably 83.5% or more. By setting the whiteness within the above range, characters and images are high-definition when used as a recording material for copy paper or printer paper, which is an information printing medium instead of paper, especially when color printing is performed. It tends to be preferable in terms of quality. Further, since it depends on the intended use, a higher value is preferable in order to give a high-class feeling, and the upper limit is not particularly limited. On the other hand, when used for applications where gloss is a concern, the upper limit of the preferable range is 95.0% or less.

<Functional layer>
A functional layer may be provided on at least one side of the laminated white polyester film.
The functional layer preferably has antistatic performance and mold release performance.
In this laminated white polyester film, the apparent density is reduced, whitening is performed at no cost, and characters and images such as a toner and / or an image forming substance containing a printed or printed thermoplastic resin are printed on the laminated white polyester film. In order to realize that it can be easily peeled off and removed, it is preferable to provide a polyester resin layer containing a polyester and a polymer incompatible with the polyester, and it is more preferable that the polyester resin layer is provided on the surface layer. However, when the functional layer is provided, it has been found that it tends to be difficult to exhibit the performance of easily peeling off and removing characters and images such as toner and / or image forming substances contained in the surface layer. It is preferable that the layer also has a mold release performance.

This laminated white polyester film can be used as a recording material for copying paper or printer paper that can suitably transfer a toner image by a method such as an electrophotographic method or a thermal transfer method that transfers a toner image to a recording material. The purpose is to prevent double feeding in the paper transport of the machine and to prevent the paper from sticking to each other when handling the paper. Further, in order to prevent the adhesion of dust and to obtain a film having good quality or a film printed matter having good image quality, it is preferable to have a functional layer containing an antistatic agent on at least one side.

Further, the functional layer has a mold release performance so that characters and image-forming substances such as toner containing a thermoplastic resin formed on the film surface can be appropriately peeled off and removed after printing or printing. It is preferable to contain a mold release agent in order to provide the above.

Further, in order to improve the ease of forming an image-forming substance and the adhesiveness of the functional layer, and to improve the wettability to the base film when the functional layer is provided by coating, the functional layer is made of a polymer. It is preferable to contain (a polymer other than the above-mentioned antistatic agent and mold release agent).

The functional layer contains an antistatic agent, a mold release agent, and a polymer to impart appropriate mold release performance, thereby adhering a toner and / or an image forming substance or the like to the film surface, and the toner and / or. It has been found that the function of peeling and removing an image forming substance or the like can be obtained more appropriately. That is, we have found a method to realize the contradictory properties of adhesiveness and peelability with one functional layer at a higher level. It can be said that this technology is extremely effective considering that the peeling performance cannot be realized in the functional layer having general peeling performance, while the adhesive performance cannot be realized in the functional layer having general peeling performance. .. Further, even if the functional layer having the adhesive performance and the functional layer having the peeling performance are laminated, neither of the performances can be exhibited, and only the performance of the functional layer corresponding to the outermost layer is reflected.

Even when the laminated polyester film has the functional layer, the preferable ranges of the b value, the heat shrinkage rate, the concealing property (OD), and the whiteness of the laminated polyester film are the same as the above-mentioned numerical ranges. ..

<Manufacturing method>
Hereinafter, the method for producing the laminated white polyester film will be specifically described, but the present invention is not particularly limited to the following examples as long as the gist of the present invention is satisfied.

First, a raw material blended for each layer that has been dried or undried by a known method is supplied to each melt extruder, heated to a temperature equal to or higher than the melting point of each polymer, and melt-kneaded. The molten polymer in each layer is then guided to the die, usually via a multi-manifold or feed block, and laminated.
Next, the molten sheet extruded from the die is rapidly cooled and solidified on a rotary cooling drum so as to have a temperature equal to or lower than the glass transition temperature to obtain a substantially amorphous unoriented sheet. In this case, in order to improve the flatness of the sheet, it is preferable to improve the adhesion between the sheet and the rotary cooling drum, and the electrostatic application adhesion method and / or the liquid coating adhesion method is preferably adopted.

The sheet obtained as described above is stretched to form a film. The ultrafine independent cavities contained in the polyester film are created by such stretching.

Specifically, the stretching conditions are described. The unstretched sheet is preferably stretched 2.5 to 5 times in the longitudinal direction (longitudinal direction) at 70 to 150 ° C. to form a longitudinal uniaxially stretched film, and then in the width direction (longitudinal direction). Laterally) stretched 3 to 5 times at 70 to 160 ° C., usually in the range of 200 to 250 ° C., preferably 210 to 240 ° C., more preferably 215 to 240 ° C., usually for 5 to 600 seconds, preferably 8 It is preferable to perform heat treatment for about 300 seconds.

The conditions of the heat treatment step affect not only the heat shrinkage rate of the film but also the arithmetic mean roughness (SRa) of the surface layer of the film. That is, by setting the high temperature in the above range, the ultrafine cavities formed by the polymer incompatible with the polyester existing on the surface of the surface layer are dissolved. By appropriately reducing the surface roughness, it becomes possible to easily peel off and remove characters and images such as toner and / or image forming substances containing a thermoplastic resin formed on the film surface by printing or printing. .. As a result, the film can be repeatedly used as a recording material for copy paper and printer paper.

After the heat treatment step, a method of relaxing 2 to 20% in the vertical direction and / or the horizontal direction in the maximum temperature zone of the heat treatment and / or the cooling zone of the heat treatment outlet is preferable. It is also possible to add re-longitudinal stretching and re-transverse stretching as needed.

The method of forming the functional layer on the laminated white polyester film will be described below. The functional layer can be provided by various known methods such as a coating method, a coextrusion method, and a transfer method. Among them, coating is preferable from the viewpoint of efficient production and performance imparting.

As the coating method, the film surface may be treated during the film forming process of the polyester film, which may be provided by in-line coating, or an offline coating may be adopted, which is applied outside the system on the once produced film. .. More preferably, it is formed by in-line coating.

The in-line coating is a method of coating in the process of manufacturing a polyester film, and specifically, a method of coating at an arbitrary stage from melt extrusion of polyester to stretching, heat fixing and winding. Usually, it is coated on any of an unstretched sheet obtained by melting and quenching, a stretched uniaxially stretched film, a biaxially stretched film before heat fixing, and a film after heat fixing and before winding. Although not limited to the following, for example, in sequential biaxial stretching, a method of coating a uniaxially stretched film stretched in the longitudinal direction (longitudinal direction) and then stretching in the lateral direction is particularly excellent. According to such a method, since the film formation and the functional layer formation can be performed at the same time, there is an advantage in manufacturing cost, and the thickness of the functional layer can be changed by the draw ratio in order to perform stretching after coating. , Thin film coating can be performed more easily than offline coating. Further, by providing the functional layer on the film before stretching, the functional layer can be stretched together with the base film, whereby the functional layer can be firmly adhered to the base film. Furthermore, in the production of biaxially stretched polyester film, the film can be restrained in the vertical and horizontal directions by stretching while gripping the end of the film with a clip or the like, and in the heat fixing step, a flat surface without wrinkles or the like. High temperature can be applied while maintaining the sex. Therefore, since the heat treatment applied after coating can be set to a high temperature which cannot be achieved by other methods, the film-forming property of the functional layer can be improved, and the functional layer and the base film can be more firmly adhered to each other. Furthermore, it is possible to form a strong functional layer, prevent the functional layer from falling off, and improve antistatic performance and mold release performance.

<Toner and / or image-forming substance>
Characters and images containing a thermoplastic resin such as toner and / or an image forming substance are provided on the surface of the laminated white polyester film on which the functional layer is not provided or on the surface on which the functional layer is provided. It is possible.
Characters and images can be provided by a conventionally known method, and can be obtained by printing or printing with a copying machine or a printer. Also, conventionally known materials can be used for thermoplastic resins such as toner and / or image forming substances.

<Resin layer>
In this laminated white polyester film, it is possible to further provide a resin layer on characters and images containing a thermoplastic resin such as toner and / or an image forming substance.
The resin layer may be provided to remove characters and images from the film together with the resin layer in order to reuse the laminated white polyester film and the like.

As the resin layer, a conventionally known material can be used, and a curable resin layer is preferable.
Examples of the curable resin layer include a thermosetting resin layer and an active energy ray-curable resin layer. An active energy ray-curable resin layer is preferable from the viewpoint that it is easy to peel off and remove all characters and images.

Examples of the active energy ray-curable resin layer include an ultraviolet curable resin layer, an electron beam curable resin layer, a visible light curable resin layer, and the like, but in consideration of ease of handling and curable performance, ultraviolet curable It is preferably a sex resin layer. As an example of the active energy ray curable resin layer, for example, a hard coat layer can be mentioned.

The material used for the active energy ray-curable resin layer is not particularly limited, and for example, a cured product such as a reactive silicon compound such as a monofunctional (meth) acrylate, a polyfunctional (meth) acrylate, or a tetraethoxysilane is used. Can be mentioned. Of these, from the viewpoint of achieving both productivity and hardness, a polymerized cured product of a composition containing an active energy ray-curable (meth) acrylate is particularly preferable.

The composition containing the active energy ray-curable (meth) acrylate is not particularly limited. For example, a mixture of one or more known active energy ray-curable monofunctional (meth) acrylates, bifunctional (meth) acrylates, and polyfunctional (meth) acrylates, and commercially available resin materials for active energy ray-curable hard coats. In addition to these, those having other components added may be used as long as the object of the present embodiment is not impaired.

The active energy ray-curable monofunctional (meth) acrylate is not particularly limited. For example, alkyls such as methyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate. (Meta) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, etc. Hydroxyalkyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, methoxypropyl ( Acrylic alkyl (meth) acrylates such as meth) acrylates and ethoxypropyl (meth) acrylates, aromatic (meth) acrylates such as benzyl (meth) acrylates, phenoxyethyl (meth) acrylates and phenoxypropyl (meth) acrylates, and diaminoethyl ( Amino group-containing (meth) acrylates such as meth) acrylates and diethylaminoethyl (meth) acrylates, methoxyethylene glycol (meth) acrylates, phenoxypolyethylene grease (meth) acrylates, phenylphenol ethyleneoxide-modified (meth) acrylates and other ethylene oxides. Examples thereof include modified (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, and (meth) acrylic acid.

The active energy ray-curable bifunctional (meth) acrylate is not particularly limited. For example, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonandiol di (meth) acrylate, tricyclodecandy. Alcandiol di (meth) acrylate such as methylol di (meth) acrylate, bisphenol-modified di (meth) acrylate such as bisphenol A ethylene oxide-modified di (meth) acrylate, bisphenol F ethylene oxide-modified di (meth) acrylate, polyethylene glycol di. Examples thereof include (meth) acrylate, polypropylene glycol di (meth) acrylate, urethane di (meth) acrylate, and epoxy di (meth) acrylate.

The active energy ray-curable polyfunctional (meth) acrylate is not particularly limited. For example, dipentaerythritol hexa (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, isocyanuric acid ethylene oxide-modified tri. (Meta) acrylate, isocyanuric acid-modified tri (meth) acrylate such as ε-caprolactone-modified tris (acroxyethyl) isocyanurate, pentaerythritol triacrylate hexamethylenediisocyanate urethane prepolymer, pentaerythritol triacrylate toluenediisocyanate urethane prepolymer, di Examples thereof include urethane acrylates such as pentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer.

The other components contained in the composition containing the active energy ray-curable (meth) acrylate are not particularly limited. Examples thereof include inorganic or organic fine particles, polymerization initiators, polymerization inhibitors, antioxidants, antistatic agents, dispersants, surfactants, light stabilizers and leveling agents. Further, in the case of drying after forming a film in the wet coating method, an arbitrary amount of solvent can be added.

For indoor use such as offices, it is preferable that it does not contain a solvent. As the resin (resin liquid) for forming the resin layer, the content of the solvent is preferably 10% by weight or less, more preferably 5% by weight or less, still more preferably 3% by weight or less, and particularly preferably 1% by weight or less. It is in the range of, and most preferably, it does not contain a solvent (intentionally does not contain it).

Examples of the method for forming the resin layer include a general wet coating method such as a roll coating method and a die coating method, and an extrusion method. The formed resin layer can be heated or irradiated with active energy rays such as ultraviolet rays and electron beams as needed to carry out a curing reaction.

<Explanation of words and phrases>
In the present invention, when "X to Y" (X and Y are arbitrary numbers) is described, it means "X or more and Y or less" and "preferably larger than X" or "preferably Y". It also includes the meaning of "smaller".
Further, when described as "X or more" (X is an arbitrary number), it includes the meaning of "preferably larger than X" and is described as "Y or less" (Y is an arbitrary number). In this case, unless otherwise specified, it also includes the meaning of "preferably smaller than Y".

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded. The measurement method used in the present invention is as follows. The various physical properties in the present invention, their measurement methods, and their definitions are as follows.

<Measurement method>
(1) Intrinsic viscosity of polyester 1 g of polyester from which other polymer components and pigments incompatible with polyester have been removed is precisely weighed, and 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio) is added and dissolved. , Measured at 30 ° C.

(2) Melt flow index (MFI)
According to JIS K7210-1995, it was measured at 275 ° C. and 21.2N for amorphous polyolefin and at 230 ° C. and 21.2N for crystalline polypropylene. The higher this value, the lower the melt viscosity of the polymer.

(3) Arithmetic mean roughness (SRa)
The surface of the laminated white polyester film is surfaced using a non-contact surface / layer cross-sectional shape measurement system VertScan (registered trademark) R550GML manufactured by Ryoka System Co., Ltd., CCD camera: SONY HR-50 1/3', objective lens: 20 Magnification, lens barrel: 1X Body, zoom lens: No Release, wavelength filter: 530 white, measurement mode: Wave, measuring a region of 640 μm × 480 μm, and using the output by 4th-order polymorphic correction, arithmetic average roughness. The SRa value was obtained by averaging 10 points.

(4) Average particle size of particles The size of particles was measured by the sedimentation method based on Stokes's resistance law using a centrifugal sedimentation type particle size distribution measuring device SA-CP3 manufactured by Shimadzu Corporation. The average particle size was taken using the value of 50% of the integrated (volume basis) in the equivalent spherical distribution of the particles obtained by the measurement.

(5) Heat shrinkage rate The sample was treated in an oven maintained at 150 ° C. in a non-tensioned state for 30 minutes, the length of the sample before and after that was measured, and the heat shrinkage rate was calculated by the following formula.
Heat shrinkage rate (%) = {(L0-L1) / L0} × 100
(In the above formula, L0 is the sample length before the heat treatment, and L1 is the sample length after the heat treatment).
Five points were measured in each of the film longitudinal direction (MD) and the width direction (TD), and the average value in each direction was obtained.

(6) Hunter whiteness Using a colorimeter NDH-1001DP (C light source, 2 ° field) manufactured by Nippon Denshoku Industries Co., Ltd., according to the method of JIS P8123-1961, the hunter whiteness when a single film is used ( Wb) was measured. The back surface of the film was pressed with a black plate.

(7) b value (reflection method)
Using a colorimeter NDH-1001DP (C light source, 2 ° field of view) manufactured by Nippon Denshoku Industries Co., Ltd., the b value of a single film was measured according to the method of JIS Z-8722, 8730. The back surface of the film was pressed with a black plate.

(8) Concealment degree (OD)
A Macbeth densitometer TD-904 was used to measure the transmitted density by white light. Five points were measured, and the average value was taken as the OD value. The larger this value is, the lower the light transmittance is.

(9) Apparent density (g / cm ³ )
A 10 cm × 10 cm square sample was cut out from an arbitrary part of the film, and the thickness was measured evenly at 9 points with a micrometer. The weight per unit volume was calculated from the average value and the weight of the film, and used as the apparent density. The number of measurements was 5 points, and the average value was used.

(10) Thickness of Laminated White Polyester Film A small piece of film was fixedly molded with an epoxy resin, cut with a microtome, and the cross section of the film was observed by a transmission electron micrograph. Two of the cross sections are almost parallel to the film surface, and the interface is observed by light and dark. The distance between the two interfaces and the film surface was measured from 10 photographs, and the average value was taken as the thickness of the laminated white polyester film.

(11) Appropriate image quality by electrophotographic printing Ricoh Co., Ltd. multifunction device: A4 size cut film (sheet) is fed into imagioMPC5001it, and a full-color test image on which an image forming substance by photographic printing is placed is printed. Obtained. The image quality was evaluated as follows.
(Evaluation criteria)
A: High-definition, high-quality image quality without wrinkles on the film B: Part of the image quality is slightly unclear, but there is no problem in practical use C: Wrinkles are generated on the film, and the image quality is also unclear and overall. Inferior

(12) Ultraviolet curable resin (2-hydroxy-3-phenoxypropyl acrylate) is 95 parts by weight on the surface of the film on which the image-forming substance obtained in (11) is fixed. A mixture consisting of 5 parts by weight of a photopolymerization initiator (trade name: Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) is uniformly applied, a glass plate is placed on the mixture, and ultraviolet rays are irradiated from above to cure the mixture. A sex resin layer was formed. Then, the glass plate and the film were peeled off. At this time, the formed ultraviolet curable resin layer adheres to the glass plate side, and characters and images made of toner and / or an image forming substance formed on the film surface can be transferred and held. The following evaluations were made on the character and image peeling removal state on the film surface at this time.
(Evaluation criteria)
A: The image-forming substance on the film surface can be completely removed, and it can be used repeatedly as copy paper.
B: Although a small amount of image-forming substance remains on the film surface, it can be used repeatedly as copy paper, and there is no problem in practical use.
C: Most of the image-forming substance remains on the film surface, and it cannot be used repeatedly as copy paper.

(13) Writability
Five straight lines were drawn at 1 mm intervals with a uni-hardness H pencil manufactured by Mitsubishi Pencil Co., Ltd., and the following evaluation was performed visually.
(Evaluation criteria)
A: Individual straight lines can be discriminated.
B: The color of the lines is light and it is difficult to distinguish individual lines.
C: I can't draw a straight line.

[Example 1]
As an intermediate layer, a mixed raw material obtained by mixing 80 parts by weight of polyethylene terephthalate chips having an intrinsic viscosity of 0.67 dl / g and 20 parts by weight of crystalline polypropylene homopolymer chips having a melt flow index of 10 ml / 10 minutes was used at 280 ° C. It was sent to the main twin-screw extruder with vent set in.
As a surface layer, 15 parts by weight of a polyethylene terephthalate chip containing 50% by weight of titanium oxide particles having an average particle size of 0.32 μm and an intrinsic viscosity of 0.66 dl / g, and a crystalline polypropylene having a melt flow index of 8 ml / 10 minutes. A polyethylene terephthalate chip containing 15 parts by weight of a homopolymer chip and 3.5% by weight of silica particles having an average particle size of 4.1 μm and an intrinsic viscosity of 0.66 dl / g is 10 parts by weight and an intrinsic viscosity of 0.69 dl /. The mixed raw material obtained by mixing g polyethylene terephthalate chips at a ratio of 60 parts by weight was sent to a sub-vented twin-screw extruder set at 280 ° C.
Through the gear pump and filter, the polymer from the main extruder is the intermediate layer, and the polymer from the sub extruder is the surface layer. It was extruded and rapidly cooled and solidified on a cooling roll whose surface temperature was set to 30 ° C. using an electrostatic application adhesion method to obtain an unstretched sheet having a thickness of 887 μm.
The obtained unstretched sheet was stretched 3.1 times at 92 ° C. in the vertical direction, then guided to a tenter, then stretched 3.8 times at 120 ° C. in the horizontal direction, and then heat-treated at 235 ° C. for 10 seconds. A biaxially oriented laminated white polyester film having a thickness of 6 μm (surface layer) / 62 μm (intermediate layer) / 6 μm (surface layer) and a total thickness of 74 μm was obtained by relaxing 10% in the lateral direction.
When the obtained laminated white polyester film was evaluated, the image quality appropriateness, characters, image peeling removal appropriateness, and writability were all good. The characteristics of this film are shown in Tables 2 and 3 below.

[Example 2]
As an intermediate layer, 40 parts by weight of a polyethylene terephthalate chip having an intrinsic viscosity of 0.63 dl / g and 15 parts by weight of a crystalline polypropylene homopolymer chip having a melt flow index of 7 ml / 10 minutes were generated during the production of polyester of Example 1. A biaxially oriented laminated white polyester film having a thickness of 75 μm was obtained in the same manner as in Example 1 except that a mixed raw material in which recycled products from the ears and master roll ears were mixed at a ratio of 45% by weight was used. The thickness of each layer of the obtained film was 6 μm / 63 μm / 6 μm. The total amount of polypropylene derived from the crystalline polypropylene homopolymer chip and the recycled product in the intermediate layer was 24% by weight.
When the obtained laminated white polyester film was evaluated, the image quality appropriateness, characters, image peeling removal appropriateness, and writability were all good. The characteristics of this film are shown in Tables 2 and 3 below.

[Example 3]
As an intermediate layer, 3 parts by weight of a polyethylene terephthalate chip having an intrinsic viscosity of 0.66 dl / g and 10 parts by weight of a crystalline polypropylene homopolymer chip having a melt flow index of 10 ml / 10 minutes were generated during the production of polyester of Example 1. A biaxially oriented laminated white polyester film having a thickness of 75 μm was obtained in the same manner as in Example 1 except that a mixed raw material in which recycled products from the ears and master roll ears were mixed at a ratio of 87% by weight was used. The thickness of each layer of the obtained film was 6 μm / 63 μm / 6 μm.
When the obtained laminated white polyester film was evaluated, the characters, image peeling removal appropriateness, and writability were all good. The characteristics of this film are shown in Tables 2 and 3 below.

[Example 4]
As a surface layer, 15 parts by weight of a polyethylene terephthalate chip having an intrinsic viscosity of 0.66 dl / g containing 50% by weight of titanium oxide particles having an average particle size of 0.12 μm, and a crystalline polypropylene homopolymer having a melt flow index of 8 ml / 10 minutes. Polyethylene terephthalate with an intrinsic viscosity of 0.66 dl / g containing 3.5% by weight of silica particles with an average particle size of 4.1 μm and 15 parts by weight of the chip. Polyethylene terephthalate with an intrinsic viscosity of 0.69 dl / g. A biaxially oriented laminated white polyester film having a thickness of 75 μm was obtained in the same manner as in Example 1 except that the mixed raw materials mixed at a ratio of 60 parts by weight of the chips were used. The thickness of each layer of the obtained film was 6 μm / 63 μm / 6 μm.
When the obtained laminated white polyester film was evaluated, the characters, image peeling removal appropriateness, and writability were all good. The characteristics of this film are shown in Tables 2 and 3 below.

[Example 5]
As a surface layer, 15 parts by weight of a polyethylene terephthalate chip containing 50% by weight of titanium oxide particles having an average particle size of 0.32 μm and an intrinsic viscosity of 0.66 dl / g, and a crystalline polypropylene homomer having a melt flow index of 8 ml / 10 minutes. A polyethylene terephthalate chip containing 1.3 parts by weight of a polymer chip and 0.5% by weight of silica particles having an average particle size of 4.1 μm and having an intrinsic viscosity of 0.66 dl / g is 1.6 parts by weight and has an intrinsic viscosity of 0. A biaxially oriented laminated white polyester film having a thickness of 74 μm was obtained in the same manner as in Example 2 except that a mixed raw material in which .69 dl / g of polyethylene terephthalate chips were mixed at a ratio of 82.1 parts by weight was used. The thickness of each layer of the obtained film was 6 μm / 62 μm / 6 μm.
When the obtained laminated white polyester film was evaluated, the image quality was good. The characteristics of this film are shown in Tables 2 and 3 below.

[Example 6]
As a surface layer, 15 parts by weight of a polyethylene terephthalate chip containing 50% by weight of titanium oxide particles having an average particle size of 0.32 μm and an intrinsic viscosity of 0.65 dl / g, and a crystalline polypropylene homomer having a melt flow index of 8 ml / 10 minutes. 10 parts by weight of a polyethylene terephthalate chip containing 0.5 parts by weight of a polymer chip and 3.5% by weight of silica particles having an average particle size of 4.1 μm and an intrinsic viscosity of 0.66 dl / g, and an intrinsic viscosity of 0.68 dl. A biaxially oriented laminated white polyester film having a thickness of 75 μm was obtained in the same manner as in Example 2 except that a mixed raw material in which / g polyethylene terephthalate chips were mixed at a ratio of 74.5 parts by weight was used. The thickness of each layer of the obtained film was 6 μm / 63 μm / 6 μm.
When the obtained laminated white polyester film was evaluated, the image quality was good. The characteristics of this film are shown in Tables 2 and 3 below.

[Comparative Example 1]
As a surface layer, 15 parts by weight of a polyethylene terephthalate chip having an intrinsic viscosity of 0.66 dl / g containing 50% by weight of titanium oxide particles having an average particle size of 0.32 μm, and a crystalline polypropylene homopolymer having a melt flow index of 8 ml / 10 minutes. Except for the use of a mixed raw material mixed at a ratio of 70 parts by weight of a polyethylene terephthalate chip having an intrinsic viscosity of 0.66 dl / g containing 5.0% by weight of silica particles having an average particle size of 11.1 μm and 15 parts by weight of the chip. Obtained a biaxially oriented laminated white polyester film having a thickness of 75 μm in the same manner as in Example 2. The thickness of each layer of the obtained film was 6 μm / 63 μm / 6 μm.
As shown in Tables 2 and 3 below, the obtained laminated white polyester film had poor character and image peeling removal suitability.

[Comparative Example 2]
In the heat treatment step in the film forming step, the thickness is 75 μm and the thickness of each layer is 6 μm / 63 μm / 6 μm in the same manner as in Example 2 except that the heat treatment temperature is 201 ° C. for 10 seconds. Obtained a polyester film.
As shown in Tables 2 and 3 below, the obtained laminated white polyester film had poor image quality suitability and character and image peeling removal suitability.

Claims (6)

After fixing the toner and / or the image-forming substance on the laminated white polyester film by electrophotographic printing, a resin layer is formed on the laminated white polyester film, and then the toner and / or the image-forming substance is applied together with the resin layer. A method for removing toner and / or an image-forming substance, which is peeled off from a laminated white polyester film.
The resin layer is an active energy ray-curable resin layer, and after the resin layer is cured by irradiating the resin layer with active energy rays, the toner and / or the image-forming substance is applied together with the resin layer to the laminated white polyester film. A method of removing a toner and / or an image-forming substance, which is peeled off from the material. The method for removing a toner and / or an image-forming substance according to claim 1, wherein the surface layer of the laminated white polyester fill contains metal compound particles. The method for removing a toner and / or an image-forming substance according to claim 2, wherein the surface layer of the laminated white polyester film contains particles other than the metal compound particles. The method for removing a toner and / or an image-forming substance according to any one of claims 1 to 3, wherein the surface layer contains 1% by weight or more of a polymer incompatible with the polyester of the laminated white polyester film. The method for removing a toner and / or an image-forming substance according to any one of claims 1 to 4, wherein the resin layer contains an active energy ray-curable resin. The method for removing a toner and / or an image-forming substance according to claim 5, wherein the active energy ray-curable resin contains an active energy ray-curable (meth) acrylate.