JP2005193471A - Manufacturing method of composite resin sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a composite resin sheet constituted so as to form a protective layer and an antireflection layer or an antistatic layer on the surface of a resin sheet without damaging appearance and design properties. <P>SOLUTION: In the manufacturing method of the extruded composite sheet comprising a thermoplastic resin, the surface temperature of the thermoplastic resin sheet molded by the sheet die of an extruder is cooled to Tg+10°C or below and a transfer film, which is constituted by successively forming a thin film layer A comprising a cured resin and an adhesive layer B on the surface of a base film having mold releasability, is subsequently supplied to bond one side or both sides of the resin sheet and the adhesive layer B. In this case, the surface of the resin sheet is heated to a range of Tg+10°C to Tg+70°C and bonded under pressure before the base film is removed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to surface modification of resin sheets, and is required for resin sheets used in the fields of electrical and electronic products, automotive interior and exterior parts, interior and exterior building materials, displays, etc. Surface protection performance such as solvent resistance is imparted continuously and stably during extrusion sheet production without impairing the appearance and design of the resin sheet. The present invention relates to an extruded composite sheet that imparts antireflection and antistatic performances that are strongly demanded in the field of use of transparent resins represented by face plates and partition plates.

Conventionally, surface modification of a resin sheet has been carried out by preparing a resin sheet original plate and forming a surface layer having functions such as scratch resistance by secondary processing such as coating and vapor deposition.
Conventionally, a technique for forming a coating film obtained by curing an acrylate-based monofunctional or polyfunctional monomer with an electron beam on the surface of a plastic molding or the like to provide scratch resistance and contamination resistance has been disclosed. In addition to applying the resin composition to the article as a coating, it has been shown to be applied to a film and attached to the article with an adhesive layer attached to the opposite side, or used as the outermost layer of a transfer layer, No specific conditions regarding the transfer method are shown (for example, see Patent Document 1). In addition, a technique for improving the scratch resistance and solvent resistance by forming a cured coating layer of an organosiloxane resin on the surface of a resin sheet is disclosed (for example, see Patent Document 2).

These technologies generally require pretreatment such as cleaning, drying, and ground treatment of the resin sheet original plate, resulting in complicated processes and prevention of dust contamination that impairs appearance and design, For this purpose, it was difficult to implement because large-scale facilities were required.
On the other hand, as a response to continuous production, a surface layer having functions such as scratch resistance, antireflection and antistatic properties is formed on one side of the resin film in advance during extrusion molding of a thermoplastic resin, and an adhesive layer is formed on the other side. There is a method of preparing and continuously laminating a resin film provided with an adhesive layer, and a hard coat film with an adhesive layer that can be used therefor is disclosed (for example, see Patent Document 3). In this case, the pressure-sensitive adhesive layer is affected by so-called environmental changes such as temperature change and humidity change, and is liable to cause appearance defects such as discoloration and peeling after long-term use.

  In addition, many methods have been proposed in which the resin film is made of the same type of resin as the extruded sheet, or a resin with high affinity, and directly laminated to the extruded sheet in the temperature range above the melting temperature without providing an adhesive layer. A method of thermally laminating an acrylic film on a melt-extruded polycarbonate (hereinafter referred to as PC) sheet is disclosed (for example, see Patent Document 4), and the opposite side of the surface of these films laminated on the extruded sheet is disclosed. By forming a surface layer having various functions on the surface, it is possible to obtain an extrusion composite sheet having the intended scratch resistance, antireflection property, antistatic property, etc. When the film is melted, the surface layer having various functions may crack due to the deformation at the time of melting, and the appearance may be impaired, or the expected performance may not be obtained. There are cases, also deformation such as waving the obtained product surface was difficult to avoid a phenomenon that occurs.

Moreover, when laminating using the temperature while the resin is in a molten state, it is necessary to use a film suitable for the melting temperature of the resin, and the selection of the film is limited. Furthermore, since molding of the resin sheet and film lamination are performed at the same time, it is necessary to properly adapt the lamination conditions to the molding conditions of the sheet such as the resin temperature, roll temperature, line speed, etc. There is.
A method of obtaining a decorative material having an antistatic function by pressing a transfer film provided with an antistatic layer in a heated state is shown, and the situation of the extruder is shown as a process diagram of the manufacturing method of this decorative material. Also, no specific conditions are shown (for example, see Patent Document 5).

Japanese Patent Laid-Open No. 5-57235 JP 2001-232728 A Japanese Patent Laid-Open No. 11-309813 JP-A-6-270225 JP-A-5-162230

  An object of the present invention is to provide a method for forming a protective layer, an antireflection layer or an antistatic layer on the surface of a resin sheet easily and stably without impairing the appearance and design of the resin sheet. .

  As a result of intensive studies to solve the problems in the previous period, the present inventors continuously supplied a film on which a thin film layer was formed during extrusion sheet forming, and transferred the thin film layer to the surface of the extruded sheet. However, it has been found that specific conditions are necessary for stable production while maintaining a good appearance and design, and the present invention has been completed.

That is, the present invention
1. A method for producing an extruded composite sheet made of a thermoplastic resin, wherein the surface temperature of a thermoplastic resin sheet formed by an extruder sheet die is cooled to Tg + 10 ° C. or lower, and then a cured resin is formed on a base film surface having releasability When the transfer film formed in the order of the thin film layer A and the adhesive layer B is supplied and the one or both sides of the resin sheet are bonded to the B layer, the surface of the resin sheet is heated in the range of Tg + 10 ° C. to Tg + 70 ° C. , A method for producing an extruded composite sheet, characterized by crimping and then removing the base film,

2. The method for producing an extruded composite sheet according to the above 1, wherein the surface is heat-pressed with a thermocompression-bonding roll having a heat-resistant resin lining on the surface, and then heat-pressed again with a metal thermocompression-bonding roll,
3. 2. The method for producing an extruded composite sheet according to 1 above, wherein after heat-pressing with a thermocompression-bonding roll having a heat-resistant resin lining on the surface, heat-pressing again with a thermocompression-bonding roll sprayed with ceramic on the surface ,
4). The surface is lined with a heat-resistant resin and heat-pressed by a thermocompression-bonding roll heated to a predetermined temperature of 160 ° C. or lower, and then the outer surface is brought to a predetermined temperature within a range of 160 ° C. to 250 ° C. The method for producing an extruded composite sheet according to any one of the above 1 to 4, wherein the heat-compression bonding is performed again with a heated thermocompression-bonding roll,
It is.

In the thermoplastic resin sheet extrusion process, first, a resin sheet is formed by a conventional extrusion method, and after the sheet surface temperature is lowered to Tg + 10 ° C. or less and the resin sheet is solidified, the base film has releasability. On the surface, a transfer film formed in the order of a thin film layer A made of a cured resin and an adhesive layer B is continuously supplied.
The transfer film is pressed against the surface of the resin sheet with a thermocompression-bonding roll, and only the vicinity of the surface of the resin sheet is heated with a thermocompression-bonding roll to Tg + 10 ° C. to Tg + 70 ° C., thereby forming the thin film layer A via the adhesive layer B of the transfer film. Is transferred to at least one surface of a thermoplastic resin extruded sheet, and then the base film is peeled off.

Furthermore, as the thermocompression-bonding roll, a resin-lined surface is provided, and a metal roll is installed on the downstream side thereof to form a thermocompression-bonding roll in two stages, and the transfer film is heated and pressed on the resin sheet. The composite sheet is transferred to at least one side of the resin sheet, and then the base film is peeled off.
Further, instead of the metal thermocompression bonding roll, a ceramic sprayed roll is used on the surface, and the thermocompression bonding roll has a two-stage configuration of a resin lining roll and a ceramic spraying roll, and the transfer film is heated and applied to the resin sheet. It is a method for producing a composite extruded sheet, characterized in that it is pressed and transferred onto at least one surface of a resin sheet, and then the base film is peeled off.

  In the present invention, when a protective layer, an antireflection layer, or an antistatic layer is formed on the surface of a resin sheet to achieve high functionality, rational and stable production is possible by continuous production, and the appearance is good. An extruded composite sheet is provided.

The present invention will be specifically described below.
As a method of transferring the thin film layer formed on the surface of the transfer film to the surface of the thermoplastic resin sheet to form a composite sheet, both are prepared separately, and the press is pressed under appropriate heating conditions and transferred in a batch format. And a method in which when a thermoplastic resin is formed into an extruded sheet, a roll-wrapped transfer film is continuously supplied in the process, and the film is transferred while applying heat and pressure with a roll. Compared to the method of integrating with the above-mentioned hot press, at least the cleaning process of the base sheet is unnecessary, the process is simple, and continuous production is easy, so it is excellent in mass productivity, and it is free from bubbles and dust in the air. A composite sheet having excellent appearance quality substantially free from irregularities due to entrainment and the like can be stably obtained, and is more useful industrially.

Hereinafter, a description will be given with reference to FIG.
In a normal extrusion equipment consisting of an extruder, a sheet die, a polishing roll, and a take-up roll, between the polishing roll 2 and the take-up roll 7, the thermocompression-bonding roll 5 and a position where the surface temperature of the sheet is lowered to Tg + 10 ° C. or less of the resin 6 is installed, and the transfer film 4 is fed out from the roll raw fabric 9. At this time, the film is supplied to the thermocompression-bonding rolls 5 and 6 under tension through the film supply roll 10 and transferred to one side of the extruded sheet.
The thermocompression-bonding rolls 5 and 6 here are rolls having a heating mechanism capable of heating the outer surface to a predetermined temperature.
In addition, it is not preferable that the thermocompression-bonding roll is installed at a position where the surface temperature of the sheet is Tg + 10 ° C. or more of the resin, because the base material is likely to be deformed, warped or poor in appearance.
The temperature of the thermocompression-bonding rolls 5 and 6 is set so that the surface temperature of the resin sheet when passing through the thermocompression-bonding roll is in the range of Tg + 10 ° C. to Tg + 70 ° C. of the resin.

  Generally, the Tg of the adhesive layer of the transfer film used in this method is lower than the Tg of the base resin sheet. For this reason, sufficient adhesion will be acquired if a transfer film and a resin sheet are heated more than Tg of a resin sheet, and are pressurized. However, in this method, since the heating time is momentary when passing through the roll, adhesion between the transfer film and the resin sheet is sufficiently obtained particularly when the line speed is high or the Tg of the film adhesive layer is high. It may not be possible. For this reason, it is preferable to set the temperature of the thermocompression bonding roll so that the sheet surface temperature is Tg + 10 ° C. to Tg + 70 ° C. Further, in the case of a thin sheet having a resin sheet thickness of less than 2 mm, even when the sheet surface temperature is Tg + 50 ° C. or higher, deformation of the substrate, warpage, or poor appearance may occur even within the above temperature range. is there. For this reason, when the thickness of the resin sheet is a thin plate of less than 2 mm, it is more preferable that the resin sheet is set to have a range of Tg + 10 ° C. to Tg + 40 ° C.

When the surface temperature of the resin sheet when passing through the thermocompression-bonding roll is lower than the Tg of the resin, the adhesion between the transferred thin film and the substrate sheet is low, and when it exceeds Tg + 70 ° C., the substrate It is not preferable because it is liable to cause deformation, warping or poor appearance.
In addition, Tg here is a value measured by a JIS-K7121 thermal flow rate differential scanning calorimetry test, and is a temperature at which a resin moves from a glassy solid to a rubbery elastic body by heating. .
As the surface material of the thermocompression-bonding roll, when using a resin material such as a heat-resistant resin material, various metals, ceramics, etc., the surface of the metal roll as the core material is lined with the heat-resistant resin material, To do. Examples of the heat-resistant resin material include silicone, neoprene, urethane, Teflon (registered trademark), etc. Silicone having high heat resistance, good workability, and various hardnesses are industrially available. preferable.

Moreover, when a transfer film contacts a thermocompression-bonding roll, the film is thermally expanded and wrinkles are easily generated. For this reason, as a material of the thermocompression-bonding roll surface, silicone rubber having moderate elasticity compared to metal or ceramic is preferable because it has an effect of suppressing wrinkles due to thermal expansion of the film.
Examples of the metal material include carbon steel, stainless steel, aluminum, and the like, and iron-based metals such as carbon steel that are relatively inexpensive and have high hardness and surface smoothness are preferable. Further, in order to further improve the hardness and surface smoothness and to improve the wear resistance and corrosion resistance, it is more preferable that the surface is subjected to chromium plating.

When a ceramic material is used, a thermocompression-bonding roll is formed by spraying ceramic on the surface of a metal roll serving as a core material to a thickness of about 100 to 300 microns. Examples of the ceramic material include alumina, titania, tungsten carbide, and the like, but alumina that is relatively inexpensive and has high thermal conductivity is preferable.
On the other hand, in a roll subjected to silicone rubber lining, the maximum set temperature is generally determined by the heat resistance temperature of the adhesive that bonds the lining and the metal that is the core material, and the set temperature is preferably 180 ° C. or less. Furthermore, when the extrusion process stops due to the end of production or due to trouble, etc., it is necessary to release the pressing pressure of the thermocompression bonding roll and remove the load of the thermocompression bonding roll from the extruded sheet. Heat accumulates on the surface of the thermocompression bonding roll, and the surface temperature of the thermocompression bonding roll may rise above the set temperature. In this case, if the temperature of the roll surface is equal to or higher than the heat resistance temperature of the adhesive that bonds the lining and the core material, damage such as lining dropping off from the core material may occur. Accordingly, the set temperature is more preferably 160 ° C. or lower in order to prevent roll breakage and perform stable production with a thermocompression-bonding roll having a silicone rubber lining.

However, silicone rubber has a thermal conductivity of about 0.2 W / m · K, which is significantly lower than that of metal or ceramic. Therefore, when a film with a high transfer temperature is used, the roll temperature is 160 ° C. or lower. May not be obtained.
In this case, it is preferable to further dispose the thermocompression-bonding roll on the downstream side of the rubber roll because it is possible to improve the adhesion by heating again. In particular, when a roll made of a material having a high thermal conductivity of 30 to 200 W / m · K, such as metal or ceramic, is disposed on the downstream side of the rubber roll and the thermocompression-bonding roll has a two-stage configuration, It is possible to perform primary heating at a set temperature of 160 ° C. or less while suppressing the occurrence of heat, and then to perform secondary heating with a higher temperature downstream roll, and even with a film having a high Tg of the adhesive layer and a high transfer temperature. Since favorable adhesiveness can be obtained, it is more preferable.

Further, when a transfer film having an adhesive layer Tg of about 60 to 80 ° C. is used, the thermocompression-bonding roll has a two-stage configuration, the upstream side is a silicone rubber roll, and the downstream side is a ceramic or metal roll. It is more preferable from the viewpoint of preventing the roll breakage because the set temperature of the silicone rubber roll can be set to a temperature lower than that when the thermocompression-bonding roll is a single-stage silicone rubber roll.
Moreover, you may arrange | position a multistage heating roll further downstream of the said metal or ceramic roll as needed.
In addition, by installing an expander roll, a spiral roll, etc. between the film supply roll and the thermocompression-bonding roll, the effect of reducing film wrinkles at the time of transfer is obtained, which is convenient.

The thickness of the thermoplastic resin sheet is appropriately determined depending on the use, but a thickness in the range of 0.5 to 5 mm is usually used.
When manufacturing the extruded sheet, the base film is continuously supplied so that the surface formed in this order of the thin film layer and the adhesive layer is on the extruded film surface side.
The extruded composite sheet of the thermoplastic resin obtained by transferring the thin film layer of the cured resin thus obtained and peeling off the base film has good appearance, good adhesion of the transferred thin film, and excellent scratch resistance. .
The base film may be peeled during the extrusion process or before the extruded composite sheet is actually used.

  In addition, as a method of transferring a thin film layer formed on the surface of the transfer film to the surface of the thermoplastic resin sheet to form a composite sheet, when the thermoplastic resin is formed into an extruded sheet, it is continuously rolled in the process. We have already mentioned that the method of supplying a roll transfer film and transferring it while applying heat and pressure with a roll is industrially more useful, but if transfer within the extrusion process is difficult, the conventional extrusion process It is also possible to obtain a composite sheet by heating and pressurizing the resin sheet obtained by the above by a thermocompression roll continuously supplied with a transfer film.

  The base film having releasability of the present invention has a releasability with respect to a thin film layer made of a cured resin formed on the surface thereof, and has a strength having a self-holding property free from problems such as sagging and cracking. Point to. For example, it refers to polyethylene terephthalate (hereinafter referred to as “PET”), polyethylene (hereinafter referred to as “PE”), polypropylene (hereinafter referred to as “PP”), PC, cellulose acetate or the like, or a composite film of these materials. Also includes mold-treated ones. The thickness of the base film is usually in the range of 5 to 150 μm, preferably in the range of 10 to 100 μm. It is preferable because a good composite sheet can be obtained.

  The thin film layer comprising the cured resin of the present invention is an acrylate-based cured resin selected from diacrylate, triacrylate, dimethacrylate, urethane acrylate, polyester acrylate, epoxy acrylate, alkyd acrylate, silicon acrylate, polyester urethane acrylate, or alkoxysilane. , Preferably a silicone-based cured resin selected from organopolysiloxane, etc., dissolved in a solvent together with a curing agent, and applied to one side of the base film by a normal method such as gravure coating method, roll coating method, reverse roll method, A method of forming by drying and curing by heating or irradiation with ultraviolet rays is recommended.

The thin film layer thus formed preferably has a surface hardness (value measured by a JIS-K5400 hand-drawing method) of 3H or more. Thickness is 1 micrometer or more from a viewpoint of performance expression, and is suitably selected from the range of 10 micrometers or less from the problem of the coating-film crack after hardening.
An intermediate thin film of a known epoxy compound may be formed in the range of 1 to 10 μm in order to improve adhesion and flexibility between the base resin thin film and the adhesive layer.
As the adhesive layer used in the present invention, a general acrylic, vinyl acetate, vinyl chloride, styrene-butadiene, polyester, ethylene-vinyl acetate, urethane or the like is used alone or a mixture thereof. The emulsion resin or organic solvent type resin is appropriately selected and used.

The Tg of the adhesive layer is generally 100 ° C. or lower, which is a lower value than the Tg of the resin sheet. However, in this method, since the heating time is a moment when the roll passes, the Tg of the adhesive layer has a great influence on the adhesion. For this reason, Tg of the adhesive layer of a transfer film is so good that it is low, Preferably it is 60-80 degreeC.
The adhesive layer is formed by applying and drying a coating liquid obtained by diluting the resin with water or an organic solvent on a thin film by gravure printing, screen printing, or offset printing. The thickness of the adhesive layer is appropriately selected from the range of usually 0.3 to 20 μm according to the surface state of the transfer sheet.
The thermoplastic resin used in the present invention is selected from thermoplastic resins capable of extrusion sheet molding. Examples include acrylic, styrene, acrylic-styrene copolymer (hereinafter referred to as MS), vinyl chloride, acrylonitrile. -Butadiene-styrene copolymer, PET, PC resin alone, and a mixture thereof are relatively advantageous in that the adhesion to the thin film layer is relatively large when the thin film layer is transferred from the base film. Vinylidene fluoride or the like is not recommended because of its relatively low adhesion to the thin film layer when the thin film layer is transferred from the base film.

These resins may contain other components such as a color pigment, a coloring dye, a heat stabilizer, an antioxidant, a light stabilizer, and an ultraviolet absorber as long as the properties are not impaired.
Among them, acrylic resins, MS resins, which have high transparency and sufficient mechanical strength and durability required for video equipment front plates, frame face plates, partition plates, etc., and which can provide extruded sheets with high surface accuracy, The PC resin is recommended as a suitable thermoplastic resin for adding various functions such as surface protection, surface reflection prevention, and antistatic.
Here, the high transparency means that the total light transmittance measured by JIS-K7105 is 80% or more, more preferably 85% or more when the thickness is 2 mm. For example, acrylic resin, MS resin, PC Resin.

Examples of the acrylic resin include resins mainly composed of methyl methacrylate, which include a homopolymer of methyl methacrylate or methyl methacrylate and methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, butyl acrylate, acrylonitrile, Copolymers with any one or more of copolymerizable monomers such as acrylic acid, methacrylic acid, 2-hydroxyacrylate, maleic anhydride, or α-methylstyrene are included. These may be used alone or may be blended.
In order to improve the impact strength of acrylic resin, multi-stage sequential generation of alternating elastic layer mainly composed of butyl acrylate and non-elastic layer mainly composed of methyl methacrylate around acrylic polymer core material What blended the rubber elastic body manufactured by the polymerization method with acrylic resin is also contained in the acrylic resin of this invention.

The MS resin is an acrylic-styrene copolymer, more specifically a copolymer of methyl methacrylate and styrene, and the copolymerizable monomer exemplified in the above acrylic resin with methyl methacrylate and styrene as main components. Are also included, and these may be used alone or in a blend.
In order to improve the impact strength of MS resin, multi-stage sequential generation of alternating elastic layer mainly composed of butyl acrylate and inelastic layer mainly composed of methyl methacrylate around acrylic polymer core material A rubber elastic body produced by a polymerization method or a butadiene rubber elastic body blended with an MS resin is also included in the MS resin of the present invention.
Examples of the PC resin include aromatic polycarbonates typified by the bisphenol A type, and aromatic-aliphatic polycarbonates having an aromatic ring but having no hydroxyl group directly bonded to the aromatic ring.

Hereinafter, the present invention will be described based on examples.
The evaluation and test methods used in each example and comparative example are as follows.
(1) Measurement of sheet surface temperature: A K-type thermocouple is attached to the resin sheet surface, and the resin sheet surface temperature when passing through the thermocompression-bonding roll is measured.
(2) Appearance determination: Visually determine whether there is any abnormality that impairs the smoothness of the surface and other appearances. The state is recorded as ◯ when it is good, △ when there is some defect but no problem in practical use, and x when there is an abnormality that cannot be put into practical use.

(3) Judgment of adhesion: Performed in accordance with JIS-K5400 cross cut tape test method. That is, a 100 mm grid with a 1 mm ² square is attached to the bonded film surface using a cutter, and after attaching cello tape to this, it is strongly peeled off by hand, and the presence or absence of peeling of the bonded film is determined. A case where peeling does not occur in all 100 mm is indicated as ◯, and a slight peeling occurs in the vicinity of the notch portion of the cutter, but a case where the peeling area per 1 mm is 50% or less for all 100 mm is indicated as Δ. To do. Furthermore, when even one wrinkle having a peel area per wrinkle of 50% or more occurs, it is marked as x.
(4) Total light transmittance: Measured according to JIS-K7105.
(5) Surface hardness: Measured according to JIS-K5400 handwriting method.

[Example 1]
As the thermoplastic resin, an acrylic resin (Delpet 70H, transparent / Asahi Kasei Co., Ltd. product) having a Tg of about 104 ° C. is used, an extruder (screw diameter: 50 mm, L / D: 32, single axis), sheet die, Then, an extruded sheet is formed by a conventional method using a unit composed of three polishing rolls for cooling and glazing and a take-up roll to produce an extruded sheet having a width of 300 mm.
The resin temperature during the extrusion of the used resin was adjusted to 260 ° C., and the sheet extrusion speed was adjusted to 3 m / min. Moreover, the thickness of the sheet was adjusted to 1.0 mm by adjusting the discharge amount of the extruder and the interval between the sheet die discharge port and the polishing roll.
The resulting thermoplastic resin sheet had a surface hardness of 2H and a surface resistance value of more than 10 ¹⁶ Ω.

  On the other hand, a solution comprising 20 parts of diethylene glycol dimethacrylate, 10 parts of epoxy acrylate, 1 part of benzoin isopropyl ether, 40 parts of toluene, 20 parts of methyl ethyl ketone (hereinafter referred to as MEK) and 10 parts of isopropyl alcohol on one side of a PET film having a thickness of 38 μm. Is applied by a reverse roll method and dried, and then cured by irradiation with a UV lamp to form a cured resin film having a thickness of 3.5 μm.

On this cured resin film, 75 parts of alicyclic epoxy compound Celoxide 2021 (manufactured by Daicel Corporation), 3 parts of 1,4-cyclhexanehexane methylol divinyl ether, 15 parts of phenol novolac epoxy resin (manufactured by Asahi Ciba Co., Ltd.), Apply a paint consisting of 4 parts of a cationic photopolymerization initiator (Union Carbide Co., Ltd.) and cure it by irradiating with a mercury lamp to form an intermediate film having a thickness of 1.5 μm. A transfer film is obtained by applying an acrylic paint (resin content 20 parts, toluene 50 parts, MEK 30 parts) at about 60 ° C. and drying to form an adhesive layer having a thickness of 1 μm.
In addition, this transfer film is prepared in a roll winding form by a processing device that supplies a base film from an unwinding roll to a winding roll through processing units such as an application unit and a drying unit.

In the middle of the polishing roll and the take-up roll and the sheet surface temperature is below Tg of the resin, a thermocompression-bonding roll is disposed at a position of about 80 ° C., and the adhesive layer is positioned on the sheet surface side, The transfer film in the form of a roll is continuously supplied via a film supply roll and a thermocompression-bonding roll, and is attached to both sides of the sheet. For the purpose of removing dust, a static elimination air supply device (SJ-R036 manufactured by Keyence Corporation) is installed in front of the thermocompression-bonding roll.
The thermocompression-bonding roll here has a 3 mm thickness lining of a silicone rubber having a Shore hardness of Hs60 on the surface of the metal roll.

The film supply at the sticking stage is under a tension stress of 0.03 kg / cm (per unit length in the width direction of the film supply roll), the temperature of the thermocompression bonding roll is 160 ° C., and the pressure of the thermocompression bonding roll is 6 kg. It was carried out while applying a linear pressure of / cm (per unit length in the width direction of the roll).
The resin sheet surface temperature when passing through the thermocompression-bonding roll was 125 ° C.
The sticking sheet is cut to a length of 60 cm and the base film is peeled off. The obtained extruded composite sheet has a high total light transmittance and is substantially free from defects such as surface irregularities that impair the appearance. It has a good appearance equivalent to an acrylic resin sheet.
In addition, the surface hardness is significantly higher than before the composite sheet, resulting in an extruded composite sheet having excellent scratch resistance and excellent surface protection performance.

[Example 2]
Except for using an acrylic resin having a Tg of about 90 ° C. as the adhesive layer, a transfer film similar to that used in Example 1 was used, and the surface of the metal roll was lined with a silicone rubber having a Shore hardness of Hs60 with a thickness of 3 mm. On the downstream side of the pressure roll, a thermocompression roll in which ceramic is sprayed to a thickness of 0.2 mm on the surface of the metal roll is installed to form a thermocompression roll in a two-stage configuration. The set temperature of the silicone rubber roll is 160 ° C. A composite sheet is obtained in the same manner as in Example 1 except that the set temperature is 200 ° C.
The sheet surface temperature when passing through the thermocompression-bonding roll is 145 ° C., and the obtained composite sheet has a high total light transmittance and is substantially free from defects that impair the appearance such as surface irregularities, and is obtained by an ordinary method. It has the same good appearance as
In addition, the surface hardness is significantly higher than before the composite sheet, resulting in an extruded composite sheet having excellent scratch resistance and excellent surface protection performance.

[Example 3]
A composite sheet is obtained in the same manner as in Example 2 except that the transfer film used in Example 1 is used and the set temperature of the silicone rubber roll is 140 ° C. and the set temperature of the ceramic roll is 180 ° C.
The sheet surface temperature when passing through the thermocompression-bonding roll is 131 ° C., and the obtained composite sheet has a high total light transmittance and is substantially free from defects that impair the appearance such as surface irregularities, and is obtained by an ordinary method. It has the same good appearance as
In addition, the surface hardness is significantly higher than before the composite sheet, resulting in an extruded composite sheet having excellent scratch resistance and excellent surface protection performance.

[Example 4]
A cured resin film is formed on one side of a 50 μm-thick PET film in the same manner as in Example 1, and an antistatic thin film having a thickness of 2 μm and an adhesive layer are formed thereon as follows. .
After 30 parts of tin oxide fine powder was dispersed by a ball mill with 100 parts of acrylic transparent paint having a solid content of 18% by ball milling, a solution diluted with MEK was applied and dried to form an antistatic thin film. An acrylic adhesive layer at 60 ° C. is sequentially formed.
The antistatic thin film had a surface resistance value of 10 ⁷ Ω.
After sticking this transfer film at the time of extrusion of the acrylic resin sheet in the same manner as in Example 1, the extruded composite sheet obtained by peeling off the base film is substantially free from defects that impair the appearance such as surface irregularities, by a conventional method. It has a good appearance equivalent to the acrylic resin sheet obtained.
The obtained extruded composite sheet has a surface resistance value of 10 ⁹ Ω, which is much lower than that of the original acrylic resin, and has sufficient antistatic performance.

[Example 5]
By adjusting the discharge rate of the extruder, the sheet die discharge port and the polishing roll, the thickness of the sheet is adjusted to 3.0 mm, the set temperature of the silicone rubber roll is 160 ° C., and the set temperature of the ceramic roll is 220 ° C. As in Example 3, a composite sheet is obtained.
The obtained extruded composite sheet has a good appearance equivalent to that of an acrylic resin sheet obtained by a conventional method, having a high total light transmittance and substantially free from defects such as surface irregularities.
In addition, the surface hardness is significantly higher than before the composite sheet, resulting in an extruded composite sheet having excellent scratch resistance and excellent surface protection performance.

[Example 6]
A composite sheet is obtained in the same manner as in Example 3 except that the setting temperature of the silicone rubber roll is 180 ° C. and the setting temperature of the ceramic roll is 220 ° C.
The sheet surface temperature at the time of passing through the thermocompression-bonding roll was 163 ° C., and the obtained composite sheet had no problem in practical use although slight undulation occurred. Moreover, it is an extruded composite sheet that has a high total light transmittance, a surface hardness that is significantly improved as compared with that before the composite sheet, and excellent surface protection performance with excellent scratch resistance.

[Example 7]
A composite sheet is obtained in the same manner as in Example 1 except that the transfer film used in Example 2 is used, the thermocompression-bonding roll has a one-stage configuration of silicone rubber lining, and the set temperature of the roll is 180 ° C.
The sheet surface temperature at the time of passing through the thermocompression-bonding roll was 135 ° C., and the obtained composite sheet showed adhesion with no problem in practical use, although some peeling occurred in the vicinity of the notch in the cutter. . Moreover, it has a high total light transmittance and a good appearance equivalent to that of an acrylic resin sheet obtained by a conventional method, which is substantially free from defects such as surface irregularities that impair the appearance.
Furthermore, the surface hardness is significantly higher than before the composite sheet, and the extruded composite sheet has excellent scratch resistance and excellent surface protection performance.

[Example 8]
A composite sheet is obtained in the same manner as in Example 1 except that the thermocompression-bonding roll has a one-stage structure of ceramic spraying and the set temperature of the roll is 160 ° C.
The sheet surface temperature at the time of passing through the thermocompression-bonding roll is 133 ° C., and the obtained composite sheet has some defects on the film end face, but there is substantially no defect that impairs the appearance of the part used as a product. There was no problem in practical use. Moreover, the total light transmittance is high, the surface hardness is significantly higher than before the composite sheet, and the extruded composite sheet has excellent scratch resistance and excellent surface protection performance.

[Comparative Example 1]
A composite sheet is obtained in the same manner as in Example 1 except that the thermocompression-bonding roll has a one-stage configuration of silicone rubber lining and the set temperature of the roll is 120 ° C.
The sheet surface temperature when passing through the thermocompression-bonding roll was 98 ° C., and the obtained composite sheet had poor adhesion.

[Comparative Example 2]
A composite sheet is obtained in the same manner as in Example 2 except that the thermocompression-bonding roll has a two-stage structure of silicone rubber lining and ceramic spraying, the setting temperature of the silicone rubber roll is 180 ° C., and the setting temperature of the ceramic roll is 240 ° C.
The sheet surface temperature at the time of passing through the thermocompression-bonding roll was 180 ° C., and the obtained composite sheet had remarkable undulations and had a poor appearance.

[Comparative Example 3]
The composite sheet is the same as in Example 1 except that a thermocompression-bonding roll is disposed at a position between about the polishing roll and the take-up roll and the thermoplastic resin extruded sheet surface temperature is about 120 ° C., which is equal to or higher than Tg + 10 of the resin. Get.
The sheet surface temperature when passing through the thermocompression-bonding roll was 142 ° C., and the resulting composite sheet had significant undulations.

The method for producing a composite extruded sheet according to the present invention can be applied to all fields of use that require surface modification of a resin sheet.
In other words, it can be applied to the fields of electrical / electronic products, vehicle interior / exterior parts, interior / exterior building materials, displays, etc., and is particularly suitable in the field of use of transparent resins represented by the front plates, picture frames, and partition plates of video equipment. Available to:

It is a conceptual diagram of the extrusion sheet manufacturing machine which shows an example of implementation of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sheet die 2 Polishing roll 3 Thermoplastic resin sheet 4 Transfer film 5 Resin lining thermocompression-bonding roll 6 Metal thermocompression-bonding roll 7 Take-off roll 8 Composite resin sheet 9 Film original fabric 10 Film supply roll

Claims (4)

  A method for producing an extruded composite sheet made of a thermoplastic resin, wherein the surface temperature of a thermoplastic resin sheet formed by an extruder sheet die is cooled to Tg + 10 ° C. or lower, and then a cured resin is formed on a base film surface having releasability When the transfer film formed in the order of the thin film layer A and the adhesive layer B is supplied and the one or both sides of the resin sheet are bonded to the B layer, the surface of the resin sheet is heated in the range of Tg + 10 ° C. to Tg + 70 ° C. A method for producing an extruded composite sheet, characterized by crimping and then removing the base film.   2. The method for producing an extruded composite sheet according to claim 1, wherein after thermocompression bonding with a thermocompression-bonding roll having a heat-resistant resin lining on its surface, the thermocompression-bonding is again performed with a metal thermocompression-bonding roll.   2. The extruded composite sheet according to claim 1, wherein after heat-pressing with a thermo-compression roll having a heat-resistant resin lining on the surface, heat-pressing is again performed with a thermo-compression roll having thermal sprayed ceramic on the surface. Method.   The surface is lined with a heat-resistant resin and heat-pressed by a thermocompression-bonding roll heated to a predetermined temperature of 160 ° C. or lower, and then the outer surface is brought to a predetermined temperature within a range of 160 ° C. to 250 ° C. The method for producing an extruded composite sheet according to any one of claims 1 to 4, wherein the heat-compression bonding is performed again with a heated thermocompression-bonding roll.

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