JP3727261B2 - Manufacturing method of uneven sheet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an uneven sheet that can be used as a member for forming unevenness on a decorative sheet or the like.
[0002]
[Prior art]
Conventionally, a concavo-convex sheet has been used to obtain a decorative sheet or the like having a three-dimensional wood grain conduit, streaks, or the like. This concavo-convex sheet is a concavo-convex formed on a base sheet, and the following methods were used to form the concavo-convex on the base sheet.
[0003]
(1) As a method by heating and pressing, a hot press mold or a hot press roll is pressed against the surface of a base sheet made of a smooth thermoplastic resin sheet to soften the surface of the base sheet and at the same time a hot press mold or heat There is a method of copying an uneven (embossed) pattern on the surface of a press roll.
[0004]
(2) As a printing method using a gravure plate, a liquid photocurable resin is provided on a base sheet by gravure printing, then irradiated with light to cure the photocurable resin, and the gravure plate unevenness (emboss) There is a method of forming a pattern on the surface of a base sheet.
[0005]
[Problems to be solved by the invention]
In the method (1), the production of the hot press mold and the hot press roll requires a number of processes, and a high production cost is required. In addition, it is not easy to change the uneven pattern of a hot press die or hot press roll, and a new hot press die or hot press roll must be prepared each time a change is requested, which is uneconomical. It was. Since the thermoplastic resin sheet is softened and pressed with a hot press mold or hot press roll to copy the concavo-convex pattern, if the pressing of the hot press mold or hot press roll is released at the fine convex portions or concave portions, it tends to return flat. It was.
[0006]
In the method (2), the height of the convex portion can be only about 40 μm at most in the unevenness of the gravure plate, and the degree of the unevenness is limited. In addition, since the light curable resin is a liquid having a low degree of viscosity, after gravure printing, ink sagging occurred on the surface of the base sheet, and the uneven pattern was destroyed. Thus, the intended uneven pattern was not obtained.
[0007]
[Means for Solving the Problems]
The method for producing a concavo-convex sheet according to the present invention is such that a light curable resin droplet is dropped or released on a substrate sheet, and after the light curable resin droplet adheres to the substrate sheet, the light beam is irradiated separately for each droplet. An unevenness is formed on the base sheet by curing the conductive resin droplets.
[0008]
In the method for producing a concavo-convex sheet according to the present invention, light curable resin droplets are dropped or ejected on a base sheet, and the light is separately irradiated for each drop before the light curable resin droplets adhere to the base sheet. After the curable resin droplets are semi-cured, and then the light curable resin droplets adhere to the base sheet, the light curable resin droplets are re-irradiated to cure the light curable resin droplets, thereby forming irregularities.
[0009]
In the method for producing a concavo-convex sheet according to the present invention, light curable resin droplets are dropped or ejected on a base sheet, and the light is separately irradiated for each drop before the light curable resin droplets adhere to the base sheet. The curable resin droplets are semi-cured to maintain the irradiation state, and after the light curable resin droplets adhere on the substrate sheet, the light curable resin droplets are cured to form irregularities.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to the drawings.
[0011]
In the production method of the present invention, light curable resin droplets are dropped or released on a base sheet, and after the light curable resin droplets are attached to the base sheet, the light rays are separately irradiated to each of the droplets to form a light curable resin droplet. Is a method for producing a concavo-convex sheet, wherein the concavo-convex sheet is formed on the substrate sheet by curing.
[0012]
First, the base sheet 1, the light curable resin droplet 2 and the uneven sheet manufacturing apparatus used in the method for manufacturing the uneven sheet according to the present invention will be described.
[0013]
Examples of the material of the base sheet 1 include polyester resins, polypropylene resins, polyurethane resins, acrylic resins, fluorine resins, vinyl resins, and polyethylene resins. The thickness of the base sheet 1 is preferably 0.01 to 3 mm. If it is thinner than 0.01 mm, wrinkles are likely to occur, and if it is thicker than 3 mm, it becomes bulky and difficult to handle as a sheet.
[0014]
As the light curable resin, a liquid of a resin (oligomer or prepolymer) that is cured by irradiating light rays such as ultraviolet rays, electron beams, and laser beams is used. Examples of the light curable resin include an ultraviolet curable resin, an electron beam curable resin, an α ray curable resin, a β ray curable resin, a γ ray curable resin, and a laser light curable resin. Specific examples of the photocurable resin include ester acrylate resins, urethane acrylate resins, epoxy acrylate resins, amino acrylate resins, unsaturated polyester resins, and the like. There are polymerization type, 3) thiol / ene addition type.
[0015]
Moreover, a diluent can be used when using high viscosity photocurable resin. As this diluent, an organic solvent or a reactive diluent (photopolymerizable monomer) can be used. Examples of reactive diluents include monofunctional groups such as 2-ethylhexyl acrylate, ethoxydiethylene glycol acrylate, phenoxyethyl acrylate, 2hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, dicyclopentenyl acrylate, vinylcyclohexene monooxide, hydroxybutyl vinyl ether, etc. Difunctional, such as neopentyl glycol diacrylate, 1.6 hexanediol diarylate, hydroxypivalate neopentyl glycol diacrylate, polyethylene glycol diacrylate, bis (acryloxyethyl) bisphenol A, melimetyrolpropane Triacrylate, pentaerythritol triacrylate, dipentaerythritol hexylacrylate Include the polyfunctional etc., it can be used as these alone or composite. In addition, a photopolymerization initiator, a sensitizer, a filler, a paint additive (leveling agent, antifoaming agent), a non-reactive resin, a colorant, and the like can be added as necessary. Examples of the filler include inorganic substances such as silica and calcium carbonate, and organic substances such as acrylic beads and urethane beads. By adding these fillers, the surface of the photocurable resin droplets to be dropped or emitted can be made into a mat or the like. Examples of the colorant include dyes, pigments, and aluminum pastes. These fillers are of such a size that the dripping or releasing light curable resin droplets are not destroyed.
[0016]
The concavo-convex sheet manufacturing apparatus includes a light curable resin dropping / releasing device that can drop or release a light curable resin droplet 2 on the base sheet 1, and a light beam that is dropped or emitted on the base sheet 1. And a light beam irradiation device capable of curing the curable resin droplet 2.
[0017]
The photocurable resin dropping / releasing device is a device for dropping or releasing the photocurable resin droplet 2. The light curable resin dropping / releasing device basically includes a mechanism for dropping or releasing light curable resin droplets from the tip of the nozzle 4 (capillary tube) in accordance with an electrical signal. Examples include a dispenser 3, an ink jet printer, a bubble jet printer, and the like. As a general dispenser 3, there is a type in which a liquid photocurable resin in a syringe is pressed by hydraulic pressure or air pressure and pushed out from the tip of a nozzle 4 (see FIG. 1). By adjusting the size of the opening of the nozzle 4, the hydraulic pressure and the air pressure, the size of the light curable resin droplet 2 that is dropped or emitted can be adjusted. A general ink jet printer is a type of printer that prints by ejecting ink onto paper with heat or pressure. There are a method for ejecting ink by utilizing expansion due to heat, a method for utilizing foaming of ink by heat, a method for flying ink by utilizing an electrostrictive effect, and the like. As a general type of bubble jet printer, the heater on the nozzle causes film boiling of ink on the heater surface, generating bubbles, and the discharged ink is used for recording as ink droplets. A printer that can be used.
[0018]
As the light irradiation device, there are an ultraviolet irradiation device 5, an electron beam irradiation device, an α ray irradiation device, a β ray irradiation device, a γ ray irradiation device, and a laser beam irradiation device. Examples of the ultraviolet irradiation device and the electron beam irradiation device include a high pressure mercury lamp, a metal halide lamp, a xenon lamp, and a low pressure mercury lamp. In the case of irradiating the pinpoint with ultraviolet rays, the ultraviolet rays radiated from the diameter of the glass fiber 6 can be applied to the glass fiber 6 to irradiate the photocurable resin droplets 2 dropped or emitted (FIG. 1). reference). Examples of the laser beam irradiation device include a carbon dioxide laser device, a YAG laser device, a ruby laser device, and a VYO ↓ 4 laser device.
[0019]
Below, the manufacturing method of an uneven | corrugated sheet is demonstrated.
[0020]
First, the light curable resin droplet 2 is dropped or discharged from the base sheet 1.
[0021]
As the base sheet 1, the above-described one can be used. In order to drip or release the light curable resin droplet 2, the above-described light curable resin dropping / releasing device can be used.
[0022]
When the dispenser 3 is used as a light curable resin dropping / releasing device, the light curable resin droplet 2 is dropped or released with the light curable resin facing the front surface of the base sheet 1 and an arbitrary uneven pattern. It can be done by moving it like drawing. The movement of the dispenser 3 can be performed by a three-axis control robot. The base sheet 1 can be moved on an XY table.
[0023]
Next, the light curable resin droplets are dropped or released on the base sheet, and after the light curable resin droplets adhere to the base sheet, the light curable resin droplets are individually irradiated to cure the light curable resin droplets. Thus, irregularities are formed on the base sheet.
[0024]
As the types of unevenness to be formed on the base sheet 1, the unevenness corresponding to the matte pattern, the unevenness corresponding to the mat, the conduit and the line of the grain, the unevenness corresponding to the woven fabric pattern, the unevenness corresponding to the leather pattern, There are irregularities corresponding to the hairline pattern. The height of the convex and concave portions formed by the light-curing resin droplets 2 dropped or emitted is 1 to 60 μm.
[0025]
In this invention, the number of the photocurable resin droplets 2 dropped or emitted stacked on the base sheet is changed, or the size of the photocurable resin droplets 2 dropped or emitted is changed. The width can be increased (see FIG. 2).
[0026]
In order to change the number of dripped or released light curable resin droplets 2 stacked on the base sheet, three-tiered pyramid-shaped protrusions (FIG. 2 (a)) or four-tiered pyramid There are a convex portion (FIG. 2B) formed into a shape, and a convex portion (FIG. 2C) composed of a three-tiered portion and a one-tiered portion. In these cases, the height of the uneven projection can be finely adjusted.
[0027]
As a case where the size of the photocurable resin droplet 2 to be dropped or emitted is changed, a convex portion in which droplets larger than those described in FIGS. 2 (d)), and convex portions (FIG. 2 (e)) formed by combining the light curable resin droplets 2 having different sizes. In these cases, since the number of times of dropping or discharging is small, it is economical.
[0028]
As described above, when the light-curing resin droplets 2 dropped or emitted are stacked to form unevenness, unevenness having a so-called undercut can also be formed (see FIG. 3). In this case, it is possible to enhance the design effect such that the division between the concave portion and the convex portion becomes clear.
[0029]
Moreover, in this invention, an unevenness | corrugation may be formed by integrating several light-curing resin droplets 2 before hardening or at the time of hardening (refer FIG. 4). Only two or three large light-curing resin droplets 2 may be integrated (see FIG. 4A), or a large number of small light-curing resin droplets 2 are stacked and integrated to form irregularities. It may be allowed (see FIG. 4B). The reason for integrating before curing or at the time of curing is that the plurality of light-curing resin droplets 2 are still in a liquid state, so that they are easily integrated.
[0030]
In the present invention, the photocurable resin droplets 2 dropped or emitted by the irradiation of the light beam are individually cured for each droplet (see FIG. 1). In this case, generally, the photocurable resin droplet 2 is dropped from the photocurable resin dropping / releasing device. Since the dropped light curable resin droplet 2 retains the outer shape of the droplet almost as it is and cures in units of one droplet, it is possible to form a fine unevenness with sharp edges.
[0031]
In this invention, light curable resin droplets are dropped or released on the substrate sheet, and before the light curable resin droplets adhere to the substrate sheet, the light beams are irradiated separately for each droplet, and the light curable resin droplets are half-divided. After the curing and then the light curable resin droplets adhere on the substrate sheet, the light curable resin droplets may be re-irradiated to cure the light curable resin droplets, thereby forming irregularities.
[0032]
In addition, the photocurable resin droplets are dropped or released on the substrate sheet, and before the photocurable resin droplets adhere to the substrate sheet, the light beams are irradiated separately for each droplet to semi-cure the photocurable resin droplets. The irradiation state may be maintained, and then the light curable resin droplets may adhere to the base sheet, and then the light curable resin droplets may be cured to form irregularities.
[0033]
In these cases, by semi-curing before adhering to the base sheet 1, the shape of the droplets is not deformed or destroyed by impact when the light curable resin 2 collides with the base sheet 1. It can be effective. Moreover, the semi-cured state is preferable in that it is easy to firmly adhere to the base sheet 1 and the adjacent light-curable resin droplets 2 are more easily bonded. In addition, adjustment of the timing which irradiates a light can utilize the electrical signal when the light curable resin droplet 2 is dripped or discharge | released.
[0034]
The degree to which the light curable resin droplet 2 is cured may be basically cured to the extent that no stickiness remains on the surface of the light curable resin droplet 2 (also referred to as “touch drying”). For example, the photocurable resin droplet 2 can be cured so as to have a numerical value of 30 to 60 by the measurement method of JISA hardness. When a colored layer of characters, figures, patterns, etc. is formed by printing on the surface of the substrate sheet 1 on the side to which the light curable resin droplets 2 adhere, the hardness of the light curable resin droplets 2 is determined by the solvent of the printing layer. It should be not attacked.
[0035]
The unevenness is formed by the cured photocurable resin droplets 7 attached on the base sheet 1. The unevenness may be formed on the entire surface of the substrate sheet 1 or may be formed in a linear shape only in a necessary portion. In the case where the film is formed only in a necessary portion, the surface of the base sheet 1 is exposed except the portion where the hardened droplets 7 are present (see FIG. 2).
[0036]
The uneven sheet obtained as described above can be used, for example, as follows. Hereinafter, the case where it uses as a member for forming an unevenness | corrugation in the decorative sheet which has the design of the metallic tone to which the mat was given is described.
[0037]
As an example, a colored layer 8 is formed by screen printing with an ink partially containing an aluminum paste on the side where the unevenness formed by the cured photocurable resin droplet 7 of the uneven sheet is formed, and further an adhesive layer 9 can be formed by screen printing to obtain a decorative sheet (FIG. 5A). In this case, a release layer can be formed by printing between the concavo-convex sheet and the colored layer to form a so-called transfer sheet. A transfer sheet is a sheet that is used to copy the unevenness of the concavo-convex sheet onto the surface of the transferred object by peeling the uneven sheet after the adhesive layer of the transfer sheet is adhered to the surface of the transferred object. Say.
[0038]
As another example, a colored layer is formed by screen printing with an ink partially containing an aluminum paste on the base sheet 1 side where the unevenness of the uneven sheet is not formed, and further an adhesive layer is formed by screen printing, A decorative sheet can be obtained. In this case, the hardened droplet 7 is exposed on the outermost surface of the decorative sheet (see FIG. 5B).
[0039]
For example, there is a method in which the uneven sheet is deformed into a three-dimensional shape as necessary and then put into an injection mold, and the uneven sheet is fused to the molded product by the heat and pressure of the molding resin simultaneously with the injection molding. Examples of the material of the molded product include acrylic resin, polypropylene resin, ABS resin, polystyrene resin, polycarbonate resin, and noryl resin.
[0040]
【Example】
A photo-curing resin dripping / releasing device in which a dispenser equipped with a nozzle that drops 0.01 ml as a drop is attached to a three-axis control robot capable of controlling in the XYZ-axis direction, and the tip of this nozzle A light beam irradiating apparatus was prepared that can cure the light curable resin droplets in units of one drop by sending ultraviolet light from the glass fiber toward the surface and irradiating with ultraviolet light from the tip of the glass fiber. As the resin supplied from the dispenser, an ultraviolet curable resin containing urethane allylate resin and 2-ethylhexyl acrylate as a reactive diluent is used, and a 0.2 mm thick transparent base sheet made of polycarbonate is used on an XY table. A transparent UV curable resin was dropped from the nozzle of the dispenser. According to the data of the wood grain pattern, the convex part of the wood grain pattern conduit was formed by controlling the robot with the dispenser in the XY directions. The robot was controlled in the Z direction to control the amount of photocurable resin droplets that were dropped from the dispenser and stacked. Ultraviolet rays were irradiated in units of one drop of the ultraviolet curable resin dripped from the nozzle and adhered on the substrate sheet. In this way, an uneven sheet was obtained.
[0041]
【The invention's effect】
Since the present invention adopts the configuration as described above, the following effects can be obtained.
[0042]
That is, it is not necessary to prepare a hot press mold and a hot press roll, and the uneven pattern can be easily changed, which is economical. Even a fine convex part or concave part does not return flatly. The depth of the unevenness of the uneven pattern can be adjusted arbitrarily. The light curable resin does not cause ink sagging, and an uneven pattern having an intended shape can be obtained with certainty.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing one step of a method for producing an uneven sheet according to the present invention.
FIG. 2 is a cross-sectional view showing an example of an uneven sheet according to the present invention.
FIG. 3 is a cross-sectional view showing an example of an uneven sheet according to the present invention.
FIG. 4 is a cross-sectional view showing an example of an uneven sheet according to the present invention.
FIG. 5 is a cross-sectional view showing an example of an uneven sheet according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base sheet 2 Photocurable resin droplet 3 Dispenser 4 Nozzle 5 Ultraviolet irradiation apparatus 6 Glass fiber 7 Cured droplet 8 Colored layer 9 Adhesive layer

Claims (3)

  A base sheet is obtained by dropping or releasing light curable resin droplets on a base sheet, and after the light curable resin droplets adhere to the base sheet, the light is separately irradiated to cure the light curable resin drops. The manufacturing method of the uneven | corrugated sheet | seat characterized by forming an unevenness | corrugation on top.   A photocurable resin droplet is dropped or released on the substrate sheet, and before the photocurable resin droplet adheres to the substrate sheet, the photocurable resin droplet is semi-cured by irradiating light separately for each droplet, and then A method for producing a concavo-convex sheet, characterized in that, after the light curable resin droplets are deposited on the substrate sheet, the light curable resin droplets are re-irradiated to cure the light curable resin droplets, thereby forming irregularities.   Drop or release photocurable resin droplets on the substrate sheet, and irradiate the beam separately for each drop before the photocurable resin droplets adhere to the substrate sheet to semi-cure the photocurable resin droplets, and then irradiate A method for producing a concavo-convex sheet, comprising maintaining a state, and then forming a concavo-convex by curing a light curable resin droplet after the light curable resin droplet adheres to a base sheet.

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