JP4023294B2 - Method for manufacturing lenticular lens sheet - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a lenticular lens sheet used for a projection screen used as a screen of a projection television, a microfilm reader, etc., and more specifically, can provide an image with a good appearance, a high contrast, and a black The present invention relates to a method for manufacturing a lenticular lens sheet capable of forming stripes with high productivity.
[0002]
[Prior art]
On projection screens such as CRT projectors, LCD projectors, and DMD (digital micromirror device) projectors, projection televisions and microfilm readers form images that are projected and diffuse incident light. In order to increase the viewing angle, a lenticular lens sheet is used in combination with a Fresnel lens sheet or the like.
[0003]
This lenticular lens sheet is formed by connecting a large number of lenticular lenses having a substantially elliptical cross section on at least one of the entrance surface and the exit surface, and an LCD projector using a transmissive or reflective liquid crystal display element. When used in a DMD projector, a single-sided lenticular lens sheet in which a lenticular lens is formed only on the incident surface is used, and in a case of being used in a CRT projector, both surfaces in which a lenticular lens is formed on both the incident surface and the exit surface. A lenticular lens sheet is used.
[0004]
In this way, in the lenticular lens sheet, a large number of long and narrow lenticular lenses are arranged in series, so that a band-like dark portion (light non-light) through which light does not pass due to the refractive condensing action of the lenticular lens formed on the entrance surface. A transmission part) is formed. On the other hand, as a projection screen for a projection television or the like, an image with high contrast is required so that the image can be clearly observed even when the image is observed in a bright room. For this reason, in the projection screen, a light absorbing layer (black stripe) is formed using a light absorbing material such as black ink containing a black pigment or dye at the light-impermeable portion of the exit surface of the lenticular lens sheet. Therefore, reflection of external light is prevented and the contrast of the image is improved.
[0005]
Such black stripes are generally formed by a printing method such as screen printing (see, for example, Patent Document 1 and Patent Document 2), and black stripes are formed in concave portions between adjacent lenticular lenses. In some cases, a method of extending the light absorbing material into the recess using a squeegee (see, for example, Patent Document 3) is performed.
[0006]
On the other hand, in video display devices such as projection televisions, in recent years, there has been a strong demand for higher image quality and higher definition in order to cope with higher video resolution. For this reason, high resolution has also been demanded for lenticular lens sheets used as screens for projection televisions and the like, and the pitch of lenticular lenses is 0.5 mm or less, particularly 0.3 mm or less for single-sided lenticular lens sheets. Finer ones have been required (see, for example, Patent Document 4 and Patent Document 5).
[0007]
[Patent Document 1]
JP-A-8-207160
[0008]
[Patent Document 2]
JP 2000-147666 A
[0009]
[Patent Document 3]
JP 2002-169223 A
[0010]
[Patent Document 4]
Japanese Patent Laid-Open No. 3-127041
[0011]
[Patent Document 5]
JP-A-4-163113
[0012]
[Problems to be solved by the invention]
However, when black stripes are formed on the fine pitch lenticular lens sheet by a conventional printing method, due to the fine pitch of the lenticular lens, the light absorbing material remaining on the lenticular lens causes unevenness in the stripes, etc. Print spots that cause poor appearance tend to occur, and it is very difficult to form black stripes with a narrow and uniform width. Further, the method of extending the light absorbing material to the concave portion using the squeegee has a problem that a linear defect that causes a poor appearance is likely to occur due to the biting of foreign matter.
[0013]
Accordingly, an object of the present invention is to provide a method for producing a lenticular lens sheet that can form a thin black stripe having a high and high contrast and having no linear defects or uneven prints with high productivity even in a fine pitch lenticular lens sheet. It is to provide.
[0014]
[Means for solving the problems]
That is, the method for manufacturing a lenticular lens sheet according to the present invention is a method for manufacturing a lenticular lens sheet having a large number of lenticular lenses on at least an entrance surface and having black stripes on the exit surface. A light-absorbing material is supplied to the concave portion of the concavo-convex pattern formed so as to be positioned on the plate, a plate-like body is brought into contact with the emission surface, and the plate-like body is pressed against the emission surface, thereby forming a black stripe in the concave portion. It is characterized by.
[0015]
In this way, the light absorbing material is supplied to the concave portion of the concave-convex pattern formed on the light emitting surface, and the plate is pressed against the light emitting surface, so that the light absorbing material is sufficiently embedded in the concave portion and the surface is molded at the same time. Therefore, it is possible to form a black stripe having a thin and uniform width with high productivity and high in contrast and free from linear defects and printed spots.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
First, the lenticular lens sheet obtained by the manufacturing method of the present invention will be described with reference to FIG.
In the figure, (a) is a double-sided lenticular lens sheet in which the lenticular lenses 2 and 3 are formed at the same pitch on the exit surface side and the entrance surface side, and in the valleys between the lenticular lens units formed on the exit surface side. A black stripe 4 is formed. (B) is a concavo-convex pattern of concave portions formed at the same pitch as the lenticular lens 2 on the incident surface side so that the lenticular lens 2 is formed on the incident surface side and the concave portion is positioned on the light non-transmissive portion on the outgoing surface side. It is a single-sided lenticular lens sheet in which a light-absorbing material is filled, black stripes 4 are formed, and convex portions 3 are light transmitting portions.
[0017]
The present invention is suitable for manufacturing a fine pitch lenticular lens sheet having a lenticular lens pitch of 0.5 mm or less. In particular, the pitch used for an LCD projector or a DMD projector using a high-resolution liquid crystal display element is 0. It is a manufacturing method suitable for a single-sided lenticular lens sheet of 3 mm or less, and more preferably an ultrafine pitch single-sided lenticular lens sheet with a pitch of 0.08 to 0.2 mm. This is because in such a fine pitch lenticular lens sheet, the pitch of the black stripes formed on the exit surface is the same fine pitch as that of the lenticular lens.
[0018]
In the present invention, the lenticular lens and the concave / convex pattern may be formed by extruding a thermoplastic resin, but a fine pitch pattern can be manufactured with high accuracy and high productivity. As shown, the lenticular lens is formed on the incident surface of the translucent substrate 1 with an active energy ray curable resin, and the lenticular lens and the concavo-convex pattern are formed on the emission surface with the active energy ray curable resin. Yes. In particular, the concavo-convex pattern formed on the exit surface is formed by forming a photosensitive layer made of an active energy ray-curable composition on the exit surface side of the sheet on which the lenticular lens has been previously formed on the entrance surface side, and active from the entrance surface side through the lenticular lens Forming by irradiating the energy beam as substantially parallel light and curing only the portion corresponding to the light transmitting portion of the photosensitive layer and removing the uncured portion (light non-transmitting portion) improves the position accuracy of the concavo-convex pattern and increases the plaque. This is preferable because the stripe rate (BS rate) can be increased and the contrast can be improved. In this case, the photosensitive layer is not limited to the positive type as described above, and a negative type can also be used.
[0019]
The present invention supplies a light-absorbing material to the recess formed in the light-impermeable portion of the exit surface of the lenticular lens sheet as described above, and presses the plate-like body against the exit surface, thereby providing the light-absorbing material in the recess. It is characterized in that the surface is molded simultaneously with sufficient embedding and black stripes are formed in the recesses. By forming black stripes by pressing in this way, the light-absorbing material is sufficiently embedded in the recesses, so that contrast can be increased and fine pitch black can be produced without causing linear defects or printing spots. Even stripes can be formed uniformly and with good productivity.
[0020]
The embedding of the light absorbing material into the recess is performed by overlapping and pressing the plate-like body on the emission surface of the lenticular lens. At this time, it is necessary to adjust the viscosity to such an extent that the light absorbing material is sufficiently pushed into the recess, and the light absorbing material can be pressed while heating as necessary. The pressing is preferably a hydraulic press using hydraulic pressure or water pressure, but may be a mechanical press such as a toggle press or a clamp press. At this time, instead of separately providing a plate-like body, the pressing surface of the pressing device can be directly pressed as a plate-like body. Further, such a black stripe forming step may be performed in a batch method by cutting a lenticular lens sheet obtained by a continuous method, which will be described later, into an appropriate size, or in-line using a roll press or the like. You may carry out continuously.
[0021]
In the case of a batch-type flat plate press, a mirror-polished metal plate can be used as the pressing surface, carbon steel for mechanical structures, pre-hardened steel used as mold material, and stainless steel with excellent corrosion resistance. Various metal plates such as plates can be used. The surface accuracy of the pressed surface is preferably a surface roughness (Ry) of 10 μm or less and a surface waviness of 50 μm or less. In order to prevent per-pressing and to make the pressure distribution uniform during pressing, silicon rubber A rubber sheet such as a rubber sheet may be sandwiched and pressed.
[0022]
Continuous press rolls are made of commonly used ferrous materials such as carbon steel pipes for machine structures, non-ferrous metal materials such as aluminum alloys and copper alloys, and various composite materials such as carbon fiber reinforced plastics. Can be used. In particular, it is preferable to use a material that has been heat-treated in advance so that residual stress is released and not distorted by heat during machining. Moreover, you may perform surface treatments, such as hard chrome plating, for the purpose of improving the surface shape precision and performing a rust prevention process. As in the case of the flat plate press, it is preferable that the surface roughness (Ry) of the bus bar is 10 μm or less and the surface waviness is 50 μm or less.
[0023]
As a light-absorbing material, black pigment such as carbon black or black dye is dissolved in an organic solvent such as isophorone or methoxybutyl acetate to adjust the viscosity, and black pigment or black dye is added to the active energy ray curable composition. An active energy ray-curable composition or a pressure-sensitive adhesive sheet containing a black pigment can be used. The solvent-diluted black ink may take a long time for the drying process, or if the lenticular lens or concavo-convex pattern is made of active energy ray curable resin, the adhesion may be insufficient. It is preferable to use an active energy ray-curable composition or a pressure-sensitive adhesive sheet containing a dye.
[0024]
In the present invention, after forming a black stripe on the exit surface of the lenticular lens sheet, in order to give the lenticular lens sheet self-supporting properties and various functions, a light-transmitting plate-like body is bonded to the exit surface and bonded and integrated. May be. In particular, in the fine pitch lenticular lens sheet, when the thickness of the lenticular lens sheet becomes thin and the self-supporting property as a sheet is lost, or functions such as light diffusion, antireflection, and antistatic cannot be sufficiently provided. It is preferable to bond the light-transmitting plate-like body together.
[0025]
The light-transmitting plate is not particularly limited as long as it is a light-transmitting material, and a glass plate, a plastic plate, or the like can be used. In particular, a plastic plate made of an acrylic resin, a polycarbonate resin, an acrylic-styrene copolymer or the like is preferable. The thickness of the light-transmitting plate can be appropriately set according to the purpose, but is preferably about 0.1 to 5 mm. In addition, by adding a light diffusing material, a light selective absorber, etc. to the light transmissive plate-like body, or forming a light diffusing layer, an antireflection layer, an antistatic layer, etc. on the surface, various kinds of lenticular lens sheets Functions can also be added.
[0026]
In this way, when the light-transmitting plate-like body is bonded to the emission surface of the lenticular lens sheet, the active energy ray curable composition is used by using the active energy ray curable composition or the adhesive sheet as the light absorbing material. And the adhesive sheet can also act as an adhesive between the lenticular lens sheet and the light-transmitting plate, so the light-transmitting plate can be bonded simultaneously with the black stripe formation process, improving productivity Can be made. In this case, the light-transmitting plate-like body can be a plate-like body that presses against the emission surface of the lenticular lens sheet when the light-absorbing material is embedded in the recess.
[0027]
In the present invention, the above-described functions can be directly imparted to the lenticular lens sheet. For example, in the case of imparting light diffusibility, a light diffusing material is mixed in at least one of a lenticular lens, a concavo-convex pattern, and a translucent substrate, or the surface of the lenticular lens sheet is roughened, or the lenticular lens is roughened. A light diffusion layer can be formed on the surface of a lens sheet or a translucent substrate. As the light diffusing material, organic diffusing materials such as styrene-acrylic copolymer resin particles, inorganic diffusing materials such as silica particles, and the like are used. Such function addition to the lenticular lens sheet can be performed in combination with a light transmitting plate-like body having a function.
[0028]
The manufacturing method of the lenticular lens sheet of this invention is demonstrated with reference to FIG. 2 and FIG. 3 which showed the manufacturing process of the single-sided lenticular lens sheet.
In the figure, 5 is a cylindrical lens type having a lens pattern engraved with a lenticular lens pattern on its surface, and 5 ′ is a cylindrical BS type having an uneven pattern (BS pattern) for forming black stripes on its surface. Yes, metal molds made of metal such as aluminum, brass, steel, etc., resin molds made of synthetic resin such as silicon resin, polyurethane resin, epoxy resin, ABS resin, fluorine resin, polymethylpentene resin, manufactured by Ni electroforming method An electroforming mold or the like is used. In particular, it is desirable to use a metal mold from the viewpoints of heat resistance and strength. The cylindrical lens mold 5 and the cylindrical BS mold 5 ′ may form a lens pattern or BS pattern directly on the surface of the cylindrical roll, or a thin plate on which these patterns are formed is wound around a cylindrical roll and fixed. Things can also be used. The cylindrical lens mold 5 and the cylindrical BS mold 5 ′ are preferably plated with copper, nickel or the like on the surface in order to prevent various corrosions. Further, in order to make the cutting material particles uniform and fine, it is possible to form a lens pattern or BS pattern on the plated layer portion by forming a thick plating of copper, nickel, or the like.
[0029]
The lens pattern and BS pattern formed on the cylindrical lens mold 5 and the cylindrical BS mold 5 'are such that the difference in the overall width of the lenticular lens and the concavo-convex pattern formed on each surface of the lenticular lens sheet is within a predetermined range. It is preferable that the pitch of the lens pattern and the BS pattern formed in at least one of the cylindrical lens mold and the cylindrical BS mold is corrected. This difference in the overall width suppresses the axial deviation between the pair of concave and convex patterns on the exit surface side and the lenticular lens on the entrance surface side to about 1 to 3% of the lenticular lens pitch. % Is preferable.
[0030]
The cylindrical lens mold 5 is supplied with a translucent substrate 6 along the lens pattern forming surface, and the first active energy ray curing is performed between the cylindrical lens mold 5 and the translucent substrate 6. The composition 7 is supplied from the resin tank through the supply nozzle 8. A nip roll 9 for making the thickness of the supplied first active energy ray-curable composition 7 uniform is provided outside the translucent substrate 6. As the nip roll 9, a metal roll, a rubber roll, or the like is used. In order to make the thickness of the first active energy ray-curable composition 7 uniform, it is preferable that the nip roll 9 is processed with high accuracy with respect to roundness, surface roughness, etc. In that case, a rubber having a high hardness of 60 degrees or more is preferable. The nip roll 9 needs to accurately adjust the thickness of the active energy ray-curable composition 7 and is operated by a pressure adjusting mechanism. As the pressure adjusting mechanism, a hydraulic cylinder, a pneumatic cylinder, various screw mechanisms, and the like can be used, but a pneumatic cylinder is preferable from the viewpoint of simplicity of the mechanism. The air pressure is controlled by a pressure regulating valve or the like.
[0031]
After supplying the first active energy ray-curable composition 7 between the cylindrical lens mold 5 and the translucent substrate 6, the first active energy ray-curable composition 7 is exchanged with the cylindrical lens mold 5. The active energy ray irradiating apparatus 10 irradiates the active energy ray through the translucent substrate 6 while being sandwiched between the photoluminescent substrates 6 to polymerize and cure the first active energy ray curable composition 7. Then, the lenticular lens pattern formed on the lens mold is transferred to form an incident surface side lenticular lens on one surface of the translucent substrate 6. As the active energy ray irradiation apparatus 10, a chemical reaction chemical lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, a visible light halogen lamp, or the like is used. As the irradiation amount of the active energy ray, the integrated energy at a wavelength of 200 to 600 nm is 0.1 to 50 J / cm. ² It is preferable to set it as the grade which becomes. The irradiation atmosphere of active energy rays may be air or an inert gas atmosphere such as nitrogen or argon.
[0032]
Next, the translucent substrate 6 on which the lenticular lens is formed on one surface is supplied so that the other surface is in contact with the lens pattern forming surface of the cylindrical BS mold 5 ′. A second active energy ray-curable composition 7 ′ is supplied from the resin tank through the supply nozzle 8 ′ between the cylindrical BS mold 5 ′ and the translucent substrate 6. A nip roll 9 ′ operated by a pressure adjusting mechanism for making the thickness of the supplied second active energy ray curable composition 7 ′ uniform is installed outside the translucent substrate 6. After supplying the second active energy ray-curable composition 7 ′ between the cylindrical BS type 5 ′ and the translucent substrate 6, the second active energy ray-curable composition 7 ′ becomes the cylindrical BS type. In a state of being sandwiched between 5 ′ and the translucent substrate 6, the active energy beam irradiating device 10 ′ irradiates the active energy beam through the translucent substrate 6 to form a second active energy beam curable composition. The product 7 ′ is polymerized and cured to transfer the concavo-convex pattern formed in the BS type, and a concavo-convex pattern for forming a black stripe is formed on the other surface of the translucent substrate 6. Thereafter, the single-sided lenticular lens sheet 11 having a lenticular lens formed on one surface of the translucent substrate 6 and an uneven pattern formed on the other surface is peeled from the cylindrical BS mold 5 ′.
[0033]
In the present invention, the active energy ray cured product constituting the uneven shape formed on the surface of the translucent substrate 6 is particularly limited as long as it is cured with active energy rays such as ultraviolet rays and electron beams. Although it is not a thing, (meth) acrylate type resins, such as polyesters, epoxy resin, polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, etc. are mentioned, for example. Among these, (meth) acrylate resins are particularly preferable from the viewpoint of optical characteristics and the like. The active energy ray-curable compositions 7 and 7 ′ used for such a cured resin include polyvalent acrylates and / or polyvalent methacrylates (hereinafter referred to as polyvalent (meta)) in terms of handling properties and curability. The main component is a photopolymerization initiator using active energy rays and monoacrylate and / or monomethacrylate (hereinafter referred to as mono (meth) acrylate). Typical polyvalent (meth) acrylates include polyol poly (meth) acrylate, polyester poly (meth) acrylate, epoxy poly (meth) acrylate, urethane poly (meth) acrylate, and the like. These are used alone or as a mixture of two or more. Examples of mono (meth) acrylates include mono (meth) acrylates of monoalcohols and mono (meth) acrylates of polyols. The viscosity of the active energy ray-curable compositions 7 and 7 ′ when supplied to the cylindrical lens molds 5 and 5 ′ is preferably a viscosity in the range of 20 to 3000 mPa · S, more preferably 100 to 1000 mPa · s. The range of S.
[0034]
The translucent substrate 6 used in the present invention is not particularly limited as long as it is a material that transmits active energy rays such as ultraviolet rays and electron beams, and a flexible glass plate or the like can be used. Transparent resin sheets and films such as polyester resins, acrylic resins, polycarbonate resins, vinyl chloride resins and polymethacrylimide resins are preferred. In particular, polymethyl methacrylate having a low surface reflectance, a mixture of polymethyl acrylate and a polyvinylidene fluoride resin, a polycarbonate resin, a polyester resin such as polyethylene terephthalate, and the like are preferable. Although the thickness of the translucent substrate 6 varies depending on the application, a thickness of about 50 μm to 5 mm is usually used, and preferably about 50 to 500 μm. In addition, in order to improve the adhesiveness with the lenticular lens and uneven | corrugated pattern formed in the surface, what performed the adhesive improvement process, such as an anchor coat process, on the surface is preferable for the translucent base material 6. FIG.
[0035]
The obtained single-sided lenticular lens sheet is cut into an appropriate size, and as shown in FIG. 3, the light absorbing material 4 is embedded in the concave portions of the concave-convex pattern 3 ′ to form black stripes. The lenticular lens sheet in which the light absorbing material 4 is supplied to the concave portion of the concavo-convex pattern 3 ′ formed on the emission surface is installed in the press device in a state where the light transmissive plate 12 is superimposed on the emission surface. Between the lenticular lens sheet and the pressing device, a metal mirror plate 12 is installed via a rubber sheet 14 so as to sandwich a lenticular lens sheet on which the light transmissive plate-like body 12 is superimposed.
[0036]
In this state, the light-transmitting plate-like body 12 is pressed against the emission surface of the lenticular lens sheet with a pressing device, and the light absorbing material 4 is embedded in the concave portion of the concave / convex pattern 3 ′ of the lenticular lens sheet, and the surface is molded simultaneously with black stripes. Is formed. At this time, by using an adhesive material as the light absorbing material, the light transmissive plate 12 can be bonded and integrated with the lenticular lens sheet at the same time. The press pressure is adjusted so that the light-absorbing material 4 is sufficiently embedded in the concave portion and the formed lenticular lens is not deformed or damaged. Usually, the pressure is 50 to 300 kgf / cm at the gauge pressure. ² Range. Further, for the purpose of adjusting the viscosity of the light-absorbing material 4 and bonding the light-transmitting plate-like body 12, it can be pressed while heating. Furthermore, when using an active energy ray-curable composition as the light-absorbing material 4, it is preferable to polymerize and cure the light-absorbing material 4 by irradiating active energy rays in a pressed state or after the pressing step. Also in this case, the light transmissive plate-like body 12 can be bonded and integrated with the lenticular lens sheet simultaneously with the formation of the black stripe.
[0037]
The lenticular lens sheet of the present invention thus produced can be used as a projection screen for a projection TV or the like alone or in combination with a Fresnel lens sheet or a diffusion sheet.
[0038]
【Example】
Hereinafter, the present invention will be described specifically by way of examples.
Example 1
A flat plate mold in which a lenticular lens pattern with a pitch of 0.15 mm and a concave / convex pattern with a pitch of 0.15 mm are formed on the surface of two JIS brass type 3 plates each having a thickness of 2 mm and 480 mm × 400 mm is wound around a metal roll and fixed. A cylindrical lens mold and a cylindrical BS mold were produced.
[0039]
The obtained cylindrical lens mold 5 and cylindrical BS mold 5 ′ were arranged in parallel with an interval of 0.2 mm as shown in FIG. Servo motors were respectively attached to the cylindrical lens mold 5 and the cylindrical BS mold 5 ′. Further, an NBR rubber roll 9 having a rubber hardness of 80 ° was disposed so as to be close to the cylindrical lens mold 5 and the cylindrical BS mold 5 ′. A 100 μm thick polyethylene terephthalate film 6 that is slightly wider than the cylindrical lens mold 5 is supplied, passed between the cylindrical lens mold 5 and the rubber roll 9 along the cylindrical lens mold 5, and connected to the rubber roll 9. The translucent substrate 6 was nipped between the rubber roll 9 and the cylindrical lens mold 5 by a cylinder. The operating pressure of the pneumatic cylinder at this time was 0.1 MPa. An SMC air cylinder having an air tube diameter of 32 mm was used as the pneumatic cylinder.
[0040]
In the first ultraviolet curable composition 7, a refractive index adjusting component, a catalyst, and the like were mixed in advance and charged into a resin tank. All portions of the resin tank in contact with the first ultraviolet curable composition 7 were made of SUS304. Moreover, in order to control the liquid temperature of the 1st ultraviolet curable composition 7 to 40 degreeC +/- 1 degreeC, the warm water jacket layer is installed, and the warm water adjusted to 40 degreeC with the temperature controller is used for a warm water jacket layer. The liquid temperature of the ultraviolet curable composition 7 in the resin tank was made constant. Furthermore, bubbles generated at the time of charging were removed and removed by making the inside of the resin tank into a vacuum state with a vacuum pump.
[0041]
The 1st ultraviolet curable composition 7 is as follows, and a viscosity is 600 mPa * S / 25 degreeC.
45 parts by weight of phenoxyethyl acrylate
(Biscoat # 192 manufactured by Osaka Organic Chemical Industry Co., Ltd.)
55 parts by weight of bisphenol A-diepoxy-acrylate
(Epoxy ester 3000A manufactured by Kyoeisha Yushi Chemical Co., Ltd.)
2-Hydroxy-2-methyl-1-phenyl-propan-1-one
(Darocur 1173 manufactured by Ciba Geigy) 1.5 parts by weight
Adjusted.
[0042]
Once the inside of the resin tank is returned to normal pressure and sealed, air pressure of 0.02 MPa is applied to the resin tank, and the valve at the bottom of the resin tank is opened to control the temperature of the first ultraviolet curable composition 7. Then, it was supplied between the cylindrical lens mold 5 and the polyethylene terephthalate film 6 from the first supply nozzle 8 which was also temperature controlled. As the first supply nozzle 8, an AV101 valve manufactured by Iwashita Engineering Co., Ltd., to which an MN-18-G13 needle was attached, was used. While rotating the cylindrical lens mold 5 at a speed of 1.0 m / min, the ultraviolet irradiating device with the first ultraviolet curable composition 7 sandwiched between the cylindrical lens mold 5 and the polyethylene terephthalate film 6 10 was irradiated with ultraviolet rays, the first ultraviolet curable composition 7 was polymerized and cured, and an exit surface lenticular lens was formed on one surface of the polyethylene terephthalate film 6. The ultraviolet irradiation device 10 has an ultraviolet intensity of 120 W / cm, and has a capacity of 9.6 kW, an ultraviolet irradiation lamp manufactured by Western Quartz, a cold mirror type parallel light reflector, and a power source.
[0043]
Next, a polyethylene terephthalate film 6 having an exit surface lenticular lens formed on one surface thereof, and the cylindrical BS mold 5 ′ so that the other surface of the polyethylene terephthalate film 6 is in contact with the lens pattern forming surface of the cylindrical BS mold 5 ′. The polyethylene terephthalate film 7 was nipped between the rubber roll 9 'and the cylindrical BS mold 5' by a pneumatic cylinder connected to the rubber roll 9 '. The operating pressure of the pneumatic cylinder at this time was 0.1 MPa.
[0044]
The second ultraviolet curable composition 7 ′, which is the same as the first ultraviolet curable composition 7, was previously mixed with a refractive index adjusting component, a catalyst, and the like, and charged into a resin tank. Furthermore, bubbles generated at the time of charging were removed and removed by making the inside of the resin tank into a vacuum state with a vacuum pump.
[0045]
Once the inside of the resin tank is returned to normal pressure and sealed, an air pressure of 0.02 MPa is applied to the resin tank, and a valve at the bottom of the resin tank is opened, so that the second ultraviolet curable composition 7 ′ is heated to a temperature. It was supplied between the cylindrical BS mold 5 ′ and the polyethylene terephthalate film 6 from the second supply nozzle 8 ′ which was also temperature controlled through a controlled pipe. The second UV curable composition 7 ′ is cylindrical BS while rotating the cylindrical BS mold 5 ′ at a speed of 2.0 m / min with a 0.2kW geared motor (reduction ratio 1/200) manufactured by Mitsubishi Electric. In a state of being sandwiched between the mold 5 ′ and the polyethylene terephthalate film 6, ultraviolet rays are irradiated from the ultraviolet irradiation device 10 ′ to polymerize and cure the second ultraviolet curable composition 7 ′, and the incident surface lenticular lens is made into a polyethylene terephthalate film. 6 on one side. Thereafter, the mold was released from the cylindrical BS mold 5 ′ to obtain a single-sided lenticular lens sheet 11 in which a lenticular lens was formed on one surface and an uneven pattern for forming a black stripe was formed on the other surface. The rubber roll 9 ′, the air cylinder, the resin tank, the supply nozzle 8 ′, and the ultraviolet irradiation device 10 ′ used in the uneven pattern forming process were the same as those used in the lenticular lens forming process. .
[0046]
Next, as shown in FIG. 3, a black adhesive sheet (532, manufactured by Nitto Denko Corporation) having a thickness of 60 μm is supplied to the recesses of the uneven pattern 3 ′ of the obtained lenticular lens sheet, and further, a thickness of 2 mm and a haze value of 55 % Acrylic plates were stacked. 70 mm is sandwiched between two stainless steel mirror plates 13 having a thickness of 2 mm on both sides of a lenticular lens sheet on which an acrylic plate 12 is superposed, and is installed in a hydraulic press machine having a cylinder diameter of 250 mm through a silicon rubber sheet 14 having a thickness of 3 mm. Gauge pressure 100kgf / cm while heating to ℃ ² Pressed.
[0047]
The obtained lenticular lens sheet was bonded and integrated with an acrylic plate, and black stripes having no appearance defect such as streaks were formed in the concave portions of the concave and convex pattern. Furthermore, when the image was observed as a projection television projection screen in combination with a Fresnel lens sheet, a high-definition image with high contrast and high resolution was observed.
[0048]
Example 2
Using a UV curable composition containing a black pigment as a light-absorbing material (FIL-915TC manufactured by Teikoku Ink Co., Ltd.), after pressing, an ultraviolet lamp having an irradiation intensity of 6.4 kW (80 W / cm manufactured by Western Quartz) 3 Using a book, UV light passes through an acrylic plate and the integrated light quantity is 3000 mJ / cm. ² A lenticular lens sheet was produced in the same manner as in Example 1 except that the light-absorbing material was polymerized and cured by irradiation so that the wavelength was about 37 nm.
[0049]
The obtained lenticular lens sheet was bonded and integrated with an acrylic plate, and black stripes having no appearance defect such as streaks were formed in the concave portions of the concave and convex pattern. Furthermore, when the image was observed as a projection television projection screen in combination with a Fresnel lens sheet, a high-definition image with high contrast and high resolution was observed.
[0050]
Comparative Example 1
A light-absorbing material is supplied to the end of the concavo-convex pattern using a screen printing machine (SSP860AN manufactured by Tokai Screen Co., Ltd.), and is supplied to the concave portion while being extended using a silicon rubber squeegee knife, and then irradiated with ultraviolet rays. A lenticular lens sheet was produced in the same manner as in Example 2.
[0051]
The obtained lenticular lens sheet had an appearance defect in which a streak-like stripe pattern was observed in a direction parallel to the longitudinal direction of the lenticular lens. Furthermore, when the image was observed as a projection screen of a projection television in combination with a Fresnel lens sheet, streak-like appearance defects were observed.
[0052]
【The invention's effect】
In the present invention, the light absorbing material is supplied to the concave portion of the uneven pattern formed on the emission surface, and the plate is pressed against the emission surface, so that the light absorbing material is sufficiently embedded in the concave portion and the surface is molded at the same time. Therefore, it is possible to provide a method for producing a lenticular lens sheet that can form a black stripe having a high contrast and a thin and uniform width free of linear defects or printed spots with high productivity.
[Brief description of the drawings]
FIG. 1 is a schematic partial sectional view of a lenticular lens sheet of the present invention.
FIG. 2 is a schematic view showing a method for producing a lenticular lens sheet of the present invention.
FIG. 3 is a schematic view showing a pressing process of the lenticular lens sheet of the present invention.
[Explanation of symbols]
1 Translucent substrate
2 Entrance lenticular lens
3 Outgoing surface lenticular lens
3 'uneven pattern
4 Black stripe
5 Cylindrical lens type
5 'Cylindrical BS type
6 Polyethylene terephthalate film
7, 7 'UV curable composition
8,8 'supply nozzle
9, 9 'rubber roll
10, 10 'UV irradiation equipment
11 Lenticular lens sheet
12 Light transmissive plate
13 Metal mirror plate
14 Rubber sheet

Claims (8)

In a method of manufacturing a lenticular lens sheet having a plurality of lenticular lenses at least on the entrance surface and black stripes on the exit surface, light is absorbed in the recesses of the concavo-convex pattern formed so that the recesses are positioned on the light-impermeable portion on the exit surface Black stripes are formed in the recesses by supplying a material, abutting a plate-like body on the emission surface, sandwiching the plate-like body with a rubber sheet on the emission surface, and pressing at a gauge pressure of 50 to 300 kgf / cm ² A method for producing a lenticular lens sheet.   The method for producing a lenticular lens sheet according to claim 1, wherein the lenticular lens and / or the concavo-convex pattern is made of an active energy ray curable resin.   The method for producing a lenticular lens sheet according to claim 1, wherein the light absorbing material is made of an adhesive material.   The method for producing a lenticular lens sheet according to claim 1 or 2, wherein the light absorbing material comprises an active energy ray-curable composition.   The method for producing a lenticular lens sheet according to any one of claims 1 to 4, wherein a light-transmitting plate-like body is bonded and integrated to the emission surface.   6. The method of manufacturing a lenticular lens sheet according to claim 5, wherein the light-transmitting plate-like body is bonded with the black stripe.   The method for producing a lenticular lens sheet according to any one of claims 1 to 6, wherein the convex portion of the concave-convex pattern has a quadrangular cross section.   The method for producing a lenticular lens sheet according to any one of claims 1 to 6, wherein the convex portion of the concave-convex pattern is a lenticular lens.

Images