JPWO2013187515A1 - LENS SHEET, MANUFACTURING METHOD THEREOF, AND STEREOIMAGE DISPLAY DEVICE EQUIPPED WITH THIS LENS SHEET - Google Patents

Abstract

The lens sheet manufacturing method includes a substrate disposing step of disposing a glass substrate 11 on an uncured UV curable resin composition 12b disposed in the electroforming mold 20, and the UV curable resin composition 12b being the glass substrate 11. And laminating the electroforming mold 20, the UV curable resin composition 12b, and the glass substrate 11 so as to reach the space formed by the electroforming mold 20, and UV curing the UV curable resin composition 12b. A molding step of attaching the cured UV curable resin composition 12b to the glass substrate 11, molding the cured UV curable resin composition 12b and the glass substrate into two layers, and a cured UV curable resin composition layer. A demolding step of demolding from the electroforming mold 20 together with the glass substrate 11. In the demolding step, the temperature of the glass substrate 11 is set lower than the glass transition temperature of the cured UV curable resin composition 12b.

Description

  The present invention relates to a lens sheet, a manufacturing method thereof, and a stereoscopic image display device including the lens sheet.

  Stereoscopic image display devices include a stereoscopic image display device that uses glasses and a stereoscopic image display device that does not use glasses (hereinafter also referred to as a 3D liquid crystal display device). Patent Document 1 discloses a stereoscopic image display device using a lenticular lens method, which is one of the methods of a stereoscopic image display device that does not use glasses.

JP 10-268232 A

  By the way, 3D liquid crystal display devices are required to have a smaller pixel size in order to meet the recent demand for higher brightness and higher density. For this reason, in the lens sheet used for the 3D liquid crystal display device, the arrangement pitch of the lenses is small. When this arrangement pitch is reduced, the shape of the lens sheet in which lenses are formed on a conventional resin substrate changes depending on the use environment, resulting in a dimensional change, the lens sheet being displaced from a predetermined position, and a stereoscopic image being correctly displayed. There was a problem that it could not be displayed.

  The present invention has been made in view of the above circumstances, and is a lens sheet in which a lens portion is formed on a glass substrate, more specifically, a lens sheet having a thin glass substrate, and a manufacturing method thereof, And it aims at providing a three-dimensional image display apparatus provided with this lens sheet.

In order to achieve the above object, the lens sheet according to the first aspect of the present invention comprises:
A glass substrate and a lens portion on the glass substrate;
The lens part is composed of a UV curable resin composition that is UV cured,
The glass substrate has a thickness of 0.1 to 0.3 mm.

  The UV curable resin composition preferably contains an aliphatic resin and a hydrolysis inhibitor.

  The aliphatic resin is, for example, an aliphatic urethane acrylate.

A stereoscopic image display apparatus according to a second aspect of the present invention is provided.
The lens sheet according to the first aspect of the present invention is provided.

The method for manufacturing a lens sheet according to the third aspect of the present invention includes:
A substrate placement step of placing a glass substrate on an uncured UV curable resin composition placed on a mold;
A lamination step of laminating the mold, the UV curable resin composition, and the glass substrate so that the UV curable resin composition is spread over a space formed by the glass substrate and the mold;
A molding step of curing the UV curable resin composition by attaching the cured UV curable resin composition to the glass substrate, and molding the cured UV curable resin composition and the glass substrate into two layers. When,
A demolding step of demolding the cured UV curable resin composition layer from the mold together with the glass substrate,
In the demolding step, the temperature of the glass substrate is set to a glass transition temperature or less by TMA of the cured UV curable resin composition.

  In the substrate placement step, for example, a glass substrate having a thickness of 0.1 to 0.3 mm is placed.

In the demolding step, for example, the temperature of the glass substrate is made 0 to 40 ° C. lower than the glass transition temperature by TMA of the cured UV curable resin composition.
For example, a UV curable resin composition containing an aliphatic resin and a hydrolysis inhibitor is used for the UV curable resin composition.
The glass transition temperature by TMA of the cured UV curable resin composition is, for example, 5 to 70 ° C.

  According to the present invention, it is possible to provide a lens sheet having a thin glass substrate, a manufacturing method thereof, and a stereoscopic image display device including the lens sheet.

(A) is a top view of a lens sheet, (b) is the Ia-Ia sectional view taken on the line of (a). It is an expanded sectional view of the lens sheet concerning the embodiment of the present invention. It is a figure which shows the step of the manufacturing method of a lens sheet, (a) shows an electromold preparation step, (b) shows an application | coating step, (c) shows a board | substrate arrangement | positioning step. It is a figure which shows the step of the manufacturing method of a lens sheet, (d) shows a lamination step, (e) shows a shaping | molding step, (f) shows a demolding step. It is a figure which shows the disassembled perspective view of a three-dimensional image display apparatus.

  Hereinafter, a lens sheet of the present invention, a stereoscopic image display device including the lens sheet, and a method for manufacturing the same will be described with reference to the drawings. FIG. 1 shows a lens sheet of the present embodiment, and FIG. 2 shows an enlarged sectional view of the lens sheet. 1A is a plan view of the lens sheet, and FIG. 1B is a sectional view taken along line Ia-Ia in FIG.

  As shown in FIG. 1, the lens sheet 10 includes a glass substrate 11 and a lens portion 12. In this Embodiment, as shown to Fig.1 (a), both the glass substrate 11 and the lens part 12 are formed in the rectangular shape. The glass substrate 11 is formed in a size slightly larger than the lens portion 12 and is arranged so that the four sides thereof are parallel to the corresponding four sides of the lens portion 12.

  The glass substrate 11 consists of transparent plate glass, and the thickness is 0.1-0.3 mm. If the thickness of the glass substrate 11 is 0.3 mm or less, crosstalk when used in a stereoscopic image display device can be reduced. Moreover, the damage of the glass substrate 11 can be suppressed at the time of manufacture of the lens sheet 10 as the thickness of the glass substrate 11 is 0.1 mm or more. The thickness of the glass substrate 11 is preferably 0.1 to 0.2 mm, for example, when the thickness of the lens portion 12 is 40 to 70 μm. Here, the thickness of the lens unit 12 refers to the distance (Z direction) from the bottom surface to the apex of the lens unit in contact with the glass substrate 11.

  The lens unit 12 is formed on the glass substrate 11. There is no adhesive layer between the lens portion 12 and the glass substrate 11, and the lens portion 12 is formed directly on one surface of the glass substrate 11. In the present embodiment, as shown in FIG. 2, as a usage pattern, the lens unit 12 is disposed on the light incident side on which an image or the like is incident.

  As shown in FIG. 2, a spherical or aspherical microlens 12 a is continuously and integrally formed on the surface layer portion of the lens portion 12. As the shape of the lens portion 12, a linear Fresnel lens, a circular Fresnel lens, and a prism shape can also be employed. In FIG. 2, as an example of the micro lens 12a, a plurality of cylindrical lenses having a lens pitch of 80 μm, for example, are formed on the light incident side surface of the lens unit 12. This lens pitch is appropriately set according to the pixel size of the display.

  The microlens 12a has a function of diffusing parallel light emitted from the light source toward the viewer. For this reason, the parallel light from the light incident side is diffused in the alignment direction (X direction) of the microlenses 12a while being transmitted in the optical axis direction.

  The lens unit 12 is made of a UV curable resin composition that has been UV cured. There is no restriction | limiting in particular as UV curable resin composition, According to the objective, it can select suitably from well-known things. The UV curable resin composition preferably contains an aliphatic resin and a hydrolysis inhibitor.

  As the aliphatic resin, it is preferable to use an aliphatic urethane acrylate from the viewpoint of preventing yellowing due to ultraviolet irradiation. Examples of the aliphatic urethane acrylate include polyester urethane acrylate. The addition amount of the aliphatic urethane acrylate is preferably 30 to 80 parts by mass, and more preferably 40 to 70 parts by mass with respect to 100 parts by mass of the UV curable resin composition.

  As the hydrolysis inhibitor, carbodiimide compounds, oxazolines and the like can be used, and carbodiimide compounds having high reactivity can be preferably used. Thereby, when aliphatic UV acrylate is included in UV curable resin composition, it is inferior to the heat-and-moisture resistance, the property which is easy to be hydrolyzed, and it comes to be produced stably. In addition, in order to acquire the said effect, it is preferable that the compounding quantity of a hydrolysis inhibitor shall be 0.5-5 mass parts with respect to 100 mass parts of UV curable resin compositions, and 1-2 mass parts. More preferably.

  In addition, since the UV curable resin composition is a raw material for the lens portion 12, among the UV curable resin composition that transmits at least visible light, the refractive index after curing is about 1.4 to 1.65. It is preferable to use these materials. When a material having a refractive index smaller than 1.4 is used, the microlens 12a does not have sufficient lens power and may not be able to diffuse incident light at an appropriate angle. The refractive index is larger than 1.65. This is because, when a material is used, depending on the lens shape, the light incident on the microlens 12a may be internally reflected and the transmission efficiency as a screen may be reduced.

  The cured UV curable resin composition preferably has a glass transition temperature (Tg) of 10 to 80 ° C. when measured with a dynamic viscoelasticity meter (hereinafter also referred to as DMA). More preferably, it is 50 degreeC, and it is most preferable that it is 30-50 degreeC. Further, the cured UV curable resin composition preferably has a glass transition temperature (Tg) of 5 to 70 ° C. when measured with a thermomechanical analyzer (hereinafter also referred to as TMA), and is preferably 10 to 60 ° C. More preferably, it is 5-40 degreeC, Most preferably, it is 20-40 degreeC. In the manufacturing step of the lens sheet 10 (the demolding step of the lens unit 12), the temperature of the electroforming mold and the glass substrate (hereinafter, the temperature of the electroforming mold and the glass substrate may be referred to as a work temperature) is cured. It is preferably 5 to 50 ° C. lower than the glass transition temperature (Tg) by DMA of the composition, more preferably 10 to 30 ° C., and most preferably 15 to 25 ° C. When measured by TMA, the temperature of the electroforming mold and the glass substrate is preferably set to be equal to or lower than the glass transition temperature (Tg) of the cured UV curable resin composition, and the glass transition temperature of the cured UV curable resin composition. More preferably, the temperature is 0-40 ° C. lower than (Tg), more preferably 0-30 ° C., and most preferably 0-20 ° C. Here, the workpiece temperature is a value measured from the glass substrate side in a state where the electroforming mold / cured UV curable resin composition / glass substrate is laminated in this order using a radiation temperature sensor. By adjusting the Tg of the cured UV curable resin composition by TMA and the temperature of the electroforming mold and the glass substrate 11 within such ranges, the temperature adjustment in the demolding step of the lens unit 12 is facilitated. For example, when the workpiece temperature before UV curing is 25 ° C., the workpiece temperature after UV curing is about 30 ° C. due to heat generated when the resin is cured and heat generated by UV irradiation. By making Tg by TMA of the UV curable resin composition cured at a temperature higher than this temperature by about 0 to 10 ° C., the glass substrate can be demolded in the demolding step without being damaged.

  Furthermore, the UV curable resin composition may contain a monomer for dilution, a prepolymer, a polymer, a photopolymerization initiator that generates ions or radicals when irradiated with ultraviolet rays, and the like. The properties of the UV curable resin composition before curing, during curing, and after curing can be adjusted by changing the components of such monomers, prepolymers, polymers, and photopolymerization initiators.

  Examples of the monomer for dilution include tripropylene glycol diacrylate (TPGDA), dipentaerythritol hexaacrylate (DPHA), isobornyl acrylate (IBOA), tricyclodecane dimethanol diacrylate (TCDDMDA), and PO-modified neopentyl. Glycol diacrylate (NPG (PO) 2DA), neopentyl glycol hydroxypivalate ester diacrylate (HPNDA), benzyl acrylate (BZA), phenol acrylate (PHEA), stearyl acrylate (SA), isodecyl acrylate (IDA), Benzyl acrylate (BZA), isooctyl acrylate (IOA), tetrahydrofurfuryl acrylate (THFA), 1,6-hexanediol dia Relate (HDDA), pentaerythritol triacrylate (PETA), pentaerythritol tetraacrylate (PETTA) trimethylolpropane triacrylate (TMPTA) and the like can be used. In particular, tripropylene glycol diacrylate (TPGDA) is preferably used as a monomer for dilution from the viewpoint of good dilution effect. Furthermore, tricyclodecane dimethanol diacrylate is preferably used as a monomer for dilution from the viewpoint of extremely low shrinkage during curing and suppressing lens defects.

  A prepolymer can be used in combination with the dilution monomer. For example, polyester acrylate, epoxy acrylate, urethane acrylate, or the like is used as the prepolymer. For reasons such as low volume shrinkage and flexibility, it is preferable to use a trifunctional or lower functional group, particularly a bifunctional or trifunctional one.

  The dilution monomers and prepolymers should basically contain at least one or more functional groups of atomic groups or bonding modes that cause reactivity such as vinyl groups, carboxyl groups, and hydroxyl groups. Is preferred. As such a functional group, it is preferable to use a functional group having a vinyl group such as an acryloyl group having excellent curability by ultraviolet rays.

  Examples of the photopolymerization initiator include acetophenone series, benzophenone series, Michler ketone series, benzyl series, benzoin series, benzoin ether series, and benzyl dimethyl ketal series. Other photopolymerization initiators include benzoin benzoate, α-acyloxime ester and other carbonyl compounds, tetramethylthiuram monosulfide, thioxanthones and other sulfur compounds, 2,4,6-trimethylbenzoyldiphenylphosphine oxide. And the like, and these may be used alone or in admixture of two or more.

  Furthermore, various additives can be added to the UV curable resin composition in order to control the properties and physical properties before curing, during curing, and further after curing, or the properties and physical properties of the cured product. Examples of substances that control properties and physical properties before curing include paint stabilizers (anti-gelling and anti-curing), thickeners (improving coating properties), and the like. Examples of substances that control the properties during curing include photopolymerization accelerators and light absorbers (adjustment of curing behavior). In addition, substances that control film properties after curing include plasticizers (improved flexibility), UV absorbers (improved light resistance), antioxidants (improved heat resistance), and HALS (thermal / light stabilizers). and so on.

  In addition, you may add another polymer and an oligomer to UV curable resin composition from viewpoints, such as intensity | strength, flexibility, and curl resistance. Here, types of polymers and oligomers include known ones such as polyester resins, acrylic resins, urethane resins, and epoxy resins.

  As described above, the lens sheet 10 of the present invention is a lens sheet in which a lens portion is formed on a glass substrate 11 having a thickness of 0.1 to 0.3 mm. Further, the arrangement pitch of the lens portions 12 can be reduced. When this lens sheet 10 is used in the stereoscopic image display device 100, it is possible to meet the demand for higher density without being affected by the use environment, and the glass substrate 11 is a thin plate of 0.1 to 0.3 mm. As a result, it is possible to widen the range in which stereoscopic viewing is possible, and to minimize crosstalk that occurs when viewing a stereoscopic image.

  Next, a method for manufacturing the lens sheet 10 configured as described above will be described. 3 and 4, Z1 indicates the upward direction and Z2 indicates the downward direction.

First, as shown in FIG. 3A, an electroforming mold 20 having a recess corresponding to the lens shape of the lens sheet is prepared. The electroforming mold 20 is arranged on the carrier plate 21 with the concave portion on the upper side (electroforming mold preparation step). In the present embodiment, the electroforming mold 20 is used as a mold, but a mold and a glass mold can also be used as other molds.
Next, as shown in FIG. 3B, an uncured UV (ultraviolet) curable resin composition 12 b is applied to the concave portion where the lens sheet on the upper surface of the electroforming mold 20 is molded using the coating device 30. (Application step).

  Subsequently, as shown in FIG. 3C, the glass substrate 11 is disposed on the electroforming mold 20 so that the UV curable resin composition 12b is sandwiched between the electroforming mold 20 and the glass substrate 11 (substrate). Placement step). In addition, as mentioned above, the glass substrate 11 is a transparent base material, The thickness is about 0.1-0.3 mm. Moreover, the glass substrate 11 may be subjected to primer treatment on the surface using a conventionally known silane coupling agent.

  Subsequently, for example, as shown in FIG. 4D, the electroforming mold 20, the UV curable resin composition 12b, and the glass substrate 11 are laminated using a roll 25 (laminating step). Specifically, the pair of upper and lower rolls 25 and 26 are arranged so that the UV curable resin composition 12b reaches every corner of the space formed by the concave shape of the lower surface of the glass substrate 11 and the upper surface of the electroforming mold 20. Move. The distance between the lower surface of the glass substrate 11 and the concave bottom of the electroforming mold 20 is not particularly limited, but is, for example, 40 to 70 μm.

  Then, as shown in FIG.4 (e), an ultraviolet-ray is irradiated, the UV curable resin composition 12b is hardened, and the lens part 12 is shape | molded (molding step). Specifically, the uncured UV curable resin composition 12b on the electroforming mold 20 was applied to the electroforming mold 20 by irradiating ultraviolet rays from a UV lamp 40 disposed on the glass substrate 11 side. The UV curable resin composition 12b is cured. By curing the UV curable resin composition 12b, the lens portion 12 is formed and the lens portion 12 adheres to the glass substrate 11. As a result, as shown in FIG. 2, the concave shape of the electroforming mold 20 is transferred, and the surface of the lens portion 12 becomes the shape of the microlens 12a.

  Thereafter, as shown in FIG. 4F, the lens portion 12 of the lens sheet 10 is removed from the electroforming mold 20 (demolding step).

  Here, the temperature (working temperature) at which the lens part 12 of the lens sheet 10 is removed from the electroforming mold 20 is 0 to 40 ° C. lower than the glass transition temperature (Tg) of the UV curable resin composition by TMA. Preferably, the temperature is lowered by 0 to 30 ° C, more preferably 0 to 20 ° C. Further, the temperature of the electroforming mold and the glass substrate is preferably 5 to 50 ° C. lower than the glass transition temperature (Tg) by DMA of the UV curable UV curable resin composition, more preferably 10 to 30 ° C. Preferably, it is most preferably lowered by 15 to 25 ° C. Here, the workpiece temperature is a value measured from the glass substrate side in a state where the electroforming mold / cured UV curable resin composition / glass substrate is laminated in this order using a radiation temperature sensor. This is because the lens part 12 can be easily removed from the electroforming mold 20 by setting the temperature at the time of releasing the mold within such a range. This is because, when the demolding temperature is within such a range, the cured UV curable resin composition has appropriate elasticity and hardness, so that the electroforming mold 20 is easily peeled from the resin on the glass substrate. Because. For example, when the temperature of the workpiece is extremely lower than the glass transition temperature, the resin tends to be brittle and loses an appropriate flexibility, so that the lens portion 12 on the glass substrate 11 is peeled off from the electroforming mold 20. In doing so, the glass substrate 11 (and the resin depending on how it is peeled) is broken. On the other hand, when the workpiece temperature is extremely higher than the glass transition temperature of the resin, the resin is easily rubberized and is difficult to peel from the electroforming mold 20. That is, when the resin on the glass substrate is peeled from the electroforming mold 20, it cannot be peeled due to the viscosity of the resin itself. For this reason, the glass substrate 11 is damaged when the lens portion 12 is removed from the electroforming mold 20 together with the thin glass substrate 11 having a thickness of about 0.1 to 0.3 mm by setting the work temperature within the above range. In addition, it is possible to effectively prevent lens shape defects and warpage from occurring in the UV-cured UV curable resin composition due to curing shrinkage. That is, the dimensional stability of the lens sheet 10 is improved. In this embodiment, the Young's modulus of the UV curable resin composition manufactured and UV cured in the above temperature range is 70 to 2000 MPa at 20 ° C. and 15 to 80 MPa at 40 ° C.

  Thereafter, the glass substrate 11 and the lens portion 12 attached to the glass substrate 11 are cut into a predetermined rectangular shape (see FIG. 1A) with a scriber, and the manufacture of the lens sheet 10 is completed.

  As described above, according to the method for manufacturing the lens sheet 10 of the present invention, when the lens portion 12 is removed from the electroforming mold 20, the glass substrate 11 is damaged or UV cured by curing shrinkage. It is possible to effectively prevent occurrence of lens shape defects and warpage in the curable resin composition. For this reason, the lens sheet 10 having the thin glass substrate 11 having a thickness of about 0.1 to 0.3 mm can be manufactured.

  Next, a stereoscopic image display device including the lens sheet 10 configured as described above will be described. FIG. 5 shows an exploded perspective view of the stereoscopic image display apparatus of the present invention.

  As shown in FIG. 5, the stereoscopic image display apparatus 100 includes a light source 120, an image display unit 130, and a lens sheet 10, which are arranged in this order. Note that the stereoscopic image display apparatus 100 may include an antireflection layer on the opposite side (Z1 side) of the light source 120 of the lens sheet 10.

  The light source 120 is disposed so as to be on the farthest side (Z2 side) of the stereoscopic image display device 100 as viewed from the observer. In the state where the stereoscopic image display device 100 is used, the light source 120 emits white non-polarized light toward one surface of the image display unit 130 (light source side polarizing plate 150).

  The image display unit 130 includes a light source side polarizing plate 150, an image generation unit 160, and an emission side polarizing plate 170, which are arranged in this order from the light source 120 side.

  The light source side polarizing plate 150 has a transmission axis and an absorption axis orthogonal to the transmission axis, and when non-polarized light emitted from the light source 120 is incident, the light having a polarization axis parallel to the transmission axis direction out of the non-polarized light. Transmits light and blocks light having a polarization axis parallel to the absorption axis direction.

  The image generation unit 160 includes a liquid crystal panel, and a liquid crystal layer 160c is provided between the glass substrate 160a and the glass substrate 160b. In the liquid crystal layer 160c, a right-eye image generation region 162 and a left-eye image generation region 164 are arranged in every other row. In the usage state of the stereoscopic image display device 100, a right-eye image and a left-eye image are generated in the right-eye image generation region 162 and the left-eye image generation region 164 of the image generation unit 160, respectively. At this time, when the light transmitted through the light source side polarizing plate 150 enters the right eye image generation region 162 of the image generation unit 160, the transmitted light of the right eye image generation region 162 is the image light of the right eye image (right eye image light). It becomes. Similarly, when the light transmitted through the light source side polarizing plate 150 enters the left eye image generation region 164 of the image generation unit 160, the transmitted light of the left eye image generation region 164 is the image light of the left eye image (left eye image light). It becomes.

  When the right-eye image light that has been transmitted through the right-eye image generation region 162 and the left-eye image light that has been transmitted through the left-eye image generation region 164 are incident on the output-side polarizing plate 170, the polarization axis is parallel to the transmission axis. Light is transmitted, and light whose polarization axis is parallel to the absorption axis is blocked. In this way, the image display unit 130 emits the right-eye image light and the left-eye image light as linear light whose polarization axes are parallel to each other.

  As described above, the lens sheet 10 is provided with a plurality of microlenses 12a on the surface thereof. In the present embodiment, the right-eye image generation region 162 and the left-eye image are formed in one pitch of the lens sheet 10. One generation region 164 is included. A plurality of right-eye image generation areas 162 and left-eye image generation areas 164 may be included in one pitch. The lens sheet 10 may be arranged so that the surface on which the microlens 12a is provided faces the light source 120 side. In the usage state of the stereoscopic image display apparatus 100, the light emitted from the right-eye image generation region 162 and the left-eye image generation region 164 enters the corresponding microlens 12a, and the respective light emitted from the microlens 12a is Incident on the left eye.

  In the stereoscopic image display device 100 configured as described above, since the lens sheet 10 having a lens formed on a glass substrate is used, even if the arrangement pitch is reduced, the dimensional change is not easily influenced by the environment during use. Can be minimized. Specifically, the warp of the lens sheet 10 and the displacement of the arrangement pitch can be minimized. Moreover, since the glass substrate 11 of the lens sheet 10 is thin, the width of the viewing angle that can be stereoscopically viewed can be widened, and crosstalk can be suppressed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, the technical idea of this invention is not limited to these Examples.

  First, a UV curable resin composition having the composition shown in Table 1 was prepared, and the prepared UV curable resin composition was applied to a female mold having a lens shape using a coating apparatus. Next, a glass substrate (thickness 0.2 mm, manufactured by Nippon Electric Glass Co., Ltd.) was placed on the female mold so that the applied UV curable resin composition was sandwiched between the female mold and the glass substrate. Subsequently, using a roll, the UV curable resin composition is spread to every corner of the space formed by the lens shape formed on the glass substrate and the female mold, and then the integrated light amount becomes 1000 mJ. The lens part was formed by irradiating ultraviolet rays from the glass substrate side and curing the UV curable resin composition. And the sample for evaluation of Examples 1-9 was formed by peeling a lens part with a glass substrate from a female type | mold at the workpiece | work temperature of 0-60 degreeC. The work temperature refers to the temperature at which the product is peeled from the mold. The digital radiation temperature sensor (manufactured by Keyence Corporation, FT-H10) is used to determine whether the workpiece is a female mold / cured UV curable resin composition / glass substrate. It measured from the glass substrate side in the state laminated | stacked in this order.

Evaluation samples were evaluated according to the following criteria.
(1) Wet and heat resistance (1-1) Evaluation method The sample for evaluation was allowed to stand in an atmosphere of 60 ° C and 95% RH, and the sample for evaluation after 2000 hours was visually confirmed.
(1-2) Evaluation criteria Evaluation was performed according to the following criteria. The results are shown in Table 2.
○: No change from the initial state.
Δ: The lens sheet becomes slightly cloudy.
X: Low molecular weight material bleeds out and the lens sheet becomes cloudy.

(2) Light resistance (2-1) Evaluation method The sample for evaluation was irradiated with ultraviolet rays until the integrated light quantity reached 4000 MJ, and the degree of yellowing of the subsequent sample was visually confirmed.
(2-2) Evaluation criteria The following criteria evaluated by the degree of yellowing after ultraviolet irradiation. The results are shown in Table 2.
○: No change from the initial state.
(Triangle | delta): It yellows (deteriorates) slightly from an initial state by ultraviolet irradiation.
X: Yellowing (degradation) markedly occurs from the initial state by ultraviolet irradiation.

(3) Manufacture of Young's modulus (3-1) measurement sample The measurement sample was prepared by curing the resin composition prepared in each example with ultraviolet rays so that the integrated light amount was 1000 mJ using a predetermined mold. What was left to stand at room temperature for 1 day was used as a measurement sample. The size of the measurement sample is 5 mmW × 21 mmL × 0.1 mmt.
(3-2) Measuring method
It measured using the dynamic viscoelasticity measuring machine made from Rheometric.Scientific.FE. The measurement conditions are a temperature range of −50 to 100 ° C., a temperature increase rate of 10 ° C./min, and a frequency of 1 Hz.

(4) Tg measurement by DMA
(4-1) Production of measurement sample The measurement sample was produced in the same manner as the Young's modulus measurement sample. The size of the measurement sample was 5 mmW × 21 mmL × 0.1 mmt.
(4-2) Measuring method
It measured using the dynamic viscoelasticity measuring machine made from Rheometric.Scientific.FE. The measurement conditions were a temperature range of −50 to 100 ° C., a temperature increase rate of 10 ° C./min, a frequency of 1 Hz, and a tensile mode.

(5) Measurement of Tg by TMA (5-1) Preparation of measurement sample The measurement sample is prepared by using the resin composition prepared in each example with ultraviolet rays so that the integrated light amount becomes 1000 mJ using a predetermined mold. It was cured and left standing at room temperature for 1 day. The size of the measurement sample is 3 mm × 3 mm.
(5-2) Measuring method It measured by the penetration method using the thermomechanical analyzer by Shimadzu Corporation. The measurement conditions are a temperature range of −50 to 100 ° C., a temperature rising rate of 10 ° C./min, and a load of 5 kgf.

(6) Lens shape (6-1) Production of sample for evaluation The sample for evaluation was produced in the same manner as the sample used for wet heat resistance and light resistance.
(6-2) Evaluation Method Each evaluation sample was demolded at a workpiece temperature of 0 to 60 ° C., and the surface of the evaluation sample was evaluated visually or using a loupe.
(6-3) Evaluation criteria Evaluation was performed according to the following criteria. The results are shown in Table 2.
○: There was no lens-shaped molding defect in the entire lens sheet.
(Triangle | delta): The shaping | molding defect of a lens shape was confirmed by a part of lens sheet | seat.
X: A lens-shaped molding defect was confirmed on the entire lens sheet.

(7) Demoldability (7-1) Preparation of evaluation sample The sample was prepared in the same manner as the evaluation sample used in the lens shape.
(7-2) Evaluation method About the case where each sample for evaluation was demolded at a workpiece temperature of 0 to 60 ° C, it was evaluated visually according to the following criteria. The results are shown in Table 2.
X: The glass substrate was damaged during demolding.
○: The glass substrate was not damaged and could be removed from the mold well.

  As shown in Table 2, when the workpiece temperature is removed from the male mold by setting the workpiece temperature to, for example, 10 to 30 ° C. in Example 1 and 0 to 20 ° C. in Example 2, the glass substrate A lens sheet having a thin glass substrate with a thickness of about 0.1 to 0.3 mm can be prevented from being damaged or causing a lens shape defect or warpage in the UV curable resin composition due to curing shrinkage. It was confirmed that it could be manufactured.

  Note that the present invention can be variously modified and modified without departing from the broad meaning and scope of the present invention. Further, the above-described embodiment is for explaining the present invention, and does not limit the scope of the present invention. That is, the scope of the present invention is shown not by the embodiments but by the claims. Various modifications within the scope of the claims and within the scope of the equivalent invention are considered to be within the scope of the present invention.

  This application is based on Japanese Patent Application No. 2012-136417 filed on Jun. 15, 2012. In this specification, the specification of Japanese Patent Application No. 2012-136417, the scope of claims, and the entire drawing are incorporated by reference.

  The present invention is useful for a lens sheet, a manufacturing method thereof, and a stereoscopic image display apparatus including the lens sheet.

DESCRIPTION OF SYMBOLS 10 Lens sheet 11 Glass substrate 12 Lens part 12a Micro lens 20 Electroforming mold 25, 26 Roll 30 Coating device 40 UV lamp 100 Stereoscopic image display device 120 Light source 130 Image display unit 150 Light source side polarizing plate 160 Image generation unit 160a, 160b Glass substrate 160c Liquid crystal layer 162 Image generation region for right eye 164 Image generation region for left eye 170 Output side polarizing plate 200 Antireflection layer

Claims (9)

A glass substrate and a lens portion on the glass substrate;
The lens part is composed of a UV curable resin composition that is UV cured,
The glass sheet has a thickness of 0.1 to 0.3 mm.   The lens sheet according to claim 1, wherein the UV curable resin composition includes an aliphatic resin and a hydrolysis inhibitor.   The lens sheet according to claim 2, wherein the aliphatic resin is an aliphatic urethane acrylate.   A stereoscopic image display apparatus comprising the lens sheet according to claim 1. A substrate placement step of placing a glass substrate on an uncured UV curable resin composition placed on a mold;
A lamination step of laminating the mold, the UV curable resin composition, and the glass substrate so that the UV curable resin composition is spread over a space formed by the glass substrate and the mold;
A molding step in which a UV curable resin composition cured by UV curing the UV curable resin composition is attached to the glass substrate, and the cured UV curable resin composition layer and the glass substrate are molded into two layers. When,
A demolding step of demolding the cured UV curable resin composition layer from the mold together with the glass substrate,
In the demolding step, the temperature of the glass substrate is made equal to or lower than the glass transition temperature by TMA of the cured UV curable resin composition.   6. The lens sheet manufacturing method according to claim 5, wherein a glass substrate having a thickness of 0.1 to 0.3 mm is arranged in the substrate arranging step.   The lens according to claim 5 or 6, wherein, in the demolding step, the temperature of the glass substrate is set to 0 to 40 ° C lower than the glass transition temperature by TMA of the cured UV curable resin composition. Sheet manufacturing method.   The lens sheet according to any one of claims 5 to 7, wherein a UV curable resin composition containing an aliphatic resin and a hydrolysis inhibitor is used as the UV curable resin composition. Production method.   The method for producing a lens sheet according to any one of claims 5 to 8, wherein a glass transition temperature by TMA of the cured UV curable resin composition is 5 to 70 ° C.

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