KR20080075901A - Optical sheet for display, and manufacturing method and apparatus therefor - Google Patents

Abstract

An optical sheet for display use wherein two or more optical sheets are stacked therein and the optical sheets are joined to one another on one peripheral side of each by a thermoadhesive film is to be provided. Also an optical sheet for display use wherein two or more optical sheets are stacked therein and the optical sheets are joined to one another on two or more peripheral sides of each by a thermoadhesive film is to be provided. Since the optical sheets are joined to one another on one peripheral side or two or more peripheral sides of each by a thermoadhesive film, the step of cutting each of multiple films (sheets) into the product size can be omitted, and so can be the step of stacking multiple layers of films (sheets) while positioning them. Also, it is free from a problem which derives from protective sheets, resulting in advantages in both cost and quality aspects. Moreover, it is free from a problem which arises when multiple layers of films are stacked.

Description

Optical sheet for display, and manufacturing method and apparatus therefor {OPTICAL SHEET FOR DISPLAY, AND MANUFACTURING METHOD AND APPARATUS THEREFOR}

TECHNICAL FIELD The present invention relates to an optical sheet for display, and a method and apparatus for manufacturing the same, and more particularly, to an optical sheet for display in a liquid crystal display device and the like, and a method and apparatus for manufacturing the same.

Today, liquid crystal display devices incorporating playback devices as well as laptop personal computers, mobile phones and portable liquid crystal TV receivers equipped with color liquid crystal display devices have prevented the increase in the period of time that the battery can be driven. Large power consumption of the device has been an obstacle. Most liquid crystal display devices use a backlight system that illuminates the liquid crystal layer from behind to apply light thereto, and the backlight system includes a backlight unit provided under the liquid crystal layer.

Typically, the backlight unit has a light source such as a cold cathode tube or LED, a light guide plate and a plurality of optical sheets. Optical sheets usable for this purpose include hologram sheets, polarizing sheets, antireflective sheets, light reflecting sheets, transflective sheets, diffraction grating sheets, interference filter sheets, optical filter sheets, optical wavelength conversion sheets, light diffusing sheets, and the like. . Optical sheets incorporated in the backlight unit of the liquid crystal display device include light diffusing sheets, lens sheets and the like.

Incidentally, it is essential to enhance the brightness of the liquid crystal display device in order to display a still image or a moving image clearly. In order to achieve this, it is possible to increase the amount of light of the light source, to improve various optical properties of the light diffusion sheet and the lens sheet, and the like.

However, any of the aforementioned products using liquid crystal display devices have limited power consumption to use them for a long time and have a limit in increasing the amount of light emitted from the light source. In particular, the power consumed by the backlight used in the liquid crystal display device accounts for a high percentage of the overall power consumption of the device, and minimizing this power consumed by the backlight extends the period of time during which the battery can drive the device and It is a key to enhance the practical value of any of the products described above.

However, since the visibility of the liquid crystal display may be weakened, it is not desirable to reduce the power consumption to induce a decrease in the brightness of the backlight. In view of this problem, an optical sheet for display has been proposed to improve the optical efficiency of the backlight as a method of enhancing the brightness of the liquid crystal display device without increasing the power consumed by the backlight (Japanese Patent Application Laid-open No. 7- 230001, Japanese Patent No. 3123006, Japanese Patent Application Publication No. 5-341132).

Japanese Patent Application Publication No. 7-230001, Japanese Patent No. 3123006, and Japanese Patent Application Publication No. 5-341132 disclose a light diffusion sheet for diffusing light from a light source such as a light guide plate and a lens sheet for condensing light in the front direction. In addition, an optical sheet combining the functions of the light diffusion sheet and the lens sheet is proposed. However, these lens sheets need a protective sheet to prevent these streaks because only a few streaks on their front or back side are recognizable and make these sheets unusable.

This means an extra step for adhering the protective sheet and a cost drawback due to the increase in the item of material. The additional cost is not the only problem, and the static electricity generated when the protective sheet is removed in the process of integrating the lens sheet and removing the protective sheet in the backlight assembly step causes fine-dust to occur around the attachment in the plane of the lens sheet, resulting in defects. There is also a quality problem that causes it.

In order to solve this problem, the applicant forms a laminated sheet comprising a plurality of optical sheets on which another optical sheet is laminated on one optical sheet, for example, the front of each lens sheet or It is proposed to form a laminated sheet composition of the diffusion sheet laminated over at least one side of the back surface, and use the diffusion sheet as a protective film to prevent damage on the lens sheet or dust adhesion on the plane of the lens sheet. Suggest to use.

Examples of laminated sheet constructions are disclosed in Japanese Patent Application Publication No. 2004-184575, in which a reflective polarizing film, a retardation film, and a transflective layer are laminated in any desired order, and an absorbing polarizing film is laminated outside these three layers. Semi-transmissive polarizing film. This configuration having five film layers between the light source device and the liquid crystal cell serves to enhance the brightness of the screen or to lower the power consumption.

In addition, Japanese Patent Application Publication No. 7-230001, Japanese Patent No. 3123006, and Japanese Patent Application Publication No. 5-341132 disclose a film in which the functions of a single light diffusing film and a lens film are integrated.

However, for any of the foregoing conventional configurations, laminating numerous films requires many and complex manufacturing steps correspondingly, which inevitably increases manufacturing costs.

Planar lenses, such as lenticular lenses and prism sheets, whose surfaces are susceptible to damage and deterioration, are typically delivered with the protective sheet applied to the surface, whereas such protective film is damaged when removed from the planar lens, It is undesirable because it is economical and increases manufacturing costs. In addition, unnecessary work of removing the protective sheet from the planar lens leads to a decrease in the productivity. In addition, the static electricity generated when the protective sheet is removed from the planar lens is likely to contaminate the planar lens through dust or the like, which represents a problem of quality deterioration.

In addition, when a large number of films (sheets) are laminated, the films may often be damaged by scraping due to friction, thermal expansion or contraction occurring during lamination, or rubbing during processing.

In addition, due to mismatching (distortion or, increasing the thickness of the individual films (improving the stiffness) or inducing many defects, including design limitations and additional costs, between a plurality of films resulting from thermal expansion or shrinkage It may be necessary to take some other measures to correct the deformation (such as curling).

In addition, where the plurality of optical sheets are integrated through welding, for example, the molten portion of the optical sheet may protrude out of the laminated sheet component and thus the size of the laminated sheet component may change after such bonding. . The difference in thermal expansion or contraction among different types of the plurality of optical sheets is another problem that may lead to bending of the laminated laminate sheet constructions. Changes in laminated sheet construction at design size or bending thereof may have a negative effect on optical performance.

The object of the invention attempted in this situation is to provide a display suitable for producing high quality sheet-shaped laminates for use in display applications, such as liquid crystal display elements, for example, through simpler processes at lower cost than conventional products. To provide an optical sheet for use, and a method and apparatus for producing the same.

Another object of the invention attempted in such a situation is that the dimensional accuracy of the laminated sheet construction is maintained where the plurality of optical sheets are laminated and bonded at at least one position around the respective laminated sheet construction and the optical sheets are The present invention provides a laminated sheet for display and a method and apparatus for manufacturing the same, which can be prevented from being bent.

In order to achieve the above object, the present invention provides an optical sheet for display, in which two or more optical sheets are laminated therein and the optical sheets are bonded to each other on each one peripheral side by a heat-adhesive film. .

The present invention also provides an optical sheet for display, in which two or more optical sheets are laminated therein, and the optical sheets are bonded to each other on each of two or more peripheral sides by a heat-adhesive film.

According to the invention, since the optical sheets are bonded to each other on each one peripheral side or on two or more peripheral sides by the heat-adhesive film, the step of cutting each of the plurality of films (sheets) into the product size can be omitted and Thus, this step of cutting can be the step of laminating a plurality of layers of the film (sheet) while placing them. It is also free from the above-mentioned problems derived from the protective sheet, and therefore has an advantage in terms of both cost and quality. It is also free from the above-mentioned problems that occur when a plurality of layers of the film are laminated.

In addition, mismatching between a plurality of films due to thermal expansion or contraction is mitigated by the heat-adhesive film layer, so that damage (such as distortion or warpage) due to mismatching hardly occurs. Thus, it is unnecessary to increase the thickness of the individual film (improve stiffness), or to take any other measures to correct such damage, thus leading to advantages due to reduced design constraints and cost savings. . The details and various advantages of this thermal adhesive film are described in detail below.

In view of these advantages, high quality sheet-shaped laminates used for display applications, such as liquid crystal display elements, can be manufactured in a simpler process, which is less expensive and simpler in accordance with the present invention than such conventional products.

Incidentally, the optical sheet (optical film) is usually a diffusion sheet, a polarizing plate (polarizing sheet film), various lens sheets (lenticular lens, fly's eye lens, prism sheet, etc.), antireflection sheet, light reflecting sheet, semitransmissive sheet. Protection sheet which is a common name for all kinds of optically functional sheets, including diffraction grating sheets, interference filter sheets, color filter sheets, optical wavelength conversion sheets and hologram sheets, but which rarely performs any optical function (protection Film) is also covered by this term.

According to the invention, the heat-adhesive film is preferably located on the peripheral side or sides between the optical sheets. This configuration in which the thermally adhesive film is located between the optical sheets is easier to assemble, and the clearance between the optical sheets can be more easily uniform.

According to the present invention, it is preferable that the heat-adhesive film is disposed at a position from 2 to 4 mm from the edge of the optical sheet. Placing the heat-adhesive film at such a position allows sufficient adhesion to be secured without substantially adversely affecting the viewing range of the display device.

According to the invention it is preferred that the heat-adhesive film is adhered to the peripheral side or to the end face of the optical sheet of the sides. This configuration in which the heat-adhesive film is adhered to the end face of the optical sheet can facilitate assembly, and although the heat-adhesive film needs to be removed, this removal can be easily achieved.

According to this invention, it is preferable that the thickness of the heat bonding film after bonding is 0.1 mm or less. This thickness can make the gap between the optical sheets more easily uniform, and hardly any problem that can cause interference fringes occurs.

According to the present invention, the heat-adhesive film is preferably a polyester film. The material of the heat-adhesive film may be polyamide, polyurethane or ethylene vinyl acetate (EVA), but the polyester film can achieve high tack and high flexibility at the same time.

According to the invention it is preferred that the optical sheet comprises a diffusion sheet. In addition, the optical sheet preferably includes a lens sheet on which the convex lenses formed in the uniaxial direction are adjacent to each other and disposed substantially over the entire surface. Incidentally, the "lens sheet in which the convex lenses formed in the uniaxial direction are disposed substantially all over the surface adjacent to each other" is typically a lenticular lens or prism sheet, and may be a diffraction grating.

Further, according to the present invention, it is preferable that the optical sheet includes two or more sheets having the same optical performance. In cases where two or more sheets of the same optical performance are included, for example, two lens sheets in which convex lenses formed in one axial direction are adjacent to each other and disposed substantially throughout the portion may be arranged in a direction perpendicular to the axes of the convex lenses. In the case of lamination, or in the case where the diffusion sheets are laminated on the front and rear surfaces of the laminate of lens sheets. Incidentally, although the lenses are "laminated in the direction orthogonal to the axes of the convex lenses", the angle may be adjusted to some extent to prevent moire fringes and the like.

In order to achieve the above object, the present invention provides that at least one optical sheet is laminated, and formed at one or more positions of the edge of the laminate in which the through holes or through holes are laminated, and the optical sheets are formed in the through holes or through holes. To provide an optical sheet for display.

To achieve these objects, the present invention provides a table holding two or more laminated optical sheets; An elevating stage for elevating a plurality of acicular members; And an apparatus for manufacturing an optical sheet for display provided with a heating device for heating the needle-shaped member, wherein the heated needle-shaped member can form through holes at a plurality of positions on the edge of the stack of the optical sheet. have.

According to the invention, the step of cutting the plurality of films (sheets) to product size is omitted since the through holes are formed at one or more positions on the edge of the stack of optical sheets and the optical sheets are engaged with each other by the through holes. Thus, this cutting step may be the step of laminating a plurality of layers of the film (sheet) while placing them. In addition, this is free from the above-mentioned problems originating from the protective sheet, which brings advantages in both cost and quality. It is also free from the above-mentioned problems that occur when a plurality of layers of the film are laminated.

In addition, mismatching between a plurality of films due to thermal expansion or contraction is mitigated by engagement of the through holes or through holes formed at intervals, and thus damage (such as distortion or warpage) due to mismatching is avoided. Almost never occur. Therefore, it is not necessary to increase the thickness of the individual film (improve stiffness) or take any other measures to correct such damage, which results in the reduction of design constraints and cost savings.

Due to this advantage, high quality sheet-shaped laminates used for displays such as liquid crystal display elements can be produced in a simpler process at a lower cost in accordance with the present invention than such conventional products.

Incidentally, the optical sheet (optical film) according to the present invention is the same as described above.

According to the invention, the through holes or through holes are preferably formed by melting the optical sheet. If the through holes or through holes are formed by melting the optical sheet, the melt portions of the sheet can be more easily engaged with each other, which results in a better state of engagement between the optical sheets. Although the use of the needle-like member described below is preferable for melting the optical sheet, other known methods such as laser treatment and ultrasonic heating may also be used.

According to the invention, the through holes or through holes are preferably arranged at a position of 3 mm or less from the edge of the optical sheet. Placing the through holes or through holes in this position allows for a sufficiently tight fit to be secured without substantially adversely affecting the viewing range of the display device. Incidentally, the position of any through hole spaced up to 3 mm from the edge means that the edge of the through hole inside the sheet is 3 mm or less away from the edge of the sheet.

According to the invention, the diameter of the through hole or through holes is preferably 0.3 to 2.0 mm. If the diameter of the through hole is within this range, a sufficiently firm engagement can be ensured, and this optical sheet can be relatively well prevented from the problem of large distortion (heat damage) and interference fringes.

According to the present invention, it is preferable that the through holes or through holes are formed by heated needle-shaped members. The use of such heated needle-shaped members facilitates mass production of industrial scales. In addition, no consumable items are needed which promote manufacturing costs. In addition, the absence of protrusions due to melting of the sheet as a result provides an advantage in terms of quality.

According to the present invention, the density of the through holes in the mutually engaging portions of the optical sheet is preferably at least 2 per cm 2. If the density of the through-holes is within this range, a sufficiently firm fit can be ensured. Incidentally, in this connection, the through-hole density means a share obtained by dividing the number of through-holes by the area surrounding the plurality of through-holes in a state where a plurality of through-holes are formed adjacent to each other. The density of the through-holes is more preferably 4 or more per cm 2, and even more preferably 6 or more per cm 2.

According to the present invention, the mutually engaging portions of the optical sheet are preferably pressed by the retaining member from above and below thereof when the through holes or through holes are formed by the heated needle-like member. Compression of the interlocking portions due to the retaining member makes it difficult for the melted portion of the sheet to enter between the optical sheets, making it difficult to cause distortion or interference fringes of the sheet.

According to the present invention, it is preferable that insertion holes or holes or insertion grooves or grooves allowing the needle-shaped member to be inserted are formed in one or both of the retaining members. Such insertion holes or holes or insertion grooves or grooves that allow the needle-shaped member to be inserted enable the edges of the needle-shaped member to be compressed, making the melt of the sheet more difficult to enter between the optical sheets, resulting in distortion of the sheet. Or make it more difficult to cause interference fringes.

According to the present invention, the mutually engaging portions of the optical sheet include an upper retaining member and a needle-shaped member in which an insertion hole is formed to allow the needle-shaped member to be inserted when the through-hole or the through-holes are formed by a heated needle-shaped member. It is preferred that the insert groove be pressed between the formed lower retaining members to allow the to be inserted. Since the edges of the needle-like member can be squeezed in this mode, this may make it more difficult for the melt portion of the sheet to enter between the optical sheets, making it more difficult to cause distortion or interference fringes of the sheet.

According to the present invention, it is preferable that the width of the bore of the insertion hole and / or the insertion groove is 1.02 to 4 times the diameter of the needle-shaped member. Since these holes and / or groove widths cause the edges of the needle-like members to be compressed without gaps, making the melt of the sheet more difficult to enter between the optical sheets and making the sheet distortion or interference fringes more difficult . Incidentally, the hole and / or groove width is more preferably 1.5 to 3 times the diameter of the needle-shaped member, and even more preferably 1.8 to 2.5 times the diameter of the needle-shaped member.

According to the invention, the optical sheet preferably comprises a diffusion sheet. Further, according to the present invention, it is preferable that the optical sheet includes a lens sheet disposed thereon, and a lens sheet disposed on substantially the entire portion adjacent to each other with convex lenses formed in the uniaxial direction. Incidentally, the "lens sheet in which the convex lenses formed in the uniaxial direction are disposed substantially in the whole part adjacent to each other" is usually a lenticular lens or prism sheet, and may be a diffraction grating or the like.

According to the invention, the optical sheet preferably comprises two or more sheets of the same optical performance. Examples have already been described in which two or more sheets of the same optical performance are included.

In order to achieve the above object, the present invention manufactures an optical sheet for display comprising a bonding step in which a laminated sheet component formed by laminating three or more optical sheets is bonded at at least one position of its edge to integrate the component. Wherein only the optical sheet constituting the highest layer of the laminated sheet constitution and the optical sheet constituting the lowest layer are bonded in the bonding step.

According to the present invention, in the bonding step in which a laminated sheet component formed by laminating three or more optical sheets is bonded to at least one position of its edges to integrate the component, the optical sheet and the lowest layer constituting the highest layer of the laminated sheet component are formed. Only the constituting optical sheet is bonded. This allows the optical sheet for display, which is a laminated sheet constitution, to be integrated in such a form as to hold the optical sheet constituting the intermediate layer between the highest and lowest optical sheets. Thus, the optical sheet of the interlayer is only held between, but not bonded to, the top and bottom optical sheets, and even when thermal expansion or contraction occurs between the plurality of optical sheets, the laminated sheet composition (such as distortion or warpage) ) Has almost no tolerable damage.

By bonding only the top and bottom layers of optical sheets, even if they are melt-bonded, it is possible to maintain less generation of molten material than when the entire laminated sheet composition, including the interlayer, is melt-bonded. This makes it more difficult for the molten material to protrude out of the laminated sheet construction, thus eliminating the problem of changes in the size of the laminated sheet construction after bonding.

Incidentally, the number of optical sheets constituting the intermediate layer is not limited to one but may be more than one. Further, although the number of positions on their edges at which the highest and lowest layers of optical sheets are bonded may be appropriately selected within a range in which the intermediate layer may not be peeled off during the processing of the laminated sheet construction or in any other case, It is desirable to be as small as possible in view of reducing bending.

According to the present invention, it is preferable that only the top and bottom optical sheets are bonded by forming an intermediate layer of optical sheets between the top and bottom layers in a planar size smaller than the top and bottom optical sheets. The mode in which only the highest and lowest layers of optical sheets are bonded is a mode in which an intermediate layer of the optical sheets between the highest and lowest layers is formed in a smaller plane size than those of the highest and lowest layers. By forming the intermediate layer of the optical sheets into a smaller plane size than the optical layers of the highest and lowest layers, an annular gap with dimensionally different portions between the highest and lowest layers on the one hand and dimensionally different portions of the intermediate layer on the other hand gaps are formed, and the molten material generated in the bonding process is accommodated in this gap, which makes it difficult for the molten material to protrude to the outside of the laminated sheet component. Incidentally, the most common planar shapes of the top layer, the bottom layer and the middle layer are rectangular, but there are no specific limitations on these shapes, only that their shapes are similar.

According to the invention, it is preferred that the intermediate layer of optical sheets is included internally by bonding the entire edges of the top and bottom layers of optical sheets. To form these edges in a bag shape and to include an intermediate layer inside the bag, the entire edges of the top and bottom layers of optical sheets are bonded together. This serves to prevent the interlayer of the optical sheets from falling off when the laminated sheet construction is processed.

According to the invention, it is preferred that the notch is cut at at least one position of the edge of the intermediate layer of the optical sheets between the top and bottom layers, and only the top and bottom layers of optical sheets are bonded through this notch. There is another preferred mode for bonding the highest and lowest layers of optical sheets, in which the notch is cut at at least one position of the edge of the intermediate layer of the optical sheets, through which only the highest and lowest layers of optical sheets are bonded. By cutting the notch in at least one position of the edges of the optical sheets in this way, it becomes more difficult for the molten material produced in the bonding process to be accommodated in this notch and the molten material protrude out of the laminated sheet construction.

According to the present invention, it is preferable that a hole is formed at at least one position of the edge of the intermediate layer of the optical sheets between the highest layer and the lowest layer, and only the optical sheet of the highest layer and the lowest layer is bonded through the hole. This is for bonding only the top and bottom optical sheets, in which a hole is formed at at least one position of the edge of the intermediate layer of the optical sheets between the top and bottom layers, and only the top and bottom optical sheets are bonded through the hole. Another preferred mode is By drilling a hole in at least one position of the edge of the intermediate layer of the optical sheets in this manner, the molten material produced in the bonding process is accommodated inside the hole, and it becomes more difficult for the molten material to protrude out of the laminated sheet component. . Incidentally, the position of the hole formed in the intermediate layer is preferably at four corners (corners) of the rectangular optical sheet.

According to this invention, it is preferable that the highest layer and the lowest layer of three or more optical sheets are the same kind of optical sheet. By using the same type of optical sheet for the top and bottom layers in this manner, thermal expansion or contraction is made uniform and it becomes even more difficult for the laminated sheet construction to bend.

According to the present invention, it is preferable that the three or more optical sheets include a lens sheet and a diffusion sheet and a diffusion sheet disposed at the highest and lowest layers. This means that the lens sheet can be protected by constituting the laminated sheet constitution of the lens sheet and the diffusion sheet as a type of optical sheet constituting the laminated sheet, and disposing the diffusion sheet in the highest layer and the lowest layer. Incidentally, the intermediate layer is not limited to the lens sheet but may be a combination of the lens sheet and the diffusion sheet.

According to the present invention, the optical sheet of the intermediate layer is preferably bonded to a part of the optical sheet of the highest layer and / or the lowest layer. This means that if the intermediate sheet is peeled off or replaced during the processing of the laminated sheet construction in which the optical sheet of the intermediate layer is held between the highest and lowest optical sheets, the optical sheet of the intermediate layer is in part of the highest and / or lowest layer optical sheet. It is preferable to join.

To achieve the above object, the present invention provides an optical sheet for display integrated by bonding at least one position of an edge of a laminated sheet component formed by laminating three or more optical sheets, wherein the highest layer of the laminated sheet component is provided. Only the optical sheet and the optical sheet of the lowest layer are bonded.

An optical sheet for display, such as the optical sheet for display according to the present invention, in which only the uppermost optical sheet and the lowest optical sheet of the laminated sheet constituent are bonded and the intermediate layer is hardly bonded, a thermal expansion or expansion between a plurality of optical sheets or Even if there is a slight difference in shrinkage, almost no damage is allowed to occur (such as distortion or warpage). Also, it is more difficult for the molten material to protrude out of the laminated sheet construction, and the dimensional accuracy of the laminated sheet construction can be maintained well.

In the optical sheet for display according to the present invention, an intermediate layer of optical sheets is formed in a plane size smaller than the highest and lowest layers of optical sheets between the highest and lowest layers, and the intermediate layers of the optical sheets cover the entire edges of the optical sheets of the highest and lowest layers. It is preferable to contain in the inside by bonding. This aim is to safely prevent the intermediate layer of optical sheets from being peeled off during the processing of the laminated sheet construction.

According to the invention, it is preferable that the notch is cut at at least one position of the edge of the intermediate layer of the optical sheets between the highest and lowest layers, and through this notch only the highest and lowest layers of optical sheets are bonded.

According to the present invention, it is preferable that a hole is formed at at least one position of the edge of the intermediate layer of the optical sheets between the highest layer and the lowest layer, and only the highest layer and the lowest layer of optical sheets are bonded through the hole.

There are other modes in which any damage (such as distortion or warpage) becomes less likely to occur in the laminated sheet construction, and also makes it more difficult for the molten material to protrude out of the laminated sheet construction.

According to the present invention, it is preferable that at least three optical sheets include a lens sheet and a diffusion sheet, and the optical sheets are disposed at the highest and lowest layers. The types of optical sheets constituting the laminated sheet construction are the lens sheet and the diffusion sheet, and placing the diffusion sheets in the highest layer and the lowest layer means that it is possible to protect the lens sheets.

In order to achieve the above object, the present invention provides a method for manufacturing an optical sheet for display comprising a bonding step in which a laminated sheet composition formed by laminating a plurality of optical sheets is bonded at one or more positions of its edges to integrate the composition. Wherein the laminated sheet construction is joined in the bonding step by punching the periphery of the laminated sheet construction into a predetermined punched shape leaving a connection.

According to the present invention, a laminated sheet component formed by laminating a plurality of optical sheets is laminated to a predetermined punched shape in which the laminated sheet component leaves a connection in a bonding step in which the laminated sheet component is bonded at one or more positions of its edges to integrate the component. Joining is performed by punching the periphery of the construct. Thus, a microscopic view of the punched section of the laminated sheet construction resulting from leaving and leaving the connection indicates that the optical sheets on both sides of the punching line constitute a defective structure. This defective structure allows the optical sheets on both sides of the punching line to engage with each spanning different layers. This allows the laminated sheet construction to be coupled with a bonding force that cannot be surpassed by such external forces, such as during processing. Thus, the laminated sheet construction can be integrated by bonding without using a welding method or a consumable article such as an adhesive. This allows the bonded laminated sheet construction to differ in type from among the plurality of optical sheets due to the bonding strength weaker than the external force of the welding or adhesive, even though the molten material may degrade the dimensional accuracy of the laminated sheet construction as in the case of welding. It also does not allow bending caused by the difference in thermal expansion or contraction that results. In this case, punching is not limited to the action from one side of the laminated sheet construction, but may be achieved by a combination of punched shapes resulting from punching in one direction and other shapes resulting from punching in the other direction.

Incidentally, bonding the periphery of the laminated sheet construction is intended to prevent the optical sheet for display from covering any portion of the screen of the liquid crystal display when the laminated sheet construction is fitted to the liquid crystal display device.

According to the invention, the punching is preferably shaped into a C shape or a U shape. This refers to the preferred shape of the punching shape to be C or U. However, the punching shape is not limited to these alone, but may be a partially open rectangular or triangular shape so that the connection portion can be formed. This connecting portion is not limited to one, but may be one or more.

According to the present invention, the pair of punching shapes is preferably formed to face each other. By forming a pair of punching shapes opposite each other in this manner, the optical sheets can be restricted from deviating from each other without having any gaps between them.

According to the invention, it is preferred that the laminated sheet construction is punched out leaving the connection and the connection pressed in the bonding step. By punching out the laminated sheet construction and pressing the connection in this manner, the connection is given a folding pattern, and the bonding force and the integration of the laminated sheet construction are more secure, which can be well resisted to external forces by the processing force. Is done.

According to the invention, the ratio of the length of the connecting portion to the total outer circumferential length of the punching shape is preferably 50% or less. This is because, if the ratio exceeds 50%, the connecting portion becomes too large relative to the outer periphery of the punching shape, allowing easy folding by pressing.

According to the invention, it is preferred that, with the punching of the uncut cut sheet material, punching is achieved with the laminated sheet composition of the product size in a plane size larger than the product size. Punching the uncut laminated sheet construction to product size and simultaneous punching of punching for bonding makes it possible to omit the bonding step and correspondingly contributes to uniaxial processing time.

According to the present invention, punching is preferably achieved to form a punching shape at two or more locations on the periphery of the laminated sheet construction. If the punching shape is formed only in one part of the periphery of the laminated sheet construction, the limiting force on the rotation of the optical sheets relative to each other cannot be sufficiently obtained. Thus, punching shapes may be applied to two or more sides, more preferably on two adjacent sides (placed at an angle of 90 degrees to each other) to achieve sufficient limiting force against the rotation of the optical sheets relative to each other. It is preferable to form.

According to the invention, it is preferred to include folding back a punched portion towards the back side of the laminated sheet construction having a connection as a base end. This is intended to further secure the integration of the laminated sheet construction with the bonding force capable of withstanding such external forces as a force during processing, by folding back the punched-shaped portion towards the rear of the laminated sheet construction having a connection as the base end. .

In order to achieve the above object, the present invention is directed to manufacturing an optical sheet for display provided with a bonding device in which a laminated sheet composition formed by laminating a plurality of optical sheets is bonded at at least one or more positions of its edges to integrate the composition. An apparatus is provided wherein the joining device is a punching press provided with a punching blade for joining, and the notch for punching the construction leaving the connection intact is cut.

This is an apparatus employing the present invention, wherein the joining device is a punching press provided with a punching blade for joining, and the notch for punching the construction while leaving the connection portion is cut. By punching the laminated sheet construction through a punching press provided with a bonding punching blade, the laminated sheet construction can be joined. Incidentally, it is preferable that the edge angle of the joining punching blade is 43 degrees or more.

In addition, in the apparatus according to the invention, the outer peripheral portion of the bonding punching blade is provided with a pressing device for pressing the periphery of the punching position in the laminated sheet construction when the laminated punching material is pulled out after punching the laminated sheet construction. It is preferable. The optical sheets on both sides of the punching line constitute a defective structure, which allows the optical sheets on both sides of the punching line to be engaged while spanning different layers. Thus, when the bonding punching blade is pulled out of the laminated sheet construction, the defect structure may return to the pre-punching state and lose or weaken the bonding force. In view of this problem, a pressing device for pressurizing the periphery of the punching position in the laminated sheet construction when pulling the bonding punching blade for bonding is provided to prevent from returning the defect structure to pre-punching and thus ensuring sufficient bonding force. do.

In the device according to the invention, it is preferred that the joining punching blade is C-shaped or U-shaped, and the pressure bar is preferably arranged inside the C-shaped or U-shaped of the joining punching blade. As mentioned above, the bonding mechanism according to the present invention limits the positional bias of the optical sheets relative to each other by pressing and folding back the punched portions.

In the device according to the invention, the tip of the pressure bar is preferably flushed with the tip of the joining punching blade. Even when the tip of the pressure bar is slightly behind or slightly ahead of the tip of the joining punching blade, the press and folding back effects of the punched parts can be achieved, which means that placing them on the same plane makes this effect more secure. Makes it possible to become

In the device according to the invention, it is preferred that the joining punching blade is arranged with two or more sides of the periphery of the laminated sheet construction over the sides. This is intended to provide a limiting force on the rotation of the optical sheets with respect to each other, as described above.

In the apparatus according to the invention, it is preferred that the uncut sheet laminate is placed in a punching press for punching a planar size whose optical sheet is larger than the article size into a laminate sheet construct of product size. In this configuration, the bonding punching blade is placed in a punching press for punching the uncut cut sheet material into a laminated sheet composition of product size whose optical sheet is larger than the product size, so that the uncut sheet composition is cut. Simultaneous punching, punching to product size and punching for bonding, makes it possible to omit the bonding step, thus contributing to distracting the processing time.

In order to achieve the above object, the present invention provides an integrated optical sheet for display by bonding the composition to at least one position on the periphery of the laminated sheet component formed by laminating a plurality of optical sheets, wherein the laminated sheet component Since the perimeters of the are punched into a predetermined punched shape that leaves a connection in the punched section, the laminated sheet constructions are bonded to each other by engagement of the optical sheets.

The optical sheet for display according to the present invention enables the dimensional accuracy of the laminated sheet construction to be maintained and is freed from bending. In addition, since the optical sheet does not require a welding method or an adhesive, it also contributes to cost reduction.

As described so far, the present invention enables a high quality optical sheet for display to be manufactured through a simpler process at a lower cost.

According to the invention in which three or more optical sheets are laminated and bonded at at least one position of the edge of the laminated sheet construction, the dimensional accuracy of the laminated sheet construction can be maintained, and the resulting optical sheet for display is freed from bending do.

Further, according to the present invention in which a plurality of optical sheets are laminated and bonded at at least one position of the edge of the laminated sheet construction, the dimensional accuracy of the laminated sheet construction can be maintained, and the construction does not use consumables such as adhesives. Can be prevented from bending and consequently contribute to dismiss processing time.

BRIEF DESCRIPTION OF THE DRAWINGS The sectional drawing of the optical sheet for display manufactured by the method of manufacturing the optical sheet for display in 1st Embodiment of this invention is shown.

2 shows a cross-sectional view of an optical sheet for display in another embodiment of the present invention.

3 shows a cross-sectional view of an optical sheet for display in another embodiment of the present invention.

4 is a cross-sectional view of an optical sheet for display in another embodiment of the present invention.

Fig. 5 shows a sectional view of an optical sheet for display in another embodiment of the present invention.

Fig. 6 shows a sectional view of an optical sheet for display in another embodiment of the present invention.

7A and 7B show the junction of an optical sheet for display.

8A and 8B show the junction of an optical sheet for display.

9 shows a configuration of a production line of an optical sheet for display.

10A and 10B show the planar arrangement of the sheet punched out of the laminate.

It is a top view which shows the bonding part of the optical sheet for displays.

12 shows the overall configuration of a device for manually drilling through holes in a second embodiment of the present invention.

13 shows the right profile of the device for drilling through holes.

FIG. 14 shows a partial enlarged view of FIG. 13.

15 shows details of the needle-shaped member.

Fig. 16 shows a perspective view of the positional relationship between the needle-shaped member and the holding plate that is the upper holding member.

17 shows a state where the needle-shaped member penetrates through the optical sheet for display.

18 shows a cross-sectional view of the table.

19 shows the configuration of a production line of optical sheets for display.

20 is a plan view of an optical sheet for display showing a preferred mode of position for forming the through hole.

21 is a plan view of an optical sheet for display showing another preferred mode of position for forming the through hole.

22A, 22B and 22C are plan views of optical sheets for display showing another preferred mode of position for the formation of through holes.

FIG. 23 is a plan view of an optical sheet for display showing another preferred mode of position for formation of through holes; FIG.

24 shows another state in which the needle-shaped member penetrates through the optical sheet for display.

Fig. 25 shows the configuration of a production line for the optical sheet for display in the third embodiment of the present invention.

26A and 26B show a first embodiment of the manufacturing method according to the present invention.

27A and 27B show a second embodiment of the manufacturing method according to the present invention.

28 shows a third embodiment of the manufacturing method according to the present invention.

29 shows a fourth embodiment of the manufacturing method according to the present invention.

30 shows a fifth embodiment of the manufacturing method according to the present invention.

31 shows a sixth embodiment of the manufacturing method according to the present invention.

32 shows a laser irradiation device that is an example of a bonding device.

33 shows an ultrasonic welding device as an example of a bonding device.

FIG. 34 is a conceptual view showing the overall configuration of a manufacturing line for the optical sheet for devices in the fourth embodiment of the present invention. FIG.

35 shows a perspective view of the overall configuration of a production line for an optical sheet for display according to the present invention.

36 shows a punching blade for joining.

FIG. 37 is a diagram illustrating an arrow direction along line A-A in FIG. 36.

FIG. 38 is a diagram illustrating another arrow direction along line A-A in FIG. 36.

FIG. 39 is a diagram illustrating an arrow direction along line B-B in FIG. 36.

40 shows the joining mechanism by the punching operation of the joining punching blade.

41 shows a punching blade for joining in another mode.

42 illustrates a joining punching blade focusing on edge corners.

43A and 43B illustrate punching of laminated sheet construction not cut by the punching blade for bonding.

44A, 44B and 44C show the shape and arrangement of a punching blade for joining.

FIG. 45 illustrates how a plurality of punching shapes are formed on one side of the periphery of the laminated sheet construction by a bonding punching blade.

FIG. 46 illustrates how the punching shape is formed at four corners of the laminated sheet construction by a bonding punching blade.

FIG. 47 illustrates how laminated sheet constructions are punched both front and back by bonding punching blades.

It is a table which shows the composition of the resin liquid used for manufacture of a prism sheet.

The structure of the manufacturing apparatus for prism sheets is shown.

50 is a table showing the results of performance evaluation in the first embodiment of the present invention.

Fig. 51 is a table showing the results of the performance evaluation in the second embodiment of the present invention.

Explanation of the sign

10, 20, 30, 40, 50, 60... Optical sheet for display

10 A, 20 A, 30 A, 40 A, 50 A, 60 A... Junction Unit

12... First diffusion sheet

14. First prism sheet

16. Second prism sheet

18. Second diffusion sheet

72. Impulse sealer

152. Manually drilled through holes

154. table

156. Lifting stage

158. Heater block

162. Arm stand

164. cancer

166. Retaining plate

178. Automatically drills through holes

180... Through hole

217, 219, 221... Punching press

234... gap

236. Molten material

238. Notch

240... gap

244. hall

246. Through hole

419. Pressurized bar

420... Punching Blades for Bonding

421... Notch

427... Connection

448. Punching press

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred form for carrying out the present invention for providing an optical sheet for display and a method and apparatus for manufacturing the same is described below with reference to the accompanying drawings.

(First embodiment for carrying out the present invention)

In view of the first embodiment for carrying out the present invention, first of all, a configuration of an example (first to sixth examples) of an optical sheet for display of the type of laminated sheet composition according to the present invention is described.

1 is a cross-sectional view showing the configuration of an example (Example 1) of an optical sheet for display. The optical sheet for display 10 is a module of an optical sheet constructed by laminating a first diffusion sheet 12, a first prism sheet 14, a second prism sheet 16, and a second diffusion sheet 18 from bottom to top. to be.

Each of the first diffusion sheet 12 and the second diffusion sheet 18 is a sheet having beads fixed with a binder on the surface (one surface) of the transparent film (support), and have a predetermined light diffusion characteristic. The first diffusion sheet 12 and the second diffusion sheet 18 differ not only in bead diameter (average grain size) but also in light diffusing characteristics.

A resin film can be used as the transparent film (support) for the first diffusion sheet 12 and the second diffusion sheet 18. Materials available for the resin film are polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyester, polyolefin, acrylic, polystyrene, polycarbonate, polyamide, PET (polyethylene terephthalate), biaxially stretched These well known materials such as polyethylene terephthalate, polyethylene naphthalate, polyamide imide, polyimide, aromatic polyamide, cellulose acylate, cellulose triacetate, cellulose acetate propionate, cellulose diacetate, are made. Particularly preferred materials among them are polyester, cellulose acylate, acrylic, polycarbonate and polyolefin.

The diameter of the beads with respect to the 1st diffusion sheet 12 and the 2nd diffusion sheet 18 should be 100 micrometers or less, Preferably it is 25 micrometers or less. For example, the average grain size may be 17 μm in a prescribed distribution range of 7 to 38 μm.

The first prism sheet 14 and the second prism sheet 16 are lens sheets in which convex lenses formed in the uniaxial direction are adjacent to each other and disposed substantially over the entire surface, and the pitch, uneven height, and peak angle of the convex portion are Respectively, for example, 50 μm, 25 μm, and 90 degrees (right angles).

The first prism sheet 14 and the second prism sheet 16 are disposed along the axis of the convex lens (prism) in the orthogonal direction. 1, the axes of the convex lenses of the first prism sheet 14 are arranged in a direction perpendicular to the drawing surface, and the axes of the convex lenses of the second prism sheet 16 are parallel to the drawing surface. Is placed. Incidentally, the figure of FIG. 1 is in a different direction from the actual one in order to easily understand that the section of the second prism sheet 16 includes a convex lens.

The material and manufacturing method of the first prism sheet 14 and the second prism sheet 16 may be selected from various known options. For example, one of the available resin sheet manufacturing methods is a transition roller that rotates at a speed substantially the same as the speed at which the resin material is pushed out (with a converted pattern of prism sheet formed on its surface). And the sheet-shaped resin material pushed out of the die between the nip roller plates disposed opposite to the transfer roller and rotating at the same speed, thereby transferring the uneven pattern of the surface of the transfer roller to the resin material.

Other available resin sheet manufacturing methods include a transfer mold plate (stamper) and a resin plate laminated on one surface thereof with another inverted pattern of a prism sheet formed on the surface thereof, and press molding by thermal transfer. To do.

The thermoplastic resin used in such a manufacturing process is, for example, polymethyl methacrylate resin (PMMA), polycarbonate resin, polystyrene resin, MS resin, AS resin, polypropylene resin, polyethylene resin, polyethylene terephthalate resin, poly Vinyl chloride resins (PVC), thermoplastic elastomers, copolymers thereof and cycloolefin polymers.

As another applicable manufacturing method of the resin sheet, the uneven pattern of the surface of the uneven roller (on which the inverted pattern of the prism sheet is formed) is formed by the first diffusion sheet 12 and the second diffusion sheet 18 ( A method of transferring and forming onto the surface of a transparent resin film similar to that used for polyester, cellulose acylate, acrylic, polycarbonate, polyolefin, etc.) may be used.

More specifically, the transparent film formed on at least two layers of the adhesive and the resin (e.g., UV-curable resin) by continuously applying the adhesive and the resin onto the surface is continuously rotated and wound around the swivel roller. The uneven | corrugated sheet manufacturing method which transfers the uneven | corrugated pattern on the surface of an uneven | corrugated roller to a resin layer, and hardens a resin layer (for example by irradiating through an ultraviolet-ray) in the state which a transparent film is wound around an uneven roller can be used. Incidentally, the adhesive may be omitted.

The method of manufacturing the first prism sheet 14 and the second prism sheet 16 is not limited to the above-described example, and is applied only when any other method enables a predetermined uneven pattern to be formed on the surface. It must be stated that it can.

As shown in Fig. 1, at the right end and the left end of the optical sheet 10 for display, the constituent layers are integrated by the bonding portion 10A. Details of the junction 10A are described in detail below.

The optical sheet 10 for a display mentioned above is arrange | positioned between a light source device and a liquid crystal cell, and is used so that it may be comprised with a liquid crystal display element, for example. In this case, the advantage of greatly simplifying the assembling of the liquid crystal display elements as well as the other previously described (manufacturing high quality optical sheets for display at a lower cost in a simpler process than the conventional implementation) can be achieved.

Next, another example (Example 2) of the optical sheet for display according to the present invention is described. 2 shows a section of the configuration of the optical sheet for display 20. Incidentally, the same or similar members as the counterparts in Fig. 1 (Embodiment 1) are designated by the same reference numerals, and the detailed description thereof is omitted.

The optical sheet 20 for a display is an optical sheet comprised by laminating | stacking in order from the diffuser sheet 12, the 1st prism sheet 14, and the 2nd prism sheet 16 from below. Unlike the above-described optical sheet 10 for display, the second diffusion sheet 18 is omitted where extensive diffusion performance is not required.

Similar to the first example, the above-described display optical sheet 20 is disposed between the light source device and the liquid crystal cell, and is used to be configured with, for example, a liquid crystal display element.

Next, another example (Example 3) of the optical sheet for display according to the present invention is described. 3 shows a section of the configuration of the optical sheet for display 30. In Fig. 1 (Embodiment 1) and Fig. 2 (Embodiment 2), the same or similar members as their counterparts are designated by the same reference numerals, and the detailed description thereof is omitted.

The optical sheet for display 30 is an optical sheet configured by laminating in order from the bottom to the top of the first diffusion sheet 12, the prism sheet 14, and the second diffusion sheet 18.

In the optical sheet for display 30, unlike the optical sheet 10 for display described above, the second prism sheet 16 is omitted where diffusion performance is not required in the direction perpendicular to the drawing surface.

Similar to the first example, the above-described display optical sheet 30 is disposed between the light source device and the liquid crystal cell, and is used to be configured together with, for example, a liquid crystal display element.

Next, another example (Example 4) of the optical sheet for display according to the present invention is described. 4 shows a section of the configuration of the optical sheet for display 40. The same or similar members as those in FIGS. 1 (Example 1) and 2 (Example 2) are designated by the same reference numerals, and detailed description thereof is omitted.

The optical sheet 40 for a display is an optical sheet comprised by laminating | stacking in order from the diffusion sheet 12 and the prism sheet 14 from below. Unlike the above-described optical sheet for display 10, where a wide range of diffusion performance is not required, the second diffusion sheet 18 is omitted, and unlike the optical sheet 10 for display, diffuses in a direction perpendicular to the drawing surface. Where performance is not required, the second prism sheet 16 is omitted.

Similar to the first example, the above-described display optical sheet 40 is disposed between the light source device and the liquid crystal cell, and is used to be configured together with, for example, a liquid crystal display element.

Next, another example (Example 5) of the optical sheet for display according to the present invention is described. 5 shows a section of the configuration of the optical sheet for display 50. The same or similar members as those in FIGS. 1 (Example 1) and 2 (Example 2) are designated by the same reference numerals, and detailed description thereof is omitted.

The optical sheet 50 for a display is an optical sheet comprised by laminating | stacking the order of the 1st prism sheet 14, the 2nd prism sheet 16, and the diffusion sheet 18 from the bottom. Unlike the above-described optical sheet 10 for display, the first diffusion sheet 12 is omitted where extensive diffusion performance is not required.

Similarly to the first example, the above-described display optical sheet 50 is disposed between the light source device and the liquid crystal cell, and is used to be configured with, for example, a liquid crystal display element.

Next, another example (Example 6) of the optical sheet for display according to the present invention is described. 6 shows a section of the configuration of the optical sheet for display 60. The same or similar members as those in FIGS. 1 (Example 1) and 2 (Example 2) are designated by the same reference numerals, and detailed description thereof is omitted.

The optical sheet for display 60 is an optical sheet comprised by laminating | stacking in order of the 1st prism sheet 14 and the diffusion sheet 18 from below. Where extensive diffusion performance is not required unlike the optical sheet for display 10 described above, the first diffusion sheet 12 is omitted and diffuses in a direction perpendicular to the drawing surface unlike in the optical sheet for display 10. Where performance is not required, the second prism sheet 16 is omitted.

Similar to the first example, the above-described display optical sheet 60 is disposed between the light source device and the liquid crystal cell, and is used to be configured with, for example, a liquid crystal display element.

There is no particular limitation on the planar dimensions of the optical sheets for displays 10 to 60 described so far, but these dimensions can match the size of the backlight unit of various types of displays (such as liquid crystal display elements) used and The range is, for example, 127 mm (5 inches) to 1640 mm (65 inches) in diagonal length.

Next, the junction part 10A (20A, 30A, 40A, 50A, and 60A) which comprises the characteristic aspect of this invention is demonstrated in detail. 7A and 7B show the bonding portion 30A of the optical sheet 30 for display (third example in FIG. 3). FIG. 7A is a top view and FIG. 7B is a right side profile of FIG. 7A.

In the optical sheet for display 30, the bonding portion 30A is formed on only one longer side by the heat-adhesive film 80. More specifically, as shown in FIG. 7B, the heat-adhesive film 80 is the same between the first diffusion sheet 12 and the prism sheet 14 and between the prism sheet 14 and the second diffusion sheet 18. The width W is arranged along the periphery.

It is preferable that the width W of the heat-adhesive film 80 becomes 2-4 mm (within the range of 2-4 mm from an edge). When the width is maintained within this range, the heat-adhesive film 80 hardly affects the viewing range of the display device, and at the same time, can secure sufficient adhesive force.

Incidentally, while the right end of the heat adhesive film 80 and the right end of the display optical sheet 30 are on the same plane in the example shown in FIG. 7B, the right end of the heat adhesive film 80 is the optical for display. It may be located much inward than the right end of the sheet 30.

Instead of the configuration in which the bond 30A is formed by the heat-adhesive film 80 only on the longer side as shown in FIGS. 7A and 7B, two or more sides (two opposite sides or two, three or four adjacent It is also possible to form the junction 30A in the side surface).

It is also possible to form the joining portion 30A intermittently instead of forming the joining portion 30A that is continuous over the entire length of the side surface.

It is preferable that the thickness of the heat-adhesive film 80 after adhesion is 0.1 mm or less. This thickness serves to facilitate uniformity of gaps between the optical sheets and to reduce the risk of occurrence of interference fringes.

Heat-adhesive film 80, a film of the type known as "hot melt", is used to bond members together by heating (and pressing). Since this heat-adhesive film 80 has the characteristics 1) to 6) described below, this film can be suitably used for the optical sheet for display according to the present invention.

1) The thin composition contributes to making the adhesive layer uniform (particularly to the uniformity of thickness).

2) can be cut into any desired shape that does not allow the adhesive layer to protrude outward.

3) Unlike any conventional type of adhesive, no viscosity control is necessary. And no step for drying the solvent or the skilled person is required.

4) There are various options for the method of adhesion, which include high frequency heating, ultrasonic heating and thermal pressurization, which easily provide strong adhesion.

5) Since it is a hot melt type and does not use any solvents, it is superior in terms of stability (since it does not emit contaminated odors and does not have flammability so as not to adversely affect human health).

6) The film does not change quality and does not cure over time.

Usable examples of such thermal adhesive films 80 are, for example, Nihon Matai Co., Ltd. It includes the heat-adhesive film manufactured by (Product Name: Elphan). Products available for this purpose include Elphan NT (polyamide), Elphan UH (polyurethane), Elphan PH (polyester) and Elphan OH (EVA), with Elphan PH (polyester) being particularly preferred.

Applicable methods (apparatus) for adhering the heat-adhesive film 80 all include the high frequency heating (high frequency sealing apparatus), the ultrasonic heating (ultrasound sealing apparatus), and the heat pressurization (heater heating apparatus) described above.

For example, heating devices available for thermal pressurization include an impulse sealer (eg, manufactured by Fuji Inpulse Co., Ltd.). The preferred adhesion temperature (heating temperature) of the thermal adhesive film 80 is 110 to 230 ° C., although the optimum temperature varies depending on the film material and other factors.

Since the above-described optical sheet for display 30 uses the heat-adhesive film 80 having numerous features described above, this optical sheet is caused by mismatching between a plurality of films resulting from thermal expansion or contraction (distortion). Or damage) (such as warping). Thus, there is no need to increase the thickness of the individual film (increasing the firmness) or take some other measures to correct such damage, resulting in reduced design constraints and cost savings.

Next, the junction parts 10A (20A, 30A, 40A, 50A and 60A) are described. 8A and 8B show the bonding portion 30A of the optical sheet 30 for display (third example in FIG. 3). 8A shows a perspective view and FIG. 8B shows a right side profile of FIG. 8A.

In the optical sheet for display 30, the bonding portion 30A is formed on only one longer side by the heat-adhesive film 80. More specifically, as shown in FIG. 8B, a heat-adhesive film 80 is attached to the right peripheral side of the first diffusion sheet 12, the prism sheet 14, and the second diffusion sheet 18, and this sheet Are bonded to each other by this heat-adhesive film 80.

Instead of being formed on only one longer side by the heat-adhesive film 80 as shown in FIGS. 8A and 8B, two or more sides (two opposite sides or two, three or four) It is possible to form the junction 30A on two adjacent sides).

It is also possible to form the junction 30A intermittently instead of forming the junction 30A continuous over the entire length of one side.

The same material as the material used for the configuration shown in FIGS. 7A and 7B can be used for the heat-adhesive film 80. Applicable methods (apparatus) for adhering the heat-adhesive film 80 all include the above-described high frequency heating (high frequency sealing apparatus), ultrasonic heating (ultrasound sealing apparatus), and heat pressurization (heater heating apparatus).

In particular, since the heat-adhesive film 80 is attached to the peripheral side of the optical sheet for display 30 in the mode shown in FIGS. 8A and 8B, a thread-less biding machine or a spine- Apparatus of a configuration similar to the apparatus for bookbinding, known as a spin-pasting machine, may be preferably used.

In the mode shown in FIGS. 8A and 8B, unlike the previously described configuration shown in FIGS. 7A and 7B, since the heat-adhesive film 80 is exposed even after completion of the optical sheet 30 for display, if necessary, The thermal adhesive film 80 can be easily removed.

In the mode shown in FIGS. 8A and 8B, it is possible to stack optical sheets in advance with respect to the plurality of display optical sheets 30, and the heat-adhesive film 80 of the plurality of display optical sheets 30 can be laminated. It is possible to cut and heat bond the adhesive film 80 to each peripheral side, and then to separate from each of the optical sheets for display.

The optical sheet 30 for display described with reference to FIGS. 8A and 8B can provide excellent effects substantially similar to previous versions of the optical sheet 30 for display described with reference to FIGS. 7A and 7B.

Next, a method of manufacturing the optical sheet for display is described. Although the manufacturing method can be commonly applied to all of the display optical sheets 10 to 60 described so far, for convenience of description, the following description is applied to the four-layer optical sheet for display (Example 1) See the case of the method.

9 shows a configuration of a production line 11 for an optical sheet for display. The roller in which the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16 and the second diffusion sheet 18 already described with reference to FIG. 1 is disposed at the left end of FIG. 12B, 14B, 16B and 18B).

The rollers 12B, 14B, 16B and 18B are rotated on the rotating shaft of the supply means (not shown), and the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16 and the second The diffusion sheet 18 can be supplied from the outside of the rollers 12B, 14B, 16B and 18B, respectively, at substantially the same speed.

The first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16 and the second diffusion sheet 18 to be supplied are supported by the guide rollers G, G ..., respectively, Finally laminating from the punching press 48 to the upper position (lamination step) is described below. Punching presses 48 are used to trim the edges of the laminated sheet construction to product size.

In the production line 11 of the optical sheet for display, the film feeders 52, 54 and 56 are disposed below from the rollers 12B, 14B, 16B and 18B. The film feeders 52, 54 and 56 feed the heat-adhesive film 80 from their respective ends.

The film feeder 52 supplies the heat-adhesive film 80 to the surface of the first diffusion sheet 12 to bond the first diffusion sheet 12 and the first prism sheet 14 to each other; The film feeder 54 supplies the heat-adhesive film 80 to the surface of the first prism sheet 14 to adhere the first prism sheet 14 and the second prism sheet 16 to each other; The film feeder 56 supplies the heat-adhesive film 80 to the surface of the second prism sheet 16 to adhere the second prism sheet 16 and the second diffusion sheet 18 to each other.

The constituents of the laminated sheets to which the heat-adhesive film 80 was supplied at appropriate positions, respectively, are transferred to the impulse sealer 72 heated and pressurized on the peripheral side and bonded with the heat-adhesive film 80.

The bonding composition of the laminated sheet is transferred to the punching press 48 and the edges are trimmed to fit the product size.

Through these steps, an optical sheet 10 for display (see FIG. 1) is formed. The optical sheet 10 for display is conveyed on the conveyor 26 and stopped there. The display optical sheet 10 on the conveyor 26 is successively laminated onto the stacker 32 by the suction passing device 28.

On the other hand, the laminated sheet constitution 34 in which the optical sheet for display 10 is punched by the punching press 48 is wound around the take-up roller 36 of a take-up device (not shown in detail). do.

The method of manufacturing the above-mentioned display optical sheet provides the effects of the following 1) to 3).

1) Stripe defect reduction effect

Any streaks on the upper or lower surface of the lens sheet (first prism sheet 14 or second prism sheet 16) become more noticeable by the lens effect of the sheet. On the other hand, any streaks on the lower surface on the diffusion sheet (first diffusion sheet 12 or second diffusion sheet 18) become less noticeable by light diffusion. For this reason, preventing streaks on the lens sheet contributes to reducing streak defects. Since streaks often occur when processing the sheet after processing, the combination of the diffusion sheet and the lens sheet enables the diffusion sheet to act as a protective sheet, whereby the stripe defect can be reduced. This effect is particularly important for the optical sheet for display 10 of the first example (see FIG. 1) and the optical sheet for display 30 of the third example (see FIG. 3) in which no lens sheet is exposed on the surface. Do.

2) reduction of assembling man-hour

For example, where the optical sheet for display 10 of the first example (see FIG. 1) is used for assembling a liquid crystal display element, the amount of labor consumed at the time of assembling unites the optical sheet for display 10. The same amount of labor as the step of letting, but where a conventional sheet is used, including the integration of the first diffusion sheet, removing the protective sheet on the back of the first lens sheet, and protecting the sheet on the front of the first lens sheet. Remove the first lens sheet, remove the protective sheet on the rear surface of the second lens sheet, remove the protective sheet on the front surface of the second lens sheet, integrate the second lens sheet and the second diffusion sheet. Eight steps to integrate In this way, a significant reduction in the labor load in which the assembling process is carried out can be reduced due to the first manufacturing method, resulting in a significant reduction in human-labor power and corresponding cost savings.

3) protective sheet reducing effect

In this case, a protective sheet is attached to both sides of the lens sheet to prevent streaks. The above-mentioned protective sheet is damaged after the lens sheet is integrated, thus showing considerable waste. The present invention can be omitted with such a protective sheet by using a diffusion sheet as the protective sheet.

More specifically, one protective sheet is each provided with one protective sheet in the optical sheet 40 for display of the fourth example (see FIG. 4) and the optical sheet 60 for display of the sixth example (see FIG. 6). Omitted; Two protective sheets are omitted in the optical sheet for display 30 of the third example (see FIG. 3); Three protective sheets each are omitted in the optical sheet for display 20 of the second example (see FIG. 2) and the optical sheet for display 50 of the fifth example (see FIG. 5); In the optical sheet 10 for display of the first example (see FIG. 1), four protective sheets may be omitted, respectively.

Next, punching is performed from a laminate (optical sheet 10 for display) including the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16, and the second diffusion sheet 18. The planar arrangement of the drawn sheets is described.

10A and 10B show the planar arrangement of the sheets punched out of the laminate (optical sheet 10 for display).

FIG. 10A shows a state in which the sheets are cut in parallel and orthogonal directions with respect to the direction in which the laminate is conveyed, and FIG. 10B shows a state in which the sheets are cut in an oblique direction with respect to the direction in which the laminate is conveyed.

As explained so far, high quality optical sheets for displays can be produced at a lower cost in a simpler process according to the invention than by the prior art.

The present invention also provides the following effects.

1) Cost savings and increased product value to reduced thickness

Optical sheets used in large liquid crystal TV sets that must be rigid have a support about twice the thickness of conventional optical sheets. However, the optical sheet according to the present invention can be sufficiently hard without thickening the constituent sheets due to its constituent structure, and furthermore, allows the individual layers to be slightly thinner.

2) preventing performance improvement or condensing effect

Several products are matted on the back side to prevent damage to the lens sheet (to make the streaks less visible). The optical sheet according to the present invention does not require any treatment that not only reduces the manufacturing cost but also prevents the improvement of the performance due to matting or the prevention of the light collection effect.

In the present embodiment, an example of the optical sheet for display according to the present invention has been described so far, but the present invention is not limited to these examples and can be performed in various other modes.

For example, in all the examples of the foregoing examples, the prisms of the first prism sheet 14 and the second prism sheet 16 face upwards, but the sheets may be stacked with prisms oriented so as to face downwards. .

Although the laminated structure of the optical sheet for display is not limited only to the above-mentioned example, For example, protective sheets can be laminated | stacked on the upper surface and the lower surface. This configuration functions in the same way and provides the same effect as in any of the above-described embodiments.

(2nd Embodiment for Carrying Out the Invention)

A second embodiment for carrying out the present invention is described below with reference to the accompanying drawings. Incidentally, the configuration of the examples (first to sixth examples) of the optical sheet for display of the laminated sheet composition type is the same as in the first embodiment described with reference to Figs. Explanation is made using corresponding symbols.

Details of the joints 10A (20A, 30A, 40A, 50A and 60A) constituting the features of the second embodiment are described. FIG. 11 is a plane showing the bonding portion 30A of the optical sheet for display 30 (third example shown in FIG. 3). In the optical sheet for display 30, the bonding portion 30A is formed only on one long side (upper side) by the plurality of through holes 180, 180,...

Incidentally, although there are preferred positions for the plurality of through holes 180, 180, ... formed as described below with reference to Figs. 20-23, this description provides a simple hole arrangement for ease of explanation. Indicates.

The distance D between the edge of the optical sheet 30 for display and the innermost edge of the sheet of the through hole 180 is 5 mm or less, more preferably D is 3 mm or less. The formation of the through hole 180 in this position allows the field of view of the display to substantially prevent negative effects and ensure sufficient adhesion.

The optimum pitch P of the through holes 180, 180, ... changes the size and configuration of the optical sheet 30 for display (optical sheet 10, 20, 40, 50 or 60 for display). Where the pitch P is too small, wave damage of the sheet causing the interference fringe is likely to occur, and accordingly, it is preferable that the pitch P be 10 mm or more in a linear arrangement as shown in FIG. On the other hand, because there is no upper limit for the pitch P, too large pitch may negatively affect the engagement state between the optical sheets.

Incidentally, the junction 30A is formed on two or more sides (two opposite sides or two, three or four adjacent sides) instead of being formed only on one longer side as the configuration shown in FIG. 11. It is also possible to form a.

Next, a device (apparatus) for forming the through holes 180, 180, ... will be described. Incidentally, since the manufacturing line 111 of the optical sheet for display described below with reference to FIG. 19 uses an automated through hole device 178, a simple manual apparatus is described for the sake of understanding.

FIG. 12 shows the overall configuration of the device 152 for manually punching through holes, FIG. 13 shows its right profile, and FIG. 14 shows a partial enlarged view of FIG. The apparatus comprises a table 154 holding the display optical sheet 30 (10, 20, 40, 50, 60), and an elevating stage for elevating a plurality of needle-shaped members (N, N, ...). 156, and a heater block 158 (see FIGS. 13 and 14), which is a device for heating the needle-shaped members N, N, ..., are provided and heated at a plurality of positions on the edge of the optical sheet stack. Through holes 180, 180,... Can be formed by the needle-shaped members N, N,...

The table 154 fixed over the substrate B of the apparatus has a flat surface (upper surface). The discharge hole 154A is formed near the left edge of the table, and the sheet stopper 154B is formed near the right edge. Details of the discharge hole 154A and the seat stopper 154B are described below.

As shown in FIG. 13, the lifting stage 156 of the stage 156B supported by the struts 156A and 156A and the struts 156A and 156A standing up against the right side and the left side of the substrate B is elevated. It is configured to. Incidentally, the stage 156B is lifted up by a spring device (not shown), and as shown by Fig. 16, the tip of the needle-like member N, N, ... is used for display. It is an upper position which is not in contact with the optical sheet 30.

As shown in FIG. 13, the heater block 158 is fixed to the stage 156B, and the needle-shaped members N, N, ... are heated at a predetermined pitch P as shown in FIGS. 13 and 14. Is fixed to block 158.

An electric heater (not shown) is embedded in the heater block 158, and electric power is supplied from the heater controller 158A shown in FIG. 12 to the electric heater via the power supply cable 158B.

Referring to FIG. 12, the arm stand 162 is erected near the left end of the substrate B, and one end (left end) of each of the arms 164 and 164 is provided in the upper portion of the arm stand 162. and rotatably held by fulcrum 162A.

Arm handle 164A is fixed to the other end (right end) of arms 164 and 164, and at two ends arm 164 and 164 rotate relative to arm handle 164A.

The portions facing these arms 164, 164 are engaged with the top of the stage 156B. By pressing the arm handle 164A down in the direction of the arrow 164B in FIG. 12, the stage 156B is moved downward, and the tips of the needle-shaped members N, N, ... are displayed. It can be moved to a position that can penetrate the optical sheet 30 for.

Since the front and right profiles of the needle-shaped members of FIG. 14 appear to ensure good thermal conductivity from the heater block 158, the needle-shaped members N, N,... Are fixed to the heater block 158. The pitch P of the needle-like members N, N, ... has already been described above with reference to FIG. The zone Z in which the needle-shaped members N, N, ... are disposed can be appropriately determined in relation to the width of the optical sheet 30 for display through which the needle-shaped members penetrate.

15 shows details of the needle-shaped member N; Fig. 16 shows a perspective view of the positional relationship between the needle-shaped members N, N,... And the holding plate 166 which is the upper holding member, and FIG. 17 shows that the needle-shaped member N is an optical sheet for display. 30 shows a state penetrating. Referring to Fig. 16, the release groove 154G cuts instead of the release hole 154A in the table 154 (corresponding to the lower holding member). This release groove 154G provides an effect similar to the release hole 154A.

Since there is no restriction | limiting in particular about the material of the needle-shaped member N, copper which is excellent in thermal conductivity is preferable, and bronze after copper which is also excellent in thermal conductivity is preferable next to copper. Incidentally, a commercially available solder iron tip can be used as the needle-like member N.

The shape of the needle-shaped member N is not particularly limited, but is also shown in FIG. 15 having a relatively small diameter tip N1 penetrating the optical sheet 30 for display and a base end N2 larger than the tip N1. A two-step configuration as shown is preferred in terms of strength and heat conduction. As shown in FIG. 15, the length of the tip N1 and the base end N2 may be 10 mm and 40 mm, respectively.

Since the conical tip can easily penetrate the optical sheet for display 30, it is preferable to form the conical tip N1 end. There is no particular limitation on the diameter of the tip N1, but if this diameter is too small as in the example described below (see the table in FIG. 51), the melt volume of the resin becomes insufficient, which provides an appropriate coupling effect. Not all of them are desirable because too large a diameter causes the molten portion of the resin to intervene in the image display area of the optical sheet for display 30. Therefore, the diameter of the tip N1 is preferably in the range of 0.3 to 2.0 mm.

When the diameter of the tip N1 is relatively small (for example, 0.3 mm), forming the end of the straight tip N1 instead of the cone does not cause a significant difference in terms of effect.

As shown in FIG. 16 and FIG. 17, an insertion hole 166B is formed in the holding plate 166 to allow the tip N1 of the needle-shaped member N to penetrate. As shown in Fig. 17, the interference between the needle-shaped member N and the table 154 is prevented by the discharge hole 154A (emission groove 154G) formed in the table 154 already described. Referring to Fig. 17, in the state where the needle-like member N penetrates through the optical sheet for display, the bottommost portion is prevented by a stopper (not shown). Incidentally, the code D in Fig. 17 is the same as the distance D in Fig. 11.

The configuration shown in FIG. 17 causes the retaining plate 166 (corresponding to the upper retaining member) and the table 154 (corresponding to the lower retaining member) to squeeze the edges of the needle-shaped member N having no gaps. This makes it difficult for the molten portion of the optical sheet for display 30 to enter between the optical sheets and cause distortion or interference fringes of the sheet composition.

It is preferable that the hole 166D of the insertion hole 166B and / or the hole 154D of the discharge hole 154A (width of the discharge groove 154G) be 1.02 to 4 times the diameter of the needle-shaped member N. . This hole hole 166D and / or groove width 154D makes it possible to press the edge of the needle-shaped member N without any gap. The hole hole 166D and / or groove width 154D is preferably 1.5 to 3 times the diameter of the needle-shaped member N, and preferably 1.8 to 2.5 times the diameter of the needle-shaped member N.

The compressive force acting on the holding plate 166 and the table 154 is preferably 0.2 Pa to 6.0 Pa. This pressing force can enable the needle-shaped member N to be pressed without any gap and can prevent it from damaging the surface pattern of the optical sheet. The compressive force is preferably 0.4 Pa to 4.0 Pa, more preferably 0.6 Pa to 3.0 Pa.

12 and 13, retaining plate arms 166A and 166A provided at the lower end with retaining plate 166 are arranged to engage around the central portion of arms 164 and 164. As described above, the holding plate 166 restricts the movement of the display optical sheet when the needle-shaped member N penetrates the display optical sheet 30 by pressing the display optical sheet 30. It is a member to do. Retaining plate arms 166A and 166A are engaged with arms 164 and 164 and are arranged to move up and down by rotation of arms 164 and 164.

Next, the details of the seat stopper 154B are described. 18 shows a section of the table 154. The sheet stopper 154B is a member for limiting the movement of the optical sheet 30 for display. By pressing the right end 30R of the display optical sheet 30 against the left end of the sheet stopper 154B, the position of the left end 30L of the display optical sheet 30 is limited.

The seat stopper 154B is an elongate member whose section is L-shaped (angle member). By inserting the bolt member 168 into the through hole (not shown) and screwing the bolt member 168 into the tapped hole 154C of the table 154, the seat stopper 154B is moved to the table ( 154).

Incidentally, as shown in Fig. 18, a plurality of tapped holes 154C, 154C, ... are formed in the table 154 so that the table 154 is suitable for the optical sheet for display 30 of different sizes. Let's do it.

Next, a method of allowing the optical sheets to be engaged with each other by using the above-described penetrating device 152 is mainly described with reference to FIG.

Before engaging them, the seat stopper 154B is set to an appropriate position. In addition, the heater block 158 is set to an appropriate temperature through the heater controller 158A. This temperature, which varies with the material of the optical sheet, should be lower than the melting point of PET (253-258 ° C.) when the support of the optical sheets is polyethylene terephthalate (PET). However, if the temperature is relatively lower than this melting point, this temperature is 265 because of the problem (thickness problem) that the molten material tends to remain as a remnant between the support of the optical sheet and the needle-shaped member N. It is preferable that it is more than degreeC.

If the set temperature is too high, the entire device must be made robust enough to maintain that high temperature. However, by forming a locally heated structure such as solder to maintain a high temperature up to 480 ° C., the entire device does not need to be robust enough to maintain a high temperature, and thus can be manufactured at low cost. In addition, when the set temperature is too high, the support PET becomes stronger without causing a quality problem that obstructs the shape of the through hole 180. Therefore, it is preferable that the set temperature of the heater block 158 becomes 300 degrees C or less.

In the engagement procedure, the optical sheet 30 for display is first set on the table 154. In this step, the display optical sheet 30 is positioned by pressing its right end 30R to the left end portion of the sheet stopper 154B (see Fig. 18).

Thereafter, the arm handle 164A is pressed downward in the direction of the arrow 164B of FIG. 12. This causes the retaining plate 166 to press the display optical sheet 30 to limit the movement of the display optical sheet 30. Thereafter, the stage 156B moves the tip of the needle-shaped members N, N, ... down to penetrate the optical sheet 30 for display and stops at the position shown in FIG. In this state, the optical sheet around the edge of the needle-shaped member N is melted.

Next, the arm handle 164A is pushed upward in the direction opposite to the direction of the arrow 164B in FIG. 12. This causes the tips of the needle-shaped members N, N, ... to first fall out of the optical sheet for display 30, and then the retaining plate 166 releases the pressure on the optical sheet for display 30. do.

In this state, the molten portion of the optical sheet is solidified. In this process, the upper and lower optical sheets are bonded to each other by the solidified molten portion so that the plurality of optical sheets are integrated with each other.

Since the through holes 180 are formed at one or more positions on the edges of the laminated sheet construction, the through holes 180 are formed by the aforementioned method of hitting the optical sheets with each other by using a device for penetrating the through holes 152. ) The optical sheets are engaged with each other, and the step of cutting numerous films (sheets) into product size can be omitted, thus laminating a plurality of layers of film (sheets) while positioning them. Can be. It is also free from the above-mentioned problems derived from the protective sheet, which has advantages in both cost and quality. In addition, it is free from the above-described problem that occurs when a plurality of layers of the film are laminated.

In addition, since the mismatch between the plurality of films due to thermal expansion or contraction is alleviated by the engagement of the through holes 180 formed at intervals, there is little damage (such as distortion or warpage) due to mismatching. Do not. Thus, the thickness of the individual film is increased (improved stiffness) or it is not necessary to take some other measures to correct such damage, as a result, design constraints are reduced and cost savings result.

For the reasons described so far, high quality laminated sheet constructions for displays such as liquid crystal display elements and the like can be produced at a lower cost in a simpler process according to the present invention as compared to the prior art.

Next, a method of manufacturing an optical sheet for display in which the engaging entanglements of the optical sheets with respect to each other are used in an automated mode by using a device for drilling through holes is described. Although this manufacturing method is commonly applicable to all of the above-described display optical sheets 10 to 60, for convenience of explanation, this method is applied to the four-layer optical sheet for display (Example 1). In case of application.

19 shows the configuration of a production line 111 of an optical sheet for display. The rollers 112B, 114B, 116B and 118B shown toward the left end of the drawing are the first diffusion sheet 12, the first prism sheet 14, the second prism already described in the first embodiment of FIG. 1. The sheet 16 and the second diffusion sheet 18 are rollers wound individually.

The rollers 112B, 114B, 116B and 118B are rotated on a rotating shaft of a feeding device (not shown), and the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16, and the first The two diffusion sheets 18 can be supplied from the rollers 112B, 114B, 116B and 118B, respectively, at substantially the same speed.

The first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16 and the second diffusion sheet 18 supplied are supported by respective guide rollers G, G, ... And the other one is finally laminated on the upper side in the device 178 for drilling the through hole (lamination step). Punching presses 148 are used down from the device 178 for drilling through holes to trim the edges of the stack to suit the product size.

The automated through hole drilling device 178 operating on the same principle as the manually described through hole drilling device 152 described above is automatically spit through the cylinder device instead of manually through the arm handle 164A. The shape members N, N, ... are moved up and down. An orthogonal robot or the like used for positioning any display optical sheets 10 to 60 and for another purpose is provided.

The through hole 180 is formed by the device 178 that penetrates the through hole, and the laminated sheet composition including the optical sheets engaged with each other by the through hole 180 is delivered to the punching press 148 to the product size. Edge trimming is performed accordingly.

By performing the above-described process, the optical sheet for display 10 (see FIG. 1) is formed. The display optical sheet 10 is conveyed on the conveyor 126 and stops there. Optical sheets 10 for display on the conveyor 126 are successively stacked on the stacker 132 by the suction passing device 128.

On the other hand, the laminated sheet constitution 134 in which the optical sheet for display 10 is punched by the punching press 148 is wound around the winding roller 136 of the winding apparatus (not shown in detail).

The method for manufacturing the optical sheet for display described above (including the manual manufacturing method described above) can achieve 1) stripe defect reduction effect, 2) assembling human-labor reduction effect, and 3) protective sheet reduction effect. And detailed explanations of these effects are omitted because they are similar to the effects of the first embodiment. Further, the sheet (the optical sheet for display 10) punched out of the laminate of the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16, and the second diffusion sheet 18. The planar arrangement is similar to the arrangement of the first embodiment described with reference to FIGS. 10A and 10B.

Next, preferred positions for the formation of the through holes 180, 180, ... are described with reference to Figs. Although the embodiment shown in FIG. 11 can achieve the effects of the invention as described above, it is more preferable by placing at least two per cm 2 of through holes 180, 180,... At the mutually engaging portions. The result can be obtained. 4 / cm <2> is more preferable and, as for the density of the through-holes 180, 180, ..., 6 / cm <2> is more preferable.

20 is a plan view of the optical sheet for display 10. The optical sheet 10 for display is 813 mm (32 inches) in diagonal length, and has a tab 10T, one at the center of each of the four sides as a catch. Through holes 180, 180, ... are formed in tabs 10T on two short sides.

Through holes 180, 180,... Are provided in the upper and lower two rows at a density of 6.25 / cm 2. By arranging the through holes 180, 180, ... in the catch (tab 10T) in this manner, the effect of the present invention is more markedly achieved where the mutual engagement of the optical sheets is more acceptable. Can be.

21 is a plan view of the optical sheet for display 10. The optical sheet for display 10 is 1143 mm (45 inches) diagonally, and has a plurality of notches on all its long sides. Through holes 180, 180, ... are formed in two short sides.

The upper and lower two rows are provided where the through holes 180, 180,... Are of a density of 6.25 / cm 2. By arranging the short-sided through holes 180, 180,... Which can act as catches in this way, where the mutual engagement of the optical sheets is more acceptable, the effect of the invention can be achieved more remarkably. Can be.

22A is a plan view of another display optical sheet 10. The optical sheet for display 10 is 660 mm (26 inches) to 813 mm (32 inches) in diagonal length, and has tabs 10T, one in the center of each of the four sides. Through holes 180, 180,... Are formed in tabs 10T on each side surface. 22B and 22C show enlarged views around the tab 10T on the left short side surface.

The through holes 180, 180, ... are formed at two positions of each tab 10T, and are arranged at a density of 8 / cm 2 in five spot patterns on the die top of FIG. 22B. FIG. 22C is disposed at a density of 4 / cm 2 in four spot patterns on top of the die of FIG. 22B. By arranging the through holes 180, 180, ... in this manner in the catch (tab 10T), the effect of the invention can be achieved more remarkably where the mutual engagement of the optical sheets is more acceptable. Can be.

23 is a plan view of another optical sheet for display 10. The optical sheet for display 10 is 1143 mm (45 inches) diagonally in length, and has a plurality of notches on all of its long sides. Through holes 180, 180,... Are formed in tab 10T on each side.

Through holes 180, 180,... Are provided in two positions on the short side and three on the long side. They are arranged in a pattern of five spots on the die at a density of 12.5 / cm 2. By arranging the through holes 180, 180,... In this way on the side that can act as a catch, the effect of the invention can be more significantly achieved where the mutual engagement of the optical sheets is more acceptable. have.

As described so far, high quality optical sheets for displays can be manufactured at a lower cost in a simpler process in accordance with the present invention than in the prior art.

According to the present invention, as described with reference to the first embodiment, 1) cost reduction and product value enhancement or reduction of thickness and 2) performance improvement and prevention of deterioration of the light collection effect can be achieved. The details are similar to the details of the first embodiment.

Although an example of the optical sheet for display according to the present invention of this embodiment has been described so far, the present invention is not limited to these examples, and can be carried out through various other ways.

For example, although the positional relationship between the needle-shaped members N, N,... And the retaining plate 166 is assumed to be as shown in FIG. 17, this relationship may be some other configuration. 24 shows a configuration of another example corresponding to FIG. 17. In this configuration, the top plate 166I is fixed to the base end N2 of the needle-shaped member N, and the retaining plate 166 is held by the top plate 166I through the spring members 166H and 166H. .

In this configuration, the holding plate 166 presses the display optical sheet 30 through the spring members 166H and 166H along the lower portion of the needle-shaped member N. As shown in FIG. Thus, the retaining plate arms 166A and 166A shown in FIG. 12 and the like are not required.

In all examples of the above-described second embodiment, the prisms of the first prism sheet 14 and the second prism sheet 16 are assumed to face upwards, but these sheets may be laminated with prisms oriented downward. have.

Although the laminated structure of the optical sheet for display is not limited to the above-mentioned example, a protective sheet can be laminated | stacked over the upper and lower surfaces, for example.

This configuration functions in the same manner and provides the same effects as in the second embodiment.

(Third embodiment for carrying out the present invention)

A third embodiment for carrying out the present invention is described below with reference to the accompanying drawings. Incidentally, the configuration of the example (first to sixth example) of the optical sheet for display of the stacked sheet composition type is the same as that of the first embodiment described with reference to Figs. 1 to 6, by using the same corresponding reference numerals. It is explained.

A manufacturing method 200 of an optical sheet for display according to the present invention is described. Although this manufacturing method is commonly applicable to all of the display optical sheets 10 to 60 already described, for convenience of description, it will be shown the case where this method is applied to the three-layer optical sheet for display (Example 3). will be.

The rollers 212B, 214B and 216B shown upwardly at the left end of FIG. 25 have a first diffusion sheet 12, a prism sheet 14 already described in the first embodiment shown in FIG. And a roller on which the second diffusion sheet 16 is wound, respectively.

The rollers 212B, 214B and 216B are rotated on a rotating shaft of a feeding device (not shown), and the first diffusion sheet 12, the prism sheet 14 and the second diffusion sheet 16 roller at substantially the same speed. Supplied from 212B, 214B, and 216B, respectively.

The supplied first diffusion sheet 12, prism sheet 14 and second diffusion sheet 16 are each by punching presses 217, 219 and 221 disposed downstream in the above-described planar size or shape. Punched (or through the formation of notches or holes) (punching step). On the other hand, the sheet residue 234 remaining after the punching guided by the guide roller G is wound around the winding roller 236 of the winding device (not shown in detail). Incidentally, FIG. 25 shows the winding roller 236 only of the sheet residue 234 of the second diffusion sheet 16, and shows the winding of the sheet residue from the first diffusion sheet 12 and the prism sheet 14. Is omitted.

Next, the first diffusion sheet 12 ', the prism sheet 14' and the second diffusion sheet (discharged to each of the conveyors 213A, 213B and 213C, and then punched into the aforementioned plane size or the aforementioned shape ( 16 ') is stacked by the suction robot 224 to the next bonding conveyor 215 (lamination step). The suction robot 224 movable laterally (in the direction of AB of FIG. 25) and longitudinally (in the direction of CD of FIG. 25) is a first diffusion sheet 12 ′ from bottom to top, a prism sheet 14 ′. And sheets stacked on the conveyors 213A, 213B, and 213C on the bonding conveyor 215 in the order of the second diffusion sheet 16 '. Thus, a pre-bonded laminated sheet construct 30 'is formed.

Accordingly, in the bonding step, the lamination sheet constitution 30 by joining only the second diffusion sheet 16 ′ which is the highest layer of the lamination sheet constitution 30 ′ and the first diffusion sheet 12 ′ which is the lowest layer by the bonding device 225. ') Is integrated (bonding step). As the bonding device 225, a welding means such as an impulse sealer (a sealer which performs heating by bringing current into an instant flow), a laser irradiation device, a high frequency welding device or an ultrasonic welding device, an adhesive, a double-sided adhesive tape, or the like may be used. Can be. Thereby, the laminated sheet structure 30 (optical sheet for display) bonded was produced accordingly. The bonded laminate sheet constructions 30 are transferred from the bonding conveyor 215 to the transfer conveyor 226 and are continuously mounted on the stacker 232 by the suction traversing device 228.

Until now, the above-described method of manufacturing the optical sheet for display can achieve 1) stripe defect reduction effect, 2) assembling human-labor reduction effect, and 3) protective sheet reduction effect, but the detailed description of these effects is given in the first description. It is omitted because it is similar to the detailed description of the embodiment. Further, the sheet (the optical sheet for display 10) punched out of the laminate of the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16, and the second diffusion sheet 18. The planar arrangement is similar to the planar arrangement of the first embodiment described with reference to FIGS. 10A and 10B.

According to the present invention, as described with reference to the first embodiment, 1) cost reduction and prevention of product value or thickness reduction and 2) performance improvement or reduction of light collection effect can be achieved. The details are similar to the details of the first embodiment.

Next, in the punching step, among the first diffusion sheet 12 ′, prism sheet 14 ′, and second diffusion sheet 16 ′ punched into a predetermined plane size or predetermined shape, the bonding device 225 is attached to the bonding device 225. The mode (first to sixth modes) in which only the second diffusion sheet 16 'which is the highest layer and the first diffusion sheet 12' which is the lowest layer is bonded is described.

26A and 26B make the plane size of the prism sheet 14 'of the intermediate layer between the first diffusion sheet 16' which is the highest layer and the second diffusion sheet 12 'which is the lowest layer smaller than the plane size of the highest and lowest layers. Punching step is achieved, and in the bonding step, the entire edges around the diffuser sheet 16 ', which is the highest layer, and the diffuser sheet 12', which is the lowest layer, are bonded so as to internally include the prism sheet 14 'of the intermediate layer. One mode is described. In the bonding procedure, heating may be applied first from the diffusion sheet 16 'side which is the highest layer, and then heating may be applied from the diffusion sheet 12' side which is the lowest layer (the same applies to the second to sixth modes as well. ).

Accordingly, the optical sheet for display, which is the laminated sheet constitution 30, is integrated in such a manner as to hold the prism sheet 14 'of the intermediate layer between the diffusion sheet 16' which is the highest layer and the diffusion sheet 12 'which is the lowest layer. Thus, the plurality of sheets 12 ', 14' and 16 'are maintained because the prism sheet 14' of the intermediate layer is held between the diffusion sheet 16 'which is the highest layer and the diffusion sheet 12' which is the lowest layer but is not bonded. ), Even if there is a difference in thermal expansion or contraction, bending (such as distortion or warpage) of the laminated sheet component 30 hardly occurs.

Alternatively, by joining only the diffusion sheet 16 ', which is the highest layer, and the diffusion sheet 12', which is the lowest layer, for example, all sheets 12 ', 14' including an intermediate layer welded by an impulse sealer to achieve bonding. And generation of molten material from the sheet as compared to the volume resulting from the welding of 16 '). Fuji Impulse Co., Ltd. Any known suitable impulse sealer such as the manufactured product can be used.

This serves to eliminate the problem of the molten material protruding out of the laminated sheet component 30 to change the dimensions after the bonding of the laminated sheet component 30. Further, by making the plane size of the prism sheet 14 'of the intermediate layer smaller than the plane size of the diffusion sheet 16' which is the highest layer and the diffusion sheet 12 'which is the lowest layer, the highest layer and the lowest layer to which the annular gap 234 is adhered to each other. The molten material 236 formed between the edges of and formed in the bonding process is received into this gap 234, resulting in the molten material being difficult to protrude out of the laminated sheet component 30. Incidentally, the most common planar shapes of the top, bottom and middle layers are rectangular, but there are no restrictions on the shape. However, these shapes are preferably similar to the shapes of the first mode. The full edges of the top and bottom layers are bonded in a continuous bond line in the first mode, and a plurality of locations at the edges of the top and bottom layers may be point glued, or only one of each full edge of the top and bottom layers, respectively. Only the sides may be joined.

27A and 27B show that the punching steps form respective sheets 12 ', 14' and 16 'of the top layer, the bottom layer and the middle layer in a rectangular shape of the same plane size, and the edge of the prism sheet 14' of the middle layer. A second mode is shown that is achieved by forming the notches 238 in at least one location on the top. In the bonding step, the highest layer of diffusion sheet 16 'and the lowest layer of diffusion sheet 12' are bonded through this notch 238.

Also in the second mode, the optical sheet for display, which is the laminated sheet constitution 30, is in the form of holding the prism sheet 14 'of the intermediate layer between the diffusion sheet 16', which is the highest layer, and the diffusion sheet 12 ', which is the lowest layer. Are stacked. Therefore, since the prism sheet 14 'of the intermediate | middle layer is hold | maintained without bonding to the diffusion sheet 16' which is the highest layer, and the diffusion sheet 12 'which is the lowest layer, it is among the some sheets 12', 14 ', and 16'. Even when there is a difference in thermal expansion or contraction, bending (such as distortion or warpage) of the laminated sheet component 30 hardly occurs. Further, by forming the notches 238 at at least one position on the edge of the prism sheet 14 'of the intermediate layer, the diffusion sheet 16' and the lowest layer in which the gap 240 of the matching shape of the notches 238 is the highest layer. The molten material 242 formed between the phosphorus diffusion sheet 12 'and generated in the bonding process is accommodated in this gap 240, making it more difficult for the molten material 242 to protrude out of the laminated sheet component. do. Incidentally, since the prism sheet 14 'of the interlayer is included internally in the first mode, the prism sheet 14' does not peel off the laminated sheet composition 30 when the composition is processed or in any other case. . However, as shown in FIGS. 27A and 27B, the bonding is achieved with only one side of the prism sheet 14 ′ of the interlayer through the notch 238 and the prism sheet (when the construction is processed or in any other case) Where the 14 ') may be peeled off and peeled off the laminated sheet constitution 30, the prism sheet 14' of the intermediate layer is bonded to the portion of the diffusion sheet 16 'which is the highest layer and the diffusion sheet 12' which is the lowest layer. It is desirable to. In this case, it is obviously necessary to join the edges which do not disturb the screen portion of the liquid crystal display element, and also to join the convex portions 239 and 239 to both sides of the notch 238. Incidentally, even in the first mode, the prism sheet 14 'of the intermediate layer may be bonded to portions of the diffusion sheet 16' which is the highest layer and the diffusion sheet 12 'which is the lowest layer. Although forming the notches 238 on one side of the prism sheet 14 'of the intermediate layer is shown in Figs. 27A and 27B showing the second mode, the notches may be formed on a plurality of sides.

28, a punching step is performed to form respective sheets 12 ', 14' and 16 'of the top layer, the bottom layer and the middle layer, which are rectangular shapes of the same plane size, and the edge of the prism sheet 14' of the middle layer. The hole 244 is formed in at least one position of, and only the diffusion sheet 16 'which is the highest layer and the diffusion sheet 12' which is the lowest layer show the third mode in which the hole 244 is bonded. In this case, the molten material from the diffusion sheet 16 ′ which is the highest layer and the molten material from the diffusion sheet 12 ′ which is the lowest layer are connected at the position of the hole 244. For this reason, it is preferable that the heating section uses an impulse sealer formed in a needle shape as the joining device 225, and achieve joining by instantaneous welding. The preferred size of the hole 244 is that the hole is not completely filled with molten material.

Also in the third mode, the optical sheet for display, which is the laminated sheet constitution 30, is in the form of holding the prism sheet 14 'of the intermediate layer between the highest diffusion sheet 16' and the lowest diffusion sheet 12 '. Are integrated. Therefore, since the prism sheet 14 'of the intermediate | middle layer is hold | maintained without bonding to the diffusion sheet 16' which is the highest layer, and the diffusion sheet 12 'which is the lowest layer, it heats among the several sheets 12', 14 'and 16'. Even when there is a difference in expansion or contraction, bending (such as distortion or warpage) of the laminated sheet component 30 hardly occurs. In addition, because the molten material from the diffusion sheet 16 'which is the highest layer and the molten material from the diffusion sheet 12' which is the lowest layer is received in the hole 244 and connected at the position of the hole 244, the rod of molten material is generates a state through which the rod passes through the hole 244. For this reason, by drilling the hole 244 in two positions, the risk of the part of the prism sheet 14 'peeling off and peeling off the laminated sheet constitution 30 can be eliminated.

29 shows that all four holes 244 are formed at four corners of the prism sheet 14 'of the intermediate layer, and only the uppermost diffusion sheet 16' and the lowest layer diffusion sheet 12 'have four holes ( 244 shows a fourth mode to be joined.

The fifth mode shown in FIG. 30 and the sixth mode shown in FIG. 31 are variations of the third mode of FIG. 28 and the fourth mode of FIG. 29, respectively. In the punching step, the sheets of the top layer, the bottom layer and the middle layer are punched into a rectangular shape of the same plane size, and through holes 246; 246A, 246B and 246C are formed at at least one position of each of the edges of the top layer, the bottom layer and the middle layer. . 30 shows nine through holes 246 in one side portion of the laminated sheet construction 30. In the bonding step, only the highest layer of diffusion sheet 16 'and the lowest layer of diffusion sheet 12' insert the bonding device 225 into the through hole 246 and the hole 246A of the highest layer of diffusion sheet 16 '. By melting around the periphery and the periphery of the hole 246C of the diffusion sheet 12 'which is the lowest layer, it joins through the hole 246B in the prism sheet 14' of an intermediate | middle layer. It is preferable that the joining device used in this case is an impulse sealer in which the heating part is shaped like a needle. The hole 246B formed in the prism sheet 14 'of the intermediate layer should be larger than the diameters of the needle-shaped member and larger than the holes 246A and 246C formed in the highest diffusion sheet 16' and the lowest diffusion sheet 12 '. Should be.

In addition, the fifth mode and the sixth mode may provide an effect similar to that of the third mode and the fourth mode.

Next, a bonding device 225 that is not an impulse sealer is described.

As the laser irradiation device, a YAG laser irradiation device having a wavelength of 355 to 1064 nm, a semiconductor laser irradiation device having a wavelength of about 800 nm, a carbon dioxide gas laser irradiation device having a wavelength of 9 to 11 μm, and the like can be used. The amplitude system may be continuous or may be pulse amplitude. 32 shows an example of the configuration of the semiconductor laser irradiation device 230. As shown in FIG. 32, the semiconductor laser irradiation device 230 includes a semiconductor laser amplitude amplifier 232, a laser controller 234 that controls the semiconductor laser amplifier 232, and a semiconductor laser amplitude through an optical fiber 236. It consists mainly of the laser head 238 connected to the machine 232, and the XY table 242 in which the laminated sheet component 30 'is mounted. The laser head 238 is provided with an optical capacitor (not shown), the laser beam guided by the optical fiber 236 is collected by the optical capacitor in the optical head 238, and the laminated sheet component 30 ' Investigate. For example, a semiconductor laser amplifier 232 having an amplitude wavelength of 808 nm is used at an output of 22 W, a laser beam diameter of 0.6 mm, and a scanning speed of 112 mm / s as a condition of laser irradiation for the first mode described above. The edges of the diffusion sheet 16 ', which is the highest layer, and the diffusion sheet 12', which is the lowest layer, were bonded to each other. The result has been the possibility of bonding strength or optical properties by bonding them that have no problem on the surface.

Incidentally, known mechanisms (such as suction devices) for sucking up smoke generated during bonding through a laser may also be provided.

When an adhesive is used as the bonding device 225, it is preferable that the adhesive is an adhesive that can be assisted by heat or a catalyst. In particular, such general adhesives such as silicone adhesives, polyurethane adhesives, polyester adhesives, epoxy adhesives, cyanoacrylate adhesives or acrylic adhesives can be used.

Since any display optical sheets 10 to 60 may be used at high temperatures, it is desirable to stabilize the usual temperature range of the adhesive to 120 ° C. Among the adhesives described above, epoxy adhesives can be suitably used because of high strength and heat resistance. Cyanoacrylate adhesives can be immediately used for the effective manufacture of optical sheets for displays in terms of effectiveness and high strength. Polyester adhesives are particularly suitable in view of high strength and ease of processing.

Although adhesives are broadly classified into two-part mixing types by thermosetting, hot melting and bonding methods, thermosetting hot melting types that allow for continuous production are preferred. Preferred application thickness of any adhesive is 0.5 μm to 50 μm.

It is also desirable to provide a drying device for drying the adhesive. There are no specific limitations to this drying device, but drying can be accomplished by any known method of drying with warm or hot wind, or drying with dehumidified wind.

Where a double-sided adhesive tape is used as the bonding device 225, a highly tacky acrylic copolymer resin can be used as the adhesive of the double side tape. Other available adhesives include silicone, natural rubber and synthetic rubber adhesives, but acrylic adhesives are preferred based on physical strength, including heat resistance, and an overall assessment of semi-strain properties and price.

33 shows an example of an ultrasonic welding device 300 primarily provided with an amplitude 302, a resonator 304, a booster 306, an ultrasonic horn 308 and an acceptable table 310. The air cylinder 316 is installed in a pressure strut 314 upright on the stool 312. The ultrasonic horn 308 is shifted by the air cylinder 316 in the lifting direction. When the ultrasonic horn 308 of this configuration was used for the first mode of bonding at an output of 1 kW and a pressing force of 34 kg, the result has no problem on the surface and has the possibility of combining the bonding strength or the optical properties. come.

(Fourth embodiment for carrying out the present invention)

A fourth embodiment for carrying out the present invention is described below with reference to the accompanying drawings. Incidentally, the configuration of the optical sheet for display (first to sixth examples) of the laminated sheet constitution type is the same as the configuration in the first embodiment described with reference to Figs. 1 to 6, using the same corresponding reference numerals. It is explained.

A manufacturing apparatus 400 for implementing the method of manufacturing the optical sheet for display according to the present invention is described. Although the manufacturing apparatus 400 is commonly applicable to all of the above-described display optical sheets 10 to 60, for convenience of description, the following details refer to the four-layer optical sheet for display (Example 1). Will be applied to the case.

FIG. 34 is a conceptual view showing an overall configuration of a manufacturing apparatus for an optical sheet for display, and FIG. 35 shows a perspective view.

As shown in FIGS. 34 and 35, the rollers 412B, 414B, 416B and 418B disposed toward the left end of the figure have a belt-shaped first diffusion sheet (described above with reference to FIG. 1) around them. 12), the first prism sheet 14, the second prism sheet 16, and the second prism sheet 18 are wound rollers, respectively.

The rollers 412B, 414B, 416B, and 418B are rotated on a rotating shaft of a feeding device (not shown), and have a belt-shaped first diffusion sheet 12, first prism sheet 14, and second prism sheet 16. And second diffusion sheet 18 may be supplied to each of rollers 412B, 414B, 416B, and 418B at substantially the same speed.

The supplied belt-shaped first diffusion sheet 12, first prism sheet 14, second prism sheet 16 and second prism sheet 18 are guided by guide rollers G, G, ... Each is held, and the other is stacked one on top on the upstream side of the punching press 448 described below. As a result, a belt-shaped laminated sheet structure is formed (lamination step). Geometrically, the belt-shaped laminated sheet construction before being punched by the punching press 448 is referred to as the uncut cut sheet construction 10 ', and punched to product size is simply referred to as the laminated sheet construction 10. do.

Next, the uncut sheet material 10 'for cutting is formed by a punching press 448 (not shown) and a plurality of laminated sheet material 10 equipped with a punching blade for the external shaping described in detail below. Punched by the punching blade 420, and at the same time one or more positions of the edges of the laminated sheet construction 10 are joined. On the other hand, the sheet residue 434 remaining after punching, guided by the guide roller G, is wound around the winding roller 436 of the winding device (not shown in detail).

Next, punching press 448 is described.

Punching press 448 is a device that cuts and simultaneously bonds the laminated sheet construct 10 'that is not cut into the laminated sheet construct 10 of a product size. This punching press 448 is provided with a joining punching blade 420 that joins one or more positions of the edge of the laminated sheet component 10 of the product size as well as a punching blade for external shaping used for punching to the product size. do. In particular, although not described above, the punching blade for external shaping is similar to the blade of any known punching press.

As shown in FIG. 36, the notch 421 is a joining punching blade 420 having a U-shaped section to enable the uncut cut sheet material 10 ′ to be punched leaving the connection 427. ), See FIG. 39. Thus, the notch 421 portion constitutes the connecting portion 427 after punching. Or, if the joining punching blade 420 is shown to have a U-shaped section in FIG. 36 and the connection 427 is left as C-shaped, cylindrical, rectangular or triangular, other than this shape It may have a different shape.

In addition, a pressing bar 419 is disposed inside the joining punching blade 420 having a U-shaped section. Pressing bar to impart a folding pattern to the connections 427 by punching the uncut cut sheet material 10 'through a bonding punching blade 420 that presses the connections 427, leaving the connections 427 in place. 419 is provided, whereby sufficient bonding force is prevented from being destroyed by the external force of the strength resulting from the treatment, and the laminated sheet constitution 10 is bonded through this bonding force. Thus, no blade is formed at the tip of the pressing bar 419.

The tip of the frising bar 419 is preferably flushed as the tip of the bonding punching blade 420. Even when the tip of the pressing bar 419 slightly dents or protrudes compared to the tip of the joining punching blade 420, the effect of folding back the punched portion under pressure can be achieved, but the same This ensures the achievement of the effect of keeping the couple punched under pressure.

The punching press 448 is equipped with a plurality of sets of each of an external shaping punching blade and a joining punching blade 420. The number of punching blades 420 for bonding in one set of punching blades need not be one, but as many as the number of joints, and the edges of the product sized laminated sheet construction 10 (eg, of the laminated sheet construction). A plurality of blades is arranged to match the positions where the four corners) are joined. Further, when the uncut cut sheet material 10 'is punched through the bonding punching blade 420, the mounting base 422 on which the uncut cut sheet material 10' is mounted is attached to the punching blade for bonding. It must be a material that causes 420 to cut it.

In addition, the bonding punching blade 420 is punched out of the uncut sheet material 10 'that is not cut when the bonding punching blade 420 after punching the uncut cut sheet material 10' is removed. A pressing device may be provided that can press on the periphery of the position. However, for ease of explanation, this pressing device is described in connection with another embodiment (punching press 448 ').

Since the punching press 448 is configured as described above, a plurality of laminated sheet constructs 10 of product size can be formed, and at the same time, at least one portion of each laminated sheet construct 10 of the product size is It can be joined by punching the uncut laminate sheet construct 10 '. Incidentally, the details of the present embodiment assume that the punching press 448 is provided with both the external shaping punching blade and the bonding punching blade 420, but the external shaping punching blade and the bonding punching blade 420, respectively. May be disposed on a separate punching press.

Next, a mechanism for joining the laminated sheet component 10 by the punching press 448 using the joining punching blade 420 and the punching bar 419 is described with reference to FIGS. 37 to 39. Incidentally, FIGS. 37 and 38 are views of the arrow direction cut along the line A-A of FIG. 36, and FIG. 39 is a view of the arrow direction cut along the line B-B of FIG. 36.

As shown in FIG. 37, the bonding punching blade 420 is moved downward in the direction of the arrow E of FIG. 36, so that the laminated sheet component 10 ′ is not cut, leaving the connection portion 427 as shown in FIG. 39. Punch. As shown in FIG. 40, an ultra-small enlarged view of a section punched out of the uncut sheet of laminated sheet construction 10 ′ with the connections 427 left in this manner is shown on the optical sheet on both sides of the punching line 431 as a boundary. By the formation of a defective structure. This defective structure causes the optical sheets on both sides of the punching line 431 to span different layers and engage with each other.

38 and 39 described above show the shape after punching the uncut sheet structure 10 'with the connection 427 left. The placement of the punching bar 419 in the joining punching blade 420 as in the punching press 448 is such that even after the joining punching blade 420 is completed, the folding pattern is connected as shown in circle R in FIG. 39. 427 and maintain this shape. This enables a state of engagement of the more rigid optical sheets with each other.

Incidentally, the edge angle θ of the joining punching blade 420 and the planar arrangement of the joining punching blade 420 in the punching press 448 are described with reference to another embodiment (punching press 448 ').

Next, punching press 448 'is described in another embodiment. Incidentally, the same or similar members and the like as the corresponding portions in Fig. 36 are designed by the same individual reference numerals, and the detailed description thereof is omitted. Punching press 448 ′ is not provided with a pressing bar 419.

As shown in FIGS. 41 and 42, the notch 421 is cut at the joining cylindrical punching blade 420 to allow the uncut laminated sheet construction 10 ′ to be punched leaving the connection 427 ( 39). Thus, the notch 421 portion constitutes the connecting portion 427 after punching. Also, the joining punching blade 420 is shown to have a cylindrical shape in FIG. 41, and any limitations on the shape are allowed if this shape is allowed to be punched through the remaining connection 427 as described above. none. In general, the diameter L3 of the punching blade 420 for joining is preferably cylinder-shaped such that the diameter becomes larger or smaller depending on the shape of the cylinder, but becomes 1 mm to 20 mm.

The bonding punching blade 420 is around the punched position of the uncut laminated sheet component 10 'when the unbonded laminated sheet component 10' is removed after the bonding punching blade 420 is punched out. A pressing device 423 is provided to pressurize. As the pressing device 423, a sponge member which is wound around the upper circumference of the bonding punching blade 420 and whose upper end is fixed to the holding member 424 as shown in FIGS. 41 and 42 is suitable, for example. Can be used. This arrangement allows the sponge member to expand and contract with the joining punching blade 420 as its axis center.

The distance L1 from the tip of the joining punching blade 420 to the sponge member is determined by the thickness of the uncut sheet laminate 10 'and the distance at which the joining punching blade 420 is cut into the mounting base 422. It is formed to be shorter than the whole (L2). This results in the tip of the sponge member being in contact with the top face of the uncut laminated sheet component 10 'when the uncut sheet composition 10' is punched and for pressing the periphery of the punched position. Try to contract the reaction force.

Since a spring or the like can be used as the pressing device 423, its spring force must not be too strong, but the uncut laminated sheet component 10 ′ is transferred to the state punched by the bonding punching blade 420. The spring force must be sufficient to prevent it from returning to the state.

Since the punching press 448 'is configured as described above, a plurality of laminated sheet constructs 10 of product size can be formed by punching uncut laminated sheet constructs 10', each of the product sizes. At least one position may be bonded at the edge of the laminated sheet construction 10.

Next, the mechanism for joining the laminated sheet component 10 by the joining punching blade 420 is described with reference to FIGS. 43A, 43B, and 43C. As shown in FIG. 43A, the joining punching blade 420 is moved downward in the direction of the arrow A so as not to be cut, leaving the connecting portion 427 as shown in FIGS. 43A and 43B. Punch.

As shown in FIG. 40, a micro-expanded view of the section punched out of the uncut sheet of laminated sheet construction 10 ′ with the connections 427 left in this manner is provided as a boundary to the optical sheet on both sides of the punching line 431. By the formation of a defective structure. This defective structure causes the optical sheets on both sides of the punching line 431 to span different layers and engage with each other.

In addition, when removing the bonding punching blade 420, the presence of the punching device 423 can remove the defective structure in which the bonding punching blade 420 is held. This makes it possible to prevent the laminated sheet component 10 from bonding with sufficient bonding force and destroying the component by the external force of the strength resulting from the treatment.

In this case, as shown in FIG. 42, it is preferable that the edge angle (theta) of the punching blade 420 for joining becomes 43 degrees or more. This is because the blade is too sharp so that a defective structure is formed when the edge angle θ is less than 43 °.

Further, as shown in Figs. 44A to 44C, it is preferable that a pair of punched shapes are formed to face each other at close positions. Forming a pair of punched shapes opposite each other at close locations may have stronger bonding forces than when a pair of punched shapes 425 are formed randomly. Although the reason for the stronger force is not correct, it is believed that the pair of punched features 425 are formed opposite each other at close locations (e.g., mutual pushing force or pulling force) as described above. To work on a punched section.

In this case, since the distance greater than 20 mm between the pair of punched shapes 425 weakens the bonding force, the close distance L4 is preferably less than 20 mm. Further, the number of connecting portions 427 need not be limited to one, but forming a large number of connecting portions 427 makes it difficult to form a defective structure.

The bonding position of the laminated sheet component 10 or the number of bonded portions is not particularly limited, but when they are at the periphery, a plurality of bonded portions may be formed on one side of the peripheral portion of the laminated sheet component, as shown in FIG. And the laminated sheet construction may be bonded at four corners around it, as shown in FIG. 46.

Punching is not limited to only one side of the laminated sheet construction, but there may be all of the punched shapes 425 formed on one side as shown in FIG. 47. The defect structure between the front and back sides of the laminated sheet construction 10 may contribute to increasing the bonding force.

Since the laminated sheet construction 10 is joined by punching through the bonding punching blade 420 in this manner according to the invention, the molten material is dimensional accuracy of the laminated sheet construction 10 as in the case of applying the welding method. Does not deteriorate. In addition, the bonding force is weaker than that of welding or bonding, and the bonded laminate sheet construction 10 is not affected from bending resulting as a result of differences in thermal expansion or contraction among the plurality of types of optical sheets.

The method and apparatus for manufacturing the optical sheet for display described so far can provide 1) stripe defect reduction effect, 2) assembling human-labor saving effect, and 3) protective sheet reduction effect. It is omitted because it is similar to the effect of the first embodiment. Further, sheets punched outside the laminate of the first diffusion sheet 12, the first prism sheet 14, the second prism sheet 16, and the second diffusion sheet 18 (optical sheet for display 10) ) Is similar to the planar arrangement in the first embodiment described with reference to FIGS. 10A and 10B.

According to the present invention, as described with reference to the first embodiment, 1) cost reduction and product value enhancement or thickness reduction and 2) performance improvement or prevention of deterioration in the light collection effect can be achieved. The details are similar to the details of the first embodiment.

Incidentally, although the present invention is described with reference to the examples of the optical sheet for display and its manufacturing method and apparatus, the present invention is not limited to the above-described examples of embodiments, but can be realized in various other embodiments.

For example, the uncut laminate sheet construction 10 ′ remains punched leaving the connection 427 in all cases of the exemplary embodiments described above, although the punched shape has a connection 427 as the base end. A folding back step is added which is folded back towards the back side of the laminated sheet construction 10. In this way, as many steps are increased, the fixing between the optical sheets is made more robust.

Although the interlayer configuration of the optical sheet for display is not limited to the examples of the embodiment, for example, the protective sheets may be laminated on the top layer and below the bottom layer. This configuration functions similarly to the above-described embodiment and provides a similar effect.

EXAMPLE

(1) Example in 1st Embodiment of this invention

[Production of Prism Sheet]

The prism sheet used as the 1st prism sheet 14 and the 2nd prism sheet 16 was produced. This prism sheet will be commonly used as the first prism sheet 14 and the second prism sheet 16.

Control of resin solution

The chemical compounds listed in the table of FIG. 48 were mixed in the weight ratios described herein, and the mixture was heated to 50 ° C., stirred and dissolved to obtain a resin solution. The names and features of the compounds are listed below.

EB3700: Ebecryl 3700, Daicel UC Co., Ltd. Manufacture, Bisphenol A type epoxy acrylate, (viscosity: 2200 mPas / 65 ° C)

BPE200: NK ester BPE-200, Shin-Nakamura Co., Ltd. Ethylene oxide-added bisphenol A methacrylate ester, (viscosity: 590 mPas / 25 ° C.)

BR-31: New Frontier BR-31, Dai-ichi Kogyo Seiyaku Co. Ltd. Tribromophenoxy ethyl acrylate, (solid at room temperature above M.P.

LR8893X: Lucirin LR8893X, BASF Japan Ltd. Preparation of optical radical generator, ethyl-2,4,6-trimethylbenzoyl ethoxy phenyl phosphine oxide

MEK: Methyl Ethyl Ketone

A prism sheet manufacturing method of the configuration as shown in FIG. 49 was used to achieve prism sheet production 580.

As the sheet W, a transparent polyethylene terephthalate (PET) film having a width of 500 mm and a thickness of 100 μm was used.

As the emboss roller 583, an S45C roller of 700 mm in length (width direction of the sheet W) and 300 mm in diameter having a nickel surface was used. Grooves of 50 μm pitch were formed completely around the surface of the roller in a width of about 500 mm by cutting through the (single-pointed) diamond bite. The shape of the section was triangular, 90 degrees triangle with a vertex angle and the bottom of the lube had no plan view. Thus, the grooves are 50 μm wide and have a depth of about 25 μm. Since the groove does not have any joint in the circumferential direction of the roller and runs endlessly, a lenticular lens (prism lens) having a triangular section can be formed on the sheet W through the emboss roller 583. The surface of the roller was plated through nickel after the groove was cut.

As the liquid supply device 582, a die coater having an extruded supply head 582C was used.

The feed liquid F (resin solution) used has the composition described in the table of FIG. 48 described above. The supply amount of the liquid F supplied to the supply head 582C is controlled through the supply device 582B to make the film thickness of the liquid F (resin) supplied in the wet state after drying of 20 µm of the organic solvent.

As the drying device 589, a circulation type hot air drying device was used. The temperature of the hot air was 100 ° C.

As the nip roller 584, a roller having a 200 mm diameter having a silicone rubber layer having a rubber hardness of 90 was used. The nip pressure at which the sheet W was pressurized with the emboss roller 583 and the nip roller 584 (effective nip pressure) was 0.5 Pa.

As the resin curing device 585, a metal halide lamp was used, which was irradiated with an energy of 1000 mJ / cm 2.

This procedure provided a prism sheet with an uneven pattern formed thereon.

[Production of First Diffusion Sheet 12]

The first diffusion sheet 12 (diffusion sheet for lower use) was prepared by producing a sequence of an undercoat layer, a backcoat layer, and a light diffusion layer through the following method.

Undercoat layer

Liquid A, which is applied to the undercoat layer of the composition below, is applied to one surface of a polyethylene terephthalate film (support) having a thickness of 100 μm through a wire bar (wire size # 10), and dried at 120 ° C. for 2 minutes. , An undercoat layer having a film thickness of 1.5 μm was obtained.

(Liquid applied to the undercoat layer)

Methanol 4165g

Julymer SP-50T (manufactured by Nihonjunyaku Co., Ltd.) 1495 g

Cyclohexanone 339 g

Julymer MB-1X (manufactured by Nihonjunyaku Co., Ltd.)

(Organic particles: spherical ultrafine particles of crosslinked type polymethyl methacrylate, average weight particles having a diameter of 6.2 μm)

Backcoat layer

Liquid B as a liquid applied to the backcoat layer of the following constituents was applied to the side opposite to the undercoated side of the support supplied with the wire bar (wire size # 10), and dried at 120 ° C. for 2 minutes, A backcoat layer with a film thickness of 2.0 μm was obtained.

(Liquid applied to the backcoat layer)

Methanol 4171g

Julymer SP-65T (manufactured by Nihonjunyaku Co., Ltd.) 1487 g

Cyclohexanone 340 g

Julymer MB-1X (manufactured by Nihonjunyaku Co., Ltd.)

(Organic particles: spherical ultrafine particles of crosslinked type polymethyl methacrylate, average weight particles having a diameter of 6.2 μm)

-Light diffusion layer

Liquid C as a liquid applied to the light diffusing layer of the following constituents was applied to the undercoated side of the support whose wire bar (wire size # 22) was prepared as described above, and dried at 120 ° C. for 2 minutes, and then A diffusion layer was obtained. As described in more detail below, two versions of the light diffusing layer are obtained, one being applied immediately after the preparation of liquid C, and the other allowing to remain still for two after the adjustment of liquid C. Will be.

(Liquid applied to the light diffusion layer)

20.84 g of cyclohexanone

Disparlon PFA-230, solid content 20 mass% 0.74 g

(Particle fall prevention agent: fatty acid amide, manufactured by Kusumoto Chemicals, Ltd.)

20.% by mass acrylic resin of methyl ether ketone solution (Dianal BR-117, manufactured by Mitsubishi Rayon Co., Ltd.) 17.85 g

Julymer MB-20X (manufactured by Nihonjunyaku Co., Ltd.) 11.29g

(Organic particles: spherical ultrafine particles of crosslinked type polymethyl methacrylate, average weight particles having a diameter of 18 μm)

F780F (manufactured by Dainippon Ink and Chemicals, Incorporated) (30% by mass 0.03 g of methyl ether ketone solution)

[Production of Second Diffusion Sheet 18]

The second diffusion set 18 has the same conditions as the first diffusion sheet 12 except that the amount of Julymer MB-20X added to the light diffusion layer of the first diffusion sheet 12 is changed from 11.29 g to 1.13 g. In the same flow.

[Method of Manufacturing Optical Sheet for Display]

As shown in FIG. 3, the configuration of the optical sheet for display includes the first optical sheet 12, the first prism sheet 14, and the second diffusion sheet 18 in order from bottom to top. It was the structure of the sheet | seat 30 (optical sheet module). The junction part 30A was the form shown to FIG. 7A and FIG. 7B (one long side).

As the heat-adhesive film 80, Nihon Matai Co., Ltd. The heat adhesive film manufactured by (Product name: Elphan PHE411 (polyester)) was used.

Thermal adhesive films 80 having a width (width W in FIGS. 7A and 7B) of 1 mm, 2 mm, 3 mm, 4 mm and 5 mm have already been made. The thicknesses of the heat-adhesive films 80 of different widths are 0.05 mm (0.02 mm after adhesion), 0.1 mm (0.05 mm after adhesion), 0.2 mm (0.1 mm after adhesion) and 0.3 mm (0.15 after adhesion), respectively. Mm).

The temperature of the sealing portion of the impulse sealer 72 was set to 150 ° C., and the pressure was set to 0.2 MPa (2 kgf / cm 2).

[Evaluation of Optical Sheet for Display]

The prepared optical sheet was integrated into a commercial liquid crystal display (backlit unit), and the adhesion state and the presence or absence of the interference fringes were evaluated.

As for the evaluation of the adhesion state, when only the second diffusion sheet 18 on the upper surface is lifted up, when the bonding portion 30A between the sheets is not removed, the state is judged to be good, and the bonding portion 30A is merely If partially removed, the condition was judged to be poor.

With respect to the evaluation of the presence or absence of the interference fringes, the composition which does not cause any interference fringes due to the heat-adhesive film is evaluated as good, and the composition when any interference fringes due to the heat-adhesive film is observed is poor. Was evaluated.

As a general assessment, good in both the adhesion state and the presence or absence of interference fringes was evaluated as acceptable.

The results of this evaluation are written together in the table of FIG. This table shows that the construction of the heat-adhesive film having a width of 2 to 4 mm and its thickness of 0.05 to 1 mm is good in the overall evaluation.

Those evaluated as poor in the overall evaluation have been found to be inferior to the conventional optical sheets for display, and can be used for the backlight unit. Thus, various advantages of the present invention have been identified.

(2) Example of the second embodiment of the present invention

As the prism sheet, the first diffusion sheet 12 and the second diffusion sheet 18 were manufactured in the same manner as in the example in the first embodiment of the present invention, and the description thereof is omitted.

In view of the configuration of the optical sheet for dispensing, the first diffusion sheet 12, the first prism sheet 14, and the second diffusion sheet ( It was an optical sheet for display 30 (optical sheet module) constructed by laminating in the order of 18). Junction 30A was in the form shown in FIGS. 7A and 7B (one long side). Pitch P of the through-holes 180, 180, ... was 90 mm.

The optical sheets were interlocked with each other by using the device 152 for drilling through holes shown in FIG. 12. The set temperature of the heater block 158 was monolithic to 280 ° C in all cases.

The diameter of the tip N1 of the needle-shaped member N was changed in seven steps from 0.2 mm of level 1 to 2.3 mm of level 7.

[Evaluation of Optical Sheet for Display]

The diameter of the through hole 180 after the manufactured optical sheet for display was standardized was measured through a counter microscope. In addition, the connection state of the manufacturing optical sheet for display was evaluated, and the qualitative ecology of the normalized through hole 180 was evaluated. An overall evaluation was made based on the results of these individual sentence values.

The criteria of the evaluation (good or bad) and the results of the evaluation are shown in the table of FIG. 51.

The results provided in this table show that the evaluation is good in all embodiments in the diameter range of the tip N1 of the needle-shaped member N of 0.3 to 2.0 mm. On the other hand, overall evaluation is inferior in the diameter 0.2mm which is less than 0.3 mm which is a lower limit, and also in the diameter 2.3mm which is more than 2.0 mm which is an upper limit.

(3) Example of the third embodiment of the present invention

The prism sheet 14 ', the first diffusion sheet 12' and the second diffusion sheet 16 'are manufactured in the same manner as in the respective counterparts in the example in the first embodiment of the present invention, the details of which Description is omitted.

The following examples were performed by using these sheets.

Example 1 First Embodiment

The rectangular prism sheet 14 'of the middle layer is punched to be shorter than 6 mm in the length of each of the sides of the diffused sheet 16' which is the rectangular top layer and the diffused sheet 12 'which is the rectangular bottom layer, and these sheets are top to bottom. The diffusion sheet 16 ', the prism sheet 14', and the diffusion sheet 12 'were stacked in this order. Only the top layer diffusion sheet 16 'and the bottom layer diffusion sheet 12' do not disturb the prism sheet 14 'and do not allow the molten material 236 to enter the interior from the end to each side of the top and bottom layers. It was bonded using an impulse sealer 225 (manufactured by Fuji Impulse Co., Ltd.). Heating and cooling times for proper welding are about 2 seconds and about 5 seconds, respectively.

As a result, satisfactory bonding has been successfully achieved without any problems with the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 30. Over time, no bending of the optical sheet for display was observed.

(Example 2) 2nd Embodiment

Notch 238 is cut at one side of rectangular prism sheet 14 'of the intermediate layer to have a groove depth of 10 mm (with a convex height of 10 mm on both sides of notch 238), diffusion sheet 16'. , Prism sheet 14 'and diffusion sheet 12' were laminated in order from above. Only the diffusion sheet 16 'which is the highest layer and the diffusion sheet 12' which is the lowest layer are bonded by using the impulse sealer 225 (manufactured by Fuji Impulse Co., Ltd.), without disturbing the prism sheet 14 ', The molten material 236 is prevented from entering 3 mm from each side end of the top and bottom layers matching the notch 238. In the convex part 239, bonding was performed at the one-point of the diffusion sheet 16 'which is the highest layer and the diffusion sheet 12' which is the lowest layer.

As a result, satisfactory bonding has been successfully achieved without any problems with the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 30. Over time, no bending of the optical sheet for display was observed. Incidentally, the width of the convex portion 239 (ie, the width of the notches 238), the number and arrangement thereof can be changed as desired.

(Example 3) Third Embodiment

The top layer, the bottom layer, and the middle layer were punched into rectangular shapes of the same plane size, and nine holes 44 of 2 mm diameter were formed in the prism sheet 14 'at 20 mm intervals, and the top layer was the diffusion sheet 16'. The lowest layer, the diffusion sheet 12 'was joined through the holes 244 using a spot type ultrasonic welding machine that measures a diameter of 1.3 mm.

As a result, satisfactory bonding has been successfully achieved without any problems with the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 30. Over time, no bending of the optical sheet for display was observed.

(Example 4) 6th Embodiment

The top layer, the bottom layer and the middle layer were punched into rectangular shapes of the same plane size, and holes 2.5 mm diameter 246B, respectively, were formed at four corners of the prism sheet 14 ', and holes 1.5 mm diameter holes 246A and 246C. In order to form this through hole 246, it was formed in the diffusion sheets 12 'and 16'. A portion of the through hole 246 was welded through an impulse sealer 225 in which the heating section was needle-shaped.

As a result, satisfactory bonding has been successfully achieved without any problems with the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 30. Over time, no bending of the optical sheet for display was observed.

(4) Example of the fourth embodiment of the present invention

As the prism sheets 14 and 16, the first diffusion sheet 12 and the second diffusion sheet 18 are manufactured in the same manner as in the respective counterparts in the example in the first embodiment of the present invention, the details of which Description is omitted.

The following examples were performed by using these sheets.

(Example 1)

The sheet configuration of the optical sheet for display corresponds to the first example shown in FIG. 1.

Thus, as shown in FIGS. 34 and 35, the belt-shaped first diffusion sheet 12, the first prism sheet 14, and the second prism sheet supplied to the outside of the rollers 412B, 414B, 416B, and 418B. 16 and second diffusion sheet 18 were laminated to the upstream side of punching press 448, and the belt-shaped uncut laminated sheet construction 10 'resulting from the lamination was punched blades and bonding for external shaping. It was punched through a punching press 448 equipped with a dragon punching blade 420.

The joining punching blade 420 used provided a U-shaped punched shape 425 and its edge angle, U-width of U-width and U-height of a pair of sides spaced 3 mm apart from each other. It was 45 degrees, 1.5 mm, and 2.0 mm respectively through the U shape. As shown in FIG. 46, four punching shapes 425 each comprising a pair of opposing flats are applied to each of the four corners of the edge of the laminated sheet construction 10, ie, 16 on the stack plane in total. Holes were formed at right angles.

As a result, satisfactory bonding has been successfully achieved without any problems on the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 10. Over time, no bending of the optical sheet for display was observed.

(Example 2)

As shown in FIG. 45, Example 2 is laminated via a punching blade 420 for joining by punching six pairs of punching shapes 425, ie, all twelve holes, each pair comprising opposing holes. Bonded to one side of the edge of the sheet construct 10. Other conditions were the same as in Example 1.

As a result, satisfactory bonding has been successfully achieved without any problems on the external dimensions, the appearance (without bending), the adhesive strength and the optical performance of the optical sheet for display, which is the laminated sheet component 10. Over time, no bending of the optical sheet for display was observed.

Claims (55)

As an optical sheet for display, Two or more optical sheets are laminated therein, And the optical sheets are bonded to each other at each one peripheral side by a heat-adhesive film. As an optical sheet for display, Two or more optical sheets are laminated therein, And the optical sheets are bonded to each other at each of two or more peripheral sides by a heat adhesive film. The method according to claim 1 or 2, And the thermal adhesive film is located between the optical sheets at the peripheral side or the peripheral sides. The method of claim 3, wherein And the thermal adhesive film is disposed at a position from 2 to 4 mm from an edge of the optical sheets. The method according to claim 1 or 2, And the heat-adhesive film is bonded to the cross sections of the optical sheets at the peripheral side or peripheral sides. The method according to any one of claims 1 to 5, The optical sheet for display after the adhesion, the thickness of the thermal adhesive film is 0.1 mm or less. The method according to any one of claims 1 to 6, The thermal adhesive film is a polyester film, an optical sheet for display. The method according to any one of claims 1 to 7, And the optical sheets comprise a diffusion sheet. The method according to any one of claims 1 to 8, And the optical sheets comprise a lens sheet in which convex lenses formed in one axial direction are disposed adjacent to each other and substantially all over the surface. The method according to any one of claims 1 to 9, And the optical sheets comprise two or more sheets of the same optical performance. The method according to any one of claims 1 to 10, The stack of optical sheets is used for a backlight unit of a display device. Two or more optical sheets are laminated, A through-hole or through-holes are formed in at least one portion of the edge of the laminated stack, and the optical sheets are engaged with each other by the through-holes or through-holes. The method of claim 12, And the through holes or through holes are formed by melting the optical sheets. The method according to claim 12 or 13, And the through holes or through holes are disposed at positions up to 3 mm from the edges of the optical sheets. The method according to any one of claims 12 to 14, The through hole or through hole has a diameter of 0.3 to 2.0mm, the optical sheet for display. The method according to any one of claims 12 to 15, The through hole or through holes are formed by a heated needle-shaped member. The method according to any one of claims 12 to 16, The optical sheet for display, wherein the density of the through holes in the mutually engaging portion of the optical sheets is 2 or more per cm 2. The method according to claim 16 or 17, The mutually engaging portions of the optical sheets are pressed by retaining members from above and below when the through holes or through holes are formed by the heated needle-shaped member. The method of claim 18, An insertion hole or insertion holes or insertion grooves or insertion grooves for allowing the needle-shaped member to be inserted are formed in one or both of the retaining members. The method of claim 16 or 17, When the through-holes or through-holes are formed by the heated needle-shaped member, an upper retaining member having an insertion hole for inserting the needle-shaped member and a lower retaining member having an insertion groove for inserting the needle-shaped member are formed. And the mutually engaging portions of the optical sheets are squeezed therebetween. The method of claim 19 or 20, An optical sheet for display, wherein the diameter of the insertion hole and / or the width of the insertion groove is 1.02 to 4 times the diameter of the needle-shaped member. The method according to any one of claims 12 to 21, And the optical sheets comprise a diffusion sheet. The method according to any one of claims 12 to 22, And the optical sheets comprise a lens sheet in which convex lenses formed in one axial direction are disposed adjacent to each other and substantially all over the surface. The method according to any one of claims 12 to 23, wherein And the optical sheets comprise two or more sheets of the same optical performance. The method according to any one of claims 12 to 24, The stack of optical sheets is used for a backlight unit of a display device. A table holding two or more laminated optical sheets; An elevating stage for elevating a plurality of needle-shaped members; And A heating device for heating the needle-shaped members, And the heated needle-shaped members are capable of forming through holes in a plurality of positions at an edge of the stack of optical sheets. A table holding two or more laminated optical sheets; An elevating stage for elevating a plurality of needle-shaped members; A holding member, wherein each of the holding members is provided with an insertion hole for allowing the needle-shaped member to be inserted, and presses an edge of the stack of optical sheets; And A heating device for heating the needle-shaped members, The retaining members press against an edge of the stack of optical sheets, And the heated needle-shaped members are capable of forming through holes in a plurality of positions at an edge of the stack of optical sheets. A method of manufacturing an optical sheet for display comprising a laminating step wherein a laminated sheet composition formed by laminating three or more optical sheets is bonded at at least one position of its edge to integrate the composition. A method for manufacturing an optical sheet for display, wherein only the optical sheet constituting the highest layer and the optical sheet constituting the lowest layer of the laminated sheet constitution are bonded in the bonding step. The method of claim 28, For forming the intermediate layer of the optical sheets between the highest layer and the lowest layer of optical sheets in a plane size smaller than the optical sheets of the highest layer and the lowest layer, whereby only the optical sheets of the highest layer and the lowest layer are bonded. Method of manufacturing the optical sheet. The method of claim 29, And the intermediate layer of the optical sheets is included internally by bonding the entire edges of the top and bottom layers of optical sheets. The method of claim 28, An optical sheet for display, wherein a notch is cut at at least one position of an edge of an intermediate layer of the optical sheets between the top layer and the bottom layer, and only the top layer and the bottom layer optical sheets are bonded through the notch. How to manufacture. The method of claim 28, A hole is formed in at least one position of an edge of the intermediate layer of the optical sheets between the top and bottom layers, wherein only the top and bottom optical sheets are bonded through the hole. Way. The method according to any one of claims 28 to 32, Wherein said top layer and said bottom layer of said three or more optical sheets are optical sheets of the same kind. The method according to any one of claims 28 to 33, wherein Wherein said three or more optical sheets comprise a lens sheet and a diffusion sheet, said diffusion sheets being disposed in said top layer and said bottom layer. The method according to any one of claims 28 to 34, wherein And the optical sheet of the intermediate layer is bonded to a part of the top layer and / or the bottom layer. An optical sheet for display integrated by bonding at least one position of an edge of a laminated sheet component formed by laminating three or more optical sheets, An optical sheet for display, wherein only the highest optical sheet and the lowest optical sheet of the laminated sheet constitution are bonded. The method of claim 36, The intermediate layer of the optical sheets between the top layer and the bottom layer is formed in a planar size smaller than the top and bottom layers of optical sheets, and the middle layer of the optical sheets forms the entire edges of the top and bottom layers of optical sheets. Optical sheet for display contained internally by bonding. The method of claim 36, Wherein the notch is cut at at least one position of the edge of the intermediate layer of the optical sheets between the top and bottom layers, and only the top and bottom optical sheets are bonded through the notches. The method of claim 36, And a hole is formed in at least one position of an edge of the intermediate layer of the optical sheets between the top layer and the bottom layer, and only the top and bottom optical sheets are bonded through the hole. The method according to any one of claims 36 to 39, Wherein said three or more optical sheets comprise a lens sheet and a diffusion sheet, said diffusion sheets being disposed in said top layer and said bottom layer. A method of manufacturing an optical sheet for display comprising a bonding step of integrating a laminated sheet component formed by laminating a plurality of optical sheets at one or more positions of an edge thereof to integrate the component. Wherein the laminated sheet construction is bonded in the bonding step by punching the periphery of the laminated sheet construction into a predetermined punched shape leaving a connection. 42. The method of claim 41 wherein Wherein said punching is formed in a C shape or a U shape. 43. The method of claim 41 or 42, And a pair of the punched shapes are opposed to each other. The method according to any one of claims 41 to 43, Wherein the laminated sheet construction is punched out leaving a connection, and the connection is pressed in the bonding step. The method according to any one of claims 41 to 44, Wherein the ratio of the connection length to the total outer circumferential length of the punched shape is 50% or less. The method according to any one of claims 41 to 45, And said punching is performed with punching an uncut, laminated sheet component having a planar size of the sheet greater than the product size into the laminated sheet component of the product size. The method according to any one of claims 41 to 46, And said punching is performed to form said punched shape at two or more positions of a periphery of said laminated sheet construction. The method according to any one of claims 41 to 47, Folding back the portion of the punched shape toward the rear face of the laminated sheet construction with the connection at the base end. . An apparatus for manufacturing an optical sheet for display having a bonding device for integrating a laminated sheet structure formed by laminating a plurality of optical sheets by bonding at one or more positions of the periphery thereof. The bonding device is an apparatus for manufacturing an optical sheet for display, which is a punching press device having a punching blade for joining, in which a notch for punching the component is left without a connecting portion. The method of claim 49, The outer circumferential portion of the bonding punching blade is provided with a pressing device for pressing the vicinity of the punching position in the laminated sheet construction when the bonding punching blade is pulled out after punching the laminated sheet construction. Device for manufacturing. 51. The method of claim 49 or 50, Wherein the bonding punching blade is C-shaped or U-shaped, and a pressure bar is disposed inside the C-shaped or the U-shaped of the bonding punching blade. The method of claim 51 wherein And the tip of the pressure bar is on the same plane as the tip of the bonding punching blade. The method of any one of claims 49-52, And said bonding punching blade is disposed over at least two sides of said periphery of said laminated sheet construction. The method of any one of claims 49-53, Wherein said bonding punching blade is disposed in a punching press for punching an uncut laminated sheet component having a planar size of the optical sheet larger than the product size into the laminated sheet component of the product size. An optical sheet for display integrated by bonding the composition at one or more positions of the periphery of the laminated sheet composition formed by laminating a plurality of optical sheets, Wherein the laminated sheet construction is bonded to each other by engaging the optical sheets in the punched section by punching in a predetermined punching shape leaving the periphery of the laminated sheet construction intact.

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