JP2013079987A - Display window panel and method of manufacturing display window panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display window panel which can easily obtain a desired antireflection effect and suppress a manufacturing cost and a method of manufacturing the display window panel.SOLUTION: A display window panel for an electronic apparatus at least comprises a tabular substrate in which a minimal pattern of a moth-eye structure is formed on one face and which has high transparency, and an antireflection sheet attached to the other face of the substrate through an adhesive material.

Description

  The present invention relates to a display window panel of an electronic device in which an antireflection treatment is performed on one surface and the other surface of a synthetic resin substrate having high transparency, for example, and a method for manufacturing the display window panel.

  Conventionally, in an electronic device represented by a flat panel display, a digital camera, a digital video camera, a mobile phone, a portable game machine, etc., by disposing a display window panel that has been subjected to antireflection treatment on its display part, Visibility can be maintained well while the display portion is well protected.

  Such a display window panel is formed, for example, by forming an antireflection layer on one side and the other side of a highly transparent substrate, and the manufacturing method thereof is, for example, as shown in FIG. First, two types of sheets (sheets 102 and 104) having high transparency and different hardness are formed by an extrusion molding machine, and these are overlapped. At this time, the overlapped sheets have a size that allows a plurality of display window panels as the final form to be obtained, and are referred to as large format substrates 106 here for convenience of explanation.

  Next, as shown in FIG. 9B, hard coat layers 108a and 108b made of ultraviolet (UV) curable resin are formed on both sides of the large substrate 106 by a dip (immersion) molding method.

  Further, as shown in FIG. 9C, the antireflection layers 110a and 110b are formed on the hard coat layers 108a and 108b formed on both surfaces of the large substrate 106 by a dip (immersion) forming method.

  The antireflection layers 110a and 110b are composed of, for example, three layers having different refractive indexes in the order of low, high, and low. In the case of such three layers, dip (immersion) molding is performed three times. By doing so, the antireflection layers 110a and 110b are respectively formed. Moreover, the thermosetting process is made | formed for every shaping | molding of each layer.

  Next, as shown in FIG. 10 (a), water-repellent layers 112a and 112b are formed on the antireflection layers 110a and 110b on both sides by a dip (immersion) molding method, and then as shown in FIG. 10 (b). Then, the water-repellent layer 112b on one side is removed.

  Further, as shown in FIG. 10C, a printing layer 114 is formed by a silk printing method on the antireflection layer 110b on one side where the water-repellent layer 112b on one side is removed by corona discharge and exposed. The large format panel 200 is completed.

  Next, as shown in FIG. 11A, by cutting the large panel 200 into the size of each display window panel 100, a plurality of display window panels 100 as shown in FIG. 11B are obtained. Will be. As described above, the large substrate 106 used as the prior art is composed of two types of sheets (sheets 102 and 104) having different hardnesses, but may be composed of one type of sheet. The manufacturing method in that case is similar to the above-described method.

However, in such a conventional display window panel 100, the antireflection layers 110a and 110b are formed by dipping (immersion), so that the upper and lower antireflection layers 110a and 110b of the display window panel 100 are exactly the same. Both had the same optical characteristics (light transmittance and light reflectance in a predetermined wavelength band).

  In recent years, particularly in the display window panel 100 of an electronic device, a further antireflection effect has been demanded, but the two antireflection layers 110a and 110b have the same optical characteristics, in other words, only one type of optical characteristics. Therefore, it is very difficult to clear the product specifications required for the anti-reflection effect, so it takes a lot of time to select the optimum thickness and material, and in some cases, product development may be delayed. there were.

  Further, development of an antireflection technique using a moth-eye structure is currently in progress. In the conventional formation of the antireflection layers 110a and 110b by dipping (immersion), the display window panel 100 is not only formed on both sides of the display window panel 100. It could not be applied to one side.

  The reason is that the formation of the antireflection layers 110a and 110b by dipping (immersion) cannot prevent the antireflection layers 110a and 110b from being attached on both sides in production, and the moth-eye structure has a minimal pattern (moth eye pattern). However, because of the submicron pattern, the order of the thickness of the dip-molding and the order of the moth-eye pattern are close, covering the moth-eye pattern and depriving the anti-reflection effect of the moth-eye pattern.

  Further, in the above-described conventional manufacturing method, the manufacturing process proceeds in a state where the large-sized substrate 106 that can take a large number of display window panels 100 is used, and the large-sized substrate 106 is dipped (immersed) in a plurality of steps. Since molding is performed, the manufacturing apparatus becomes large and the manufacturing cost increases.

  In view of such a current situation, the present invention has an object to provide a display window panel and a method of manufacturing the display window panel that can easily obtain a desired antireflection effect and can reduce the manufacturing cost. .

The present invention was invented in order to achieve the problems and objects in the prior art as described above,
The display window panel of the present invention is
A display window panel of an electronic device,
The display window panel is
A plate-like substrate having a moth-eye structure minimal pattern formed on one side and having high transparency;
An antireflection sheet adhered to the other surface of the substrate via an adhesive,
It is characterized by comprising at least.

  If configured in this way, the structure is extremely simple, so that the manufacturing is easy and the manufacturing cost can be reduced. Further, since the one surface and the other surface of the substrate are different, a desired antireflection effect can be obtained more easily than before by combining two optical characteristics.

The display window panel of the present invention is
A printed layer is partially formed on a minimal pattern of a moth-eye structure formed on one surface of the substrate.

  If the printing layer is provided in this way, the product can be easily identified by printing, for example, the manufacturer name or product name of the electronic device.

The display window panel of the present invention is
The optical characteristics of one surface of the substrate on which the minimal pattern of the moth-eye structure is formed are different from the optical characteristics of the antireflection sheet attached to the other surface of the substrate.

  If constituted in this way, a desired antireflection effect can be easily obtained by combining two optical characteristics.

The display window panel of the present invention is
The optical characteristic is a light transmittance in a predetermined wavelength band.

  Thus, the light transmittance in a predetermined wavelength band is preferable because it is a clear index for knowing how much the antireflection effect is.

The display window panel of the present invention is
The optical characteristic of the minimal pattern of the moth-eye structure of the substrate is a broad light transmittance in a wavelength band of 450 to 750 nm,
The optical characteristics of the antireflection sheet have a clear light transmittance peak in a wavelength band of 450 to 750 nm.

  If set in this way, a desired antireflection effect can be easily obtained by combining the two optical characteristics.

The display window panel of the present invention is
The optical characteristic is a light reflectance in a predetermined wavelength band.

  Thus, a light reflectance in a predetermined wavelength band is preferable because it is a clear index for knowing how much the antireflection effect is.

The display window panel of the present invention is
The optical characteristics of the minimal pattern of the moth-eye structure of the substrate has no clear light reflectance bottom in the wavelength band of 450 to 750 nm,
And the optical characteristics of the antireflection sheet have a clear bottom of light reflectance in a wavelength band of 450 to 750 nm.

  If set in this way, a desired antireflection effect can be easily obtained by combining the two optical characteristics.

The display window panel of the present invention is
The minimal pattern of the moth-eye structure formed on one surface of the substrate is formed in a convex shape or a concave shape,
It is characterized in that the height (depth) of the convex part or concave part is formed in the range of 100 to 500 nm, the width of the convex part or concave part is in the range of 100 to 500 nm, and the pitch is in the range of 100 to 500 nm. To do.

  Thus, if the minimal pattern of a moth-eye structure is comprised, the refractive index of the thickness direction can be changed continuously and the desired antireflection effect can be acquired.

  In particular, when the minimal pattern of the moth-eye structure is formed in a concave shape, damage to the minimal pattern of the moth-eye structure can be minimized during the manufacturing process.

The display window panel of the present invention is
The antireflection sheet is formed by laminating an antireflection layer, a hard coat layer, and a base material layer.

  Thus, if it consists of three layers, in addition to the function of antireflection, scratch resistance and impact resistance can be added.

The display window panel of the present invention is
The antireflection sheet has water repellency.

  Thus, if it has water repellency, for example, even when a water droplet scatters, wiping is easy, and visibility can be quickly recovered.

The display window panel of the present invention is
The thickness of the pressure-sensitive adhesive material for attaching the antireflection sheet to the other surface of the substrate is in the range of 5 to 20 μm.

  With such a thickness, the antireflection sheet can be stably adhered to the other surface of the substrate, and the scratch resistance can be improved.

The display window panel of the present invention is
The antireflection sheet formed on the other surface of the substrate is disposed on the outermost surface of the display window panel.

  If the antireflection sheet with improved scratch resistance is arranged on the outermost surface of the display window panel, the display window panel can be prevented from being damaged.

In addition, the manufacturing method of the display window panel of the present invention,
A method of manufacturing a display window panel of an electronic device,
The method of manufacturing the display window panel is as follows:
In order to create a plate-like tabbed substrate by injection molding, a step of preparing a mold having a tabbed substrate molding space inside,
A step of attaching a stamper in which a reversal pattern of a minimal pattern of a moth-eye structure is formed on one surface of a board forming space with a tab in the mold,
Injecting molten resin into the mold, and molding a highly transparent plate-like tabbed substrate having a minimal pattern of moth-eye structure formed on one side;
A process of attaching an antireflection sheet to the other surface of the tabbed substrate via an adhesive,
Cutting the tab from the tabbed substrate;
It is characterized by having at least.

  With such a manufacturing method, a moth-eye structure, which is an antireflection structure that was impossible with conventional dip (immersion) molding, can be used on one side. In addition, the display window panel can be obtained with a small number of steps, and the manufacturing apparatus can be reduced in size, so that the manufacturing cost can be suppressed.

In addition, the manufacturing method of the display window panel of the present invention,
After the step of injecting molten resin into the mold and forming a highly transparent plate-like tabbed substrate having a minimal pattern of moth-eye structure formed on one side,
The method further comprises a step of partially forming a printing layer on a minimal pattern having a moth-eye structure formed on one surface of the tabbed substrate.

  If the printing layer is provided in this way, the product identification can be improved by printing, for example, the manufacturer name or product name of the electronic device.

In addition, the manufacturing method of the display window panel of the present invention,
After the step of forming the printed layer, the method further includes a step of applying heat treatment or UV irradiation treatment.

  If heat treatment or UV irradiation treatment is applied in this way, the fixing of the printed layer can be improved.

In addition, the manufacturing method of the display window panel of the present invention,
The antireflection sheet in the step of attaching the antireflection sheet to the substrate with tabs via an adhesive,
The size is larger than the substrate excluding the tab of the tabbed substrate,
After the antireflection sheet is attached to the other surface of the tabbed substrate, the antireflection sheet is cut in accordance with the shape of the substrate.

  If the size of the antireflection sheet is set in this way, the antireflection sheet can be adhered to the entire surface of the substrate without any problem even if there is a slight shift during the attachment to the substrate. Therefore, in order to speed up the manufacture of the display window panel, it is very important to make the size of the antireflection sheet larger than the substrate excluding the tab of the tabbed substrate.

In addition, the manufacturing method of the display window panel of the present invention,
The antireflection sheet has a roll shape.

  By increasing the size of the antireflection sheet as described above, the tolerance margin can be increased with respect to the positional deviation of the antireflection sheet in the step of attaching the antireflection sheet, and the antireflection sheet is large in advance. The process to process into size can be reduced.

In addition, the manufacturing method of the display window panel of the present invention,
A laser is used for cutting the antireflection sheet.

  By using a laser for cutting the antireflection sheet in this way, cutting can be performed in a non-contact manner, residual stress that causes separation of the sheet end face can be reduced, and damage to the sheet surface that is likely to occur due to mechanical cutting is prevented. be able to.

In addition, the manufacturing method of the display window panel of the present invention,
The antireflection sheet is cut in a plurality of times.

  If the antireflection sheet is cut in a plurality of times as described above, the flexibility of the apparatus configuration can be increased and the antireflection sheet can be cut with high accuracy.

In addition, the manufacturing method of the display window panel of the present invention,
After cutting the antireflection sheet,
It is characterized by having a step of determining whether or not the antireflection sheet is accurately cut at a predetermined position by image inspection.

If inspected in this way, there is no fear of shipping a defective product by mistake, so that the reliability of the product can be improved.

In addition, the manufacturing method of the display window panel of the present invention,
After cutting the antireflection sheet,
It is characterized by having a step of removing bubbles by putting the substrate on which the antireflection sheet is adhered into an autoclave.

  If air bubbles are removed in this way, the light transmittance of the display window panel can be further enhanced.

  According to the display window panel of the present invention, the display window panel is bonded to the other surface of the substrate with an adhesive material through a highly transparent plate substrate having a moth-eye structure minimal pattern formed on one surface. The anti-reflective sheet is combined, so it is easy to achieve the desired anti-reflective effect by combining the optical characteristics using the moth-eye structure, which was impossible with conventional dip molding, and the optical characteristics of the anti-reflective sheet. Can get to.

  In addition, according to the method for manufacturing a display window panel of the present invention, a display window panel can be obtained with a small number of steps, and since the dip (immersion) molding is not performed as in the prior art, the manufacturing apparatus can be downsized and the manufacturing cost can be reduced. Can be suppressed.

FIG. 1 is a schematic view for explaining a display window panel according to the present invention. FIG. 2 is a schematic diagram for explaining a minute pattern of the moth-eye structure of the display window panel of the present invention. FIG. 3A is a graph of light transmittance in a predetermined wavelength band, and FIG. 3B is a graph of light reflectance in a predetermined wavelength band. FIG. 4 is a graph of light transmittance and light reflectance in a predetermined wavelength band in Example 1 of the display window panel of the present invention. FIG. 5 is a graph of light transmittance and light reflectance in a predetermined wavelength band in Example 2 of the display window panel of the present invention. FIG. 6 is a process diagram for explaining a method of manufacturing a display window panel according to the present invention. FIG. 7 is a process diagram for explaining a method of manufacturing a display window panel according to the present invention. FIG. 8 is a schematic diagram illustrating a tabbed display window panel. FIG. 9 is a process diagram illustrating a conventional method for manufacturing a display window panel. FIG. 10 is a process diagram for explaining a conventional method of manufacturing a display window panel. FIG. 11 is a process diagram for explaining a conventional method of manufacturing a display window panel.

Hereinafter, embodiments (examples) of the present invention will be described in more detail with reference to the drawings.
The present invention is, for example, a display window panel for an electronic device in which one side and the other side of a synthetic resin substrate are subjected to antireflection treatment, and a method for manufacturing the display window panel.

<Display window panel 10>
As shown in FIG. 1, the display window panel 10 in this embodiment is based on a plate-like substrate 12 having a moth-eye structure minimal pattern 14 formed on one surface and having high transparency. An antireflection sheet 18 is attached to the surface via an adhesive material 16.

  A printed layer 20 is partially formed on the minimal pattern 14 having a moth-eye structure.

  Here, as the material of the substrate 12, a highly transparent synthetic resin can be used, and for example, polycarbonate (PC), polymethyl methacrylate (PMMA), or a cycloolefin polymer is preferably used.

  In addition, about selection of the synthetic resin which has high transparency, what is necessary is just to select suitably according to the specification calculated | required as a product, but 1 mm thickness using the spectrophotometer U-3010 by Hitachi High-Technologies Corporation. In the substrate measurement (wavelength band 400 to 800 nm), a light transmittance of 80% or more is preferable for maintaining good visibility.

  The antireflection sheet 18 adhered to the other surface of the substrate 12 is preferably selected from commercially available products according to the specifications required for the product, for example, an antireflection layer (not shown). A hard coat layer (not shown) and a base material layer (not shown) are laminated, and an AR sheet manufactured by NOF Corporation having an adhesive layer on one side, an AR sheet manufactured by Nippon Kayaku Co., Ltd., etc. Can be used.

  Further, the minimal pattern 14 of the moth-eye structure formed on one surface of the substrate 12 is one in which conical micropores are regularly arranged as shown in FIG. In the range of 500 nm, the width L of the recesses is set in the range of 100 to 500 nm, and the pitch P is set in the range of 100 to 500 nm. Here, the value of H / L is preferably 1 ≦ H / L ≦ 3.

  Such a moth-eye structure is a conventionally known structure having regular conical micropores, and the substrate 12 having such a structure has a continuously changing refractive index in the thickness direction. Even if light hits 12, it has a characteristic of hardly reflecting this light.

  Note that the minimal pattern 14 of the moth-eye structure may be formed in a convex shape. In this case as well, as in the case of the concave portion, the height H of the convex portion is in the range of 100 to 500 nm, and the width L of the convex portion is 100. It is preferable that the pitch P is set within a range of ˜500 nm and a pitch P within a range of 100˜500 nm.

  In such a display window panel 10, the optical characteristics of one surface of the substrate 12 on which the minimal pattern 14 of the moth-eye structure is formed and the optical characteristics of the antireflection sheet 18 attached to the other surface of the substrate 12 are different. It is preferable to set as follows.

  In the present invention, by changing the two optical characteristics of the one surface and the other surface of the substrate 12 and combining the two, the graph of the light transmittance in the predetermined wavelength band shown in FIG. One of the conventional light transmittance curves (A) described is shown as follows: the light transmittance curve (B) of the moth-eye structure on one side of the display window panel 10 of the present invention, and the light rays of the antireflection sheet 18 on the other side. It can be expressed in combination with the transmittance curve (C).

  Further, with respect to one conventional light reflectance curve (a) shown in the graph of light reflectance in a predetermined wavelength band shown in FIG. 3B, the one-side surface of the display window panel 10 of the present invention is also shown. It can be expressed by a combination of the light reflectance curve (b) of the moth-eye structure and the light reflectance curve (c) of the antireflection sheet 18 on the other side.

  For this reason, a desired antireflection effect can be obtained more easily than before.

  The light transmittance and light reflectance required in the predetermined wavelength band are different in curves required by the design concept of the display window panel 10.

  The light transmittance is required to have a broad curve with respect to the set wavelength, but for the light reflectance, when the required color is blue, the bottom wavelength should be set to the longer wavelength side, and when the required color is red Therefore, it is required to be on the short wavelength side.

  In the case of optical characteristics where the bottom wavelength of the light reflectance does not exist, when the required color is blue, the blue wavelength component reflects more than the red wavelength component, and when the required color is red Is required to reflect more of the red wavelength component than the blue wavelength component.

  Therefore, it is preferable to intentionally change the light transmittance and light reflectance in a predetermined wavelength band in both the moth-eye structure minimal pattern 14 and the antireflection sheet 18.

  The antireflection sheet 18 attached to the other surface of the substrate 12 is a laminate of an antireflection layer (not shown), a hard coat layer (not shown), and a base material layer (not shown). It is preferable.

  If configured in this way, in addition to the antireflection function, scratch resistance and impact resistance can be added. In particular, the display window panel 10 such as a digital camera or a mobile phone can be directly touched, or other Even in use in an environment that easily collides with an article, the display window panel 10 can be protected from damage or scratches.

  Further, if the antireflection sheet 18 is provided with water repellency, for example, when water droplets are scattered, it is easy to wipe off, and the visibility can be quickly recovered.

  The water repellent treatment of the antireflective sheet 18 may be performed by mixing a water repellent material with the antireflective sheet or applying a solution obtained by diluting the water repellent material by a conventionally known method.

  In addition, it is preferable to set the thickness of the adhesive 16 which adheres the antireflection sheet 18 to the board | substrate 12 in the range of 5-30 micrometers, and the pencil hardness of the antireflection sheet 18 is 3H-H at this time. The pencil hardness is increased from HB to 3H as the adhesive material 16 is thinner.

  If set in this way, the antireflection sheet 18 can be stably adhered to the substrate 12 and the scratch resistance of the antireflection sheet 18 can be improved, which is preferable.

  As described above, the display window panel 10 of the present invention has a plate-like substrate 12 having a moth-eye structure minimal pattern 14 formed on one surface and having high transparency, and an adhesive 16 attached to the other surface of the substrate 12. Since each of the two surfaces of the antireflection sheet 18 is a structure and a layer capable of obtaining an antireflection effect, a desired antireflection effect can be easily obtained by combining the two optical characteristics. It can be done.

Example 1
As shown in FIG. 1, the display window panel 10 according to the present embodiment uses a plate-like substrate 12 having a moth-eye structure minimal pattern 14 formed on one surface and having high transparency as a base material, and the other side surface of the substrate 12. An antireflective sheet 18 is attached to the substrate via an adhesive material 16. The antireflection sheet 18 has water repellency. In addition, the thickness of the adhesive material 16 which adheres the antireflection sheet 18 to the board | substrate 12 was 10 micrometers, and the pencil hardness of the antireflection sheet 18 in this case was 3H.

  A printed layer 20 is partially formed on the minimal pattern 14 having a moth-eye structure.

  The material of the substrate 12 is PC (polycarbonate).

  The minimal pattern 14 of the moth-eye structure is a pattern in which dents are regularly arranged as shown in FIG. 2, and the dent depth H is in the range of 100 to 500 nm, and the dent width L is in the range of 100 to 500 nm. Of these, the pitch P is in the range of 100 to 500 nm. An AR sheet manufactured by NOF Corporation was used as the antireflection sheet 18.

  Regarding the optical characteristics of the moth-eye structure on one side in this example, as is apparent from the graph of the light transmittance and light reflectance in the predetermined wavelength band shown in FIG. 4, first, the light transmittance is in the wavelength band of 450 to 750 nm. It ’s broad. Moreover, the light reflectance does not have a clear bottom value.

  Regarding the optical characteristics of the antireflection sheet 18 on the other side, the light transmittance has a clear peak in the wavelength band of 450 to 750 nm, and takes a peak value of 97.1% at the wavelength of 564 nm. The light reflectivity takes a bottom value of 1.91% light reflectivity near a wavelength of 550 nm.

  As optical characteristics of the display window panel 10 having the moth-eye structure and the antireflection sheet 18, the light transmittance and light reflectance were measured using a spectrophotometer U-3010 manufactured by Hitachi High-Technologies Corporation.

As a result, the region sandwiching the peak value of the antireflection sheet 18 became a broad curve, and the light transmittance was a peak value of 97.3% of light transmittance at a wavelength of 560 nm.
The light reflectivity was a bottom value of 0.9% in the vicinity of a wavelength of 560 nm.

  Therefore, the optical characteristics of the display window panel 10 obtained by combining the moth-eye structure and the antireflection sheet 18 are substantially the same as the conventional one light transmittance curve and light reflectance curve shown in FIG. It was confirmed that a desired antireflection effect can be obtained by combining the two optical characteristics.

(Example 2)
As shown in FIG. 5, the display window panel 10 in this example has a clear light transmittance peak in the wavelength band of 450 to 750 nm with respect to the antireflection sheet 18 on the other side. Adopting a peak value of 97.7% transmittance, a bottom value having a light reflectance of 0.68% in the vicinity of a wavelength of 590 nm, and sticking the antireflection sheet 18 to the substrate 12 with respect to the light reflectance. Except that the thickness of the material 16 is 25 μm and the pencil hardness of the antireflection sheet 18 in that case is 2H to H, the light transmittance and light reflectance of the display window panel 10 are measured in the same manner as in Example 1. did.

  As a result, a region sandwiching the peak value of the antireflection sheet 18 was a broad curve, and the light transmittance was a peak value of 96.0% when the wavelength was 596 nm.

  Further, the light reflectance was a bottom value with a light reflectance of 1.9% in the vicinity of a wavelength of 555 nm.

Therefore, the optical characteristics of the display window panel 10 obtained by combining the two optical characteristics are:
It was substantially the same as the conventional light transmittance curve and light reflectance curve shown in FIG. 5, and it was confirmed that a desired antireflection effect could be obtained by combining two optical characteristics.

<Method for Manufacturing Display Window Panel 10>
Next, a method for manufacturing the display window panel 10 will be described.
First, as shown in FIG. 6 (a), in order to obtain a plate-like substrate (tabbed substrate 30) with tabs 32 by injection molding, there is a space for molding a substrate with tabs inside, and the upper die 22 is provided. And a lower die 24 are prepared.

  Next, as shown in FIG. 6B, the moth-eye structure minimal pattern is inverted in advance on one side surface of the tab-shaped substrate forming space in the mold 26 (the bottom surface of the lower mold 24 in FIG. 6B). A stamper 28 on which a pattern is formed is mounted.

  The minimal pattern reversal pattern of the moth-eye structure of the stamper 28 is formed by a known technique. For example, powder of about φ100 to 500 nm is arranged on a stamper base material made of a silicon wafer, and in this state. A method of forming a reversal pattern of the minimal pattern of the moth-eye structure by performing a dry etching process on the powder, and forming a fine film having a diameter of about 100 to 500 nm in a vacuum and then performing a dry etching process on the vacuum-formed film A method of forming a reversal pattern of a minimal pattern of a moth-eye structure, a method of forming a reversal pattern of a minimum pattern of a moth-eye structure by an electron beam, a method of forming a reversal pattern of a minimal pattern of a moth-eye structure by laser cutting of a resist Known methods and stampers It can be obtained by application of 28 replication techniques.

  The stamper 28 is preferably formed with a moth-eye structure minimal pattern in a convex shape so that the resin can easily enter a fine pattern by molding.

  In this state, the mold 26 is closed, and as shown in FIG. 6 (c), a highly transparent synthetic resin such as polycarbonate (PC) or polymethyl methacrylate (PMMA) melted in the mold 26 is used. Alternatively, by injecting the cycloolefin polymer, a plate-like tabbed substrate 30 having a high transparency having the moth-eye structure minimal pattern 14 transferred on one surface is obtained.

  The formed tabbed substrate 30 has a shape as shown in FIG. 8, and tabs 32 and 32 are respectively formed on opposite side ends of the substrate 12. The tabs 32 and 32 are locations used for gripping the tabs 32 and 32 and proceeding in the subsequent manufacturing process, and are very important parts for speeding up the manufacturing.

  The positions in the thickness direction of the both ends of the tabs 32 and 32 and the dimensions of the tabs 32 and 32 are determined in accordance with the handling form of the manufacturing apparatus to be used.

  Further, the mold 26 used in the injection molding may be a single-piece type capable of molding one tabbed substrate 30 in one shot, or a multi-piece type obtained in a plurality at a time. is there.

  Next, as shown in FIG. 7A, the tabbed substrate 30 obtained by injection molding in this way has the antireflection sheet 18 attached to the other side via the adhesive material 16. Before sticking the sheet 18, it is preferable to promote the sticking property of the antireflection sheet 18 on the other surface of the tabbed substrate 30 by a known surface treatment method.

  In addition, it is preferable that the antireflection sheet 18 adhered to the other surface of the tabbed substrate 30 after the surface treatment is set to a size larger than the substrate 12. This is because the antireflection sheet 18 is adhered to the entire surface of the substrate 12 even if there is a slight deviation when the antireflection sheet 18 is adhered to the tabbed substrate 30. Further, the antireflection sheet 18 is supplied in a roll shape with a size larger than that of the substrate 12 in order to reduce the number of processes.

After the antireflection sheet 18 is adhered to the tabbed substrate 30, the antireflection sheet 18 is cut using a laser in accordance with the shape of the substrate as shown in FIG. 7B. The laser used can be either a short wavelength laser with an ultraviolet wavelength or a green laser, but a CO ₂ laser is preferred in view of cost performance.

  When the antireflection sheet 18 is cut, it is preferable to first perform rough cutting and then finish cutting. If divided in this way, the antireflection sheet 18 can be cut with high accuracy.

  The number of times may be one time or two times or more, and it is only necessary to be able to cut accurately according to the size of the display window panel 10 which is the final form. It is preferable to set the number of times as appropriate.

  Next, the tabbed substrate 30 to which the antireflection sheet 18 is attached is subjected to image inspection, and it is determined whether or not the sheet is not cut out and the sheet is cut correctly.

  And the board | substrate 30 with a tab which stuck the antireflection sheet | seat 18 considered that there was no problem in this image test | inspection was formed in one side of the board | substrate 30 with a tab next, as shown in FIG.7 (c). A printed layer 20 is partially formed on the minimal pattern 14 having a moth-eye structure. The printing method is not particularly limited, but by using the offset printing method, the silk printing method, the ink jet method and those methods in combination, even a fine design can be surely printed.

  Further, after heat treatment or UV irradiation treatment is performed to fix the printed layer 20, it is placed in an autoclave (not shown) and subjected to high pressure treatment to remove invisible fine bubbles.

  Finally, the tab 32 is cut from the tabbed substrate 30 to complete the display window panel 10 shown in FIG. In addition, when it is required to clean the ridge line portion of the substrate 30 from the viewpoint of appearance quality, the ridge line portion finished by laser cutting may be further finely finished by machining.

  Such a display window panel 10 is packed with a protective sheet (not shown) attached to both sides separately at the time of actual shipment, and shipped in this form.

  As described above, the manufacturing method of the display window panel 10 according to the present invention can obtain the display window panel 10 with a small number of steps, and does not require dip (immersion) molding as in the prior art. Can also be reduced in size and manufacturing costs can be reduced.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this, and various modifications and additions are possible.

DESCRIPTION OF SYMBOLS 10 ... Display window panel 12 ... Board | substrate 14 ... Minimal pattern of a moth-eye structure 16 ... Adhesive material 18 ... Antireflection sheet 20 ... Printed layer 22 ... Upper mold | type 24 ... Lower mold 26 ... Mold 28 ... Stamper 30 ... Substrate with tab 32 ... Tab H ... Depth of recess (height of protrusion)
L: Width of concave part (width of convex part)
P ... Pitch 100 ... Display window panel 102 ... Sheet 104 ... Sheet 106 ... Large substrate 108a..Hard coat layer 108b..Hard coat layer 110a..Antireflection layer 110b..Reflection Prevention layer 112a ... Water repellent layer 112b ... Water repellent layer 114 ... Print layer 200 ... Large format panel

Claims (21)

A display window panel of an electronic device,
The display window panel is
A plate-like substrate having a moth-eye structure minimal pattern formed on one side and having high transparency;
An antireflection sheet adhered to the other surface of the substrate via an adhesive,
A display window panel comprising at least the following.   The display window panel according to claim 1, wherein a printed layer is partially formed on a minimal pattern having a moth-eye structure formed on one surface of the substrate.   The optical characteristic of the one surface in which the minimal pattern of the moth-eye structure of the said board | substrate was formed differs from the optical characteristic of the antireflection sheet affixed on the other surface of the board | substrate. Display window panel.   The display window panel according to claim 3, wherein the optical characteristic is light transmittance in a predetermined wavelength band. The optical characteristic of the minimal pattern of the moth-eye structure of the substrate is a broad light transmittance in a wavelength band of 450 to 750 nm,
5. The display window panel according to claim 4, wherein the optical characteristics of the antireflection sheet have a clear light transmittance peak in a wavelength band of 450 to 750 nm.   The display window panel according to claim 3, wherein the optical characteristic is light reflectance in a predetermined wavelength band. The optical characteristics of the minimal pattern of the moth-eye structure of the substrate has no clear light reflectance bottom in the wavelength band of 450 to 750 nm,
The display window panel according to claim 6, wherein the optical characteristic of the antireflection sheet has a clear bottom of light reflectance in a wavelength band of 450 to 750 nm. The minimal pattern of the moth-eye structure formed on one surface of the substrate is formed in a convex shape or a concave shape,
The height of the convex portion or the depth of the concave portion is in the range of 100 to 500 nm, the width of the convex portion or the concave portion is in the range of 100 to 500 nm, and the pitch is in the range of 100 to 500 nm. The display window panel according to claim 1.   The display window panel according to claim 1, wherein the antireflection sheet is formed by laminating an antireflection layer, a hard coat layer, and a base material layer.   The display window panel according to claim 1, wherein the antireflection sheet has water repellency.   The display window panel according to any one of claims 1 to 10, wherein a thickness of an adhesive material for attaching an antireflection sheet to the other surface of the substrate is in a range of 5 to 20 µm.   The display window panel according to any one of claims 1 to 11, wherein an antireflection sheet formed on the other surface of the substrate is disposed on an outermost surface of the display window panel. A method of manufacturing a display window panel of an electronic device,
The method of manufacturing the display window panel is as follows:
In order to create a plate-like tabbed substrate by injection molding, a step of preparing a mold having a tabbed substrate molding space inside,
A step of attaching a stamper in which a reversal pattern of a minimal pattern of a moth-eye structure is formed on one surface of a board forming space with a tab in the mold,
Injecting molten resin into the mold, and molding a highly transparent plate-like tabbed substrate having a minimal pattern of moth-eye structure formed on one side;
A process of attaching an antireflection sheet to the other surface of the tabbed substrate via an adhesive,
Cutting the tab from the tabbed substrate;
A method for producing a display window panel, comprising: After the step of injecting molten resin into the mold and forming a highly transparent plate-like tabbed substrate having a minimal pattern of moth-eye structure formed on one side,
14. The method for manufacturing a display window panel according to claim 13, further comprising a step of partially forming a printing layer on a minimal pattern of a moth-eye structure formed on one surface of the tabbed substrate.   The method for manufacturing a display window panel according to claim 14, further comprising a step of applying a heat treatment or a UV irradiation treatment after the step of forming the printed layer. The antireflection sheet in the step of attaching the antireflection sheet to the substrate with tabs via an adhesive,
The size is larger than the substrate excluding the tab of the tabbed substrate,
The display window panel according to any one of claims 13 to 15, wherein after the antireflection sheet is attached to the other surface of the tabbed substrate, the antireflection sheet is cut in accordance with the shape of the substrate. Manufacturing method.   The method of manufacturing a display window panel according to claim 16, wherein the antireflection sheet has a roll shape.   The method for manufacturing a display window panel according to claim 16 or 17, wherein a laser is used to cut the antireflection sheet.   The method for manufacturing a display window panel according to any one of claims 16 to 18, wherein the antireflection sheet is cut in a plurality of times. After cutting the antireflection sheet,
20. The method for manufacturing a display window panel according to claim 16, further comprising a step of determining by image inspection whether or not the antireflection sheet is accurately cut at a predetermined position. .   21. The method according to any one of claims 16 to 20, further comprising a step of removing bubbles by placing the substrate on which the antireflection sheet is adhered into an autoclave after the final cutting step on the antireflection sheet. Manufacturing method of display window panel.

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