Airborne imaging device and stack

Abstract

The present application provides an aerial imaging device 10a, 10b, which has a display portion 1, a light transmission imaging portion 3, a light diffusion control portion 2, and an adhesion layer 4, the light transmission imaging portion 3 transmits light from the display portion 1 and images on the side opposite to the display portion 1, the light diffusion control portion 2 diffuses or transmits light incident into the light diffusion control portion 2 according to the incident angle thereof, and has a regular internal structure of a louver shape with a plurality of plate-shaped regions with relatively high refractive index in a region with relatively low refractive index, the adhesion layer 4 is composed of any one of an adhesive, an adhesive agent, and an adhesive adhesive agent, and the amount of acidic groups present in the adhesion layer 4 is 0.050 mmol / g or less with respect to all components constituting the adhesion layer 4. The aerial imaging device 10a, 10b has excellent durability and can well observe aerial images.

Description

Technical Field

[0001] The present invention relates to an aerial imaging device and a laminate for forming the aerial imaging device. Background Technology

[0002] Aerial images are images formed by reflecting and refracting light emitted from a light source through optical elements, creating an image at any location in space. When aerial images are displayed without a screen or monitor, viewers experience a unique and often unsettling feeling. Therefore, aerial images have been increasingly used in various applications, including virtual reality, in recent years.

[0003] For example, Patent Document 1 discloses an aerial imaging device, which is an aerial imaging device having at least a display unit and a light-transmitting imaging unit. The image (real image) displayed by the display unit is displayed as an aerial image mainly through the function of the light-transmitting imaging unit. Existing technical documents Patent documents

[0004] Patent Document 1: Japanese Patent Application Publication No. 2020-060752 Summary of the Invention (a) Technical problems to be solved

[0005] When aerial imaging devices are activated, sometimes an unexpected image, known as a ghost image, may appear simultaneously with the aerial image. Ghost images are unintended and do not accurately reflect the true image. Furthermore, ghost images may overlap with the aerial image, making it difficult to properly visualize the aerial image.

[0006] From the perspective of suppressing the occurrence of ghosting, the inventors of this application have discovered that by providing a light diffusion control unit in an aerial imaging device that diffuses or transmits light according to the incident angle, the occurrence of ghosting can be effectively suppressed. Specifically, it has been found that by providing the aforementioned light diffusion control unit on the display side surface of the light-transmitting imaging unit, the occurrence of ghosting can be effectively suppressed.

[0007] Furthermore, in aerial imaging devices, interference light caused by external light sources can sometimes be perceived simultaneously with the aerial image. For example, when an aerial imaging device is placed under a fluorescent lamp, the viewer may perceive interference light corresponding to that fluorescent lamp, thus hindering the perception of the aerial image.

[0008] Here, the interfering light is not merely surface reflection from the translucent imaging element, but rather light that penetrates into the translucent imaging element and returns to the observer's side. Since diffraction is accompanied by color distortion, visibility is significantly reduced compared to the reflection from a typical external light source.

[0009] Since it is also envisioned that the aerial imaging device will be used in places with many external light sources, such as convenience stores, it is necessary to suppress the effects of the aforementioned interfering light.

[0010] The inventors of this application have discovered that the aforementioned light diffusion control unit is effective from the perspective of suppressing the generation of interfering light. That is, it has been found that by providing the aforementioned light diffusion control unit on the surface of the light-transmitting imaging unit opposite to the display unit, the generation of interfering light can be effectively suppressed.

[0011] However, the inventors of this application have discovered that, as described above, when a laminate formed by stacking a light diffusion control unit onto any surface of the light-transmitting imaging unit is placed in a high-temperature environment or a high-temperature and high-humidity environment, air bubbles easily form between the light-transmitting imaging unit and the light diffusion control unit. The formation of such air bubbles is a major cause of impaired visibility of aerial images.

[0012] The present invention was made in view of the actual situation, and its object is to provide an aerial imaging device with excellent durability and good visibility of aerial images, as well as a stack for forming the aerial imaging device. (II) Technical Solution

[0013] To achieve the above objectives, firstly, the present invention provides an aerial imaging device, characterized in that it comprises: a display unit having a display surface from which light is emitted; a light-transmitting imaging unit disposed on the display surface side of the display unit; a light diffusion control unit stacked on the side of the light-transmitting imaging unit opposite to the display unit or stacked on the side of the light-transmitting imaging unit on the display unit side; and a sealing layer stacked between the light-transmitting imaging unit and the light diffusion control unit to seal the light-transmitting imaging unit and the light diffusion control unit, wherein the light-transmitting imaging unit... The light transmitted from the display surface is imaged at a position opposite to the display section. The light diffusion control section diffuses or transmits light incident on the light diffusion control section according to its incident angle, and has a regular internal structure in the form of louvers with multiple plate-shaped regions with relatively high refractive index in regions with relatively low refractive index. The adhesive layer is composed of any one of adhesive, bonding agent, and adhesive bonding agent, and the amount of acidic groups present in the adhesive layer is less than 0.050 mmol / g relative to all components constituting the adhesive layer. (Invention 1)

[0014] In the above invention (Invention 1), it is preferable that the amount of hydroxyl groups present in the adhesive layer is 0.2 mmol / g or more and 20.0 mol / g or less relative to all the components constituting the adhesive layer (Invention 2).

[0015] In the above inventions (Inventions 1 and 2), it is preferred that the hydroxyl value of the component constituting the adhesive layer is 10 mg KOH / g or more and 500 mg KOH / g or less, and the acid value of the component constituting the adhesive layer is 0 mg KOH / g or more and 3.0 mg KOH / g or less (Invention 3).

[0016] In the above inventions (Inventions 1 to 3), preferably, the total light transmittance of the sealing layer is 80% or more (Invention 4).

[0017] In the above inventions (Inventions 1 to 4), it is preferable to arrange the display unit in such a way that the display surface is not parallel to the surface of the light diffusion control unit opposite to the light-transmitting imaging unit (Invention 5).

[0018] In the above inventions (Inventions 1 to 5), it is preferable that when the direction perpendicular to the long side direction of the plate-shaped region and existing in the plane opposite to the light-transmitting imaging region of the light diffusion control section is set as the first direction, each of the plate-shaped regions is inclined in the first direction within the light diffusion control section (Invention 6).

[0019] In the above inventions (Inventions 1 to 6), it is preferable that the light-transmitting imaging unit includes a retro-transmitting optical element that transmits incident light in the reverse direction (Invention 7).

[0020] In the above invention (Invention 7), it is preferable that the retrotransmission optical element is formed by two layers having multiple reflective surfaces, wherein in each of the two layers, the multiple reflective surfaces are arranged in a manner perpendicular to one surface of the retrotransmission optical element and at a predetermined interval from each other, and the two layers are stacked in such a manner that the reflective surface of one layer is orthogonal to the reflective surface of the other layer (Invention 8).

[0021] Second, the present invention provides a laminate, characterized in that it comprises: a light-transmitting imaging section that images light incident from one side at a position on the other side; a light diffusion control section laminated on one side of the light-transmitting imaging section; and an adhesive layer laminated between the light-transmitting imaging section and the light diffusion control section, thereby sealing the light-transmitting imaging section and the light diffusion control section, wherein the light diffusion control section diffuses or transmits light incident into the light diffusion control section according to its incident angle, and has a regular internal structure in the form of louvers with a plurality of plate-shaped regions with relatively high refractive index in regions with relatively low refractive index, the adhesive layer being composed of any one of an adhesive, a binder, and an adhesive bonding agent, and the amount of acidic groups present in the adhesive layer is 0.050 mmol / g or less relative to all components constituting the adhesive layer. (Invention 9) (III) Beneficial Effects

[0022] The aerial imaging device of the present invention exhibits excellent durability and is capable of effectively viewing aerial images. Furthermore, the above-described aerial imaging device can be formed using the laminated body according to the present invention. Attached Figure Description

[0023] Figure 1 A cross-sectional view is shown schematically as an example of an aerial imaging apparatus according to one embodiment of the present invention. Figure 2 A cross-sectional view is shown schematically as an example of an aerial imaging apparatus according to another embodiment of the present invention. Figure 3 A three-dimensional view schematically showing the internal structure of the light diffusion control film. Figure 4 A diagram illustrating the relationship between the optical characteristics of the light diffusion control unit and the light that forms aerial images and ghosting. Figure 5 This is a photograph of the stacked body taken in Experiment Example 2. Figure 6 This is a photograph of the stacked body taken in Experiment Example 2. Figure 7 This is a photograph of the stacked body taken in Experiment Example 2. Detailed Implementation

[0024] The following describes the embodiments of the present invention. [Aerial Imaging Device] Figure 1 A cross-sectional view is shown schematically as an example of an aerial imaging apparatus according to this embodiment. Furthermore, Figure 2 This is a cross-sectional view illustrating an example of an aerial imaging device according to another embodiment.

[0025] like Figure 1 and Figure 2 As shown, the aerial imaging devices 10a and 10b of this embodiment include: a display unit 1 having a display surface from which light is emitted; a light-transmitting imaging unit 3 disposed on the display surface side of the display unit 1; a light diffusion control unit 2 stacked on one or both of the side of the light-transmitting imaging unit 3 opposite to the display unit 1 or the side of the light-transmitting imaging unit 3 opposite to the display unit 1; and a sealing layer 4 stacked between the light-transmitting imaging unit 3 and the light diffusion control unit 2, thereby sealing the light-transmitting imaging unit 3 and the light diffusion control unit 2.

[0026] In particular, Figure 1 In the aerial imaging device 10a shown, the light diffusion control unit 2 is stacked on one side of the display unit 1 of the light-transmitting imaging unit 3. Furthermore, in Figure 2In the aerial imaging device 10b shown, the light diffusion control unit 2 is configured to be stacked on the side opposite to the display unit 1 of the light-transmitting imaging unit 3.

[0027] Furthermore, the light-transmitting imaging unit 3 transmits light from the aforementioned display surface, forming an image on the side opposite to the display unit 1. Additionally, the light diffusion control unit 2 diffuses or transmits light incident upon it according to its angle of incidence, and has a regular internal structure resembling louvers with multiple plate-like regions having relatively high refractive index in regions with relatively low refractive index. Further, the sealing layer 4 is composed of any one of an adhesive, a binder, and an adhesive-adhesive mixture, and the amount of acidic groups present in the sealing layer 4 is 0.050 mmol / g or less relative to all components constituting the sealing layer 4.

[0028] 1. Effect (1) Suppress the occurrence of ghosting In the aerial imaging device 10a, which is configured as a light diffusion control unit 2 stacked on one side of the display unit 1 of the light-transmitting imaging unit 3 ( Figure 1 This technology can effectively suppress ghosting. The following explains its effectiveness.

[0029] Figure 3 A perspective view schematically illustrating the internal structure of the light diffusion control unit 2 is shown. (For example...) Figure 3 As shown, the light diffusion control unit 2 has a regular internal structure resembling louvers, and it has multiple plate-shaped regions 201 with relatively high refractive indices in the region 202 with relatively low refractive indices. By having this regular internal structure, the light diffusion control unit 2 can strongly diffuse incident light that is incident on the surface of the light diffusion control unit 2 within a predetermined incident angle range, while simultaneously emitting it out at a predetermined opening angle. On the other hand, when light is incident outside the aforementioned incident angle range, the light may be transmitted without diffusion, or emitted with a weaker diffusion than when the incident light is within the incident angle range. Furthermore, the direction perpendicular to the long side direction of the plate-shaped regions 201 and existing in the plane of the light diffusion control unit 2 opposite to the light-transmitting imaging unit 3 (…) Figure 3 The direction indicated by "D1" is set as the "first direction".

[0030] The aerial imaging device 10a of this embodiment, when displaying the desired image on the surface of the display unit 1, can, when viewed from the designated observation point 6, display a clear and vivid image. Figure 1 The location indicated by the symbol "5" is where the image formed by the above-mentioned real image in the air is viewed (aerial image). In addition, in this specification, the surface at the location indicated by the symbol "5" is referred to as the "aerial image observation surface".

[0031] In conventional aerial imaging devices, aerial images are sometimes displayed alongside images known as ghosting. Ghosting refers to images that, although not displayed on the display surface of display unit 1, appear around the aerial image on the aerial image viewing surface 5, reflecting the displayed image. To suppress the occurrence of such ghosting, optical elements that only block light that contributes to the formation of ghosting are sometimes used. However, since these optical elements block a portion of the light emitted from display unit 1, the brightness of the aerial image is reduced, making it difficult for viewers to see the aerial image.

[0032] In response, the aerial imaging device 10a of this embodiment, by providing a light diffusion control unit 2, can effectively suppress ghosting while maintaining sufficient brightness in the aerial image. This effect, as explained below, is presumed to be caused by the action of the light diffusion control unit 2. However, it is not limited to this effect, and the possibility of other effects is not excluded.

[0033] Figure 4 The diagram illustrates the effect of the light diffusion control unit 2, and in particular, the relationship between the optical characteristics of the light diffusion control unit 2 and the light that forms aerial images and ghosting.

[0034] As described above, the light diffusion control unit 2 diffuses and transmits light incident within a specified incident angle range, while light incident outside this incident angle range is transmitted with almost no diffusion. Figure 4 The graph illustrates the relationship between the incident angle of light incident on the light diffusion control unit 2 and the haze value. Specifically, for light incident from an incident angle range of approximately -10° to approximately 10°, a haze value greater than 80% is displayed (i.e., the light is diffused and transmitted). On the other hand, for light incident from an incident angle range of approximately -70° to approximately -20°, a haze value of approximately 15% is displayed (i.e., the light is transmitted with almost no diffusion). Additionally, sometimes the incident angle varies significantly in haze value (…). Figure 4 In the meantime (around -15°), this is called the "threshold".

[0035] The aforementioned "haze value" differs from the usual "haze." It refers to the measured value obtained by changing the incident angle of the sample at a specified distance between the integrating sphere opening and the sample. In the measurement of this specification, the specified distance is set to 20 mm, but this value is not particularly limited as long as the value of direct transmission / diffusion transmission of the incident light can be confirmed.

[0036] The aerial imaging device 10a of this embodiment, by having a light diffusion control unit 2 displaying the aforementioned optical characteristics located between the display unit 1 and the light-transmitting imaging unit 3, allows light used to form an aerial image to reach the light-transmitting imaging unit 3 effectively, while light used to form ghosting reaches the light-transmitting imaging unit 3 in a diffused state. Therefore, the viewer can clearly see the aerial image while minimizing the appearance of ghosting. Furthermore, since the light diffusion control unit 2 not only blocks light but also controls its diffusion, it can suppress ghosting while displaying the aerial image with sufficient brightness.

[0037] In addition, the type of light diffusion control unit 2 and its stacking state with the light-transmitting imaging unit 3 can be adjusted appropriately, such as... Figure 4 As shown, better results can be achieved by adjusting the threshold to fall between the incident angle range of the light used to form aerial images and the incident angle range of the light used to form ghosting.

[0038] (2) Suppression of the effects of interfering light Furthermore, in the aerial imaging device 10b, where the light diffusion control unit 2 is stacked on the side opposite to the display unit 1 of the light-transmitting imaging unit 3 ( Figure 2 This can effectively suppress the influence of interfering light. The effect is explained below.

[0039] The inventors of this application conducted various studies and concluded that the aforementioned interference light is caused by light from an external light source incident on the light-transmitting imaging unit 3, which returns to the viewer's direction (hereinafter sometimes referred to as "return light"). It is speculated that such return light is as follows: particularly when the light-transmitting imaging unit is a retrograde optical element described later, light from an external light source incident on the interior of the retrograde optical element undergoes a significant change in its emission direction within the retrograde optical element and exits from the viewer's side.

[0040] The aerial imaging device 10b of this embodiment, by providing a light diffusion control unit 2 on the viewer-side surface of the light-transmitting imaging unit 3, allows light incident from an external light source to the light-transmitting imaging unit 3 to be diffused and transmitted through the light diffusion control unit 2. This allows for the blurring of reflected light while suppressing color distortion, thus improving visibility. Furthermore, for light from the display unit 1, the direct transmission light diffusion control unit 2 enables a clear display of the aerial image. These results in the aerial imaging device 10b of this embodiment, where reflected light and interference light are suppressed, leading to excellent visibility of the aerial image.

[0041] (3) Durability The aerial imaging devices 10a and 10b of this embodiment have excellent durability because the sealing layer 4 exists between the light diffusion control unit 2 and the light-transmitting imaging unit 3.

[0042] In conventional aerial imaging devices, the light diffusion control unit, the light transmission imaging unit, and other components are often fixed together with a conventional adhesive layer. In such cases, when the aerial imaging device is placed in a high-temperature environment or a high-temperature and high-humidity environment for an extended period, a large number of bubbles may form in the laminated structure composed of the light diffusion control unit and the light transmission imaging unit. In aerial imaging devices that generate such bubbles, the visibility of aerial images is significantly reduced. The inventors of this application believe that such bubbles originate from gases generated from the light transmission imaging unit when placed in a high-temperature environment.

[0043] Furthermore, the aerial imaging devices 10a and 10b of this embodiment, by utilizing a sealing layer 4 that satisfies the aforementioned conditions regarding the amount of acidic groups to fix at least the light diffusion control unit 2 and the light-transmitting imaging unit 3, can suppress the generation of gas from the light-transmitting imaging unit even when placed in a high-temperature environment or a high-temperature and high-humidity environment for a long time, thereby suppressing the generation of bubbles. As a result, the aerial imaging devices 10a and 10b of this embodiment can maintain excellent visibility.

[0044] 2. Display Unit The display unit 1 constituting the aerial imaging devices 10a and 10b of this embodiment is not particularly limited as long as it has a display surface and displays an image on that surface, and can emit light to the light diffusion control unit 2 and the light-transmitting imaging unit 3. For example, a liquid crystal display (LCD), a light-emitting diode (LED) display, an organic electroluminescent (organic EL) display, etc., can be used as the display unit 1.

[0045] Furthermore, the positional relationship between the display unit 1, the light diffusion control unit 2, the light-transmitting imaging unit 3, and the sealing layer 4 is not particularly limited. Figure 1 and Figure 2 As shown, the display unit 1 is preferably sufficiently isolated from the light diffusion control unit 2, etc., with a space between them. Furthermore, it is preferable to arrange the display unit 1 such that the display surface of the display surface 1 is not parallel to the surface of the light diffusion control unit 2 opposite to the light-transmitting imaging unit 3, and the sealing part 4. This positional relationship allows for better display of aerial images.

[0046] 3. Light diffusion control unit The light diffusion control unit 2 of the aerial imaging devices 10a and 10b constituting this embodiment is not particularly limited as long as it has the above-mentioned regular internal structure in the shape of louvers.

[0047] From the perspective of easily forming the aforementioned internal structure, the light diffusion control unit 2 is preferably formed by curing a light diffusion control unit containing a high refractive index component and a low refractive index component having a lower refractive index than the high refractive index component with a composition. It is particularly preferred that the high refractive index component and the low refractive index component each have one or two polymerizable functional groups.

[0048] Furthermore, from the perspective of SDGs, the materials used to construct the light diffusion control unit 2 can be materials with high biomass content, materials that can be recycled or reused, or materials that have been recycled or reused.

[0049] (1) High refractive index components Preferred examples of high-refractive-index components include (meth)acrylates containing aromatic rings, and particularly preferred are (meth)acrylates containing multiple aromatic rings. Examples of (meth)acrylates containing multiple aromatic rings include biphenyl (meth)acrylate, naphthyl (meth)acrylate, anthracene (meth)acrylate, benzylidene (meth)acrylate, biphenyloxyalkyl (meth)acrylate, naphthoxyalkyl (meth)acrylate, anthraceneoxyalkyl (meth)acrylate, and benzylidene phenoxyalkyl (meth)acrylate, etc., where a portion of these groups is replaced by halogens, alkyl groups, alkoxy groups, haloalkyl groups, etc. Among these, biphenyl (meth)acrylate is preferred from the perspective of easily forming a good, regular internal structure; specifically, o-phenylphenoxyethyl acrylate and o-phenylphenoxyethoxyethyl acrylate are preferred. Furthermore, in this specification, (meth)acrylate refers to both acrylic acid and methacrylic acid. Other similar terms are also used.

[0050] The molecular weight of the high refractive index component is preferably 150 to 2500, particularly preferably 200 to 1500, and even more preferably 250 to 1000. This facilitates the formation of a light diffusion control section 2 with a desired regular internal structure. Furthermore, when the theoretical molecular weight of the high refractive index component can be determined based on its molecular structure, the molecular weight of the high refractive index component refers to that theoretical molecular weight. On the other hand, when the high refractive index component is, for example, a polymer component, and it is difficult to determine the theoretical molecular weight, the molecular weight of the high refractive index component refers to the weight-average molecular weight obtained as a value converted from standard polystyrene determined by gel permeation chromatography (GPC). Additionally, the method for determining the weight-average molecular weight in this specification refers to the value converted from standard polystyrene determined by this GPC method.

[0051] The refractive index of the high-refractive-index component is preferably 1.45 to 1.70, more preferably 1.50 to 1.65, particularly preferably 1.54 to 1.62, and even more preferably 1.56 to 1.59. This facilitates the formation of the light diffusion control section 2 with the desired regular internal structure. Furthermore, the refractive index in this specification refers to the refractive index of the specified component before the light diffusion control section is cured with the composition, and this refractive index is measured based on JIS K0062:1992.

[0052] The content of the high refractive index component in the composition for the light diffusion control section is preferably 25 to 400 parts by mass relative to 100 parts by mass of the low refractive index component, more preferably 50 to 350 parts by mass, particularly preferably 75 to 300 parts by mass, and even more preferably 100 to 200 parts by mass. Thus, in the regular internal structure of the formed light diffusion control section 2, the regions from the high refractive index component and the regions from the low refractive index component exist in a desired ratio, making it easier to form the desired regular internal structure.

[0053] (2) Low refractive index components Preferred examples of low refractive index components include urethane (meth)acrylates, (meth)acrylate polymers having (meth)acryloyl groups in their side chains, silicone resins containing (meth)acryloyl groups, and unsaturated polyester resins. Among these, urethane (meth)acrylates are particularly preferred from the perspective of easily forming a well-defined, regular internal structure. More specifically, urethane (meth)acrylates formed from (a) a compound containing at least two isocyanate groups, (b) a polyalkyl glycol, and (c) a hydroxyalkyl (meth)acrylate are preferred.

[0054] Preferred examples of compounds containing at least two isocyanate groups as described in (a) above include aromatic polyisocyanates such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,3-phenylenedimethylene diisocyanate, and 1,4-phenylenedimethylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate; and biuret forms and isocyanurate forms of these polyisocyanates, as well as adducts of reactants with low molecular weight compounds containing active hydrogen such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. Alicyclic polyisocyanates are preferred, and alicyclic diisocyanates are particularly preferred.

[0055] Preferred examples of the polyalkyl glycol in (b) above include polyethylene glycol, polypropylene glycol, polybutane glycol, and polyhexane glycol, with polypropylene glycol being the most preferred. Furthermore, the weight-average molecular weight of the polyalkyl glycol in (b) is preferably 2300 to 19500, particularly preferably 3000 to 14300, and even more preferably 4000 to 12300.

[0056] Preferred examples of the above-mentioned (c)hydroxyalkyl (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, among which 2-hydroxyethyl (meth)acrylate is preferred.

[0057] The synthesis of urethane (meth)acrylates using the components (a) to (c) above as materials can be carried out according to conventional methods. In this case, from the perspective of efficiently synthesizing urethane (meth)acrylates, the blending ratio of components (a) to (c) is preferably set to a molar ratio of (a) component:(b) component:(c) component = 1 to 5:1:1 to 5, and particularly preferably a ratio of 1 to 3:1:1 to 3.

[0058] The weight-average molecular weight of the low-refractive-index component is preferably 3,000 to 20,000, particularly preferably 5,000 to 15,000, and even more preferably 7,000 to 13,000. This facilitates the formation of the light diffusion control section 2 with the desired regular internal structure.

[0059] The refractive index of the low-refractive-index component is preferably 1.30 to 1.59, more preferably 1.38 to 1.50, particularly preferably 1.42 to 1.49, and even more preferably 1.46 to 1.48 or less. This facilitates the formation of the light diffusion control section 2 with the desired regular internal structure.

[0060] (3) Other additives The composition for the light diffusion control section described above may contain other additives in addition to high-refractive-index and low-refractive-index components. Examples of other additives include multifunctional monomers, photopolymerization initiators, antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, polymerization accelerators, polymerization inhibitors, infrared absorbers, oxygen absorbers, plasticizers, diluents, and leveling agents.

[0061] In the above description, the composition for the light diffusion control section preferably contains a photopolymerization initiator. This allows for the easy and efficient formation of the light diffusion control section 2, which has the desired regular internal structure.

[0062] Examples of photopolymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl-propane-1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy... The ingredients include 2-propyl ketone, benzophenone, p-phenylbenzophenone, 4,4-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylaminobenzoate, and oligomeric [2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propane]. These ingredients can be used alone or in combination of two or more.

[0063] When a photopolymerization initiator is used, the content of the photopolymerization initiator in the composition for the light diffusion control section is preferably 0.2 to 20 parts by mass, more preferably 0.5 to 16 parts by mass, particularly preferably 1 to 13 parts by mass, and even more preferably 4 to 10 parts by mass, relative to 100 parts by mass of the high-refractive-index component and the low-refractive-index component. This allows for the easy and effective formation of the light diffusion control section 2 with the desired regular internal structure.

[0064] (4) Preparation of the composition for the light diffusion control section The composition for light diffusion control can be prepared by uniformly mixing the above-mentioned high refractive index component and low refractive index component, as well as other additives such as photopolymerization initiators and ultraviolet absorbers as needed.

[0065] During the above mixing process, the mixture can be heated to a temperature of 40-80°C while stirring to obtain a uniform composition for light diffusion control. Furthermore, a diluent can be added to adjust the viscosity of the resulting composition for light diffusion control to the desired level.

[0066] (5) Internal structure of the rule As described above, the light diffusion control unit 2 preferably has a regular internal structure in the shape of a louver, having multiple plate-shaped regions 201 with relatively high refractive index in a region 202 with relatively low refractive index.

[0067] In the light diffusion control unit 2, such as Figure 3As shown, each of the preferred plate-shaped regions 201 is inclined in the first direction D1 within the light diffusion control unit 2. Therefore, the aerial imaging device 10 of this embodiment can easily suppress ghosting or interference light, while also displaying aerial images more brightly.

[0068] When the plate-shaped region 201 is tilted as described above, the tilt angle relative to the thickness direction of the light diffusion control unit 2 is preferably 0° to 30°, more preferably 1° to 20°, particularly preferably 2° to 15°, and even more preferably 3° to 10°. Therefore, the aerial imaging device 10 of this embodiment easily suppresses ghosting or interference light, and at the same time easily displays aerial images more brightly.

[0069] The light diffusion control unit 2 may also have other functions such as... Figure 3 Structures other than the regular internal structure shown. For example, the plate-shaped region 201 may also be bent midway in the thickness direction of the light diffusion control section 2. Furthermore, the light diffusion control section 2 may be composed of two or more layers of plate-shaped regions 201 arranged in a regular internal structure.

[0070] (6) Thickness of the light diffusion control section The thickness of the light diffusion control section 2 is preferably 1 to 500 μm, more preferably 10 to 300 μm, particularly preferably 50 to 250 μm, and even more preferably 80 to 200 μm. Therefore, the aerial imaging device 10 of this embodiment easily suppresses ghosting or interfering light, and at the same time easily displays aerial images more brightly.

[0071] (7) Method for forming the light diffusion control section There are no particular limitations on the method for forming the light diffusion control unit 2, and it can be formed by conventionally known methods.

[0072] For example, the light diffusion control composition is coated onto one side of an engineering sheet to form a coating film. Then, a release liner (particularly the release liner side) is attached to the side of the coating film opposite to the engineering sheet. Next, the coating film can be cured by irradiating it with active energy rays through the engineering sheet or the release liner, thus forming the light diffusion control section 2. In this way, by stacking the release liner on the coating film, maintaining the gap between the release liner and the engineering sheet, and suppressing pressure damage to the coating film, it is easy to form the light diffusion control section 2 with a uniform thickness and a desired regular internal structure.

[0073] As the release sheet mentioned above, resin films such as polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene-(meth)acrylate copolymer film, ethylene-(meth)acrylate copolymer film, polystyrene film, polycarbonate film, polyimide film, and fluoropolymer film can be used. Furthermore, cross-linked films of these films can also be used. Further, laminated films of these films can also be used. In addition, from the perspective of SDGs, materials with high biomass content, recyclable or reusable materials, and materials that have been recycled or reused can be used as the materials constituting the release sheet.

[0074] Preferably, the release surface of the release sheet is subjected to a release treatment. Examples of release agents used in the release treatment include alkyd-based, silicone-based, fluorinated, unsaturated polyester-based, polyolefin-based, and wax-based release agents.

[0075] There is no particular limitation on the thickness of the release sheet, but from the perspective of excellent operability and good protection of the light diffusion control part before use, it is preferably 20~200μm, more preferably 30~100μm.

[0076] As the aforementioned engineering sheet, the resin film, cross-linked film, or laminate of these films used as release sheets can be used. Alternatively, the aforementioned release sheet can also be used as an engineering sheet.

[0077] From the perspective of easily forming the desired light diffusion control section and ensuring good protection of the light diffusion control section before use, the thickness of the engineering sheet is preferably 20~250μm, more preferably 30~200μm.

[0078] Examples of coating methods include blade coating, roller coating, bar coating, squeegee coating, die coating, and gravure coating. Furthermore, the composition for the light diffusion control section can be diluted with a solvent as needed.

[0079] Irradiating the coating with active energy rays can be done using methods known in the art. For example, a linear light source can be used as the light source for the active energy rays, irradiating the surface of the object with a strip-shaped (approximately linear) beam that is random in the width direction (TD direction) and approximately parallel in the flow direction (MD direction). Alternatively, the tilt angle of the plate-shaped region 201 can be adjusted by adjusting the irradiation angle of the aforementioned beam.

[0080] Furthermore, the aforementioned active energy rays refer to rays that possess energy quanta within electromagnetic waves or charged particle beams; specifically, examples include ultraviolet light and electron beams. Among active energy rays, ultraviolet light is preferred as it is easy to manipulate and readily forms the desired regular internal structure.

[0081] When using ultraviolet light as an active energy ray, the peak irradiance of the coating surface is preferably set to 0.1~200 mW / cm² as the irradiation condition. 2 Furthermore, the cumulative light intensity on the coating surface is preferably set to 5~300 mJ / cm. 2 Furthermore, the relative moving speed of the light source of the active energy rays to the irradiated object is preferably set to 0.1~10 m / min.

[0082] Furthermore, from the perspective of achieving more thorough curing, after curing with the strip light as described above, it is preferable to irradiate with ordinary active energy rays (active energy rays that are not converted into parallel light or strip light, or scattered light).

[0083] 4. Light-transmitting imaging unit The light-transmitting imaging unit 3 constituting the aerial imaging devices 10a and 10b of this embodiment is not particularly limited as long as it can transmit light from the display unit 1 and image an aerial image on a predetermined aerial image observation surface. Examples of such a light-transmitting imaging unit 3 include retro-transmitting optical elements that transmit incident light in the reverse direction.

[0084] While conventionally known retrotransmission optical elements can be used as the aforementioned retrotransmission optical elements, from the perspective of easily and effectively imaging aerial images, a retrotransmission optical element with a two-sided orthogonal reflector array structure or a two-sided corner reflector array structure is preferred, and a retrotransmission optical element with a two-sided orthogonal reflector array structure is more preferred. For example, the configuration described in Japanese Patent No. 5085631 can be cited as an example of a retrotransmission optical element with a two-sided orthogonal reflector array structure. That is, as a retrotransmission optical element with a two-sided orthogonal reflector array structure, it is preferable to use a retrotransmission optical element formed by stacking two layers having multiple reflective surfaces. In particular, in this retrotransmission optical element, in each of the two layers, it is preferable that the multiple reflective surfaces are arranged perpendicular to one surface of the retrotransmission optical element and at predetermined intervals, and that the two layers are stacked such that the reflective surface of one layer is orthogonal to the reflective surface of the other layer. As a retrotransmitting optical element with a dihedral reflector array structure, specifically, the configuration described in international publication WO2007 / 116639 can be used.

[0085] The thickness of the light-transmitting imaging part 3 is preferably 0.1 to 20 mm, more preferably 0.5 to 15 mm, particularly preferably 1 to 12 mm, further preferably 2 to 10 mm, and most preferably 4 to 8 mm. Therefore, the aerial imaging devices 10a and 10b of this embodiment can easily suppress ghosting or interference light, and can also easily display aerial images more brightly.

[0086] 5. Sealing layer The specific details of the sealing layer 4 in this embodiment are not particularly limited as long as it is composed of any one of adhesive, bonding agent and adhesive bonding agent, and the amount of acidic groups present in the sealing layer 4 is less than 0.050 mmol / g relative to all the components constituting the sealing layer 4.

[0087] From the perspective of effectively suppressing the generation of bubbles, the amount of the above-mentioned acidic groups is preferably 0.040 mmol / g or less, more preferably 0.030 mmol / g or less, particularly preferably 0.020 mmol / g or less, further preferably 0.010 mmol / g or less, more preferably 0.001 mmol / g or less, and the most preferred lower limit is 0 mmol / g.

[0088] Furthermore, from the perspective of effectively suppressing the generation of bubbles, the amount of hydroxyl groups present in the sealing layer 4 is preferably 0.2 to 20.0 mmol / g, particularly preferably 0.3 to 10.0 mmol / g, and even more preferably 0.4 to 5.0 mmol / g, relative to all the components constituting the sealing layer 4.

[0089] The amounts of acidic groups and hydroxyl groups in this specification are theoretical values ​​derived from the components constituting the sealing layer.

[0090] Furthermore, from the perspective of easily achieving the above-mentioned amount of acidic groups, the hydroxyl value of the component constituting the close-knit layer 4 is preferably 10~500mgKOH / g, preferably 30~350mgKOH / g or more, particularly preferably 50~200mgKOH / g, further preferably 60~150mgKOH / g, and preferably 70~120mgKOH / g.

[0091] Furthermore, from the perspective of easily achieving the above-mentioned amount of acidic groups, the acid value of the components constituting the sealing layer 4 is preferably 3.0 mg KOH / g or less, more preferably 2.5 mg KOH / g or less, particularly preferably 2.0 mg KOH / g or less, further preferably 1.0 mg KOH / g or less, wherein, preferably 0.1 mg KOH / g or less, and the most preferred lower limit is 0 mg KOH / g.

[0092] The hydroxyl value and acid value in this specification are basically theoretical values ​​derived from the components that make up the sealing layer. When the theoretical value cannot be derived, the value is measured according to JIS K0070.

[0093] (1)Adhesive layer As the sealing layer 4 in this embodiment, from the perspective of easily achieving the above-mentioned amount of acidic groups and easily achieving the desired sealing performance, it is preferred to be an adhesive layer composed of an adhesive.

[0094] While not particularly limited, transparent adhesives are preferred for easy and clear viewing of aerial images. Furthermore, while acrylic, rubber, silicone, and polyester adhesives can be cited as specific examples, acrylic adhesives are preferred for achieving the desired adhesion and transparency. Additionally, the adhesive can be solvent-based, solvent-free, or emulsion-based. Moreover, from the perspective of SDGs (Safety, Health, and Food Safety), materials constituting the adhesive can be high-biomass materials, recyclable or reusable materials, or materials that have been recycled or reused.

[0095] The aforementioned acrylic adhesives are preferably composed of adhesive compositions using (meth)acrylate polymers as the main agent, and particularly preferably of adhesive compositions containing (meth)acrylate polymers and crosslinking agents. Furthermore, in this specification, (meth)acrylate refers to both acrylates and methacrylates. Other similar terms are also used. Additionally, "polymer" also includes the concept of "copolymer."

[0096] (1-1) (Meth)acrylate polymer For (meth)acrylate polymers, from the perspective of easily exhibiting the desired adhesive force (especially the adhesiveness to adhered objects such as light diffusion control parts and light-transmitting imaging parts), it is preferable to contain (meth)acrylate alkyl esters as the monomer unit constituting the polymer, and more preferably (meth)acrylate alkyl esters containing alkyl groups with 1 to 20 carbon atoms.

[0097] Examples of alkyl methacrylates with 1 to 20 carbon atoms in the alkyl group include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, n-decyl methacrylate, n-dodecyl methacrylate, myristyl methacrylate, palmitate methacrylate, stearate methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, and adamantane methacrylate. From the perspective of improving adhesion and suppressing air bubbles, alkyl methacrylates with 1 to 8 carbon atoms in the alkyl group are preferred, and at least one of methyl methacrylate, 2-ethylhexyl methacrylate, and isobornyl methacrylate is preferred. These can be used alone or in combination of two or more.

[0098] For (meth)acrylate polymers, from the perspective of improving adhesion, suppressing foaming at the interface with the adherend, and the possibility of introducing other monomer components such as monomers containing reactive functional groups into the (meth)acrylate polymer in appropriate amounts, the monomer units constituting the polymer are preferably (meth)acrylate alkyl esters containing 50 to 99.9% by mass of an alkyl group having 1 to 20 carbon atoms, more preferably 60 to 99% by mass, particularly preferably 70 to 95% by mass, and even more preferably 75 to 90% by mass.

[0099] For (meth)acrylate polymers, monomer units constituting the polymer are preferably monomers containing reactive functional groups within the molecule. In particular, when the adhesive composition contains a crosslinking agent, the reactive functional groups of the monomers containing reactive functional groups react with the crosslinking agent, thereby making it easier to control the cohesive force of the resulting adhesive. Consequently, the resulting adhesive layer readily exhibits the desired adhesive strength.

[0100] As monomers containing reactive functional groups, preferred examples include monomers with an intramolecular hydroxyl group (hydroxyl-containing monomers), monomers with an intramolecular carboxyl group (carboxyl-containing monomers), and monomers with an intramolecular amino group (amino-containing monomers). Among these, monomers containing hydroxyl or carboxyl groups are preferred, and monomers containing hydroxyl groups are particularly preferred. These monomers containing reactive functional groups can be used alone or in combination of two or more.

[0101] Examples of hydroxyl-containing monomers include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, and other hydroxyalkyl methacrylates. Among these, 2-hydroxyethyl methacrylate or 4-hydroxybutyl methacrylate is preferred, with 2-hydroxyethyl methacrylate being the most preferred. These hydroxyl-containing monomers can be used alone or in combination of two or more.

[0102] Examples of carboxyl-containing monomers include ethyl unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These carboxyl-containing monomers can be used alone or in combination of two or more.

[0103] Examples of amino-containing monomers include aminoethyl (meth)acrylate and n-butylaminoethyl (meth)acrylate. These amino-containing monomers can be used alone or in combination of two or more.

[0104] For (meth)acrylate polymers, the monomer units constituting the polymer preferably contain 0.1 to 50% by mass of monomers containing reactive functional groups, more preferably 1 to 50% by mass, particularly preferably 4 to 40% by mass, and even more preferably 8 to 30% by mass, and most preferably 12 to 25% by mass. This readily improves the adhesiveness of the resulting adhesive, makes the adhesive layer exhibit the desired adhesion, and easily suppresses foaming at the interface with the adherend.

[0105] For the aforementioned (meth)acrylate polymer, a nitrogen-containing monomer is preferred as a constituent unit of the polymer. By having a nitrogen-containing monomer as a structural unit in the polymer, a predetermined polarity can be imparted to the adhesive, resulting in excellent affinity even for adherends with a certain degree of polarity, such as glass. From the perspective of giving the (meth)acrylate polymer appropriate rigidity, a monomer having a nitrogen-containing heterocycle is preferred as the aforementioned nitrogen-containing monomer. Furthermore, from the perspective of increasing the degree of freedom of the portion derived from the aforementioned nitrogen-containing monomer in the high-dimensional structure of the constructed adhesive, this nitrogen-containing monomer preferably does not contain reactive unsaturated double bond groups other than one polymerizable group used for the polymerization of the (meth)acrylate polymer.

[0106] Examples of monomers containing nitrogen-containing heterocycles include N-(meth)acryloylmorpholine, N-vinyl-2-pyrrolidone, N-(meth)acryloylpyrrolidone, N-(meth)acryloylpiperidine, N-(meth)acryloylpyrrolidine, N-(meth)acryloylaziridine, aziridine ethyl (meth)acrylate, 2-vinylpyridine, 4-vinylpyridine, 2-vinylpyrazine, 1-vinylimidazolium, N-vinylcarbazole, and N-vinylphthalimide. Among these, N-(meth)acryloylmorpholine, which exhibits superior adhesive properties, is preferred. These monomers can be used alone or in combination of two or more.

[0107] For (meth)acrylate polymers, when a nitrogen-containing monomer is included as a monomer unit constituting the polymer, it is preferable to contain 0.1 to 30% by mass of the nitrogen-containing monomer, more preferably 0.5 to 20% by mass, particularly preferably 1 to 15% by mass, and even more preferably 3 to 10% by mass. As a result, the adhesive exhibits excellent adhesion even to polar substrates, while easily suppressing foaming at the interface with the substrate.

[0108] (Meth)acrylate polymers can be copolymerized from the aforementioned alkyl (meth)acrylates, monomers containing reactive functional groups, and other monomers. As other monomers, monomers without reactive functional groups are preferred to avoid hindering the aforementioned effects of the monomers containing reactive functional groups. Examples of such monomers include methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, alkoxyalkyl (meth)acrylates, vinyl acetate, and styrene. These monomers can be used alone or in combination of two or more. Furthermore, the polymerization method of this polymer can be a random copolymer or a block copolymer. Additionally, this polymer can be used alone or in combination of two or more.

[0109] The weight-average molecular weight of the (meth)acrylate polymer is preferably 50,000 to 3,000,000, more preferably 100,000 to 2,400,000, particularly preferably 200,000 to 1,800,000, further preferably 300,000 to 1,200,000, and most preferably 400,000 to 750,000. This results in good cohesion of the adhesive, and consequently, the resulting adhesive layer easily exerts the desired adhesive force while effectively suppressing foaming at the interface with the adherend.

[0110] (1-2) Crosslinking agent The crosslinking agent can be any reactive functional group possessed by the (meth)acrylate polymer. Examples include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, amine-based crosslinking agents, melamine-based crosslinking agents, aziridine-based crosslinking agents, hydrazine-based crosslinking agents, aldehyde-based crosslinking agents, oxazoline-based crosslinking agents, metal alkoxide-based crosslinking agents, metal chelate-based crosslinking agents, metal salt-based crosslinking agents, and ammonium salt-based crosslinking agents. Among these, isocyanate-based crosslinking agents with excellent reactivity with hydroxyl and carboxyl groups, or epoxy-based crosslinking agents with excellent reactivity with carboxyl groups, are preferred. Furthermore, a single crosslinking agent or a combination of two or more crosslinking agents can be used.

[0111] Isocyanate-based crosslinking agents include at least polyisocyanate compounds. Examples of polyisocyanate compounds include aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, and phenylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate; biuret forms and isocyanurate forms of these polyisocyanate compounds; and further, adducts of reactants containing low molecular weight active hydrogen compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. From the perspective of reactivity with hydroxyl groups, trimethylolpropane-modified aromatic polyisocyanates are preferred, and trimethylolpropane-modified toluene diisocyanate and trimethylolpropane-modified phenylene diisocyanate are particularly preferred.

[0112] Examples of epoxy-based crosslinking agents include, for instance, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-phenylenediamine, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, and diglycidylamine.

[0113] The crosslinking agent content in the adhesive composition is preferably 0.02 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, particularly preferably 0.08 to 5 parts by weight, and even more preferably 0.1 to 1 part by weight, relative to 100 parts by weight of the (meth)acrylate polymer. This results in adhesives with suitable physical properties and adhesion strength, while also easily suppressing foaming at the interface with the adhered objects.

[0114] (1-3) Various additives The adhesive composition described above may contain various additives commonly used in acrylic adhesives, such as ultraviolet absorbers, silane coupling agents, photopolymerization initiators, antistatic agents, infrared absorbers, rust inhibitors, colorants, oxygen absorbers, surfactants, tackifiers, antioxidants, light stabilizers, softeners, fillers, and refractive index modifiers.

[0115] Among the aforementioned additives, ultraviolet (UV) absorbers are preferred. Using UV absorbers results in a more durable adhesive layer. Examples of preferred UV absorbers include compounds such as benzotriazole, benzophenone, benzoate, benzoxazinone, triazine, phenyl salicylate, cyanoacrylate, and nickel complex salts. These UV absorbers can be used individually or in combination of two or more.

[0116] The content of ultraviolet absorber in the adhesive composition is preferably 0.1 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, particularly preferably 1 to 10 parts by weight, and even more preferably 2 to 5 parts by weight, relative to 100 parts by weight of (meth)acrylate polymer. This results in a more durable adhesive layer.

[0117] Of the additives, silane coupling agents are preferably used. By using silane coupling agents, the adhesion to the substrate, whether it is a plastic sheet or a glass component, can be improved, and the aforementioned durability becomes even better.

[0118] As a silane coupling agent, an organosilicon compound having at least one alkoxysilane group in the molecule is preferred, and the organosilicon compound has good compatibility with (meth)acrylate polymers and is transparent.

[0119] Examples of silane coupling agents include, for example, silicon compounds containing polymerizable unsaturated groups such as vinyltrimethoxysilane, vinyltriethoxysilane, and methacryloyloxypropyltrimethoxysilane; silicon compounds with epoxy structures such as 3-epoxypropoxypropyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; and silicon compounds containing mercapto groups such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropyldimethoxymethylsilane. The compounds include amino-containing silicon compounds such as 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane; 3-chloropropyltrimethoxysilane; 3-isocyanatopropyltriethoxysilane; or condensates of at least one of these compounds with alkyl-containing silicon compounds such as methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, and ethyltrimethoxysilane. These compounds may be used alone or in combination of two or more.

[0120] The content of silane coupling agent in the adhesive composition is preferably 0.01 to 2 parts by weight, more preferably 0.04 to 1 part by weight or more, particularly preferably 0.08 to 0.6 parts by weight, and even more preferably 0.1 to 0.3 parts by weight, relative to 100 parts by weight of (meth)acrylate polymer. Therefore, the adhesion to the adhered object, whether it is a plastic sheet or a glass component, can be improved, and the durability becomes superior.

[0121] (1-4) Preparation of adhesive compositions The above-mentioned adhesive composition can be prepared by mixing (meth)acrylate polymers, crosslinking agents, and other additives.

[0122] (Meth)acrylate polymers can be manufactured by polymerizing a mixture of monomer units constituting the polymer using conventional free radical polymerization. The polymerization of (meth)acrylate polymers can be carried out using a polymerization initiator, as desired, and via solution polymerization or similar methods. Examples of polymerization solvents include ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, and methyl ethyl ketone; two or more can be used simultaneously. Examples of polymerization initiators include azo compounds and organic peroxides; two or more can be used simultaneously. Furthermore, in the above polymerization process, the weight-average molecular weight of the obtained polymer can be adjusted by incorporating chain transfer agents such as 2-mercaptoethanol.

[0123] After obtaining the (meth)acrylate polymer, a crosslinking agent and other desired additives are added to a solution of the (meth)acrylate polymer and thoroughly mixed to obtain an adhesive composition (coating solution) diluted with a solvent.

[0124] As a diluent for preparing a coating solution by diluting the adhesive composition, solvents such as aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as dichloromethane and dichloroethane, alcohols such as methanol, ethanol, propanol, butanol, and 1-methoxy-2-propanol, acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone, esters such as ethyl acetate and butyl acetate, and solvents such as ethyl solvents can be used.

[0125] The concentration and viscosity of the coating solution prepared in this way are not particularly limited as long as they are within a coatable range, and can be selected appropriately according to the situation. For example, the adhesive composition can be diluted to a concentration of 10 to 40% by mass. In addition, the addition of diluents is not necessary when obtaining the coating solution; as long as the adhesive composition has a coatable viscosity, diluents may not be added.

[0126] (1-5) Formation of adhesive layer The adhesive layer is preferably composed of an adhesive formed by crosslinking the above-described adhesive composition. Crosslinking of the adhesive composition can typically be achieved through heat treatment. Furthermore, this heat treatment can also serve as a drying process to allow diluents or the like to evaporate from the coating layer of the adhesive composition applied to the desired object.

[0127] The heating temperature for the heat treatment is preferably 50~150℃, and more preferably 70~120℃. Furthermore, the heating time is preferably 10 seconds~10 minutes, and more preferably 50 seconds~2 minutes.

[0128] After heat treatment, a curing period of approximately 1 to 2 weeks at room temperature (e.g., 23°C, 50%RH) can be set as needed. If this curing period is required, an adhesive will form after the curing period; if no curing period is required, the adhesive will form immediately after the heat treatment. Additionally, in this specification, "relative humidity α%" is sometimes expressed as "α%RH" (RH; Relative humidity).

[0129] Through the above-mentioned heat treatment (and aging), the (meth)acrylate polymer is fully cross-linked via a cross-linking agent.

[0130] (2) Adhesive layer and adhesive layer As described above, the sealing layer 4 of this embodiment can be an adhesive layer made of an adhesive, or it can be an adhesive layer made of an adhesive bonding agent. There are no particular limitations on these adhesives and adhesive bonding agents, as long as the amount of acidic groups described above is met, and common substances can be used.

[0131] (3) Total light transmittance of the sealing layer The total light transmittance of the sealing layer 4 in this embodiment is preferably 80% or more, particularly preferably 85% or more, and even more preferably 90% or more. Furthermore, there is no particular limitation on the upper limit of this total light transmittance, but it is preferably 100%. This facilitates clear and accurate viewing of aerial images. The detailed method for measuring the total light transmittance is described in the experimental examples below.

[0132] (4) Thickness of the sealing layer The thickness of the sealing layer 4 in this embodiment is preferably 1~100μm, more preferably 3~80μm, particularly preferably 5~60μm, and even more preferably 7~40μm, with 9~20μm being the most suitable. This allows for easy and effective sealing between the light diffusion control unit 2 and the light-transmitting imaging unit 3, and also effectively suppresses the generation of air bubbles.

[0133] 6. Other constituent elements The aerial imaging devices 10a and 10b of this embodiment may also include components other than the display unit 1, light diffusion control unit 2, light-transmitting imaging unit 3, and sealing layer 4 described above. In particular, the aerial imaging device 10 of this embodiment preferably includes a frame for fixing and housing the display unit 1, light diffusion control unit 2, light-transmitting imaging unit 3, and sealing layer 4 in a predetermined position.

[0134] The material, shape, and size of the frame can be appropriately selected according to the application and purpose. In particular, it is preferable that the frame is made of a light-shielding material to prevent light from the display unit 1 from leaking to the outside unintentionally, while also preventing unintentional external light from entering the light path from the display unit 1 to the light diffusion control unit 2 or the light-transmitting imaging unit 3.

[0135] 7. Positional relationships of the elements In the aerial imaging devices 10a and 10b of this embodiment, it is assumed that Figure 3 While considering the first direction indicated by "D1", the second direction is assumed to be: a direction parallel to a plane perpendicular to both the display surface of the display unit 1 and a surface of the light diffusion control unit 2, existing within the plane of the light diffusion control unit 2 on the side opposite to the light-transmitting imaging unit 3; in this case, the acute angle formed by the first direction and the second direction is preferably 0° or more and 90° or less. Regardless of the acute angle, by considering the incident angle of light onto the light diffusion control unit 2 within the plane including D1 and perpendicular to the light diffusion control unit 2, the aerial imaging devices 10a and 10b of this embodiment can easily suppress the generation of ghosting or interfering light, and can easily display aerial images more brightly.

[0136] Furthermore, when the aerial imaging devices 10a and 10b of this embodiment are equipped with a retrotransmitting optical element having the above-mentioned dihedral reflector array structure as a light-transmitting imaging unit 3, or a retrotransmitting optical element formed by two layers stacked with multiple reflective surfaces, the following conditions are preferably met.

[0137] First, as a premise, assume a plane F that is perpendicular to both the surface of the light-transmitting imaging section 3 opposite to the light diffusion control section 2 and the display surface of the display section 1, and passes through the center point of the light-transmitting imaging section 3. Furthermore, the width of the light-transmitting imaging section 3 in the cross-section formed by cutting through the light-transmitting imaging section 3 using this plane F is defined as width W.

[0138] Furthermore, assume the following observation point: the observation point exists in the plane F mentioned above, and the observation point satisfies both of the following conditions A and B. (Condition A) When the angle formed by the line segment connecting the observation point and the center point with the surface of the light-transmitting imaging unit 3 on the opposite side of the light diffusion control unit 2 is set as angle α, and the angle formed by the plane containing the display surface of the display unit 1 with the plane containing the surface of the light-transmitting imaging unit 3 on the opposite side of the light diffusion control unit 2 is set as angle β, the total angle α and angle β is 90°. (Condition B) The distance between the observation point and the center point is 1 to 10 times the width W.

[0139] Furthermore, it should be noted that condition A above refers to determining the position of the observation point based on the positional relationship between the display unit 1 and the light-transmitting imaging unit 3 in the aerial imaging device 10. For example, for an aerial imaging device 10 in which the display unit 1 and the light-transmitting imaging unit 3 are arranged such that the angle β is 45°, the angle α of the observation point is 45°; for an aerial imaging device 10 in which the angle β is 60°, the angle α of the observation point is 30°.

[0140] Furthermore, regarding condition B above, the expression "1 to 10 times the width W" means that the observation point only needs to satisfy the condition of any point within this range. A particularly preferred condition B is "the distance between the observation point and the center point is 3.5 times the width W."

[0141] Furthermore, the configuration of each element of the aerial imaging device 10 is preferably such that when the aerial imaging device 10a and 10b are observed from the observation point, the light diffusion control unit 2 simultaneously satisfies the following two conditions. (Condition 1) Of the light that reaches the observation point from any point on the display unit 1, the haze value is 60% or less for the light reflected in each of the two layers constituting the retrotransmission optical element. (Condition 2) Of the light that reaches the observation point from any point on the display unit 1, the haze value is 60% or higher for light that is reflected in only one of the two layers constituting the retrotransmission optical element.

[0142] By ensuring that the aerial imaging devices 10a and 10b of this embodiment meet the above conditions, it is easy to suppress the occurrence of ghosting or interfering light, and at the same time, it is easy to display aerial images more brightly.

[0143] Here, "reflection occurs in each of the two layers" or "reflection occurs in only one of the two layers" does not refer to physical reflection, but rather to reflection in the sense of a change in direction. Because the mirrors in the retrotransmission optical element, which consists of two stacked layers with multiple reflective surfaces, are arranged in parallel, the direction changes with an odd number of reflections, while the direction remains unchanged with an even number of reflections. Therefore, "reflection occurs" in the above statement can be rephrased as "odd-numbered reflections result in a change in direction."

[0144] 8. Manufacturing method of aerial imaging device The manufacturing method of the aerial imaging devices 10a and 10b in this embodiment is not particularly limited. For example, after preparing the display unit 1, the light diffusion control unit 2, the light-transmitting imaging unit 3, and the sealing layer 4 respectively, the aerial imaging devices 10a and 10b can be obtained by setting the display unit 1 at a predetermined position on the frame and simultaneously setting a laminate of the light diffusion control unit 2, the light-transmitting imaging unit 3, and the sealing layer 4.

[0145] 9. How to use aerial imaging devices The aerial imaging devices 10a and 10b of this embodiment can be used as display devices to display any image or video in the air. There are no specific limitations on their usage; they can be used in the same manner as conventionally known display devices.

[0146] [Layered structure] The display unit 1 is omitted from the aerial imaging devices 10a and 10b described above in this embodiment. That is, the stacked body of this embodiment includes: a light-transmitting imaging unit 3 that images light incident from one surface at a position on another surface; a light diffusion control unit 2 stacked on one surface of the light-transmitting imaging unit 3; and a sealing layer 4 stacked between the light-transmitting imaging unit 3 and the light diffusion control unit 2, sealing the light-transmitting imaging unit 3 and the light diffusion control unit 2 together. Here, the composition or structure of the light-transmitting imaging unit 3, the light diffusion control unit 2, and the sealing layer 4 are as described above.

[0147] The laminated body of this embodiment can be obtained by stacking the light diffusion control unit 2, the light-transmitting imaging unit 3, and the sealing layer 4 after preparing them separately. Furthermore, the laminated body of this embodiment can be used to form the aerial imaging devices 10a and 10b of this embodiment. That is, the aerial imaging devices 10a and 10b of this embodiment can be obtained by arranging the display unit 1 at a predetermined position relative to the laminated body of this embodiment.

[0148] Furthermore, in this specification, when "X~Y" (where X and Y are arbitrary numbers) is used, unless otherwise specified, it includes the meaning of "X or more and Y or less," and also includes the meaning of "preferably greater than X" or "preferably less than Y." Additionally, when "X or more" (where X is any number) is used, unless otherwise specified, it includes the meaning of "preferably greater than X," and when "Y or less" (where Y is any number) is used, unless otherwise specified, it includes the meaning of "preferably less than Y."

[0149] The embodiments described above are provided for ease of understanding of the present invention and are not intended to limit the present invention. Therefore, the elements disclosed in the above embodiments also cover all design changes and equivalent technical solutions that fall within the technical scope of the present invention. Example

[0150] The present invention will be further described in detail below through examples, etc., but the scope of the present invention is not limited by these examples, etc.

[0151] [Example 1] 1. Preparation of a composition for light diffusion control Polypropylene glycol, isophorone diisocyanate, and 2-hydroxyethyl methacrylate, which are low-refractive-index components, are reacted. To obtain a polyether urethane methacrylate with a weight-average molecular weight of 9,900, 40 parts by mass (solid component conversion value; the same applies below) are added, along with 60 parts by mass of o-phenylphenoxyethoxyethyl acrylate with a molecular weight of 268, which is a high-refractive-index component, and 8 parts by mass of 2-hydroxy-2-methyl-1-phenylpropane-1-one, which is a photopolymerization initiator. The mixture is then heated and mixed at 80°C to obtain a composition for light diffusion control.

[0152] The weight-average molecular weight (Mw) is the weight-average molecular weight converted from standard polystyrene determined by gel permeation chromatography (GPC) under the following conditions (GPC determination). <Measurement Conditions> • Measuring device: Tosoh Corporation, HLC-8320 • GPC pillars (passing in the following order): Manufactured by Tosoh Corporation TSK gel superH-H TSK gel superHM-H TSK gel superH2000 • Solvent for determination: Tetrahydrofuran • Measurement temperature: 40℃

[0153] 2. Formation of the light diffusion control section The obtained light diffusion control component is coated onto a polyethylene terephthalate film (thickness: 50 μm) serving as engineering sheet A using the composition, forming a coating film. This yields a laminate consisting of the coating film and engineering sheet A.

[0154] Next, the obtained laminate is placed on a conveyor belt. At this time, the coating side of the laminate is facing upwards, and the long side of the engineering sheet A is parallel to the conveyor belt's transport direction. Furthermore, an ultraviolet irradiation device (manufactured by EYE GRAPHICS COMPANY, product name "ECS-4011GX") is installed relative to the conveyor belt carrying the laminate. This ultraviolet irradiation device has a linear high-pressure mercury lamp with a focusing mirror. This device can irradiate a single point as a band (approximately linear) of ultraviolet light. Additionally, the ultraviolet irradiation device is installed such that the long side of the high-pressure mercury lamp is orthogonal to the conveyor belt's transport direction.

[0155] Furthermore, when viewed from the long side of the high-pressure mercury lamp, the normal to the surface of the laminate is used as a reference, and the irradiation angle of the ultraviolet light irradiating the laminate from the high-pressure mercury lamp is set to -5°. Additionally, this irradiation angle refers to the angle formed by the normal to the laminate surface and the ultraviolet light when irradiating the downstream side of the conveyor belt with the ultraviolet light directly below the high-pressure mercury lamp as a reference; when irradiating the upstream side of the conveyor belt, the acute angle formed by the normal to the laminate surface and the ultraviolet light is recorded as a negative sign.

[0156] Then, the conveyor belt is started, moving the above-mentioned laminate at a speed of 1.0 m / min while maintaining a peak illuminance of 2.5 mW / cm² on the coating surface. 2 The cumulative light intensity is 40.0 mJ / cm². 2 Under certain conditions, ultraviolet light is irradiated, thereby curing the coating in the laminate (for convenience, this curing is sometimes referred to as "one-time curing").

[0157] Next, a polyethylene terephthalate film (thickness: 38 μm) as engineering sheet B is laminated on the coating side of the laminate to obtain a laminate consisting of engineering sheet A, the above coating film, and engineering sheet B in sequence.

[0158] Then, while moving it at a speed of 1.0 m / min, the peak illuminance of the engineering plate B is 190 mW / cm². 2 The cumulative light intensity is 180 mJ / cm². 2Under certain conditions, the coating is irradiated with ultraviolet light (scattered light) to cure the coating in the laminate (for convenience, this curing is sometimes referred to as "secondary curing"). Furthermore, the peak illuminance and cumulative light intensity mentioned above were measured by placing a UV METER (manufactured by EYE GRAPHICS COMPANY, product name "Eye UV PF-A1") equipped with a light receiver at the location of the coating.

[0159] Through the above-mentioned primary and secondary curing processes, the coating film is fully cured, forming a light diffusion control section. Thus, a laminate consisting of engineering sheet A, a light diffusion control section with a thickness of 200 μm, and engineering sheet B are obtained by sequentially stacking them.

[0160] Furthermore, after microscopic observation of the cross-section of the formed light diffusion control section, it was confirmed that, for example... Figure 3 As shown, multiple plate-shaped regions 201 are formed inside the light diffusion control unit, forming a louver structure arranged in parallel at predetermined intervals. The acute angle between the main surface of the louver structure and the normal to the light diffusion control unit is 3.3°.

[0161] 3. Formation of the adhesive layer A (meth)acrylate polymer was obtained by copolymerization of 65 parts by mass of 2-ethylhexyl acrylate, 15 parts by mass of isobornyl acrylate, 5 parts by mass of N-acryloylmorpholine, and 15 parts by mass of 2-hydroxyethyl acrylate using solution polymerization. The weight-average molecular weight (Mw) of the (meth)acrylate polymer was determined by the above method and found to be 500,000.

[0162] 100 parts by weight of the obtained (meth)acrylate polymer, 0.6 parts by weight of an epoxy curing agent (manufactured by Soken Chemical Co., Ltd., product name "E-AX") as a crosslinking agent, and 4 parts by weight of a triazine UV absorber (manufactured by BASF JAPAN, product name "Tinuvin 477") as a UV absorber were mixed and stirred thoroughly, and then diluted with ethyl acetate to obtain a coating solution of the adhesive composition.

[0163] The obtained coating solution was applied to the release treatment surface of a heavy-release type release sheet C (thickness: 38 μm) that had been treated by removing one side of a polyethylene terephthalate film using an organosilicon-based release agent using a doctor blade coater. The film was then dried in a drying oven at 90°C for 1 minute to obtain a coating layer with a thickness of 13 μm.

[0164] Next, a lightly peelable release sheet D (thickness: 38 μm) that has undergone a peeling treatment on one side of the polyethylene terephthalate film using a silicone-based release agent is attached to the side of the above-mentioned coating layer opposite to the release sheet C. Then, by curing at 23°C and 50%RH for 7 days, the above-mentioned coating layer is set as an adhesive layer serving as a sealing layer.

[0165] From the above, a laminate consisting of a release sheet C, an adhesive layer with a thickness of 13 μm, and a release sheet D is obtained by sequentially stacking them.

[0166] Specifically, the amount of acidic groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated to be 0 mmol / g. Furthermore, the amount of hydroxyl groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated to be 1.29 mmol / g.

[0167] Furthermore, the hydroxyl value of the components constituting the adhesive layer was calculated, and the result was 72.48 mg KOH / g. The acid value of the components constituting the adhesive layer was calculated, and the result was 0 mg KOH / g.

[0168] 4. Fabrication of laminated bodies Peel off the engineering sheet B from the laminate obtained in step (2) above to expose the light diffusion control section. Next, peel off the release sheet D from the laminate obtained in step (3) above, and attach the exposed surface of the adhesive layer therefrom to the exposed surface of the light diffusion control section.

[0169] Furthermore, the release piece C is peeled off, and the exposed surface of the adhesive layer is stacked on one side of a retro-transmitting optical element (manufactured by Asukanet Co., Ltd., product name "ASKA3D-200NT", 200mm in length × 200mm in width × 6.3mm in thickness) which is a light-transmitting imaging part and is made of two layers having multiple reflective surfaces.

[0170] Thus, a laminate is obtained by sequentially stacking an engineering sheet, a light diffusion control section, a sealing layer (adhesive layer), and a light-transmitting imaging section (reverse transmission optical element).

[0171] [Example 2] The (meth)acrylate polymer was obtained by copolymerizing 60 parts by mass of 2-ethylhexyl acrylate, 20 parts by mass of methyl methacrylate, and 20 parts by mass of 2-hydroxyethyl acrylate using solution polymerization. The weight-average molecular weight (Mw) of the (meth)acrylate polymer was determined by the above method and found to be 700,000.

[0172] 100 parts by weight of the obtained (meth)acrylate polymer, 0.25 parts by weight of an isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, Inc., product name "TAKENATE D-101E"), and 0.1 parts by weight of 3-epoxypropoxypropylmethyldiethoxysilane as a silane coupling agent were mixed and stirred thoroughly, and then diluted with ethyl acetate to obtain a coating solution of the adhesive composition.

[0173] Except for using the coating solution of the obtained adhesive composition, a laminate consisting of an engineering sheet, a light diffusion control section, an adhesive layer (adhesive layer), and a light-transmitting imaging section (reverse transmission optical element) was obtained in the same manner as in Example 1.

[0174] Specifically, the amount of acidic groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated, and the result was 0 mmol / g. Furthermore, the amount of hydroxyl groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated, and the result was 1.72 mmol / g.

[0175] In addition, the hydroxyl value of the components constituting the above-mentioned sealing layer was calculated to be 96.64 mg KOH / g, and the acid value of the components constituting the above-mentioned sealing layer was calculated to be 0 mg KOH / g.

[0176] [Comparative Example 1] A (meth)acrylate polymer was obtained by copolymerization of 67.2 parts by mass of 2-ethylhexyl acrylate, 5 parts by mass of methyl methacrylate, 8 parts by mass of methacrylic acid, 18 parts by mass of vinyl acetate, 0.4 parts by mass of acrylic acid, and 1.4 parts by mass of 4-hydroxybutyl acrylate using solution polymerization. The weight-average molecular weight (Mw) of the (meth)acrylate polymer was determined by the above method and found to be 820,000.

[0177] 100 parts by weight of the obtained (meth)acrylate polymer, 0.5 parts by weight of an isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, product name "Coronate HX"), and 7.7 parts by weight of a triazine-based ultraviolet absorber (manufactured by BASF JAPAN, product name "Tinuvin 477") were mixed and stirred thoroughly, and then diluted with ethyl acetate to obtain a coating solution of the adhesive composition.

[0178] Except for using the coating solution of the obtained adhesive composition, a laminate consisting of an engineering sheet, a light diffusion control section, an adhesive layer (adhesive layer), and a light-transmitting imaging section (reverse transmission optical element) was obtained in the same manner as in Example 1.

[0179] Specifically, the amount of acidic groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated to be 0.055 mmol / g. Furthermore, the amount of hydroxyl groups present in the adhesive layer relative to all components constituting the adhesive layer was calculated to be 0.15 mmol / g.

[0180] In addition, the hydroxyl value of the components constituting the above-mentioned sealing layer was calculated to be 8.56 mg KOH / g, and the acid value of the components constituting the above-mentioned sealing layer was calculated to be 3.11 mg KOH / g.

[0181] [Experimental Example 1] (Determination of the total light transmittance of the sealing layer) The total transmittance (%) of the adhesive layers (adhesive layers) prepared in the examples and comparative examples was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd., product name "NDH7000"), based on JIS K7361-1:1997 and ASTM D 1003. The results are shown in Table 1.

[0182] [Table 1]

[0183] [Experimental Example 2] (Durability Test) The laminates (laminates of an engineering sheet, a light diffusion control unit, an adhesive layer, and a light-transmitting imaging unit (reverse transmission optical element) sequentially stacked in the examples and comparative examples) were stored at 80°C for 500 hours (80°C dry test). Then, they were removed at 23°C and 50%RH, and while photographing each laminate, the appearance of air bubbles generated between the light diffusion control unit and the adhesive layer, and between the adhesive layer and the light-transmitting imaging unit (reverse transmission optical element) was visually confirmed. The images obtained are shown below. Figure 5 In addition, for each case, two stacks were tested.

[0184] As a result, in Example 1 ( Figure 5 In the laminate of Example 1 (a), a small number of air bubbles were identified, while in the laminate of Example 2 (coating 5, b), no air bubbles were identified. In contrast, in Comparative Example 1 (… Figure 5 A large number of air bubbles were identified in the stack of (c)).

[0185] In addition, separately prepared laminates were stored under humid heat conditions of 60°C and 90%RH for 500 hours (60°C, 90%RH test). Then, they were removed at 23°C and 50%RH, and while photographing each laminate, air bubbles were checked using the same method as described above. The images obtained are shown below. Figure 6In addition, for each case, two laminates were tested.

[0186] As a result, in Example 1 ( Figure 6 (a) and Example 2 ( Figure 6 In the laminate of (b)), no air bubbles were identified. In contrast, in Comparative Example 1 ( Figure 6 In the laminate of (c)), a large amount of foaming was confirmed. Additionally, according to Figure 6 (b) It can be confirmed that a small number of small bubbles are generated, but these are caused by foreign matter mixed in during the formation of the laminate, not by the 60°C, 90%RH test.

[0187] Furthermore, for the laminates of Examples 1 and 2 that underwent the aforementioned 80°C dry test, the position of each end was visually confirmed and photographed. The acquired images are shown below. Figure 7 .

[0188] As a result, in Example 1 ( Figure 7 In (a)), it was confirmed that a small amount of lifting and peeling occurred at the end, whereas in Example 2 ( Figure 7 In the stacked body of (b)), no buoyancy or peeling was identified. [Industrial Applicability]

[0189] The aerial imaging device of the present invention is suitable for use as a display for showing aerial images, etc. Explanation of reference numerals in the attached figures

[0190] 10a, 10b: Aerial imaging device; 1: Display unit; 2: Light diffusion control unit; 201: Plate-shaped area; 202: Area with relatively low refractive index; 3: Transmitting imaging unit; 4: Sealing layer; 5: Aerial image observation surface; 6: Observation point.

Claims

1. An aerial imaging device, characterized in that, It possesses: A display unit having a display surface from which light is emitted; A light-transmitting imaging unit is disposed on the display surface side of the display unit; A light diffusion control unit is stacked on the side of the light-transmitting imaging unit opposite to the display unit or on the side of the light-transmitting imaging unit that is the display unit; A sealing layer is layered between the light-transmitting imaging part and the light diffusion control part to ensure a tight seal between them. The light-transmitting imaging unit transmits light from the display surface and forms an image on a side opposite to the display surface. The light diffusion control unit causes light incident upon it to diffuse or transmit according to its incident angle, and has a regular internal structure resembling louvers with multiple plate-like regions having relatively high refractive index in regions with relatively low refractive index. The adhesive layer is composed of any one of an adhesive, a binder, and an adhesive bonding agent, and the amount of acidic groups present in the adhesive layer is less than 0.050 mmol / g relative to all the components constituting the adhesive layer.

2. The aerial imaging device according to claim 1, characterized in that, The amount of hydroxyl groups present in the adhesive layer is 0.2 mmol / g or more and 20.0 mol / g or less, relative to all the components constituting the adhesive layer.

3. The aerial imaging device according to claim 1, characterized in that, The hydroxyl value of the components constituting the sealing layer is 10 mg KOH / g or more and 500 mg KOH / g or less, and the acid value of the components constituting the sealing layer is 0 mg KOH / g or more and 3.0 mg KOH / g or less.

4. The aerial imaging device according to claim 1, characterized in that, The total light transmittance of the sealing layer is over 80%.

5. The aerial imaging device according to claim 1, characterized in that, The display unit is configured such that the display surface is not parallel to the surface of the light diffusion control unit opposite to the light-transmitting imaging unit.

6. The aerial imaging device according to claim 1, characterized in that, When the direction perpendicular to the long side of the plate-shaped region and existing in the plane of the light diffusion control section opposite to the light-transmitting imaging section is defined as the first direction, Each of the plate-shaped regions is inclined in the first direction within the light diffusion control unit.

7. The aerial imaging device according to claim 1, characterized in that, The light-transmitting imaging unit has a reverse transmission optical element that reverses the transmission of incident light.

8. The aerial imaging device according to claim 7, characterized in that, The retro-transmission optical element is composed of two stacked layers with multiple reflective surfaces. In each of the two layers, the plurality of reflective surfaces are arranged perpendicular to one surface of the retrotransmitting optical element and at predetermined intervals from each other. The two layers are stacked in such a way that the reflective surface of one layer is orthogonal to the reflective surface of the other layer.

9. A laminated body, characterized in that, It possesses: A light-transmitting imaging unit that images light incident from one surface at a position on the other side of the surface; A light diffusion control unit is stacked on one side of the light-transmitting imaging unit; A sealing layer is layered between the light-transmitting imaging part and the light diffusion control part to ensure a tight seal between them. The light diffusion control unit diffuses or transmits light incident upon it according to its incident angle, and has a regular, louver-like internal structure with multiple plate-like regions having relatively high refractive index in regions with relatively low refractive index. The adhesive layer is composed of any one of an adhesive, a binder, and an adhesive bonding agent, and the amount of acidic groups present in the adhesive layer is less than 0.050 mmol / g relative to all the components constituting the adhesive layer.

Images