JP4691910B2 - Screen reflector and screen - Google Patents

Description

  The present invention relates to a screen that displays an image by receiving light from a light source and a reflector for the screen.

  In recent years, an enlarged display on a screen using a liquid crystal projector, a slide projector or the like is generally performed. As this type of projector, for example, an illumination optical system that separates light beams emitted from a light source into light beams of each color of red (R), green (G), and blue (B) and converges them on a predetermined optical path, and RGB A liquid crystal panel (light valve) that light-modulates each color beam and a light combining unit that combines the light-modulated RGB color beams, and enlarges and projects the color image combined by the light combining unit onto the screen using a projection lens. There is something.

  Recently, a narrow band three primary color light source, for example, a laser oscillator that emits narrow band light of each RGB color, is used as a light source, and a RGB light beam is emitted using a grating light valve (GLV) instead of a liquid crystal panel. Spatial modulation projectors have also been developed.

  In such a projector, a projection screen is used. The projection screen is roughly classified into a transmission type and a reflection type. The transmissive screen transmits the projection light emitted from the projector behind the screen (rear projector) so that the projected image can be seen by the transmitted light. The reflective screen is a projector (front projector) The projection light irradiated from the front projector) is reflected so that the projected image can be seen by the reflected light. In either the transmission type or the reflection type, it has been conventionally necessary to darken the room in order to obtain an image with high brightness and high contrast.

  As such a projection screen, there are projection screens (for example, Patent Documents 1 and 2) that can obtain an image with high brightness and high contrast even in a bright place. The projection screen includes a reflector made of an optical multilayer film in which a high refractive index layer and a low refractive index layer are alternately laminated on a light-absorbing screen substrate, a light diffuser that scatters reflected light, and a protective film. Films are formed sequentially, reflecting only the three primary colors that make up the projection light, and transmitting the other light to be absorbed by the screen substrate, allowing high-contrast images to be displayed regardless of the projection environment. It is like that. However, in the conventional technology, the reflector constituting the screen is made of an inorganic material, so there is not much flexibility, and it is easy to get cracks and scratches during storage and repeated use, and the reflection characteristics deteriorate. There was a problem such as. Further, since the film is formed by the sputtering method, there is a problem that the cost is increased.

  On the other hand, several films in which thermoplastic resins are laminated in multiple layers have been proposed. For example, a film that selectively reflects a specific wavelength (for example, by selectively laminating resin layers having different refractive indexes in multiple layers) Patent Documents 3 to 5) and the like exist. Among these, a film that selectively reflects a specific wavelength acts as a filter that transmits or reflects specific light, and is used as a film for a backlight such as a liquid crystal display.

However, in the conventional technology, the uniformity of the reflection characteristics in a large area is insufficient when reflecting light of a specific narrow band such as RGB, so when a reflector is used, the color within the screen There was a problem of unevenness.
JP 2003-270725 A (page 2) JP 2004-138938 A (2nd page) Japanese Patent Laid-Open No. 3-41401 (2nd page) JP-A-4-295804 (page 2) Japanese translation of PCT publication No. 9-506837 (2nd page)

  The present invention provides a reflector and a screen that are suitable for a low-cost screen, in which reflection characteristics are hardly deteriorated in an actual use environment, and there is no color unevenness, in view of the above-described problems of the prior art. Is an issue.

In order to solve the above problems, a reflector for a screen of the present invention includes a side plate, a thermoplastic resin A supply unit, a slit unit, a thermoplastic resin B supply unit, a slit unit, a thermoplastic resin A supply unit, a slit unit, and a thermoplastic resin. The resin B supply part and the side plate are provided in this order, and each of the slit parts has a plurality of slits, and each slit part receives the thermoplastic resin A from the adjacent thermoplastic resin A supply part. The thermoplastic resin B is alternately supplied to the plurality of slits of the slit portion from the adjacent thermoplastic resin supply portion B, and the slit shape of each slit portion is a slit on the non-supply surface side. area) / (using a slit area) ≦ 50% der Ru off Idoburokku the supply side, resulting draft ratio (lip gap / casting film thickness) as 15 or less, Po Riechire Terephthalate is (thermoplastic resin A) consisting essentially of a layer and cyclohexane dimethanol copolymerized polyester (thermoplastic resin B) respectively stacked 25 layers or more layers alternately made of aligned laminated number to 50 or more, corresponding to RGB made from a polyester film for reflecting band, characterized in that one of the maximum reflectance of the band corresponding to the RGB is 60% or more, and thickness unevenness in the longitudinal direction and / or width direction is 5% or less And

The reflector for a screen of the present invention is a reflector that reflects one of the bands corresponding to RGB, and the reflector includes a side plate, a thermoplastic resin A supply unit, a slit unit, a thermoplastic resin B supply unit, and a slit. Part, thermoplastic resin A supply part, slit part, thermoplastic resin B supply part, and side plate are provided in this order, and each slit part has a plurality of slits, and each slit part is adjacent. The thermoplastic resin A is supplied from the thermoplastic resin A supply part, and the thermoplastic resin B is supplied alternately from the adjacent thermoplastic resin supply part B to the plurality of slits of the slit part. the shape of the slit of the slit portion with a (non-slit area of the supply side) / (the slit area of the supply side) ≦ 50% der Ru off Idoburokku, draft ratio (the lip gap / casting film Obtained only) as 15 or less, laminated port triethylene terephthalate (thermoplastic resin A) consisting essentially of a layer and cyclohexane dimethanol copolymerized polyester (thermoplastic resin B) becomes layers alternately to each 25 or more layers of a laminated It is composed of a polyester film that reflects a band corresponding to RGB, the number of which is 50 or more in total, the maximum reflectance of any of the bands corresponding to RGB is 60% or more, and the longitudinal direction and / or width Since the thickness unevenness in the direction is 5% or less, it is possible to provide a reflector suitable for a low-cost screen that is less likely to cause deterioration of reflection characteristics in an actual use environment and has no color unevenness. It will be like that.

  In addition, since the reflection band is asymmetric with respect to the maximum reflectance and the reflector for the screen tailing on the low wavelength side is also a preferred embodiment, the incident angle of the projection light from the projector or the like is from the vertical direction of the screen. This makes it possible to provide a reflector suitable for a low-cost screen that is unlikely to cause a decrease in contrast even if it is shifted, is less likely to cause deterioration of reflection characteristics in an actual usage environment, and has no color unevenness. is there.

In order to achieve the above object, the screen reflector of the present invention is a reflector that reflects one of the bands corresponding to RGB, and includes a side plate, a thermoplastic resin A supply section, a slit section, and a thermoplastic resin B supply section. A slit portion, a thermoplastic resin A supply portion, a slit portion, a thermoplastic resin B supply portion, and a side plate in this order, and each of the slit portions has a plurality of slits. Is configured such that the thermoplastic resin A is supplied alternately from the adjacent thermoplastic resin A supply section, and the thermoplastic resin B is supplied alternately from the adjacent thermoplastic resin supply section B to the plurality of slits of the slit section. the shape of the slits of each slit portion using (slit area of the non-feed side) / (the slit area of the supply side) ≦ 50% der Ru off Idoburokku, draft ratio (the lip gap /-casting Gufirumu obtained thickness) as 15 or less, laminated port triethylene terephthalate (thermoplastic resin A) consisting essentially of a layer and cyclohexane dimethanol copolymerized polyester (thermoplastic resin B) becomes layers alternately on each 25 layers or more from It is composed of a polyester film that reflects a band corresponding to RGB, the total number of layers of which is 50 or more, the maximum reflectance of any of the bands corresponding to RGB is 60% or more, and the longitudinal direction and / or The thickness unevenness in the width direction must be 5% or less. Since such a reflector for a screen is made of a thermoplastic resin, it has flexibility, is less susceptible to scratches and cracks due to deformation, and does not cause deterioration of reflection characteristics in an actual usage environment. In some cases, it is difficult to produce defects. Further, since the number of laminated layers is 50 or more, even if the surface is scratched, most of the layers are not affected, so that the reduction in the reflection characteristics is small. Furthermore, since the maximum reflectance in any of the bands corresponding to RGB is 60% or more and the distribution range of the maximum reflectance within 1 m 2 is 20% or less, high contrast is obtained when a screen is used. As well as color unevenness.

  Here, the band corresponding to RGB in the present invention specifically refers to a band in which R is 600 nm to less than 700 nm, G is 500 nm to less than 600 nm, and B is 400 nm to less than 500 nm, more preferably The three primary color bands in the vicinity of R (642 nm ± 25 nm), G (532 nm ± 25 nm), and B (457 nm ± 25 nm) constituting the projector light. The screen reflector of the present invention must have a maximum reflectivity of 60% or higher in any of these bands. More preferably, the maximum reflectance is 80% or more, and further preferably 90% or more. A higher maximum reflectance is preferable because higher contrast can be obtained. Here, the maximum reflectance is defined as the maximum reflectance in each band corresponding to RGB. Moreover, although it does not specifically limit about an upper limit, the reflectance of this invention is a comparative reflectance, and can be 100% or more.

The screen reflector of the present invention has a maximum reflectance of 60% or more in any of the bands corresponding to RGB . Moreover, the distribution range of the maximum reflectance within 1 m ² is 20% or less . This is defined as that the maximum reflectance of 60% or more of each reflectance is compared within each band of RGB at the positions of the four corners and the center in 1 m ² and the distribution range is 20% or less. Is. Here, the distribution range is a difference between the maximum value and the minimum value of the maximum reflectance at each measurement position. In such a case, the color unevenness due to the uneven reflectance is in a permissible range. More preferably, the maximum reflectance distribution range is 10% or less. In such a case, it is difficult to visually perceive color unevenness, which is hardly a problem. More preferably, it is 5% or less. In this case, even if the angle at which the screen is viewed is changed, the color unevenness can hardly be detected, which is preferable. Further, it is preferable that the wavelength distribution range giving the maximum reflectance within 1 m ² is 50 nm or less. More preferably, it is 25 nm or less. In such a case, high contrast can be obtained over a wide range.

As the thermoplastic resin in the present invention, more preferably Po Riesuteru resins. Further, these thermoplastic resins may be homo resins, copolymerized or blends of two or more. Also, in each thermoplastic resin, various additives such as antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, organic particles, thickeners, thermal stabilizers, lubricants, infrared absorbers, ultraviolet absorbers. An agent, a dopant for adjusting the refractive index, and the like may be added.

  The thermoplastic resin of the present invention is more preferably a polyester resin. The polyester referred to in the present invention refers to a homopolyester or a copolyester that is a polycondensate of a dicarboxylic acid component skeleton and a diol component skeleton. Here, typical examples of the homopolyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, and polyethylene diphenylate. In particular, polyethylene terephthalate is preferable because it is inexpensive and can be used in a wide variety of applications.

  The copolyester in the present invention is defined as a polycondensate comprising at least three or more components selected from the following dicarboxylic acid component skeleton and diol component skeleton. Examples of the dicarboxylic acid skeleton component include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 4 4,4'-diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, dimer acid, cyclohexanedicarboxylic acid and ester derivatives thereof. Examples of the glycol skeleton component include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, and 2,2-bis (4 '-Β-hydroxyethoxyphenyl) propane, isosorbate, 1,4-cyclohexanedimethanol and the like.

In the present invention, the thermoplastic and the layer of the resin film is made of polyethylene terephthalate, a layer of including consisting of cyclohexanedimethanol copolymerized polyester. More preferably, the thermoplastic resin film comprises a layer made of polyethylene terephthalate and a layer made of an ethylene terephthalate polycondensate having a copolymerization amount of cyclohexanedimethanol of 15 mol% or more and 60 mol% or less. By doing in this way, while having high reflective performance, the change of a reflective characteristic becomes small especially by heating, such as a bonding process.

  The thermoplastic resin film of the present invention includes a structure in which layers composed of a thermoplastic resin A (A layer) and layers composed of a thermoplastic resin B (B layer) are alternately laminated, and the A layer and the B layer are arranged in the thickness direction. It is preferable that there is a portion having a regularly laminated structure. That is, it is preferable that the order of arrangement in the thickness direction of the A layer and the B layer in the film of the present invention is not in a random state, and the order of arrangement of the third layer or more other than the A layer and the B layer is as follows. It is not particularly limited. In addition, in the case of having a C layer composed of an A layer, a B layer, and a thermoplastic resin C, they are laminated in a regular permutation such as A (BCA) n, A (BCBA) n, A (BABCBA) n. Is more preferable. Here, n is the number of repeating units. For example, in the case of A (BCA) n where n = 3, this indicates that the layers are stacked in a permutation of ABCABCABCA in the thickness direction.

  In the present invention, the thermoplastic resin film must have a lamination number of 50 layers or more. More preferably, the layers made of the thermoplastic resin A (A layer) and the layers made of the thermoplastic resin B (B layer) are alternated. The total number of layers is 50 or more. More preferably, each is 50 layers or more, and most preferably each is 80 layers or more. If the structure in which the A layer and the B layer are laminated by 25 layers or more is not included, sufficient reflectance cannot be obtained. Further, the upper limit is not particularly limited, but it is preferably 1500 layers or less in consideration of a decrease in wavelength selectivity accompanying a decrease in stacking accuracy due to an increase in the size of the device and an increase in the number of layers. .

  Here, the in-plane average refractive index difference between the A layer and the B layer is preferably 0.03 or more and 0.25 or less. More preferably, it is 0.05 or more, More preferably, it is 0.08 or more. When the refractive index difference is smaller than 0.03, a sufficient reflectance cannot be obtained, which is not preferable. Moreover, it is more preferable that the difference between the in-plane average refractive index of the A layer and the refractive index in the thickness direction is 0.03 or less because the angle dependency of the reflection band is reduced.

  In the present invention, it is preferable that at least one of the higher-order reflection bands has a reflectance of 30% or less. Here, the higher-order reflection band refers to the observed reflection peak on the highest wavelength side as the primary reflection peak, and the wavelength band X of the primary reflection peak is the order N (N is an integer of 2 or more). Each wavelength band X / N ± 25 nm obtained by dividing by. In addition, this ± 25 nm takes into consideration a measurement error and a peak reading error. Further, when at least one of the higher-order reflection bands has a reflectance of 30% or less, when the wavelength band X of the first-order reflection peak is composed of, for example, certain wavelength regions X1 to X2, in the section of X1 / N to X2 / N It means having at least one region having a reflectance of 30% or less. More preferably, at least one of the higher-order reflection band peaks has a reflectance of 20% or less, and more preferably has a reflectance of 15% or less. By having at least one higher-order reflection band having a reflectivity of 30% or less in this way, there is almost no coloration due to the higher-order reflection band, a decrease in color purity, or deterioration due to ultraviolet rays. It is suitable because it does not easily occur. Further, if the reflectance is 15% or less, the level is almost the same as that of the surface reflection, so that it is optimal with almost no effect on coloring or a decrease in color purity.

  Further, it is more preferable that the order of the higher-order reflection band of the present invention is 2nd order or more and 4th order or less. More preferably, it is 2nd order or more and 3rd order or less. If there is at least one second-order or fourth-order reflection peak band having a reflectance of 30% or less, coloring due to a higher-order reflection band and a decrease in color purity do not occur, which is not preferable.

Screen for the reflector of the present invention, the thickness unevenness in the longitudinal direction and / or width direction Ru der 5%. In such a case, color unevenness due to thickness variation does not become a problem, and the clarity of the film becomes good, so that a reflector is bonded together and the screen is not slack. Further, when the thickness variation in the longitudinal direction and / or the width direction of the reflector is subjected to Fourier transform analysis, the Pw value at a wave number of 1 to 100 (1 / m) is preferably 0.5 or less. More preferably, it is 0.3 or less. In such a case, in the screen, color unevenness can hardly be detected visually. Here, the method of analyzing the fluctuation cycle of the film thickness is preferably a method in which the film thickness is continuously measured and evaluated by performing Fourier transform (hereinafter referred to as “FFT treatment”) of the obtained data. Used. As for FFT processing, for example, “Mathematics of Engineer 1” first edition (Kyoritsu Publishing Co., Ltd. Kyoritsu Zensho 516) etc. about the theory of Fourier transform, “Optical Engineering” first edition (Kyoritsu Publishing Co., Ltd.) etc. about FFT processing techniques As described. Here, Pw is obtained by converting the thickness change data into an absolute value of the thickness, and using the data obtained by converting the average value so as to be the center value of the thickness change, by FFT processing. It is the spectral intensity Pwn at a certain wave number, which is determined by the following equation when the real part is an and the imaginary part is bn.
Pwn = 2 (an ² + bn ² ) ^1/2 / N
n: Wave number (m-1)
N: Number of measurements In the screen reflector of the present invention, the reflection band is preferably asymmetric with respect to the wavelength giving the maximum reflectance, and is tailed to the low wavelength side. This is because even if the incident angle of projection light from a projector or the like deviates from the vertical direction of the screen, it is difficult for the contrast to decrease. In order to do this, it is preferable to widen the flow path 1.1 to 2 times in the thickness direction at the die position opening when the feed block is stacked and then supplied to the die. By doing so, the thickness of the reflector surface layer is reduced, and as a result, the reflection peak tails to the low wavelength side.

  The screen reflector of the present invention preferably has a total light transmittance of not less than 400 nm and less than 700 nm of 50% or more. In such a case, high contrast can be obtained while improving the color purity. More preferably, the total light transmittance is 70% or more. In this case, a higher contrast can be obtained even under bright light. The total light transmittance is more preferably 80% or less. This is because when the total light transmittance is greater than 80%, a color change due to an angle is likely to occur, and sufficient contrast is difficult to obtain.

  The number of laminated thermoplastic resin films is 150 or more, substantially does not include an adhesive layer and an adhesive layer, and has a maximum reflectance of 60% or more in each band corresponding to RGB. Is preferred. The reflector does not include an adhesive layer or an adhesive layer, and is a thermoplastic resin film composed of 150 or more layers. Since each peak corresponding to RGB has a peak with a maximum reflectance of 60% or more, each of RGB It is not necessary to attach a reflector corresponding to the above, and scattering at the bonding interface is reduced, resulting in a higher definition display. Further, in each band corresponding to RGB, the peak top reflectance is preferably 60% or more, and the total light transmittance from 400 nm to less than 700 nm is preferably 50% or more. In this case, high contrast can be obtained while improving the color purity. Further, when the RGB reflectors are integrated, the total light transmittance is more preferably 75% or less. This is because when the total light transmittance is larger than 75%, a color change due to an angle is likely to occur, and it is difficult to obtain a sufficient contrast. Further, the number of stacked layers is preferably 400 layers or more and 1500 layers or less so that the maximum reflectance is 90% or more in each of the RGB bands.

  Moreover, in the reflector of this invention, it is preferable to have a layer which has a polyethylene terephthalate of 3 micrometers or more as a main component on at least one surface of a laminated film. More preferably, it has a layer mainly composed of polyethylene terephthalate of 5 μm or more. Further, it is more preferable to have a layer mainly composed of polyethylene terephthalate of 3 μm or more on both sides. If there is no layer made of polyethylene terephthalate having a thickness of 3 μm or more, the reflectance distribution becomes abnormal when the surface is scratched or the like, which is not preferable.

  In the reflector of the present invention, it is preferable that layers other than the outermost layer contain substantially no particles having an average particle diameter of 20 nm to 20 μm. When particles having an average particle diameter of 20 nm or more and 20 μm or less are contained in the laminated film, it is not preferable because transparency is deteriorated or diffuse reflection occurs. Moreover, it is not preferable because only the stacking accuracy causes a sagging and there is a possibility that the reflection performance is lowered.

  The reflector of the present invention includes an easy adhesion layer, an easy slip layer, a hard coat layer, an antistatic layer, an abrasion resistant layer, an antireflection layer, a color correction layer, a color absorbing layer, an electromagnetic wave shielding layer, and an ultraviolet absorbing layer. Functional layers such as a printing layer, a metal layer, a transparent conductive layer, a gas barrier layer, a hologram layer, a release layer, an adhesive layer, an adhesive layer, a diffusion layer, and a lens layer may be added.

  The screen of the present invention must be composed at least of the above-described reflector and absorber. With such a configuration, it is possible to provide a low-cost screen that is less likely to cause deterioration of reflection characteristics in an actual use environment and that has no color unevenness. The screen of the present invention is preferably composed of a reflector that reflects the bands corresponding to RGB and an absorber that absorbs the entire visible light band. In this case, since the projection light from the projector can be efficiently reflected and excess external light can be absorbed, the contrast is further improved.

  Moreover, the absorber in this invention is for absorbing the light which permeate | transmitted the reflector, and it is preferable that an absorber is a board | substrate containing a black film or a black paint. More preferably, the absorber has a thickness of 100 μm to 250 μm. When the absorber is thinner than 100 μm, warping may occur when the reflector is bonded under heating conditions, which is not preferable. On the other hand, the case of 250 μm or more is not preferable because the handling property is deteriorated.

  The screen of the present invention preferably includes a diffuser and / or a lens body. Here, the diffuser scatters the light reflected by the reflector, and this greatly improves the visual field characteristics. As the diffuser, glass having a diameter of about 1 μm to 5 mm, inorganic particles, a polymer dispersed therein, or a commercially available uneven structure is preferable. The lens body is for reducing the directivity of the light reflected by the reflector, adjusting the directivity of the light incident on the reflector, and suppressing the angle dependence due to the incident light. For example, there is a microlens film on which a two-dimensional microlens array is formed, and the microlens may be a convex lens, a concave lens, or a combination of both. The microlens only needs to be about the same as or smaller than the pixel size. For example, lenses having a diameter of about 0.1 mm may be densely arranged in the plane.

  Further, the screen of the present invention preferably has a protective film, and the protective film protects the diffuser and the reflector from the outside, and can improve the quality and durability of the screen.

  The screen of the present invention preferably includes a layer (polarizing layer) that allows only light in a specific vibration direction to pass therethrough. In this way, the polarization component of the external light incident on the screen can be partially cut by the polarizing layer, so that the contrast of the image can be increased. In this case, since the three primary color lights projected from a liquid crystal projector or the like are polarized light, by making the vibration direction the same as that of the polarizing filter layer, the light can be incident on the screen without being attenuated. An antireflection layer may be formed on the diffuser, the protective film, and the polarizing layer in order to suppress surface reflection.

  In the screen of the present invention, as a permutation of the arrangement of units constituting the screen, from the light incident surface side, a polarizing layer and / or a protective layer, a diffuser, a B reflector, a G reflector, an R reflector, and an absorption It is preferable that it is a body. In this case, the surface is hard to be scratched, the visual field characteristics are good, and it is difficult to be influenced by external light so that a high contrast can be obtained. In addition, since light having a shorter wavelength is more likely to be scattered, it is preferable that the B reflector is closer to the light incident side in order to reduce scattered light. Each of these units may be bonded with a commercially available adhesive or adhesive, and the diffuser or the surface protective layer may be formed on the surface of the reflector by coating.

  The screen of the present invention is suitable as a screen for a front type projector or a rear type projector, and is particularly suitable for a front type.

  Next, the preferable manufacturing method of the reflector of this invention is demonstrated below.

  Two types of thermoplastic resins A and B are prepared in the form of pellets. If necessary, the pellets are pre-dried in hot air or under vacuum and supplied to an extruder. In the extruder, the resin heated and melted to a temperature equal to or higher than the melting point is homogenized by a gear pump or the like, and foreign matter or denatured resin is removed through a filter or the like.

  The thermoplastic resin sent out from different flow paths using these two or more extruders is then sent into the laminating apparatus. As a laminating apparatus, a method of laminating in multiple layers using a multi-manifold die, a field block, a static mixer, or the like can be used. Moreover, you may combine these arbitrarily. Here, in order to efficiently obtain the effects of the present invention, a multi-manifold die or a feed block capable of individually controlling the layer thickness for each layer is preferable. Furthermore, in order to control the thickness of each layer with high accuracy, a feed block provided with fine slits for adjusting the flow rate of each layer by electric discharge machining or wire electric discharge machining with a machining accuracy of 0.1 mm or less is preferable. At this time, in order to reduce nonuniformity of the resin temperature, heating by a heat medium circulation method is preferable. Moreover, in order to suppress the wall resistance in the feed block, the roughness of the wall surface is preferably 0.4 S or less, or the contact angle with water at room temperature is 30 ° or more. By using such an apparatus, high stacking accuracy is achieved, so that it is easy to obtain a reflector having a maximum reflectance of 60% or more.

In order to achieve the maximum reflectance of 60% or more, which is the first feature of the present invention, the A layer and the B layer are alternately laminated by 25 or more layers, and the number of laminated layers is 50 or more. is important. Further, the layer thickness of each layer needs to be designed so as to obtain the desired reflection performance based on the following formula 1, and the in-plane average refractive index and the layer thickness are distributed within a range of 40% or less. Even if this occurs, it is acceptable. If there is a distribution larger than 40%, the half-value width of the reflection peak becomes too large, and there is a problem that contrast is lowered or color purity is lowered when a screen is formed. Moreover, in order that the maximum reflectance which is a more preferable aspect of this invention is 80% or more, it is preferable that it is 100 or more layers. Moreover, in order that the maximum reflectance which is a more preferable aspect of the present invention is 90% or more, the number of laminated layers is preferably 150 layers or more.
2 × (na · da + nb · db) = λ Equation 1
na: In-plane average refractive index of the A layer nb: In-plane average refractive index of the B layer da: Layer thickness (nm) of the A layer
db: Layer thickness of layer B (nm)
λ: main reflection wavelength (primary reflection wavelength)
In order to have at least one higher-order reflection band having a reflectance of 30% or less, which is one of the preferred embodiments of the present invention, most of the adjacent A layer and B layer satisfy the following formula 2. It is good to have a simple layer structure. In order to efficiently obtain the effect of the present invention, it is preferable that the following formula 2 is satisfied, but the in-plane average refractive index and the layer thickness are acceptable even if a deviation of 10% or less occurs. In order to have at least one higher-order reflection band having a reflectance of 15% or less, which is a preferred embodiment of the present invention, the layer thickness deviation is 5% or less, and the layer thickness deviation is adjacent. Rather than being regular between layers, it is preferable to be random. For a reflector with a large area, the maximum reflectance is 80% or more, and very high stacking accuracy is required to satisfy Equation 2, but such stacking accuracy is easily and stably achieved by the conventional method. It was impossible to do. In order to achieve such high lamination accuracy, 100 to 300 fine slits having a surface roughness of 0.1 S or more and 0.6 S or less, particularly in discharge wire processing with a processing accuracy of 0.01 mm or less. It is particularly preferable to laminate with a feed block. Further, even if Equation 2 is not satisfied, by using the special feed block as described above, the total light transmittance of 400 nm or more and less than 700 nm is obtained while the maximum reflectance is 60% or more in any of the RGB bands. % Or more can be achieved.
na · da = nb · db × (N−1) Equation 2
na: In-plane average refractive index of the A layer nb: In-plane average refractive index of the B layer da: Layer thickness (nm) of the A layer
db: Layer thickness of layer B (nm)
N: degree (integer of 2 or more)
In the present invention, it is preferable to adjust the thickness of each layer in the laminating apparatus so that the distribution range of the thickness ratio of the adjacent A layer and B layer in a certain cross section is 5% or more and 40% or less. More preferably, it is 10% or more and 30% or less. If the thickness ratio distribution is smaller than 5%, the repetition periodicity of the layer is too high, and high-order reflection is very likely to occur. Further, when it is larger than 40%, since the lamination accuracy is too low, not only the reflectance of the desired band is lowered, but also a reflection peak appears in an unexpected wavelength band, and the half width of the reflection peak becomes too large, When a screen is used, there are problems that the contrast is lowered and the color purity is lowered.

  In order to achieve the order of the higher-order reflection band having a reflectance of 30% or less, which is a preferred embodiment of the present invention, from 2nd to 4th, N in Formula 2 is 2 or more and 4 or less. Is preferred.

In the present invention, the distribution range of the maximum reflectance in the band corresponding to RGB within 1 m ² must be 20% or less. For this purpose, the stacking apparatus is as shown in FIGS. It is preferable to use at least a feed block having fine slits, and the number of slits is preferably 50 or more. Here, FIG. 1 is a conceptual plan view of each part of the feed block having the fine slit 3. FIG. 2 is a three-dimensional view thereof. 1 and 2, the thermoplastic resin A is supplied from the top of 2 and distributed to the slits 3b. Moreover, the thermoplastic resin B is supplied from the upper part of 4, and is distributed to the slit of 3a. And each resin which passed the slit merges and is laminated | stacked in a multilayer. Here, as the slit shape, as shown in FIG. 3, it is preferable that the slit area 6 on the thermoplastic resin supply surface side and the slit area 7 on the non-supply surface side are not the same. Further, (the slit area on the non-supply side of the thermoplastic resin) / (the slit area on the supply surface side) is preferably 50% or less. In this case, the distribution range can be easily made 10% or less. More preferably, the pressure loss in the feed block is 1 MPa or more, and further preferably the slit length (Z-direction slit length in the figure) is 100 mm or more. By these, it becomes easy to make a distribution range into 5% or less. It is also preferable to have a manifold corresponding to each slit inside the feed block. By these methods, the flow velocity distribution in the width direction (Y direction in the figure) inside the slit is made uniform, so that the lamination ratio in the width direction of the laminated films is also made uniform, and reflection within a large area. The rate distribution is small.

  The molten laminate thus obtained is then formed into a target shape by a die and then discharged. Here, as the die to be molded into a sheet shape, it is preferable that the widening ratio of the laminated body in the die is 1 to 100 times. More preferably, it is 1 to 50 times. When the width-expansion ratio of the laminated body in the die is larger than 100 times, the disturbance of the laminated thickness of the surface layer of the laminated body increases, which is not preferable. Since the widening rate of the laminated body in the die is 1 to 100 times, it becomes easy to reduce the maximum reflectance distribution range of the band corresponding to RGB to 10% or less, and to 400 to 700 nm. It is easy to set the light transmittance to 70% or more. In addition, in order to make the maximum reflectance distribution range of the band corresponding to RGB 5% or less, the flow path widening ratio in the film thickness direction is doubled in the flow path process in which the melt lamination flows in a laminar flow state. It is also preferable that: In this way, the total light transmittance can be 80% or more. Once the molten laminate laminated with high accuracy is widened in the flow path by more than twice in the thickness direction, the flow velocity in the surface layer becomes too larger than the flow velocity in the central portion, and the lamination thickness gradually increases in the film thickness direction. When an extremely inclined structure that changes is formed, and the width is increased in order to form the sheet into a sheet shape (the channel is expanded in the film width direction), the inclined structure of the laminate in the center in the width direction where the flow velocity is high is further expanded. For this reason, it is difficult for the resulting sheet to have a reflectance difference of 5% or less in the width direction.

  Further, the reflector which is a preferred embodiment of the present invention is a thermoplastic resin film which does not include an adhesive layer or an adhesive layer and has a laminate number of 150 layers or more, and has a peak top reflectance of 60% in each band corresponding to RGB. In order to obtain a reflector having a total light transmittance of not less than 400 nm and less than 700 nm of 50% or more, it is preferable to use a feed block as shown in FIGS. FIG. 4 shows a feed block composed of three independent fine slit portions, and each fine slit portion has a stack that becomes a reflector corresponding to R, G, and B, respectively. The thermoplastic resin A is supplied to 9 and 13, and is distributed to the 10, 12, and 14 fine slit portions. Further, the thermoplastic resin B is supplied to 11 and 15, and is distributed to the fine slit portions of 10, 12, and 14. The shape of the slit is as shown in FIG. 3, and the preferred form is as described above. Further, FIG. 5 is a view in which the laminated fluids laminated at the respective fine slits are joined and further integrated. The thermoplastic resin laminate laminated at the fine slit portion 10 is supplied to the 17A portion, from 12 to the 17B portion, and from 14 to the 17C portion to be integrated. Conventionally, when the number of stacked layers is 300 layers or more, a static mixer is used in combination with a feed block of about 200 layers, but it is possible to obtain a reflector having a reflection peak with a narrow half-value width in each of the R, G, and B bands. could not. This is because, in order to obtain a band corresponding to R, G, and B, the layers must be made of laminates having different layer thicknesses. When a static mixer is used, the layer thickness gradually changes, and half This is because the price range widens. In addition, if only a feed block as shown in FIG. 1 is used without using a mixer, the layer thickness cannot be controlled due to a modified polymer due to thermal deterioration or the length in the X direction is too long. .

  And the sheet | seat laminated | stacked in the multilayer discharged | emitted from die | dye is extruded on cooling bodies, such as a casting drum, and is cooled and solidified, and a casting film is obtained. At this time, using a wire-like, tape-like, needle-like or knife-like electrode, it is brought into close contact with a cooling body such as a casting drum by electrostatic force and rapidly cooled and solidified, or from a slit-like, spot-like, or planar device. A method in which air is blown out and brought into close contact with a cooling body such as a casting drum and rapidly cooled and solidified, and a method in which the nip roll is brought into close contact with the cooling body and rapidly solidified is preferable. In particular, in the Fourier analysis of thickness variation, in order to set the Pw value at a wave number of 1 to 100 (1 / m) to 0.5 or less, a tape-like electrode is used and a cooling body such as a casting drum is applied by electrostatic force. A method of close contact and rapid solidification is preferred.

  Here, when making the casting film, if the die lip gap is adjusted and the draft ratio (lip gap / casting film thickness) is 15 or less, the thickness unevenness in the longitudinal direction and / or the width direction can be easily set to 5% or less. In addition, when the Fourier transform analysis is performed on the thickness variation in the longitudinal direction and / or the width direction of the reflector, the Pw value at a wave number of 1 to 100 (1 / m) can be easily set to 0.5 or less. preferable. Further, it is more preferable that the melt viscosity at 270 ° C. of the thermoplastic resin A and / or the thermoplastic resin B is 3200 poise or more and the resin temperature is 275 ° C. or less because the Pw value is easily 0.3 or less.

  The casting film thus obtained is preferably biaxially stretched as necessary. Biaxial stretching refers to stretching in the longitudinal direction and the width direction. Stretching may be performed sequentially biaxially or simultaneously in two directions. Further, the film may be redrawn in the longitudinal and / or width direction. In particular, in the present invention, it is preferable to use simultaneous biaxial stretching from the viewpoint of suppressing in-plane orientation difference and suppressing surface scratches.

  First, the case of sequential biaxial stretching will be described. Here, stretching in the longitudinal direction refers to stretching for imparting molecular orientation in the longitudinal direction to the film, and is usually performed by a difference in peripheral speed of the roll, and this stretching may be performed in one step. Alternatively, a plurality of roll pairs may be used in multiple stages. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +100 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The uniaxially stretched film thus obtained is subjected to surface treatment such as corona treatment, flame treatment, and plasma treatment as necessary, and then functions such as slipperiness, easy adhesion, and antistatic properties are provided. It may be applied by in-line coating.

  The stretching in the width direction refers to stretching for giving the film an orientation in the width direction. Usually, the tenter is used to convey the film while holding both ends of the film with clips, and the film is stretched in the width direction. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The biaxially stretched film is preferably subjected to a heat treatment at a temperature not lower than the stretching temperature and not higher than the melting point in the tenter in order to impart flatness and dimensional stability. After being heat-treated in this way, it is gradually cooled down uniformly, then cooled to room temperature and wound up. Moreover, you may use a relaxation process etc. together in the case of annealing from heat processing as needed.

  Next, the case of simultaneous biaxial stretching will be described. In the case of simultaneous biaxial stretching, the difference between the maximum value and the minimum value of the peak top reflectance in the band corresponding to RGB in the screen area is easily set to 20% or less, which is preferable. In the case of simultaneous biaxial stretching, the resulting cast film is subjected to surface treatment such as corona treatment, flame treatment, and plasma treatment as necessary, and then, such as slipperiness, easy adhesion, antistatic properties, etc. The function may be imparted by in-line coating.

  Next, the cast film is guided to a simultaneous biaxial tenter, and conveyed while holding both ends of the film with clips, and stretched in the longitudinal direction and the width direction simultaneously and / or stepwise. As simultaneous biaxial stretching machines, there are pantograph method, screw method, drive motor method, linear motor method, but it is possible to change the stretching ratio arbitrarily and drive motor method that can perform relaxation treatment at any place or A linear motor system is preferred. Although the stretching magnification varies depending on the type of resin, it is usually preferably 6 to 50 times as the area magnification. When polyethylene terephthalate is used as one of the resins constituting the laminated film, the area magnification is 8 to 30 times. Is particularly preferably used. In particular, in the case of simultaneous biaxial stretching, it is preferable to make the stretching ratios in the longitudinal direction and the width direction the same and to make the stretching speeds substantially equal in order to suppress the in-plane orientation difference. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The film thus biaxially stretched is preferably subsequently subjected to a heat treatment not less than the stretching temperature and not more than the melting point in the tenter in order to impart flatness and dimensional stability. In order to suppress the distribution of the main alignment axis in the width direction during this heat treatment, it is preferable to perform a relaxation treatment in the longitudinal direction immediately before and / or immediately after entering the heat treatment zone. After being heat-treated in this way, it is gradually cooled down uniformly, then cooled to room temperature and wound up. Moreover, you may perform a relaxation | loosening process in a longitudinal direction and / or the width direction at the time of annealing from heat processing as needed.

  In addition, in the present invention, when used in a large area such as a screen, an instantaneous spectroscope is installed in the width direction before the winding portion of the film forming process so as not to cause a problem as uneven color, and the reflection characteristics in the width direction. Preferably, the distribution is measured in-line, and the measurement result is fed back to the operation of the die lip gap adjusting bolt. By doing so, color unevenness in the width direction can be greatly reduced. Here, it is more preferable to feedback-control the measurement result of the conventional non-contact thickness meter together with the feedback control of the reflection characteristic. By doing so, it becomes easy to obtain a reflector for a screen that has no color unevenness and good flatness and is easy to bond.

An evaluation method of physical property values used in the present invention will be described.
(Method for evaluating physical properties)
(1) Lamination Thickness, Number of Laminations The layer configuration of the film was determined by observation with an electron microscope for a sample cut out of a cross section using a microtome. That is, using a transmission electron microscope HU-12 (manufactured by Hitachi, Ltd.), the cross section of the film was magnified 40000 times, a cross-sectional photograph was taken, and the layer structure and each layer thickness were measured. The embodiment of the present invention was not carried out because a sufficient contrast was obtained, but the contrast may be increased by using a known dyeing technique using RuO ₄ or OsO ₄ depending on the combination of thermoplastic resins used.

(2) Reflectance A Φ60 integrating sphere 130-0632 (Hitachi Ltd.) and a 10 ° inclined spacer were attached to a spectrophotometer (U-3410 Spectrophotometer) manufactured by Hitachi, Ltd., and the reflectance was measured. The band parameter was set to 2 / servo, the gain was set to 3, and the range from 187 nm to 2600 nm was set to 120 nm / min. Measured at a detection speed of. In order to standardize the reflectance, an attached Al ₂ O ₃ plate was used as a standard reflecting plate. The maximum reflectance in Table 1 is the measurement result at a location corresponding to the center of the screen. Also,. The distribution range is the result of measurement at the center and four corners in 1 m ² .

(3) Intrinsic viscosity Calculated from the solution viscosity measured at 25 ° C in orthochlorophenol. The solution viscosity was measured using an Ostwald viscometer. The unit is [dl / g]. The n number was 3, and the average value was adopted.

(4) Film thickness fluctuation The thickness thickness unevenness and the width direction thickness unevenness were measured using an Anritsu Co., Ltd. film thickness tester “KG601A” and an electronic micrometer “K306C”. Regarding the thickness unevenness in the longitudinal direction, the thickness of a film sampled 30 mm wide and 10 m long was continuously measured. In the width direction, the thickness was continuously measured for a length of 1 m. The film thickness unevenness was obtained by dividing the difference between the maximum thickness and the minimum thickness within the measured range by the average thickness and multiplying by 100 (%). In addition, about this film thickness nonuniformity, it measured by n number 5 times.

(5) Fourier analysis of longitudinal thickness variation of film At the time of measuring the longitudinal thickness variation described above, the output from the electronic micrometer was digitized using KEYENCE “NR-1000” and incorporated into a computer. The sampling rate and the winding speed were adjusted so that the data was sampled at 1024 points at a measurement length of 10 m. The numerical data taken in this way was converted into a quantitative thickness using Microsoft Excel 2000), and a Fourier transform (FFT) process was performed on the thickness variation. At this time, the thickness change data was converted into an absolute value of the thickness, and the average value was converted to the center value of the thickness change and used for analysis. At this time, if the length (m) of the film is taken as a variable in the flow direction, an intensity distribution with respect to the wave number (1 / m) can be obtained by FFT processing. Here, the obtained real part a _n, when the imaginary part and b _n, spectral intensity Pw ⁿ can be expressed as the following equation.
^{_{Pw n = 2 (a n 2}} + b n 2) 1/2 / N
n: Wave number (m ^-1 )
N: 1024 (number of measurements).

(6) Total light transmittance Using a spectrophotometer (U-3410 Spectrophotometer) manufactured by Hitachi, Ltd., transmittance in the range of 400 nm to 700 nm was measured in the transmission mode. The transmittance for each wavelength (every 1 nm) was added and divided by the number of measurement points (number of wavelength points) to calculate a transmittance average value in the range of 400 nm to 700 nm to obtain the total light transmittance (%). The band parameter was set to 2 / servo, the gain was set to 3, and the range from 187 nm to 2600 nm was set to 120 nm / min. Measured at a detection speed of.

( Comparative Example 2 )
1. Manufacturing method example of R reflector Thermoplastic resin A and thermoplastic resin B were prepared as two types of thermoplastic resins. In Example 1, polyethylene terephthalate (PET) [Toray F20S] having an intrinsic viscosity of 0.65 was used as the thermoplastic resin A. The melt viscosity of this PET at 270 ° C. was 2600 poise. Further, as a thermoplastic resin B, polyethylene terephthalate (CHDM copolymerized PET) obtained by copolymerizing 30 mol% of cyclohexanedimethanol with ethylene glycol (PETG6763 manufactured by Eastman) and polyethylene terephthalate having an intrinsic viscosity of 0.65 at a weight ratio of 85:15. A resin kneaded and alloyed with a twin-screw extruder was used. The melt viscosity at 270 ° C. of this raw material was 4500 poise. These thermoplastic resins A and B were each dried and then supplied to an extruder. The resin temperature was 270 ° C.

  Thermoplastic resins A and B were each melted at 270 ° C. by an extruder, passed through a gear pump and a filter, and then joined by a feed block having 201 fine slits as shown in FIG. A structure in which 101 layers of A and 100 layers of thermoplastic resin B are alternately stacked in the thickness direction was used. The slit shape of the feed block was 45% (slit area on the thermoplastic resin non-supply side) / (slit area on the supply side), and the slit length was 100 mm. In addition, both surface layer parts were made to become the thermoplastic resin A. The thickness of each layer is adjusted by the gap between fine slits (formed at a processing accuracy of 0.01 mm) in the feed block and the discharge amount of each resin. The thermoplastic resin A layer has a thickness of 97 nm in the stretched and heat-treated film. The plastic resin B layer was designed to be 102 nm. Here, the thickness ratio of the adjacent A layer and B layer (A layer thickness / B layer thickness) was set to 0.95. The laminate composed of a total of 201 layers thus obtained was supplied to a T-die and formed into a sheet shape (draft ratio 10), and then applied with static electricity (DC voltage 8 kV) using a tape-like electrode. And rapidly solidified on a casting drum kept at a surface temperature of 25 ° C.

  The obtained cast film was heated with a roll group set at 90 ° C. and stretched 3.4 times in the longitudinal direction, and then both surfaces of this uniaxially stretched film were subjected to corona discharge treatment in the air, and the wetting tension of the base film 55 mN / m, and the treated surface is coated with a laminated film coating solution composed of (polyester resin with a glass transition temperature of 18 ° C.) / (Polyester resin with a glass transition temperature of 82 ° C.) / Silica particles with an average particle size of 100 nm. Then, a transparent, easy-slip, and easy-adhesion layer was formed.

This uniaxially stretched film was guided to a tenter, preheated with hot air at 100 ° C., and then stretched 3.7 times in the width direction. The stretched film was directly heat-treated with hot air at 230 ° C. in a tenter, subsequently subjected to a relaxation treatment of 5% in the width direction at the same temperature, and then gradually cooled to room temperature and wound up. In addition, a width direction scanning β-ray thickness meter and an instantaneous spectrometer that measures the reflection characteristics at 10 points in the width direction in-line are installed before winding, and the thickness distribution data and reflection obtained by measuring them are measured. Based on the data of the rate distribution, feedback was applied to the die lip gap adjustment. The resulting film had a thickness of 20 μm and was cut for a 2.25 m ² screen. The obtained results are shown in Table 1.

2. Example of manufacturing G reflector
In Comparative Example 2 , a film was formed under the same apparatus and conditions except that the film forming speed was adjusted to set the film thickness to 16.5 μm. Further, the obtained film was cut for a 2.25 m ² screen. The obtained results are shown in Table 1.

3. Example of manufacturing B reflector
In Comparative Example 2 , a film was formed under the same apparatus and conditions except that the film forming speed was adjusted so that the film thickness was 14 μm. Further, the obtained film was cut for a 2.25 m ² screen. The obtained results are shown in Table 1.

4). Screen production example 1
The obtained B reflector, G reflector, R reflector and “Lumilar” X30, which is a black biaxially stretched PET film having a thickness of 188 μm, were bonded together with an acrylic adhesive. In addition, it bonded together so that it might become in order of B reflector, G reflector, R reflector, and X30 from the projection surface side. Further, a 19 μm mat film “Lumirror” X42 as a diffuser was bonded to the surface (projection surface side) of the B reflector with an acrylic adhesive. Furthermore, for reinforcement, it was bonded to a woven fabric to obtain a 2.25 m ² reflective screen. The obtained screen had high contrast and color purity even under bright light, and there was no color unevenness in the screen. Moreover, even if it wound up and stored repeatedly, neither a defect nor a bright spot due to breakage of the reflector occurred.

(Example 1 )
1. From the BGR reflector projection surface side, 201 layers are alternately laminated (B reflection portion) with 68 nm of A layer and 72 nm of B layer (B reflection portion), and then 201 layers are alternately laminated (G reflection portion) with 80 nm of A layer and 84 nm of B layer. A film was formed under the same conditions and apparatus as in Comparative Example 2 except that a 603-layer feed block as shown in FIG. 4 was used so that 201 layers (R reflection portion) could alternately be formed with 97 nm A layer and 102 nm B layer. . However, the shape of the fine slit is (slot area on the non-feeding side of the thermoplastic resin) / (slit area on the supply side) is 40%, the slit length is 160 mm, and the pressure loss in the feed block is 3 MPa. The slit gap and discharge rate were designed. The draft ratio was 5. The results are shown in Table 1 for the obtained integrated BGR reflector. The thickness of the BGR reflector was 50.5 μm and was cut for a 2.25 m ² screen.

2. Screen production example 2
The obtained BGR reflector and “Lumilar” X30, which is a black biaxially stretched PET film having a thickness of 188 μm, were bonded together with an acrylic adhesive. In addition, it bonded together with X30 so that the projection surface side might become a B reflection layer. Further, a 19 μm mat film “Lumirror” X42 serving as a diffuser was bonded to the surface (projection surface side) of the B reflection layer with an acrylic adhesive. Furthermore, for reinforcement, it was bonded to a woven fabric to obtain a 2.25 m ² reflective screen. In this case, since the number of times of bonding was reduced, defects due to air entrainment during bonding and poor flatness were less likely to occur, and scattering by the adhesive layer was suppressed, resulting in higher definition than in Example 1. The obtained screen had high contrast and color purity even under bright light, and there was no color unevenness in the screen. Moreover, even if it wound up and stored repeatedly, neither a defect nor a bright spot due to breakage of the reflector occurred.

( Comparative Example 3 )
1. Example of manufacturing method of R reflector, G reflector, B reflector In comparative example 2, (non-supply side slit area) / (supply side slit area) is 60%, slit length is 80 mm, and the pressure loss in the feed block is The apparatus and conditions were the same as in Comparative Example 2 except that the pressure was 0.9 MPa. The obtained results are shown in Table 1.

2. Screen production example 3
A screen was prepared in the same manner as in Comparative Example 2 using the R reflector, G reflector, and B reflector obtained in Comparative Example 3 . The obtained screen had high contrast under bright light and high color purity, and although slight color unevenness was observed at the edge of the screen, there was no problem. Moreover, even if it wound up and stored repeatedly, neither the fault nor the bright spot by damage to a reflector generate | occur | produced.

( Comparative Example 4 )
1. Production example of R reflector, G reflector, B reflector
In Comparative Example 2 , the draft ratio was set to 19, and the reflectance distribution data was not fed back by the instantaneous spectrometer. The obtained results are shown in Table 1.

2. Screen production example 4
A screen was prepared in the same manner as in Comparative Example 2 using the R reflector, G reflector, and B reflector obtained in Comparative Example 4 . Since the thickness unevenness of the reflector is somewhat large, air tends to be easily generated when the screen is pasted, as compared with Comparative Example 2 , and the handling property is slightly deteriorated. On the other hand, color irregularities with a slight periodicity were also observed, but the contrast and color purity under bright light were high, and no defects or bright spots due to damage to the reflector occurred even after repeated winding and storage. .

(Comparative Example 1)
1. Production Example of BGR Reflector-Absorber The following thin films were formed by sputtering on the surface of “Lumirror” X30, which is a black biaxially stretched PET film having a thickness of 250 μm.
High refractive index layer: ZnS (refractive index 2.4, thickness 611 nm, 4 layers)
Low refractive index layer: MgF ₂ (refractive index 1.4, thickness 1047 nm, 3 layers)
2. Screen production example 5
A 19 μm mat film “Lumirror” X42 serving as a diffuser was bonded to the BGR reflector-absorber prepared in Comparative Example 1 with an acrylic adhesive. Furthermore, for reinforcement, it was bonded to a woven fabric to obtain a 2.25 m ² reflective screen. The obtained screen had high contrast and color purity even under bright light, and there was no color unevenness in the screen. However, repeated winding and storage caused many defects and bright spots due to breakage of the reflector, and the image quality gradually deteriorated.

  The present invention is used for a screen reflector and a screen. More specifically, the present invention is suitably used for a screen that displays an image by receiving light from a light source and a screen reflector.

It is the top view which looked at the feed block from the Y direction. It is a three-dimensional perspective view of a feed block. It is the top view and enlarged 3D perspective view which looked at the fine slit part from the opposite side along the Y-axis. It is a three-dimensional perspective view of a feed block. It is the top view seen from the Y direction and Z direction of a confluence | merging part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Side plate 2 Thermoplastic resin A supply part 3 Slit part 3a, 3b Slit 4 Thermoplastic resin B Supply part 5 Side plate 6 Fluid supply surface side of a slit 7 Fluid non-supply surface side of a slit 8 Side plate 9 Thermoplastic resin A supply part 10 Slit part 11 Thermoplastic resin B supply part 12 Slit part 13 Thermoplastic resin A supply part 14 Slit part 15 Thermoplastic resin B supply part 16 Side plate 17 Junction device

Claims (8)

A side plate, a thermoplastic resin A supply part, a slit part, a thermoplastic resin B supply part, a slit part, a thermoplastic resin A supply part, a slit part, a thermoplastic resin B supply part, and a side plate are provided in this order. Each of the slit portions has a plurality of slits, and each slit portion has the thermoplastic resin A from the adjacent thermoplastic resin A supply portion, and the thermoplastic resin B from the adjacent thermoplastic resin supply portion B has the slit. The slit shape of each slit portion is (slit area on the non-supply surface side) / (slit area on the supply surface side) ≦ 50%. that by using a full Idoburokku draft ratio (lip gap / casting film thickness) was obtained as 15 or less, the layer and Shikurohe consisting port triethylene terephthalate (thermoplastic resin a) Sanji is methanol copolymerized polyester (thermoplastic resin B) respectively stacked 25 layers or more layers alternately made of and number of layers to fit 50 or more, a polyester film that reflects a bandwidth corresponding to RGB, the RGB A reflector for a screen, wherein the maximum reflectance is 60% or more and the thickness unevenness in the longitudinal direction and / or the width direction is 5% or less in any of the corresponding bands. 2. The screen reflector according to claim 1, wherein the reflection band is asymmetric with respect to a wavelength giving the maximum reflectance, and is tailed on a low wavelength side. The number of laminated thermoplastic resin films is 150 or more, substantially does not include an adhesive layer and an adhesive layer, and has a maximum reflectance of 60% or more in each band corresponding to RGB. 2. A reflector for a screen according to 2. The reflector for a screen according to any one of claims 1 to 3, wherein the total light transmittance from 400 nm to less than 700 nm is 50% or more. The screen containing the reflector and absorber in any one of Claims 1-4 at least. The screen according to claim 5, comprising a diffuser and / or a lens body. The screen according to claim 5 or 6, comprising a polarizing layer. The screen according to claim 5, wherein the absorber has a thickness of 100 μm to 250 μm.

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