EP1652001A1 - Ecran de retroprojection resistant aux rayures et son procede de production - Google Patents

Ecran de retroprojection resistant aux rayures et son procede de production

Info

Publication number
EP1652001A1
EP1652001A1 EP04719963A EP04719963A EP1652001A1 EP 1652001 A1 EP1652001 A1 EP 1652001A1 EP 04719963 A EP04719963 A EP 04719963A EP 04719963 A EP04719963 A EP 04719963A EP 1652001 A1 EP1652001 A1 EP 1652001A1
Authority
EP
European Patent Office
Prior art keywords
rear projection
particles
projection screen
screen according
scattering
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP04719963A
Other languages
German (de)
English (en)
Inventor
Markus Parusel
Jann Schmidt
Herbert Groothues
Christoph Krohmer
Günther DICKHAUT-BAYER
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Roehm GmbH Darmstadt
Original Assignee
Roehm GmbH Darmstadt
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Roehm GmbH Darmstadt filed Critical Roehm GmbH Darmstadt
Priority to EP08168820A priority Critical patent/EP2339398A1/fr
Publication of EP1652001A1 publication Critical patent/EP1652001A1/fr
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B30/00—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images
    • G02B30/50—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images the image being built up from image elements distributed over a 3D volume, e.g. voxels
    • G02B30/56—Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images the image being built up from image elements distributed over a 3D volume, e.g. voxels by projecting aerial or floating images
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/021—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures
    • G02B5/0221—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures the surface having an irregular structure
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/0236—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element
    • G02B5/0242—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element by means of dispersed particles
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0273—Diffusing elements; Afocal elements characterized by the use
    • G02B5/0278—Diffusing elements; Afocal elements characterized by the use used in transmission
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0273—Diffusing elements; Afocal elements characterized by the use
    • G02B5/0294—Diffusing elements; Afocal elements characterized by the use adapted to provide an additional optical effect, e.g. anti-reflection or filter
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/54—Accessories
    • G03B21/56—Projection screens
    • G03B21/60—Projection screens characterised by the nature of the surface
    • G03B21/62—Translucent screens

Definitions

  • the present invention relates to scratch-resistant rear projection screens comprising at least one light-scattering polymethyl methacrylate layer, process for producing these rear projection screens and use.
  • Back projection technology can be used to make information accessible to a wide audience.
  • the construction of such a system consists of an imaging surface that is illuminated from the back with a projector and thus provides the information.
  • This technique takes place e.g. Use in control rooms (power plants, rail traffic) to make it easier for those responsible to keep track of the complex processes so that control errors can be avoided.
  • Another application is scoreboards in e.g. Sports stadiums and motor racing races. Here, the course and status of the event is communicated to the viewers, even if they are at a greater distance from the actual events.
  • This type of information transfer is also used in, for example, TV sets, open-plan and home cinemas, but also as an advertising medium at trade fairs, in shop windows and shops. Furthermore, this technology is also used to transmit information in presentations and in flight simulators, where the virtual environment is mapped as realistically as possible on the cockpit panes.
  • rear projection panels and foils which have scattering media, such panels containing particles with a refractive index different from the matrix.
  • the panels and foils are also suitable for rear projection, but do not combine the entire range of the requirement profile, so that only a part of the requirements for a screen are met.
  • the projection surfaces must, for example, have a very quiet, clear and high-resolution image reproduction because the viewer has to record the information over a longer period of time (example: control room, home cinema, etc.).
  • known scattering media such as barium sulfate and titanium dioxide can be used to produce plates and foils which have a high light scattering angle.
  • the resolution of the projection is also high. Accordingly, the viewing angle of the image should also be correspondingly high.
  • the image sharpness of the projection plates are suboptimal, with the other requirements, for example scratch sensitivity, not meeting many requirements.
  • Umbrellas are also known which contain plastic particles as scattering media.
  • Document JP11179856 describes multilayer boards with at least one layer which comprises a polymethyl methacrylate matrix and crosslinked polymethyl methacrylate beads as scattering / matting agents, the proportion of the beads being in the range from 0.5 to 25% by weight.
  • the beads have a size in the range from 3 to 30 ⁇ m, with only 2 mm thick plates being described in the examples, which contain about 3% by weight of scattering beads with a size of about 6 ⁇ m.
  • the problem with these screens is their scratch sensitivity.
  • JP 07234304 describes a mixture of crosslinked acrylate / styrene beads (14 ⁇ m) in a transparent plastic. A disadvantage of these umbrellas is that scratches are very noticeable visually.
  • disks are known which comprise mixtures of particles.
  • JP 4-134440 describes plates in which two types of particles are used, the particle size and refractive index difference of the matrix having to be coordinated with one another, as a result of which the wavelength-selective scattered light (small particles scatter blue light more strongly, large particles red light) on the particles is canceled out. The scatter plates are characterized by a neutral color.
  • panes are known which can be used for lighting applications.
  • Such discs are set out, for example, JP 8-198976, JP 5-51480 and JP 2000-296580.
  • a disadvantage of the previously described plates is, on the one hand, their suboptimal image quality and a high scratch sensitivity of the screen.
  • the document EP-A-0 561 551 describes a multilayer plate with a scattering layer made of a mixture of a transparent polymer and spherical particles (2-15 ⁇ m). These umbrellas are also very sensitive to scratching.
  • a problem with known rear projection screens provided with scattering media is therefore that their imaging properties are not optimal with regard to their scratch sensitivity.
  • the known screens have a relatively low image sharpness or a relatively unfavorable brightness distribution.
  • many umbrellas do not meet the mechanical requirements, scratches in particular having an optically disadvantageous effect.
  • the screens should allow high definition and resolution of the projected image.
  • Another object of the present invention was to provide rear projection screens which have a particularly uniform brightness distribution.
  • the rear projection screens should have the highest possible mechanical stability. Scratches on the screen should not be visible or only slightly. In particular, damage should have little or no influence on the imaging ability of the screen.
  • the invention was based on the object of providing rear projection screens which can be produced particularly easily.
  • the rear projection screens should be able to be produced in particular by extrusion.
  • the images on the rear projection screens should be particularly rich in contrast.
  • Another object of the invention was that the rear projection screens have a high durability, in particular a high resistance to UV radiation or weathering.
  • the present invention was also based on the object of providing rear projection screens which, based on their imaging properties, only reflect to a small extent.
  • the size of the screens should be able to be adapted to the respective requirements.
  • the thickness of the rear projection screens should be able to be adapted to any requirements without the image quality and the scratch sensitivity being adversely affected thereby.
  • the concentration of the spherical scattering particles (A) c PA , the thickness of the light-scattering polymethyl methacrylate layer ds and the particle size of the spherical scattering particles (A) DA SO are selected, the ratio c PA * ds / Dp A 3 is in the range of 0.001 to 0.015% by weight * mm / ⁇ m 3 , the concentration of the spherical particles (B) c PB , the thickness of the light-scattering polymethyl methacrylate layer ds and the particle size of the spherical particles (B) DPB is chosen so that the ratio cp B * ds Dp B 3 in the range from 0.000005 to 0.002% by weight * mm / ⁇ m 3 and the ratio of the square of the average surface roughness of the polymethyl methacrylate layer Rz to the third power of the particle size
  • the rear projection screens of the present invention can be adapted to individual needs without the image quality and / or the scratch sensitivity being impaired thereby.
  • the rear projection screens of the present invention allow high definition and resolution of the projected image.
  • the rear projection screens made available according to the present invention have a particularly uniform brightness distribution.
  • the rear projection screens of the present invention show high mechanical stability. Scratches are not or only slightly visible on the screen.
  • images projected onto the rear projection screens according to the invention are very quiet. As a result, displays can be viewed without fatigue over a long period of time.
  • the rear projection screens of the present invention show a non-glossy, matt surface profile.
  • the shape of the surface structure can be adjusted differently without affecting the optical parameters, apart from the gloss. This can reduce reflections that adversely affect the image on the screen.
  • the rear projection screens of the present invention can be manufactured particularly easily.
  • the rear projection screens can be produced in particular by extrusion.
  • the rear projection panels according to the invention show a high resistance to weathering, in particular to UV radiation.
  • the size and shape of the rear projection screens can be adapted to the needs.
  • the light-scattering polymethyl methacrylate layer of the rear projection screen according to the present invention has 1 to 60% by weight, in particular 3 to 55% by weight and preferably 6 to 48% by weight, based on the weight of the light-scattering polymethyl methacrylate layer, of spherical scattering particles (A) and spherical particles (B).
  • the scattering particles (A) and the particles (B) are spherical.
  • the term spherical in the context of the present invention denotes that the particles preferably have a spherical shape, it being obvious to the person skilled in the art that, due to the production methods, particles with a different shape may also be present, or that the shape of the particles may differ from the ideal spherical shape ,
  • the term spherical means that the ratio of the largest dimension of the particles to the smallest dimension is a maximum of 4, preferably a maximum of 2, these dimensions being measured in each case by the center of gravity of the particles. At least 70, particularly preferably at least 90%, based on the number of particles, is preferably spherical.
  • the scattering particles (A) have an average particle size V 50 in the range from 0.1 to 40 ⁇ m, in particular from 1 to 35 ⁇ m, preferably 2 to 30 ⁇ m, preferably 3 to 25 ⁇ m, in particular 4 to 20 ⁇ m and particularly preferably 5 to 15 ⁇ m.
  • Such particles are known per se and can be obtained commercially. These include, in particular, plastic particles and particles made of inorganic materials, such as aluminum hydroxide, aluminum-potassium silicate (mica), aluminum silicate (kaolin), barium sulfate (BaSO 4 ), calcium carbonate, magnesium silicate (talc). Of these, plastic particles are particularly preferred.
  • inorganic materials such as aluminum hydroxide, aluminum-potassium silicate (mica), aluminum silicate (kaolin), barium sulfate (BaSO 4 ), calcium carbonate, magnesium silicate (talc).
  • plastic particles are particularly preferred.
  • the plastic particles that can be used according to the invention are not particularly limited.
  • the type of plastic from which the plastic particles are produced is largely uncritical, with the light refraction taking place at the phase boundary of the plastic beads with the matrix plastic.
  • the refractive index of the plastic particles has a refractive index n 0 measured at the Na-D line (589 nm) and at 20 ° C., which differs from the refractive index n 0 of the matrix plastic by 0.02 to 0.2 units.
  • the spherical scattering particles (A) preferably comprise crosslinked polystyrene, polysilicon and / or crosslinked poly (meth) acrylates.
  • a group of preferred plastic particles that are used as scattering agents contain silicones. Such particles are obtained, for example, by hydrolysis and polycondensation of organotrialkoxysilanes and / or tetraalkoxysilanes, which have the formulas
  • organotrialkoxysilanes are methyltrimethoxysilane, methyltriethoxysilane, methyl-n-propoxysilane, methyltriisopropoxysilane and methyltris (2-methoxyethoxy) silane.
  • Spreading agents made of silicone that are particularly preferably used in the present invention are available from GE Bayer Silicones under the trade names TOSPEARL® 120 and TOSPEARL® 3120.
  • Another group of preferred plastic particles are composed of: b1) 25 to 99.9 parts by weight of monomers which have aromatic groups as substituents, such as styrene, ⁇ -methylstyrene, ring-substituted styrenes, phenyl (meth) acrylate, benzyl (meth ) acrylate, 2-phenylethyl (meth) acrylate, 3-phenylpropyl (meth) acrylate or vinyl benzoate; and b2) 0 to 60 parts by weight of an acrylic and / or methacrylic acid ester with 1 to 12 carbon atoms in the aliphatic ester radical, which can be copolymerized with the monomers b1), examples of which are: methyl (meth) acrylate, ethyl ( meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acryl
  • Mixtures from which the plastic particles are produced particularly preferably have at least 80% by weight of styrene and at least 0.5% by weight of divinylbenzene.
  • the scattering particles can be produced by emulsion polymerization, as described, for example, in EP-A 342 283 or EP-A 269 324, very particularly preferably by polymerization in the organic phase, as described, for example, in German patent application P 43 27 464.1, with the latter Polymerization technology particularly narrow particle size distributions or, in other words, particularly small deviations of the particle diameter from the average particle diameter occur.
  • Plastic particles are particularly preferably used which have a temperature resistance of at least 200 ° C., in particular of at least 250 ° C., without this being intended to impose a restriction.
  • temperature-resistant means that the particles are essentially not subject to thermal degradation. Thermal degradation leads to undesirable discoloration, so that the plastic material is unusable.
  • Particularly preferred particles are available, among others, from Sekisui under the trade names ⁇ Techpolymer SBX-6, ⁇ Techpolymer SBX-8 and ⁇ Techpolymer SBX-12.
  • the previously described scattering particles (A) can be used individually or as a mixture of two or more types.
  • the used according to invention particles (B) have an average particle size V 5 o in the range of 10 to 150 microns, preferably 15 to 70 microns, and more preferably 30 to 50 .mu.m, wherein the refractive index of the particles have a sodium D line (589 nm) and the refractive index n 0 measured at 20 ° C, which differs by 0 to 0.2 units from the refractive index no of the matrix carbon.
  • the particles (B) can also be obtained commercially. These particles can be produced from the same materials as the scattering particles (A), plastic particles also preferably being used.
  • the spherical particles (B) preferably comprise crosslinked polystyrene, polysilicon and / or crosslinked poly (meth) acrylates.
  • the particles (B) described above can be used individually or as a mixture of two or more types.
  • the weight ratio of the scattering particles (A) to the particles (B) is preferably in the range from 1:10 to 10: 1, in particular 1: 5 to 5: 1, particularly preferably 1: 3 to 3: 1 and very particularly preferably 1: 2 to 2: 1.
  • the difference between the mean particle size V 50 of the scattering particles (A) and the particles (B) is preferably at least 5 ⁇ m, in particular at least 10 ⁇ m, the particles (B) being larger than the scattering particles (A).
  • the particle size and the particle size distribution can be determined using a laser extinction method.
  • a Galay-CIS from LOT GmbH can be used for this, the measurement method for determining the particle size and the particle size distribution being contained in the user manual.
  • the average particle size of V 50 results from the median of the weight average, 50% by weight of the particles being less than or equal to and 50% by weight of these particles being greater than or equal to this value.
  • these particles are present in the plastic matrix in a uniformly distributed manner without any significant aggregation or aggregation of the particles occurring. Evenly distributed means that the concentration of particles within the plastic matrix is essentially constant.
  • the light-scattering layer comprises a plastic matrix which has polymethyl methacrylate (PMMA).
  • PMMA polymethyl methacrylate
  • the light-scattering polymethyl methacrylate layer preferably comprises at least 30% by weight, in particular at least 40% by weight and particularly preferably at least 50% by weight, based on the weight of the light-scattering layer, of polymethyl methacrylate.
  • Polymethyl methacrylates are generally obtained by radical polymerization of mixtures containing methyl methacrylate. In general, these mixtures contain at least 40% by weight, preferably at least 60% by weight and particularly preferably at least 80% by weight, based on the weight of the monomers, of methyl methacrylate.
  • these mixtures for the production of polymethyl methacrylates can contain further (meth) acrylates which can be copolymerized with methyl methacrylate.
  • the term (meth) acrylates encompasses methacrylates and acrylates and mixtures of the two.
  • Aryl (meth) acrylates such as benzyl (meth) acrylate or
  • Phenyl (meth) acrylate where the aryl radicals can in each case be unsubstituted or substituted up to four times;
  • Cycloalkyl (meth) acrylates such as 3-vinylcyclohexyl (meth) acrylate,
  • Glycol di (meth) acrylates such as 1,4-butanediol (meth) acrylate,
  • Trimethyloylpropantri (meth) acrylate Trimethyloylpropantri (meth) acrylate.
  • compositions to be polymerized can also have further unsaturated monomers which are copolymerizable with methyl methacrylate and the aforementioned (meth) acrylates.
  • 1-alkenes such as 1-hexene, 1-heptene
  • branched alkenes such as vinylcyclohexane, 3,3-dimethyl-1-propene, 3-methyl-1-diisobutylene, 4-methylpentene-1;
  • Styrene substituted styrenes with an alkyl substituent in the side chain, such as. B. ⁇ -methylstyrene and ⁇ -ethylstyrene, substituted styrenes with a
  • Alkyl substituents on the ring such as vinyltoluene and p-methylstyrene, halogenated
  • Styrenes such as monochlorostyrenes, dichlorostyrenes, tribromostyrenes and
  • Heterocyclic vinyl compounds such as 2-vinylpyridine, 3-vinylpyridine, 2-methyl
  • Maleic acid derivatives such as maleic anhydride, methyl maleic anhydride, maleimide, methyl maleimide; and dienes such as divinylbenzene.
  • these comonomers are used in an amount of 0 to 60% by weight, preferably 0 to 40% by weight and particularly preferably 0 to 20% by weight, based on the weight of the monomers, the compounds being used individually or can be used as a mixture.
  • the polymerization is generally started with known radical initiators.
  • the preferred initiators include the azo initiators well known in the art, such as AIBN and 1, 1-azobiscyclohexane carbonitrile, and peroxy compounds, such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, tert-butyl per-2-ethylhexanoate, ketone peroxide, methyl isobutyl ketone peroxide, and peroxide compounds , tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, 2,5-bis (2 ⁇ ethylhexanoyl-peroxy) -2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate, part-butyl peroxy-3,5,5-trimethylhexanoate, Dicumyl peroxide, 1, 1-
  • poly (meth) acrylates can be used here, which differ, for example, in molecular weight or in the monomer composition.
  • the matrix of the light-scattering layer can contain further polymers in order to modify the properties.
  • these include polyacrylonitriles, polystyrenes, polyethers, polyesters, polycarbonates and polyvinyl chlorides. These polymers can be used individually or as a mixture, copolymers also being derivable from the aforementioned polymers.
  • the weight average molecular weight M w of the homopolymers and / or copolymers to be used according to the invention as matrix polymers can vary within wide ranges, the molecular weight usually being matched to the intended use and the processing mode of the molding composition. In general, however, it is in the range between 20,000 and 1,000,000 g / mol, preferably 50,000 to 500,000 g / mol and particularly preferably 80,000 to 300,000 g / mol, without any intention that this should impose a restriction.
  • the matrix of the light-scattering polymethyl methacrylate layer has at least 70, preferably at least 80 and particularly preferably at least 90% by weight, based on the weight of the matrix of the light-scattering layer, of polymethyl methacrylate.
  • the poly (meth) acrylates of the matrix of the light-scattering layer have a refractive index measured at the Na-D line (589 nm) and at 20 ° C. in the range from 1.46 to 1.54.
  • the molding compositions for producing the light-scattering layer can contain customary additives of all kinds. These include, among other things, antistatic agents, antioxidants, mold release agents, flame retardants, lubricants, dyes, flow improvers, fillers, light stabilizers, UV absorbers and organic phosphorus compounds such as phosphites or phosphonates, pigments, weathering protection agents and plasticizers.
  • additives include, among other things, antistatic agents, antioxidants, mold release agents, flame retardants, lubricants, dyes, flow improvers, fillers, light stabilizers, UV absorbers and organic phosphorus compounds such as phosphites or phosphonates, pigments, weathering protection agents and plasticizers.
  • additives include, among other things, antistatic agents, antioxidants, mold release agents, flame retardants, lubricants, dyes, flow improvers, fillers, light stabilizers, UV absorbers and organic phosphorus compounds such as phosphites or phosphonates, pigments, weathering
  • the molding composition can optionally be given a mechanically more stable finish by means of an impact modifier.
  • the impact modifier for polymethacrylate plastics is well known, so the manufacture and construction of impact modified polymethacrylate molding compositions are described, inter alia, in EP-A 0 113 924, EP-A 0 522 351, EP-A 0 465 049 and EP-A 0 683 028.
  • Preferred impact-resistant molding compositions which can be used to produce the matrix have 50-99% by weight, in particular 70-98% by weight, of polymethyl methacrylates, based on the weight of the molding composition without scattering particles (A) and particles (B). These polymethyl methacrylates have been previously described.
  • the polymethyl methacrylates used to produce impact-modified molding compositions are obtained by radical polymerization of mixtures which contain 80 to 100% by weight, preferably 90 to 98% by weight, methyl methacrylate and optionally 0 to 20% by weight. %, preferably 2-10% by weight of further free-radically polymerizable comonomers, which were also listed above.
  • Particularly preferred comonomers include C 1 -C 4 -alkyl (meth) acrylates, in particular methyl acrylate, ethyl acrylate or butyl methacrylate.
  • the average molecular weight M w of the polymethyl methacrylates which can be used to produce the impact-modified matrix is preferably in the range from 90,000 g / mol to 200,000 g / mol, in particular 100,000 g / mol to 150,000 g / mol.
  • Preferred impact-resistant molding compositions which can be used to prepare the matrix contain 0.5 to 55, preferably 1 to 45, particularly preferably 2 to 40, in particular 3 to 35% by weight of an impact modifier, based on the weight of the molding composition without scattering particles ( A) and particles (B), which is an elastomer phase made of crosslinked polymer particles.
  • the impact modifier can be obtained in a manner known per se by bead polymerization or by emulsion polymerization.
  • Preferred impact modifiers are crosslinked particles with an average particle size in the range from 50 to 1000 nm, preferably 60 to 500 nm and particularly preferably 80 to 120 nm.
  • Such particles can be obtained, for example, by the radical polymerization of mixtures which generally have at least 40% by weight, preferably 50 to 70% by weight, of methyl methacrylate,
  • a crosslinking monomer e.g. B. a multifunctional (meth) acrylate, such as. B. allyl methacrylate and
  • the preferred comonomers include, among others, -C-alkyl (meth) acrylates, such as ethyl acrylate or butyl methacrylate, preferably methyl acrylate, or other vinyl-polymerizable monomers such as, for. B. styrene.
  • the mixtures for producing the abovementioned particles can preferably comprise 0 to 10, preferably 0.5 to 5% by weight of comonomers.
  • Particularly preferred impact modifiers are polymer particles which have a two, particularly preferably a three-layer core-shell structure.
  • core-shell polymers are described, inter alia, in EP-A 0 113 924, EP-A 0 522 351, EP-A 0 465 049 and EP-A 0 683 028.
  • Particularly preferred impact modifiers based on acrylate rubber have the following structure, among others:
  • Core polymer with a methyl methacrylate content of at least 90% by weight, based on the weight of the core.
  • Shell 1 polymer with a butyl acrylate content of at least 80% by weight, based on the weight of the first shell.
  • Shell 2 polymer with a methyl methacrylate content of at least 90% by weight, based on the weight of the second shell.
  • the core and the shells can each contain other monomers in addition to the monomers mentioned. These were set out above, with particularly preferred comonomers having a crosslinking effect.
  • a preferred acrylate rubber modifier can have the following structure:
  • Core copolymer of methyl methacrylate (95.7% by weight), ethyl acrylate (4% by weight) and allyl methacrylate (0.3% by weight)
  • S1 copolymer of butyl acrylate (81.2% by weight), styrene (17.5% by weight) and allyl methacrylate (1.3% by weight)
  • S2 copolymer of methyl methacrylate (96% by weight) and ethyl acrylate (4% by weight)
  • the ratio of core to shell (s) of the acrylate rubber modifiers can vary within wide ranges.
  • the weight ratio core to shell K / S is preferably in the range from 20:80 to 80:20, preferably from 30:70 to 70:30 to modifiers with one shell or the ratio of core to shell 1 to shell 2 K / S1 / S2 in the range from 10:80:10 to 40:20:40, particularly preferably from 20:60:20 to 30:40:30 for modifiers with two shells.
  • the particle size of the core-shell modifiers is usually in the range from 50 to 1000 nm, preferably 100 to 500 nm and particularly preferably from 150 to 450 nm, without any intention that this should impose a restriction.
  • Such impact modifiers are commercially available from Mitsubishi under the trade name METABLEN® IR 441.
  • impact-modified molding compounds can also be obtained.
  • Particularly preferred molding compositions for the production of the plastic matrix are commercially available from Röhm GmbH & Co. KG.
  • the thickness of the light-scattering polymethyl methacrylate layer is generally in the range from 0.05 to 5 mm, preferably in the range from 0.05 to 2 mm and particularly preferably in the range from 0.1 to 1 mm.
  • the concentration of the spherical scattering particles (A) CPA, the thickness of the light-scattering polymethyl methacrylate layer ds and the particle size of the spherical scattering particles (A) DPA SO are chosen such that the ratio of the product of the concentration of the spherical scattering particles (A) Cp A and Thickness of the light-scattering polymethyl methacrylate layer to the third power of the particle size of the spherical scattering particles (A) cpA * ds / D PA 3 in the range from 0.001 to 0.015% by weight * mm / ⁇ m 3 , preferably 0.0025 to 0.009% by weight * mm / ⁇ m 3 .
  • the concentration of the spherical particles (B) CPB, the thickness of the light-scattering polymethyl methacrylate layer ds and the particle size of the spherical particles (B) DPB is chosen so that the ratio of the product of the concentration of the spherical scattering particles (B) CPB and the thickness of the light-scattering polymethyl methacrylate layer for the third power of the particle size of the spherical scattering particles (B) cps * s / DpB 3 in the range from 0.000005 to 0.002% by weight * mm / ⁇ m 3 , preferably 0.00004 to 0.0015% by weight % * mm / ⁇ m 3 % by weight * mm / ⁇ m 3 .
  • the ratio of the square of the average surface roughness of the polymethyl methacrylate layer Rz to the third power of the particle size of the spherical particles (B) R Z 2 / D PB 3 can preferably be in the range from 0.0002 ⁇ m "1 to 0.1300 ⁇ m " 1 , in particular 0.0009 ⁇ m “1 to 0.0900 ⁇ m " 1 and preferably 0.00025 ⁇ m “1 to 0.0600 ⁇ m “ 1 and particularly preferably 0.0025 ⁇ m "1 to 0.0600 ⁇ m " 1 .
  • the ratio of the concentration of the spherical scattering particles (A) CPA to the thickness of the light-scattering polymethyl methacrylate layer ds cp A / ds is greater than or equal to 2.5% by weight / mm, in particular greater than or equal to 4 wt .-% / mm.
  • the ratio of the concentration of the spherical particles (B) CPB to the thickness of the light-scattering polymethyl methacrylate layer ds Cp B / ds is greater than or equal to 2.5% by weight / mm, in particular greater than or equal to 4 wt .-% / mm.
  • the ratio of the thickness of the light-scattering polymethyl methacrylate layer ds to the particle size of the spherical scattering particles D PA ds / D PA is preferably in the range from 1 to 500, in particular 1 to 250, preferably 2.5 to 250 and particularly preferably 2.5 to 150, without any limitation.
  • the light-scattering polymethyl methacrylate layer preferably has a gloss R 85 ° of less than or equal to 60, in particular less than or equal to 40 and particularly preferably less than 30.
  • the rear projection screens of the present invention show a particularly low sensitivity to scratching.
  • scratches which are generated on the screen with a force of at most 0.4 N, in particular of at most 0.7 N and particularly preferably of at most 1.0 N are not visually recognizable, without this being intended to impose a restriction.
  • This scratch resistance can be determined in accordance with DIN 53799 and DIN EN 438 by a visual assessment of a damaged surface, the damage being caused by a diamond which acts on the surface with different forces.
  • the average surface roughness Rz of the plate is preferably in the range from 5 ⁇ m to 50 ⁇ m, in particular 5 to 25 ⁇ m, preferably 6 to 35 ⁇ m, in particular 15 ⁇ m to 50 ⁇ m, particularly preferably 6 ⁇ m to 30 ⁇ m ,
  • the average surface roughness R z can be determined in accordance with DIN 4768 with a Talysurf 50 measuring device from Taylor Hobson, where Rz is the average roughness depth which results from the mean values of the individual roughness depths of five successive individual measuring sections in the roughness profile.
  • the surface roughness Rz of the plate generally results from the choice of the particles (B).
  • this value can be influenced by varying various parameters, which depend on the type of manufacture.
  • the temperature of the melt depends on the exact composition of the molding compound.
  • the temperature of the melt is generally in the range from 150 to 300 ° C., preferably in the range from 200 to 290 ° C. These temperatures refer to the temperatures of the melt at the nozzle outlet.
  • the surface roughness can be influenced via the gap between the rollers used to smooth the plates.
  • a calender comprises, for example, 3 rolls in an L arrangement, the molding compound being guided from the nozzle onto the nip between roll 1 and roll 2 and looping around the roll 2 by 60-180 °, the gap between roll 2 and roll 3 smoothes the surfaces. If the gap between roller 2 and roller 3 is set to plate thickness, the scattering particles on the plate surface are pressed into the matrix, which makes the surface appear smoother.
  • this gap is set somewhat larger than the plate thickness of the plate to be produced in order to achieve a rougher surface, this value often being in the range from 0.1 to 2 mm above plate thickness, preferably 0.1 to 1.5 mm above plate thickness, without that this should result in a restriction.
  • the surface roughness is influenced by the particle size and the plate thickness, the exemplary embodiments setting out the dependencies.
  • the light-scattering layer can be produced by known processes, thermoplastic molding processes being preferred. After the addition of the particles, light-scattering layers can be produced from the molding compositions described above by conventional thermoplastic molding processes.
  • a twin-screw extruder is used for the extrusion or for the production of molding compound granules containing scattering pearls.
  • the plastic particles are preferably transferred to the melt in the extruder.
  • the rear projection screens can be produced using a two-stage process, in which a sidefeeder compounding according to the invention is connected to a twin-screw extruder and intermediate granulation is followed by extrusion of the film or plate on a single-screw extruder.
  • the granules obtained via the twin-screw extruder can contain particularly high proportions of scattering pearls, so that projection screens with different scattering pearls content can be produced in a simple manner by mixing with molding compositions without scattering pearls.
  • a one-step process can also be carried out, in which the spherical plastic particles are compounded into the melt as described on a twin-screw extruder, which may be followed by a pressure-increasing unit (e.g. melt pump), to which the extrusion nozzle is directly connected, with which a flat product is formed.
  • a pressure-increasing unit e.g. melt pump
  • rear projection screens with a particularly low yellow index can be obtained by the measures described above.
  • the screens can also be produced by injection molding, but the process parameters or the mold must be selected such that a surface roughness is achieved in the area according to the invention.
  • the matrix is preferably compounded with the scattering particles by means of a twin-screw extruder; a single-screw extruder can also be used in the actual plate extrusion, without any intention that this should impose a restriction.
  • the light-scattering polymethyl methacrylate layer can be used as a screen.
  • the thinner layers can be used as a rollable film. Particularly preferred films are made impact resistant by the methods set out above.
  • a thin light-scattering polymethyl methacrylate layer can be applied to a plastic plate in order to increase its mechanical stability.
  • This plastic plate which serves as a carrier layer, preferably has an intensity half-value angle of less than 6.5 °, in particular less than or equal to 6 °, preferably less than or equal to 5 ° and particularly preferably less than or equal to 3 °.
  • the carrier layer comprises no or only a small amount of spherical particles which have a scattering effect.
  • This plastic sheet preferably has poly (meth) acrylates.
  • the surface of the carrier layer preferably has a gloss of less than or equal to 70, preferably less than or equal to 60, in particular less than or equal to 40, particularly preferably less than or equal to 30 and very particularly preferably less than or equal to 15 at an angle of 60 °.
  • the carrier layer has an average surface roughness Rz in the range from preferably 2 ⁇ m to 45 ⁇ m, in particular 3 to 40 ⁇ m, preferably 5 to 35 ⁇ m. In this way, reflections of the image projected on the screen into the room can be avoided without the image quality being impaired.
  • the screen has a transmission greater than or equal to 25%, in particular greater than or equal to 40% and particularly preferably greater than or equal to 55%, these values can be achieved in particular from screens without contrast-enhancing dyes.
  • the molding composition can be colored. This measure can surprisingly improve the contrast.
  • Dyes and / or soot known per se are particularly suitable for coloring.
  • Particularly preferred dyes are commercially available. These include, among others, ⁇ Sandoplast Rot G and ⁇ Sandoplast Gelb 2G each from Clariant and ⁇ Macrolex Grün 5B and ⁇ Macrolex Violett 3R each from Bayer.
  • the concentration of these dyes depends on the desired color impression and the thickness of the plate. Without being restricted thereby, this concentration per dye is generally in the range from 0 to 0.8% by weight, preferably 0.000001 to 0.4% by weight, based on the total weight of the colored molding composition without scattering particles (A) and particles (B).
  • the sum of the dye concentrations is preferably in the range from 0 to 1% by weight, preferably 0.0001 to 0.6% by weight, based on the total weight of the colored molding composition without scattering particles (A) and particles (B).
  • the loss of transmission can at least partially be compensated for by stronger projectors.
  • the screen preferably shows a yellowness index of less than or equal to 12, in particular less than or equal to 10, without this being intended to impose a restriction.
  • a special embodiment of the screen of the present invention has an intensity half-value angle greater than or equal to 15 °, in particular greater than or equal to 25 °.
  • the screen has a scattering power greater than or equal to 0.15, in particular greater than or equal to 0.35, without this being intended to impose a restriction.
  • the surface of the polymethyl methacrylate plates according to the invention have a matt appearance when reflected on the lens.
  • the characterization can be carried out by measuring the gloss with a reflectometer according to DIN 67530.
  • the gloss of the plates is preferably at an angle of 85 ° below 60, particularly preferably below 40 and very particularly preferably below 30.
  • the size and shape of the rear projection screen of the present invention is not limited. In general, however, the screen has a rectangular, tabular shape, since images are usually displayed in this format.
  • Such a rear projection screen preferably has a length in the range from 25 mm to 10000 mm, preferably from 50 to 3000 mm and particularly preferably from 200 to 2000 mm.
  • the width of this particular embodiment is generally in the range from 25 to 10000 mm, preferably from 50 to 3000 mm and particularly preferably from 200 to 2000 mm. In order to provide a particularly large projection area, several of these screens can be combined.
  • the screen has a particularly high weather resistance in accordance with DIN EN ISO 4892, Part 2 -Artificial weathering or irradiation in devices, filtered xenon arc radiation.
  • the rear projection screens according to the invention can be used for other lighting applications, for example as diffusing screens in LCD monitors.
  • the average roughness Rz was determined in accordance with DIN 4768 using a Talysurf 50 measuring device from Taylor Hobson.
  • the transmission XD 6 5/2 ° was determined in accordance with DIN 5036 with a Lambda 19 measuring device from Perkin Elmer.
  • the yellowness index ⁇ D65 / - ⁇ o ° was determined in accordance with DIN 6167 with a Lambda 19 measuring device from Perkin Elmer.
  • the gloss R85 ° was measured at 85 ° according to DIN 67530 with a Dr. Long laboratory reflectometer from Dr. For a long time.
  • the scattering power and the intensity half-value angle were determined in accordance with DIN 5036 using an LMT goniometer measuring station GO-T-1500 from LMT.
  • the various rear projection screens were also assessed visually according to the criteria set out in Table 1.
  • a projector of the brand Epson EMP-713 was used for this.
  • the distance between the projector and the projection screen was approx. 85 cm with an image diagonal of approx. 50 cm.
  • Projection system dichroic mirror and lens system, picture elements: 2359296 pixels (1024x768) * 3, brightness: 1200 ANSI lumens, contrast: 400: 1, image illumination: 85%, color rendering: 24 bit with 16.7 million colors, H: 15-92 kHz, V: 50-85 Hz, lamp: 150 watt UHE, video resolution: 750 TV lines
  • An aluminum hydroxide Pickering stabilizer was used to produce spherical plastic particles, which was prepared by precipitation from aluminum sulfate and soda solution immediately before the actual polymerization started.
  • 16 g of Al 2 (SO) 3 , 0.032 g of complexing agent (Trilon A) and 0.16 g of emulsifier (emulsifier K 30 available from Bayer AG; sodium salt of a C 5 -paraffin sulfonate) in 0.81 distilled water were first solved.
  • a 1 N sodium carbonate solution was then added to the aluminum sulfate dissolved in water with stirring at a temperature of about 40 ° C., the pH then being in the range from 5 to 5.5. This procedure resulted in a colloidal distribution of the stabilizer in the water.
  • the aqueous phase was placed in a beaker transferred. 110 g of methyl methacrylate, 80 g of benzyl methacrylate and 10 g of allyl methacrylate, 4 g of dilauryl peroxide and 0.4 g of tert-butyl per-2-ethylhexanoate were added. This mixture was dispersed for 15 minutes at 7000 rpm using a disperser (Ultra-Turrax S50N-G45MF, from Janke and Kunkel, Staufen).
  • the reaction mixture was poured into the reactor, which was preheated to the appropriate reaction temperature of 80 ° C., and polymerized at about 80 ° C. (polymerization temperature) for 45 minutes (polymerization time) with stirring (600 rpm). This was followed by a post-reaction phase of 1 hour at an internal temperature of approx. 85 ° C. After cooling to 45 ° C., the stabilizer was converted into water-soluble aluminum sulfate by adding 50% sulfuric acid. To work up the beads, the suspension obtained was filtered through a commercially available filter cloth and dried in a heating cabinet at 50 ° C. for 24 hours.
  • the size distribution was examined by laser extinction methods.
  • the particles had an average size V 50 of 18.6 ⁇ m.
  • the beads had a spherical shape, with no fibers being found. Coagulation did not occur.
  • the particles obtained in this way are referred to below as plastic particles B1.
  • An aluminum hydroxide Pickering stabilizer was used to produce spherical plastic particles, which was prepared by precipitation from aluminum sulfate and sodium carbonate solution (1N sodium carbonate solution) immediately before the actual polymerization started. For this purpose, 38 ions were initially used. Water, 400 g of aluminum sulfate and 8 g of complexing agent (Trilon A) with stirring (330 rpm) using an impeller stirrer in a mixture with N 2 rinsed 100 L V4A boiler with breakwater, Ni-Cr-Ni thermocouple and circulation heating.
  • Trilon A complexing agent
  • a monomer mixture consisting of 6900 g of methyl methacrylate, 3000 g of styrene, 100 g of glycol dimethacrylate, 200 g of dilauroyl peroxide, 20 g of tert-butyl per-2-ethylhexanoate and 50 g of 2-ethylhexylthioglycolate is then also added at room temperature.
  • the heating phase takes place up to a temperature of 80 ° C., the reactor being sealed pressure-tight at an internal boiler temperature of 40 ° C. and the N 2 introduction being shut off. Over the next 115 minutes the internal temperature rises to approx. 87 ° C and the pressure increases from 0.70 to 0.92 bar. After the maximum temperature, the reaction mixture was heated to about 87-88 ° C. and stirred at this temperature for about an hour, the stirring speed being reduced to 200 rpm. After the reaction mixture had been cooled, the kettle was let down at a temperature of 46 ° C. and then 400 ml of 50% strength sulfuric acid were added, as a result of which the aluminum hydroxide is converted into the soluble aluminum sulfate and the suspension polymer thereby precipitates out.
  • the suspension obtained was filtered through a stoneware filter with a filter cloth, washed neutral and dried at 50 ° C. in an oven for about 20 hours.
  • the size distribution was examined by laser extinction methods.
  • the particles had an average size V 50 of 40.5 ⁇ m.
  • the beads had a spherical shape, with no fibers being found. Coagulation did not occur.
  • the particles obtained in this way are referred to below as plastic particles B2.
  • the loads used are set out in Table 4.
  • the visual assessment was carried out on a black background (reflection test).
  • the tests (roughness, gloss) on the test extrudates were carried out on the top.
  • the rear projection screens obtained were examined in accordance with the measurement methods described above, the measurement results obtained being shown in Table 6.
  • the mechanical properties of the rear projection screens were also examined.
  • the tensile strength, the elongation at break and the modulus of elasticity were determined in accordance with ISO 527-2 and the reflection in accordance with DIN 5036.
  • the rear projection screen according to the invention can also be used for the 3D projection of images or films.
  • two projections are superimposed as image sources, which in principle transmit the same image content, but which is at a certain distance, e.g. B. were added at eye relief.
  • a commonly used principle is e.g. B. the polarization process.
  • the viewer views the image through glasses which are each equipped with appropriate polarization filters for the right and left eyes.
  • the human brain processes the two different image impressions into a three-dimensional image perception.
  • the rear projection screens according to the invention can preferably be made from extruded polymethyl methacrylate plastic in the form of a plate or film comprising at least one light-scattering layer from extruded polymethyl methacrylate plastic, the path difference due to the optical birefringence overall being at most 25 nm, preferably at most 15, particularly preferably at most 5 nm.
  • extrusion process always causes a certain orientation of the molecular chains in the extrusion direction. This alignment leads to birefringence properties which partially depolarize the polarized light of the two projections, which is of course undesirable.
  • the extruded polymethyl methacrylate plastic for rear projection screens which are intended for 3D projection is therefore particularly preferably subjected to a thermal aftertreatment after the extrusion. During thermal aftertreatment, shrinkage occurs, which largely negates the alignment of the polymer molecules. The result is that the birefringence property originally present in the material is greatly reduced.
  • the thermal aftertreatment of extruded polymethyl methacrylate plastic in the form of foils or plates which are provided for rear projection screens for 3D projection can, for. B. in the range of 110 to 190, preferably 120 to 160 ° C for 5 minutes to 24 hours, preferably 10 minutes to 2 hours, depending on the material composition and material thickness.
  • the thermally induced shrinking process can be carried out with material lying or preferably hanging.
  • the path difference can e.g. B. be measured using a polarization microscope in combination with an Ehringhaus tilt compensator.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Optical Elements Other Than Lenses (AREA)
  • Overhead Projectors And Projection Screens (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

L'invention concerne un écran de rétroprojection comprenant au moins une couche de polyméthylméthacrylate diffusant la lumière, qui présente une matrice de polyméthylméthacrylate ainsi que des particules diffusantes sphériques (A) et des particules sphériques (B) de grandeurs moyennes V50 différentes. Les particules diffusantes sphériques (A) présentent une grandeur moyenne V50 située dans une plage allant de 0,1 à 40 µm et une différence d'indice de réfraction par rapport à la matrice de polyméthylméthacrylate située dans une plage allant de 0,02 à 0,2. Les particules sphériques (B) présentent une grandeur moyenne V50 située dans une plage allant de 10 à 150 µm et une différence d'indice de réfraction par rapport à la matrice de polyméthylméthacrylate située dans une plage allant de 0 à 0,2. La concentration totale des particules diffusantes sphériques (A) et des particules (B) se situe dans une plage allant de 1 à 60 % en poids par rapport au poids de la couche de polyméthylméthacrylate diffusant la lumière. La concentration de particules diffusantes sphériques (A) cPA, l'épaisseur dS de la couche de polyméthylméthacrylate diffusant la lumière ainsi que la grandeur DPA des particules diffusantes sphériques (A) sont sélectionnées de sorte que le rapport cPA*ds/DPA3 se situe dans une plage allant de 0,001 à 0,015 % en poids*mm/µm3. La concentration de particules sphériques (B) cPB, l'épaisseur dS de la couche de polyméthylméthacrylate diffusant la lumière et la grandeur DPB des particules sphériques (B) sont sélectionnées de sorte que le rapport cPB *dS/DPB3 se situe dans une plage allant de 0,000005 à 0,002 % en poids*mm/µm3 et le rapport du carré de la rugosité de surface moyenne RZ de la couche de polyméthylméthacrylate sur le cube de la grandeur des particules sphériques (B) RZ2/DPB3 se situe dans une plage allant de 0,0002 µm-1 à 0,1300 µm-1.
EP04719963A 2003-08-04 2004-03-12 Ecran de retroprojection resistant aux rayures et son procede de production Ceased EP1652001A1 (fr)

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DE10336129A DE10336129A1 (de) 2003-08-04 2003-08-04 Kratzunempfindlicher Rückprojektionsschirm und Verfahren zu dessen Herstellung
PCT/EP2004/002599 WO2005022253A1 (fr) 2003-08-04 2004-03-12 Ecran de retroprojection resistant aux rayures et son procede de production

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Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10336131A1 (de) * 2003-08-04 2005-02-24 Röhm GmbH & Co. KG Stabiler Rückprojektionsschirm sowie Verfahren zu dessen Herstellung
JP2005258155A (ja) * 2004-03-12 2005-09-22 Dainippon Printing Co Ltd 透過型スクリーン用光拡散部材
JP2005352275A (ja) * 2004-06-11 2005-12-22 Dainippon Printing Co Ltd 透過型スクリーン用表面保護部材
JP2005352238A (ja) * 2004-06-11 2005-12-22 Dainippon Printing Co Ltd 光拡散部材
US7210792B2 (en) * 2004-11-29 2007-05-01 Arisawa Manufacturing Co., Ltd Projection system and method
DE102005055793A1 (de) 2005-11-21 2007-05-24 Röhm Gmbh Transparente TPU (thermoplastische Polyurethane)/ PMMA (Polymethyl(meth)acrylat) Abmischungen mit verbesserter Kältesschlagzähigkeit
DE102006029613A1 (de) 2006-06-26 2007-12-27 Röhm Gmbh Transparenter Kunststoff-Verbund
CN102093689A (zh) * 2010-12-27 2011-06-15 金发科技股份有限公司 一种光散射功能母粒及其制备方法与应用
DK2828345T3 (da) 2012-03-22 2017-01-02 3M Innovative Properties Co Polymethylmethacrylatbaseret hårdbelægningssammensætning og overtrukken artikel
JP5949356B2 (ja) * 2012-09-07 2016-07-06 大日本印刷株式会社 反射スクリーン、立体映像表示システム
US9348066B2 (en) * 2013-03-08 2016-05-24 Samsung Electronics Co., Ltd. Film for improving color display and method of manufacturing the same
KR102067161B1 (ko) * 2013-03-08 2020-01-16 삼성전자주식회사 색 개선 필름 및 그 제조방법
EP2775327B1 (fr) * 2013-03-08 2020-02-26 Samsung Electronics Co., Ltd. Film pour améliorer la détection de couleur et son procédé de fabrication et appareil d'affichage comprenant un film améliorant la détection de couleur
KR102067162B1 (ko) * 2013-03-08 2020-01-16 삼성전자주식회사 색 개선 필름 및 그 제조방법
KR102067160B1 (ko) * 2013-05-31 2020-01-16 삼성전자주식회사 색 개선 필름 및 그 제조방법
KR102067163B1 (ko) * 2013-06-03 2020-01-16 삼성전자주식회사 색 개선 필름 및 그 제조방법
JP6563383B2 (ja) * 2014-04-14 2019-08-21 国立大学法人東京工業大学 透明スクリーン用フィルムおよびその製造方法ならびにそれを備えた透明スクリーン
US9176370B1 (en) * 2014-06-12 2015-11-03 Google Inc. High contrast rear projection screen
US9013790B1 (en) * 2014-06-12 2015-04-21 Google Inc. High contrast rear projection screen for use with a diverging illumination source
US9250508B1 (en) 2014-11-17 2016-02-02 Google Inc. Rear projection screen with pin-hole concentrator array
US9256115B1 (en) 2014-12-29 2016-02-09 Google Inc. Dual sided lens array using clear beads
KR102488716B1 (ko) * 2015-01-05 2023-01-13 도요보 가부시키가이샤 직하형 면광원용 백색 반사 필름 및 그것을 사용한 직하형 면광원
US9519206B1 (en) 2015-06-25 2016-12-13 X Development Llc High contrast projection screen with stray light rejection
US9772550B2 (en) 2015-08-04 2017-09-26 X Development Llc Apparatus, system and method for mitigating contrast artifacts at an overlap region of a projected image
DE202015106994U1 (de) * 2015-12-22 2017-03-23 Rehau Ag + Co Streuscheibe
WO2019111825A1 (fr) * 2017-12-05 2019-06-13 積水化学工業株式会社 Système d'affichage d'image et procédé d'affichage d'image
HUE050397T2 (hu) * 2018-02-05 2020-12-28 Roehm America Llc Javított szórási hatékonyságú és javított mechanikai tulajdonságú fénytszóró polimer készítmény
CN109061992A (zh) * 2018-08-01 2018-12-21 张家港康得新光电材料有限公司 投影膜与包括其的投影系统
CN111435183A (zh) * 2019-05-24 2020-07-21 宁波激智科技股份有限公司 一种夹层调光片及其制备方法
CN116106999B (zh) * 2023-04-13 2023-08-22 Tcl华星光电技术有限公司 光扩散膜及偏光片
US12032244B1 (en) 2023-04-13 2024-07-09 Tcl China Star Optoelectronics Technology Co., Ltd. Light diffusion film, polarizer, and liquid crystal display device

Family Cites Families (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3300526A1 (de) 1983-01-10 1984-07-12 Röhm GmbH, 6100 Darmstadt Schlagzaehmodifizierungsmittel
JPS6377940A (ja) 1986-09-19 1988-04-08 Toshiba Silicone Co Ltd 真球状ポリメチルシルセスキオキサン粉末およびその製造方法
CA1337104C (fr) 1986-11-18 1995-09-26 William James Work Polymeres thermoplastiques dispersant la lumiere
DE3878556T2 (de) 1988-05-18 1993-08-05 Rohm & Haas Thermoplastische und waermehaertbare zusammensetzungen.
US5063259A (en) 1990-07-03 1991-11-05 Rohm And Haas Company Clear, impact-resistant plastics
JP2981268B2 (ja) 1990-09-27 1999-11-22 株式会社クラレ レンチキュラーレンズシート
DE4121652A1 (de) 1991-06-29 1993-01-07 Roehm Gmbh Schlagzaeh-modifizierungsmittel
JPH0551480A (ja) 1991-08-26 1993-03-02 Matsushita Electric Works Ltd 高透過高拡散プラスチツク
US5307205A (en) 1992-03-20 1994-04-26 Rohm And Haas Company Bilayer rear projection screens
DE4327464A1 (de) 1993-08-16 1995-02-23 Roehm Gmbh Verfahren zur Herstellung monodisperser Poly(meth)acrylat-Teilchen
JPH07234304A (ja) 1994-02-23 1995-09-05 Soken Kagaku Kk 光拡散板
DE4417559A1 (de) 1994-05-19 1995-11-23 Roehm Gmbh Verfahren zum Entwässern einer wasserhaltigen Kunststoffschmelze in einem Doppelschneckenextruder
JP3575098B2 (ja) 1995-01-30 2004-10-06 住友化学工業株式会社 成形品の製造方法
US6144491A (en) * 1996-02-29 2000-11-07 Dai Nippon Printing Co., Ltd. Reflection-type projection screen
EP0882249A1 (fr) * 1996-11-07 1998-12-09 Jenoptik LDT GmbH Dispositif comprenant un laser pour la reproduction d'images
US6519087B2 (en) * 1997-04-10 2003-02-11 3M Innovative Properties Company Rear projection screen incorporating diffuser
JP4171933B2 (ja) * 1997-09-12 2008-10-29 ソニー株式会社 平面型レンズの製造方法
JPH11179856A (ja) 1997-12-19 1999-07-06 Sumitomo Chem Co Ltd 艶消板
JP2000180973A (ja) * 1998-12-18 2000-06-30 Mitsubishi Rayon Co Ltd 透過型スクリーン
EP1152286A4 (fr) * 1998-12-18 2002-05-15 Mitsubishi Rayon Co Ecran de transmission
JP3970449B2 (ja) 1998-12-21 2007-09-05 モメンティブ・パフォーマンス・マテリアルズ・ジャパン合同会社 球状ポリメチルシルセスキオキサン微粒子の製造方法
JP4190649B2 (ja) 1999-04-16 2008-12-03 旭化成ケミカルズ株式会社 耐衝撃性光拡散樹脂板
GB9910941D0 (en) * 1999-05-11 1999-07-14 Microsharp Corp Limited High contrast screen material
US6204971B1 (en) * 1999-05-14 2001-03-20 3M Innovative Properties Company Glass microspheres for use in films and projection screen displays and methods
JP2001192452A (ja) 2000-01-13 2001-07-17 Ge Toshiba Silicones Co Ltd 球状シリコーン微粒子およびその製造方法
US6567215B2 (en) * 2001-09-04 2003-05-20 3M Innovative Properties Company Beaded rear projection screen with tunable gain
DE10222250A1 (de) * 2002-05-16 2003-11-27 Roehm Gmbh Verbesserte Lichtleitkörper sowie Verfahren zu dessen Herstellung
DE10251778A1 (de) * 2002-11-05 2004-05-19 Röhm GmbH & Co. KG Rückprojektionsschirm sowie Verfahren zu dessen Herstellung
DE10336130A1 (de) 2003-08-04 2005-02-24 Röhm GmbH & Co. KG Streuscheibe für LCD-Anwendungen, Verfahren zu deren Herstellung und Verwendung

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2005022253A1 *

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MXPA06001066A (es) 2006-04-11
EP2339398A1 (fr) 2011-06-29
RU2343521C2 (ru) 2009-01-10
US20060209403A1 (en) 2006-09-21
DE10336129A1 (de) 2005-02-24
KR20060120575A (ko) 2006-11-27
US7339732B2 (en) 2008-03-04
RU2343521C9 (ru) 2010-01-20
CA2533510A1 (fr) 2005-03-10
AU2004269461A1 (en) 2005-03-10
TW200509683A (en) 2005-03-01
RU2006106613A (ru) 2007-09-20
WO2005022253A1 (fr) 2005-03-10
JP2007501423A (ja) 2007-01-25
CN1823300A (zh) 2006-08-23
AU2004269461B2 (en) 2009-09-10

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