WO2013167542A1

WO2013167542A1 - Light guide plate

Info

Publication number: WO2013167542A1
Application number: PCT/EP2013/059408
Authority: WO
Inventors: Norbert Pingel
Original assignee: Bayer Materialscience Gmbh
Priority date: 2012-05-08
Filing date: 2013-05-06
Publication date: 2013-11-14

Abstract

The invention relates to a light guide plate (2, 2.1), in particular a light guide web plate (2, 2.1), comprising a first layer (4, 4.1) and at least one second layer (6, 6.1), wherein the first layer (4, 4.1) is connected to the second layer (6, 6.1) by means of a plurality of web-shaped connecting elements (8), wherein at least one web-shaped connecting element (8) is modified in such a way that the web-shaped connecting element (8) has at least one predeterminable transmittance property and the web-shaped connecting elements (8) are connected to the first layer (4, 4.1) and the second layer (6, 6.1) in such a way that the first layer (4, 4.1) can be displaced relative to the second layer (6, 6.1) in at least one longitudinal direction, wherein the position of the web-shaped connecting elements (8) with respect to the first layer (4, 4.1) and the second layer (6, 6.1) can be uniformly changed by the relative displacement, wherein the light guide plate can be produced by means of extrusion.

Description

Lichtführungspiatte

The invention relates to a light guide plate, in particular a Lichtführungsstegplatte comprising a first layer and at least one second layer, wherein the first layer is connected via a plurality of web-shaped connecting elements with the second layer. In addition, the invention relates to a glazing system comprising at least one of these light guide plates and a use of the light guide plate.

Transparent and / or translucent panels are used in many ways today. In particular, such plates are used as discs in various glazing systems.

Exemplary plates for glazing systems are so-called multiwall sheets. Web plates have a first layer, such as a top flange, and at least a second layer, such as a bottom flange. The two layers are interconnected by a plurality of web-shaped connecting elements. Here, the web-shaped connecting elements are perpendicular to the first layer and perpendicular to the second layer, so that result in the web plate rectangular cavities.

For better stability, these webs at their ends, ie at the connecting regions with the respective layer, each have a thickening, that is, more material. In particular, the web-shaped connecting elements widen at both ends. For example, EP 1 792 703 A2 discloses conventional web plates. It is understood that a plurality of layers or straps may be provided in a web plate. Corresponding plates are also called web multiple plates. Glazings, such as a previously described web plate, provide protection against various environmental influences. In conventional panels, for example, a certain protective effect against light radiation, in particular with respect to solar radiation, can be achieved by establishing a specific choice for the base material, the geometry, the coloring, etc. The produced plate then has certain transmission properties with respect to the incident radiation, which are invariable. In order to obtain a variable radiation and in particular sun protection, it is known from the prior art, for example, to arrange additional shading systems, such as sun awnings, sun blinds, sun blades and the like. Preferably, the additional shading systems are mounted above the glazing. However, the attachment of additional shading systems is expensive and expensive.

An alternative solution known from the prior art is a special paint for glazing systems. So the panels can be provided in the summer with a certain coat of paint, which protects against excessive sunlight. For example, if increased sunshine is desired for the remainder of the year, the paint can be washed off again, for example. The disadvantage here is / one that only a small variability can be achieved. On the other hand, a high expenditure and corresponding costs are associated with painting and washing the paint. Other already known glazings are so-called thermo- and / or photochromic glazings. Such glazings are characterized in that they have switching points, such as certain tempera ture values or the like, in which the sun protection properties of the plate change. In addition to the high cost of such glazing, it is disadvantageous that a user can not change the switching points and therefore no user-specific switching is possible. In addition, web plates are due to the high extrusion rate in this case not as plates.

Also electrochromic glazing systems are known, which, however, can be realized only in small dimensions and also bring high costs.

It is therefore an object of the present invention to provide a light guide plate which has an integrated and improved, in particular variable, light-guiding function. The previously derived and indicated object is achieved according to a first aspect of the invention in a light guide plate according to claim 1. A light guide plate, in particular a light guide web plate, comprises a first layer. The light guide plate comprises at least one second layer, wherein the first layer is connected to the second layer via a plurality of web-shaped connecting elements. At least one web-shaped connecting element is modified such that the web-shaped connecting element at least one having predetermined transmission property. The web-shaped connecting elements are connected to the first layer and the second layer such that the first layer is displaceable relative to the second layer in at least one longitudinal direction, whereby the position of the web-shaped connecting elements with respect to the first layer and the second Layer is uniformly changeable.

In contrast to the prior art, according to the invention, a light guide plate with integrated and variable light guiding function, in particular with a variable sunscreen, provided by at least one connecting element (targeted) is modified and a relative movement between a first layer and a second layer is made possible. As a result of the relative movement, the position of all connecting elements is uniformly changed so that at least one transmission property of the light guide plate can be adjusted in a targeted manner. In particular, an application-specific adjustment of at least one transmission property of the light guide plate is possible in a cost-effective and simple manner. Additional measures for a variable light-guiding function, in particular light protection, can be dispensed with.

The light guide plate according to the invention comprises at least two layers, ie flat elements, which may be arranged opposite one another and in particular parallel to one another. A first layer may for example be a top flange of a web plate and the second layer a bottom flange of a web plate. The layers are spaced apart. Furthermore, the layers are connected to one another by means of a plurality of web-shaped connecting elements. Web-shaped connecting elements are flat elements which have two opposite broad surfaces. Between the web-shaped connecting elements and the two layers are

Formed cavities, which may preferably include a gas, for example air.

It has been recognized that by a specific modification of the connecting regions between a web-shaped connecting element and the two layers, a relative versatility of the first layer to the second layer can be achieved. A relative displacement is to be understood as a displacement in which either both layers are displaceable in opposite longitudinal directions, ie a parallel displacement of the two layers takes place, or at least one of the two layers is displaceable in a longitudinal direction, while the respective other layer is not displaceable. The longitudinal direction here is to be understood as meaning a direction parallel to the surfaces of the two layers. In particular, according to the invention, a reversible relative displacement can be provided. In other words, the first layer can be moved to the second layer from a starting position in at least one further position and also moved back again. Due to the relative displacement, at least one transmission property of the light guide plate can be (selectively) influenced and, in particular, changed.

It has been recognized that the Lichtfuhrungsplatte can be provided with specific and in particular adjustable transmission properties, when used as web-shaped connecting elements modified web-shaped connecting elements. Preferably, all binding elements can be modified. Due to the uniform change in the position of the web-shaped connecting elements, which is caused by the relative displacement, at least one transmission characteristic of the Lichtfuhrungsplatte (targeted) changed, in particular increased or reduced. Under a uniform change in the position of the web-shaped connecting elements is to be understood in particular that all web-shaped connecting elements are moved uniformly in the same longitudinal direction. Thus, by the relative displacement of the two layers to each other, the position of all web-shaped connecting elements, which may be arranged parallel to each other, changed in relation to the first and the second layer in parallel. In other words, equal angles between the web-shaped connecting elements and the first layer have substantially the same amount. The same applies to the angle between the web-shaped connecting elements and the second layer.

In a simple manner, a light guide plate with an integrated and variably adjustable light-guiding function, in particular sun protection, can be provided.

According to a first embodiment of the light guide plate according to the invention, the position of the web-shaped can be due to the relative displacement of the first layer to the second layer

Connecting elements with respect to the first layer and the second layer to be changeable such that a Strahlenauftrefffläche on a surface of a web-shaped connecting element is changeable. in particular, this can change at least one transmission property of the light guide plate. By changing the position of the web-shaped connecting elements with respect to the layers, in particular the impact surface on the web-shaped connecting elements of incident on the light guide plate light radiation can be changed. A changed impact surface can lead to a changed transmission characteristic of the light guide plate. For example, a (sun) radiation protection function targeted switched on or off. Also, a targeted reflection of sun rays can be adjusted. Transmission properties of a light guide plate are properties that affect the transmission or reflection of electromagnetic waves, in particular of optical waves that strike the plate. For example, the transmission and / or the reflection of light radiation can be changed, in particular increased or reduced, by tilting the web-shaped connecting elements.

In a simple manner, a light guide plate can be provided, which can have an integrated and adjustable light guiding function, such as shading functions.

A web-shaped connecting element can be shaped as desired, as long as a connection between two layers can be formed. According to a preferred embodiment of the light guide plate according to the invention, the web-shaped connecting element may have a central portion, a first end connected to the first layer and another end connected to the second layer. In order to achieve a good relative shiftability of the at least two layers to one another, at least one end, in particular both ends of the web-shaped connecting element, can have at least a higher flexibility than the middle section of the web-shaped connecting element. Greater flexibility can result in better flexibility in the end regions or in the joining of the web-shaped connecting element. When a force is applied to a layer in a longitudinal direction, the layer may be displaced relative to the further layer due to the more flexible bonding areas.

Higher flexibility in the connection areas can be achieved in various ways. For example, a more flexible material can be used in the connecting regions, ie the ends, than in the middle section of the web-shaped connecting element. Additionally or alternatively, a targeted weakening of the material can take place in the region of one end, in particular in the regions of the two ends of the web-shaped connecting element. According to a preferred disclosed embodiment of the light guide plate according to the invention, the web-shaped connecting element in the region of the first end may have a taper and / or the web-shaped connecting element in the region of the other end have a taper. In addition to the increased flexibility of a correspondingly formed web-shaped connecting element can be achieved by a corresponding material weakening the advantage that less material is required for the production of the light guide plate. The light guide plate may be lighter in weight and produced at a lower cost. Preferably, the cross-sectional area in the region of the first end and / or the further end of the web-shaped connecting element by at least 5%, preferably reduced by at least 10%, particularly preferably 30% to 70% relative to the cross-sectional area of the central portion of the web-shaped connecting element. Even a slight transverse surface eduction can lead to an improved displaceability of the layers relative to one another. It is understood here that the maximum reduction in cross-sectional area may depend on the light guide plate to be produced. In particular, it is understood that it must always be ensured that, despite a weakening of the material, the light guiding plate remains sufficiently stable. As already described, the position of the web-shaped connecting elements in relation to the first and the second layer is (deliberately) changed by the relative displacement. In particular, the web-shaped connecting elements between a vertical position with respect to the two layers and a (nearly) parallel position can be adjusted with respect to the two layers. According to a preferred embodiment of the present light guide plate, an angle between the first layer and the web-shaped connecting element between 5 ° and 175 °, preferably between 25 ° and 155 °, be adjustable by the relative displacement of the first layer to the second layer in the longitudinal direction. By a specific adjustment of the angle, not only a specific function can be switched on and off, but also the effect or the degree of the function can be specifically regulated. The set angle is essentially the same for all bar-shaped connecting elements. For example, the transmission of radiation from a maximum value to a minimum value (continuous) can be granted. As already described, the position of all the connection elements of a layer is changed in parallel.

Transmission properties are, for example, the reflectivity of the light guide plate, the transmissivity of the light guide plate, the property of deflecting rays in a certain way, etc. For a modification, for example, a special choice of material can be made and in particular a different material for the web-shaped connecting elements used as for the layers.

Alternatively or additionally, a web-shaped connecting element, preferably all web-shaped connecting elements of a layer, can be coated. A coating may comprise, for example, UV absorbers or pearlescent pigments. By modifying all web-shaped connecting elements of a layer can by changing the position of this Steglormigen connecting elements in a simple manner a specific function or property of the light guide plate can be changed.

Alternatively or additionally, a web-shaped connecting element, preferably all bar-shaped connecting elements of a layer, may be colored. For example, a coloration can influence the (sun) radiation transmission through the light guide plate.

Alternatively or additionally, a web-shaped connecting element, preferably all web-shaped connecting elements of a layer, can have a predefinable structure. By way of example, the web-shaped connecting elements can have a lens structure in order to direct (direct) incident light beams. Fresnel lens structures may be provided.

In addition, according to a further embodiment, the light guide plate may also have a plurality of layers with differently modified web-shaped connecting elements. In a light guide plate different transmission properties can be changed by changing the position of the web-shaped connecting elements of a particular position.

According to a further embodiment of the invention, the light guide plate may be formed by extrusion. The web-shaped Verbindungselem duck can be formed by undercutting. It has been recognized that a material weakening at the ends of the web-shaped connecting elements can be generated in a simple manner by an undercut. For this purpose, in particular special nozzles, which allow undercutting, can be used.

The light guide plate may include an actuator, such as a hydraulic or electric motor, or be connectable to an actuator. For example, the light guide plate may be inserted in a frame, wherein in the frame at least one actuator may be arranged. According to a further embodiment of the light guide plate according to the invention, at least the first layer and / or the second layer can be operatively connected to at least one actuator in such a way that a force can be transmitted from the at least one actuator to the first layer and / or the second layer. By means of at least one actuator, it is possible to set a specific displacement. In particular, a specific angle between the web-shaped connecting elements and a layer can be adjusted in a targeted manner in order to at least enhance or reduce at least one specific transmission characteristic of the light guide plate. Furthermore, control means comprising processor means and storage means for Activation of the at least one actuator may be provided. It is understood that at least one actuator can be provided for each layer to be actuated.

In principle, a light guide web plate can have more than two layers or belts connected via web-shaped connecting elements. According to one embodiment of the light guide plate according to the invention, the light guide plate may comprise at least one further layer. The further layer may preferably with the first layer or the second layer over a more / ah! be connected by further web-shaped connecting elements. Thus, a top chord, a center chord and a bottom chord can be provided.

The further web-shaped connecting elements may be formed in accordance with the web-shaped connecting elements described above. In other words, the position of the further web-shaped connecting elements can be specifically adjusted by a relative movement of the further layer to the first or second layer in a longitudinal direction. For example, the web-shaped connecting elements of the two layers can be modified differently in order to realize by a shift different functions or transmission properties of the light guide plate.

Furthermore, according to a further embodiment of the light guide plate according to the invention, the further web-shaped connecting elements can be arranged fixedly between the further layer and the first layer or the second layer. For example, fixed bar-shaped connecting elements, that is to say connecting elements which can not change their position, can be produced in that the ends of a bar-shaped connecting element have no weakenings or even thickenings. In other words, the connection regions between a layer and a web-shaped connecting element can have a uniform material thickness or even a material reinforcement. The cross-sectional area in the end regions of the other web-shaped connecting elements may be equal to or even increased in comparison to the cross-chnitts surface in the central portion. By forming an additional layer comprising a further layer and a plurality of further fixed web-shaped connecting elements, the stability of the light guide plate can be improved.

It is understood that a light guide plate may have further layers or straps, which may be connected via a plurality of fixed or non-fixed web-shaped connecting elements with other layers. In addition, thermoplastics can be used to make the light guide plate. For example, polycarbonate, polystyrene, polymethyl methacrylate, polyethylene, polypropylene, polyvinyl chloride, polyester, acrylbutadiene styrene and blends thereof can be used. According to a preferred embodiment of the plate according to the invention, at least one layer and / or the plurality of web-shaped connecting elements can be formed from a transparent plastic, in particular from polycarbonate.

Suitable polycarbonates are, for example, polycarbonates as described in the publications WO 2007/039130 and WO 2007/039131. These are homopolycarbonates, copolycarbonates and thermoplastic polyestercarbonates. The preparation of the polycarbonates is preferably carried out by the interfacial process of Dihydroxyarylverbindungen (hereinafter also referred to as diphenols) and phosgene or the melt transesterification of diphenols and Diarylcarbonatderivaten.

Preferred diphenols are selected from the group comprising resorcinol, 4,4'-dihydroxydiphenyl, bis- (4-hydroxyphenyl) -diphenyl-methane, 1,1-bis- (4-hydroxyphenyl) -1-phenyl-ethane, bis ( 4-hydroxyphenyl) -1- (1-naphthyl) ethane, bis (4-hydroxyphenyl) -1- (2-naphthyl) ethane, 2,2-bis (4-hydroxyphenyl) propane , 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) -propane, 1,1-bis (4-hydroxyphenyl) -cyclohexane, 1,1-bis- (3,5-dimethyl-4 -hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 1,1'-bis (4-hydroxyphenyl) -3-diisopropylbenzene and Ι. Γ-bis (4-hydroxyphenyl) -4-diisopropylbenzene. Mixtures of the diphenols can also be used. Particularly preferred are 4,4'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) -propane or bis (4-hydroxyphenyl) -3,3,5-trimethyl-cyclohexane or mixtures thereof.

For the preparation of copolycarbonates, it is also possible to use from 1 to 25% by weight, preferably from 2.5 to 25% by weight (based on the total amount of diphenols to be used), of hydroxy-aryloxy-endblocked polydiorganosiloxanes.

Also suitable are polyester carbonates and block copolyestercarbonates, especially as described in WO 2000/26275. Aromatic dicarboxylic acid dihalides for the preparation of aromatic polyester carbonates are preferably the diacid dichlorides of isophthalic acid, terephthalic acid, diphenyl ether-4,4'-dicarboxylic acid and naphthalene-2,6-dicarboxylic acid. Polydiorganosiloxane-polycarbonate block copolymers are distinguished by the fact that they contain on the one hand aromatic carboxylate units in the polymer chain and on the other hand polydiorganosiloxanes containing aryloxy end groups (eg US Pat. No. 3,189,662, US Pat. No. 3,821,325 and US Pat. No. 3,832,419).

Suitable polycarbonates preferably have average molecular weights M _{w V} on 18,000 to 40,000, preferably from 20,000 to 36,000 and in particular from 23,000 to 33,000. Weight average molecular weights Mw are each determined by gel permeation chromatography and polycarbonate standard calibration.

The polycarbonates generally have MFR (melt flow rate (values of 2 to 60 g / 10 min, preferably 2 to 40 g / 10 min, more preferably 3 to 18 g / 10 min, in particular from 5 to 13 g / 10 min measured in accordance with ISO 1133 at a temperature of 300 ° C and a load of 1.2 kg.

According to a further embodiment, a polycarbonate layer of the light guide plate conventional processing aids, in particular mold release agents and flow agents as well as for

Polycarbonates contain conventional stabilizers, in particular thermal stabilizers. Suitable stabilizers are, for example, phosphines, phosphites or Si-containing stabilizers and further compounds described in EP-A 0 500 496. Exemplary are triphenyl phosphites, diphenylalkyl phosphites, phenyl dialkyl phosphites, tris (nonylphenyl) phosphite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene diphosphonite, bis (2,4-dicumylphenyl) petaerythritol diphosphite and tri - called aryl phosphite. Particular preference is given to triphenylphosphine and tris (2,4-di-tert-butylphenyl) phosphite.

Suitable mold release agents are, for example, the esters or partial esters of monohydric to hexahydric alcohols, in particular of glycerol, of pentaerythritol or of guerbet alcohols.

Monohydric alcohols are, for example, stearyl alcohol, palmityl alcohol and Guerbet alcohols, a dihydric alcohol is, for example, glycol, a tetrahydric alcohol is, for example, glycerol, tetrahydric alcohols are, for example, pentaerythritol and mesoerythritol, pentahydric alcohols are, for example, arabitol, ribitol and xylitol; hexahydric alcohols are, for example, mannitol, glucitol ( Sorbitol) and dulcite. The esters are preferably the monoesters, diesters, esters, tetraesters, pentaesters and hexaesters or mixtures thereof, in particular random mixtures, of saturated, aliphatic C 10 to C 16 monocarboxylic acids and optionally hydroxy monocarboxylic acids, preferably with saturated, aliphatic C 1 to C 32 monocarboxylic acids and optionally hydroxy-monocarboxylic acids,

The commercially available fatty acid esters, in particular of pentaerythritol and of glycerol, may contain <60% of different partial esters as a result of the preparation.

Saturated aliphatic monocarboxylic acids having 10 to 36 C atoms are, for example, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, hydroxystearic acid, arachic acid, behenic acid, lignoceric acid, cerotic acid and montanic acids.

UV absorbers which can be used to modify at least the compound members according to a preferred embodiment are derivatives of biphenyl triazine, benzotriazoles, oxalanilides or hydroxybenzophenones. Particularly preferred biphenyltriazines are those of the following formula (IV) used,

where X is OR ⁶ , OCH ₂ CH ₂ OR ⁶ , OCH ₂ CH (OH) CH ₂ OR ⁶ or OCH (R ⁷ ) COOR ⁸ preferably OCH (R ⁷ ) COOR ⁸ , R "= branched or unbranched C ₁ -C ⁶ Alkyl, C ₂ -C ₂₀ -alkenyl, C ₆ -C ₂ -aryl or -CO-Ci-Ci8-alkyl, R = 1 1 or branched or unbranched Ci-Cs-alkyl, preferably CH 3 and R ⁸ = Ci C _{! 2} alkyl; C ₂ -C _{! 2} alkenyl or C ₅ -C ₆ cycloalkyl, preferably CgH _{! 7} .

Is particularly preferred as component C is a UV absorber of the formula (IV) with X = OCH (R ⁷⁾ COOR ^8, R = CH ₃ and R ⁸ = C ₈ H ₁₇ (UV absorber Tinuvin ^® 479 from BASF SE ) used. The biphenyl-substituted triazines of the general formula (IV) are known from WO-A 96/28431; DE-A 197 39 797; WO-A 00/66675; US 6,225,384; US 6,255,483; EP-A 1 308 084 and DE-A 101 35 795 known in principle. In a preferred embodiment, the UV absorbers have a high UV absorption in the range of the greatest sensitivity of the second layer, particularly preferably the UV absorbers have a UV absorption maximum between 300-340 μm.

UV absorbers from the class of benzotriazoles are for example, Tinuvin ^® 171 (2- [2-hydroxy-3-dodecyl-5-methylbenzyl) phenyl] -2H-benzotriazole (CAS No. 125304-04-3), Tinuvin ^® 234 ( 2- [2-hydroxy-3,5-di (1, 1-dimethylbenzyl) phenyl] -2H-benzotriazole (CAS No. 70321-86-7)), Tinuvin ^® 328 (2-2 [hydroxy- 3.5 -di-tert-amyl-phenyl) -2H-benzotriazole (CAS No. 25973-55-1).

UV absorbers from the class of oxanilides are, for example Sanduvor ^® 3206 (N- (2-ethoxyphenyl) - -ethanediamide (CAS No. 82493-14-9)) from Clariant or N- (2-ethoxyphenyl) -N '- (4 - dodecylphenyl) oxamides (CAS No. 79102-63-9).

UV absorbers from the class of hydroxybenzophenones are, for example Cimasorb ^® 81 (2-benzoyl-5- octyloxyphenol (CAS No. 1843-05-6) manufactured by Ciba Specialty Chemicals, 2,4-Dihydroxybenzo- phenone (CAS No. 131- 56-6), 2-hydroxy-4- (n-octyloxy) benzophenone (CAS No. 1843-05-6), 2-hydroxy-4-dodecyloxybenzophenone (CAS No. 2985-59-3).

UV absorbers from the class of triazines are, for example, 2- [2-hydroxy-4- (2-ethylhexyl) oxy] phenyl-4,6-di (4-phenyl) phenyl-1, 3,5-triazine, 2- [2-Hydroxy-4- [(octyloxycarbonyl) ethylidene] phenyl-4,6-di (4-phenyl) phenyl-1,3,5-tiazine, 2 - [2-hydroxy-4 - [3 - ( 2 - ethyl lhexyl- 1 - oxy) -2 - hydroxypropyloxyjphenyl] -4,6-bis (2,4-dimethylphenyl) - 1, 3, 5-triazine (CAS No. 137658-79-8) also known as Tinuvin ^® 405 (BASF SE), 2,4-diphenyl-6- [2-hydroxy-4- (hexyloxy) phenyl] -l, 3,5-triazine (CAS No. 147315-50-2) available as Tinuvin ^® (1577 BASF SE). The compound 2- [2-hydroxy-4- (2-ethylhexyl) oxy] phenyl-4,6-di (4-phenyl) phenyl-1,3,5-triazine has CAS NO. 204848-45-3 and is available from BASF SE under the name Tinuvin ^® 479. The compound 2- [2-hydroxy-4- [(octyloxycarbonyi) ethylidenoxy] phenyl-4,6-di (4-phenyl) phenyl-l , 3,5-triazine has the CAS No. 204583-39-1 and is available from BASF SE under the name CGX-UVA006.

UV absorbers are generally used in an amount of 0.01 to 5% by weight, preferably 0.01 to 2% by weight, particularly preferably 0.01 to 0.05% by weight. As dyes or pigments, for example, organic or inorganic pigments or organic dyes or the like can be used. Sulfur-containing pigments such as cadmium red and cadmium yellow, iron cyanide-based pigments such as Berlin blue, oxide pigments such as titanium dioxide, zinc oxide, red iron oxide, black iron oxide, chromium oxide, titanium yellow, zinc-iron-based brown, titanium cobalt-based green can be used as inorganic pigments , Cobalt blue, copper chrome based black and copper iron based black or chrome based pigments like chrome yellow. Preferred organic pigments or dyes are, for example, from the group of anthraquinones, perinones or on phthaloperinones or phthalocyanines derived dyes such as copper phthalocyanine blue and copper phthalocyanine green, condensed polycyclic dyes and pigments such as azo-based (eg nickel -Azogelb), sulfur indigo Dyes, perynone-based, piperylene-based, quinacridone-derived, dioxazine-based, isoindolinone-based and quinophthalone-derived derivatives, anthraquinone-based, heterocyclic systems, etc. Of these, cyanine derivatives, quinoline derivatives, anthraquinone derivatives, phthalocyanine derivatives are preferred. Specific examples of commercial products would be, for example, MACROLEX Blue RR®, MACROLEX Violet 3R®, MACROLEX Violet B® (Lanxess AG, Germany), Sumiplast Violet RR, Sumiplast Violet B, Sumiplast Blue OR, (Sumitomo Chemical Co., Ltd.), Di aresin Violet D, Diaresin Blue G, Diaresin Blue N (Mitsubishi Chemical Corporation), Heliogen Blue or Heliogen Green (BASF AG, Germany).

In addition, according to another embodiment, the outer surfaces of the lightguide web plates may have additional functionality as desired (e.g., UV stabilization, color design, matting, IR reflection, etc.), e.g. by applying layers by means of coextrusion or by coating / coating.

The method for applying additional layers of polycarbonate on one or both surfaces of the layers, in particular the upper or lower chords, is known in the art. The coating layers may comprise, for example, UV absorbers or pearlescent pigments. These can be applied by coextrusion or by painting or by reverse roll coating.

In a preferred embodiment, the light guide plate may be formed translucent. The term "translucent" refers essentially to the visible spectral range. For characterization, the wavelength range of 380 to 780 nm, in particular the wavelength of 550 nm. The translucency, which is denoted here by T, is in the scientific Literature predominantly symbolized with xD65. The thermoplastic material and optionally the coating of the plate preferably have a light transmission T of at least 5%, preferably 20 to 94%. The light transmittance here is preferably adjustable between the limit values due to the relative displaceability of the at least two layers.

Another aspect of the invention is a glazing system comprising at least one light guiding plate described above. The glazing system can also comprise more than one Lichtfuhrungsplatte, which can be arranged side by side and / or one above the other or behind each other.

It is understood that the light guide plate described above can also be used in roof or wall systems.

Yet another aspect of the invention is a use of a plate, in particular a web plate, comprising a first layer, at least one second layer, wherein the first layer is connected to the second layer via a plurality of web-shaped connecting elements, wherein the web-shaped connecting elements with the first Layer and the second layer are connected such that the first layer is displaceable relative to the second layer in at least one longitudinal direction, in a glazing system as a variable adjustable light pipe. In particular, a light guide plate described above can be used.

There are now a variety of ways to design the light guide plate according to the invention, the glazing system according to the invention and the inventive use of a light guide plate and further develop. For this purpose, reference is made, on the one hand, to the claims subordinate to the independent patent claims, and, on the other hand, to the description of exemplary embodiments in conjunction with the drawing. In the drawing shows:

Fig. 1a is a schematic view of a first embodiment of a

Light guide plate according to the present invention in a first position,

1 b is a schematic view of the first embodiment of a light guide plate according to the present invention in a further position, a schematic view of the first embodiment of a light guide plate according to the present invention in yet another position, Fig. 2 is a schematic view of a detail of the first exemplary embodiment of a light guide plate according to the present invention, Fig. 3a is a further schematic view of another exemplary embodiment of a

Light guide plate according to the present invention in a first position, and

Fig. 3b is a further schematic view of the further exemplary embodiment of a

Light guide plate according to the present invention in a further position.

Hereinafter, like reference numerals are used for the same elements.

Figure l a shows a schematic sectional view of a first exemplary embodiment of a light guide plate 2 according to the present invention in a first position. The illustrated light guide plate 2 is in particular a Lichtfuhrungsstegplatte 2. The illustrated web plate 2 comprises a first layer 4, such as a top flange 4th and a second layer 6, such as a lower flange 6. The upper flange 4 is connected to the lower flange 6 via a A plurality of web-shaped connecting elements 8 are connected. Between the web-shaped connecting elements 8 and the layers 4, 6 cavities 10 are formed, which are preferably filled with a gas, such as air. For example, the first and / or the second layer have a thickness in the range between about 0.5 mm and 2 mm and the web-shaped connecting elements have a height of 10 mm to 18 mm.

It is understood that the said elements can also have other dimensions.

Preferably, the illustrated light guide plate 2 is formed transparent and / or translucent. In particular, the light guide plate 2 may be formed of a transparent plastic such as polycarbonate. It is understood that other materials may be used. The light guide plate 2 can be used in particular in glazing systems.

As can be seen from FIG. 1 a, the web-shaped connecting elements 8 are perpendicular to the first layer 4 and the second layer 6 in the first position. In other words, an angle 12 of 90 ° exists between the web-shaped connecting elements 8 and the layers 4, 6 set. In particular, the angle 12 is set to 90 ° in all web-shaped connecting elements 8. The illustrated light guide plate 2 is characterized in that the layer 4 is displaceable relative to the further layer 6 in a longitudinal direction 14. A longitudinal direction in this case means in a direction orthogonal to the wide surfaces of the web-shaped connecting elements 8. It should be noted that the web-shaped connecting elements 8 are arranged parallel to each other.

FIG. 1b shows, by way of example, the first exemplary embodiment of the light guide plate 2 according to the present invention in a further position. As can be seen, the first layer 4 is displaced in a longitudinal direction 14a and the further layer 6 in the opposite longitudinal direction 14b. So there is a parallel shift of the layers 4 and 6.

The relative displacement can be effected by actuators (not shown). For example, electric motors may be provided which may be suitably connected to the respective layer 4, 6 in order to transmit a force to the respective layer 4, 6. In addition, a controller may be provided, which controls the actuators. The controller can be manually adjusted by a user. Alternatively or additionally, setpoint values can be preset, the exceeding or falling below of which by detected actual values causes an automatic actuation, that is to say displacement of the layers. For example, suitable sensors, such as temperature sensors, radiation sensors, timers, may be provided for detecting the actual values.

It is understood that only the first layer 4 or only the second layer 6 can be displaced while the respective other layer 4, 6 is fixed or not actuated. The relative displacement of the first layer 4 relative to the further layer 6 causes inter alia that all web-shaped connecting elements 8 are tilted uniformly. Thus, all web-shaped connecting elements 8 are tilted or inclined in the same direction. In the position shown in FIG. 1b, an angle 12 of approximately 45 ° is set between the web-shaped connecting elements 8 and the layers 4.

By the above-described change in the position of the web-shaped connecting elements 8 in relation to the layers 4 and 6, at least one transmission property of the light guide plate 2 can be selectively changed. Exemplary properties that can be changed are the light transmission of the light guide plate 2, the transmission characteristics with respect to the global radiation of the light guide plate 2, the selectivity index (SKZ) of the light guide plate 2, the shading coefficient of the light guide plate 2, etc. In particular, the (sun) Strahlauftrefffläcbe on the broad surfaces of the web-shaped connecting elements 8 of an incident radiation can be changed 1 8. For example, the light transmission of solar radiation 18 can be increased by tilting all the web-shaped connecting elements 8 according to the figure lb. As can be seen, the web-shaped connecting elements 8 are substantially parallel to the incident S onnenstrah ment 1 8 aligned. The impact area has thus been significantly reduced. Figure lc shows a schematic view of the first embodiment of the light guide plate 2 according to the present invention in a further position. As can be seen, the first layer 4 and the further layer 6 are displaced relative to one another in a longitudinal direction 14. In this position, the first layer 4 is displaced in a longitudinal direction 14b and the further layer 6 in the opposite longitudinal direction 14a. As a result, the web-shaped connecting elements 8 are tilted uniformly. Thus, all web-shaped connecting elements 8 are tilted or inclined in the same direction. In the present position, an angle 12 of approximately 135 ° is set between the web-shaped connecting elements 8 and the layers 4, 6.

By a corresponding tilting of the web-shaped connecting elements 8, the light transmission of solar radiation 18 can be reduced in the present position. The reason for this is that the tilted web-shaped connecting elements 8 are aligned substantially orthogonal to the incident S nnenstrahlung. The impact area has therefore been significantly increased. Basically, the angle 12 between about 5 ° and about 1 75 "set and a corresponding tilting of the web-shaped connecting elements 8 are effected.

Furthermore, the web-shaped connecting elements 8 can be specifically modified to achieve certain properties and / or to reinforce or reduce. For example, the web-shaped connecting elements 8 may be colored or coated. As a result, absorption properties or reflection properties can be changed. For example, a reflective layer may be applied or a dark color may be introduced. The web-shaped connecting elements 8 may also have a specific structure, such as a lens structure, in order to specifically redirect or deflect the incident light. An exemplary lens structure is a Fresnel lens structure. As already described, the versatility of the first layer 4 relative to the at least one further layer 6 can be achieved by different measures. In particular, the ends of the web-shaped connecting elements 8, that is to say the regions connected to the respective layer 4, 6, can be made more flexible than a middle section of the web-shaped connecting elements 8. It is conceivable to use a more flexible material at the ends than in the middle section.

Another possibility is shown in FIG. FIG. 2 shows a schematic view of a detail 16 of the first exemplary embodiment of a light guide plate 2 according to the present invention. Shown is in particular a web-shaped Verbindungssei ement 8, which is connected to the first layer 4 and the second layer 6.

The illustrated web-shaped connecting element 8 has a middle section 20 and a first end 22a and a further end 22b. At the first end 22a, ie in the connection region with the first layer 4, the web-shaped connecting element 8 has a taper 24a or a material recess 24a. In a corresponding manner, the further end 22b has a taper 24b or a material recess 24b. In particular, the cross-sectional area at one end 22a, 22b of the web-shaped connecting element 8 is formed at least smaller than the cross-sectional area in the middle section 20 of the web-shaped connecting element 8. For example, the cross-sectional area at one end 22a, 22b may be 5%, preferably at least 10%, particularly preferred be reduced by 30% to 70%.

The contour of the recess 24a, 24b can be arbitrarily shaped. For example, a step-like or dreie k-shaped recess can be formed. Preferably, a curved recess 24a, 24b or taper 24a, 24b is formed. Also, a material recess may at least partially extend into the respective layer 4, 6.

Already by a slight reduction in material, the flexibility at the ends 22a, 22b can be increased such that a displaceability of the first layer 4 relative to the second layer 6 in a longitudinal direction 14 is possible. In particular, a tilting of the web-shaped connecting elements 8 can be achieved. It is understood that for a stable light guide plate 2, the flexibility and thus the matrix at the ends 22a, 22b must not be too large to further obtain a stable light guiding plate 2.

It should be noted that the possible cross-sectional area reduction or material reduction of parameters of the light guide plate 2, such as number of connecting elements 8, thickness of the layers 4, 6, thickness of the connecting elem duck 8, length of the connecting elements 8, material of the connecting elements 8 and / or Layers 4, 6, number of layers and the like may depend. FIG. 3a shows a further schematic view of a further embodiment of a light guide plate 2.1 according to the present invention in a first position. Compared to the plate 2 of the first exemplary embodiment (see FIGS. 1 a, 1 b), the light guide plate 2. 1 has a further layer 26 according to FIG. The further layer 26 represents the bottom flange in the illustrated double-web plate 2.1 of the present embodiment, while the layer 4.1 represents a top flange 4.1 and the layer 6.1 represents a center belt 6.1.

The middle layer 6.1 is connected via further web-shaped connecting elements 8.1 with the further layer 26. In the first position, which can also be regarded as a starting position, an angle 12, 12.1 of 90 ° is set.

FIG. 3 b shows a further schematic view of the further exemplary embodiment of the light guide plate 2.1 according to the present invention in a further position. As can be seen, the first layer 4.1 has been displaced in a longitudinal direction 14a relative to the second layer 6.1. In this case, only the first layer has been displaced in a longitudinal direction 14a, while the further layers 26 and 6.1 have not been displaced. In this case, an angle 12 of approximately 45 ° can be set while the angle 12.1 is still 90 °.

In order to enable a shift of the layer 4.1, for example, the web-shaped connecting elements 8 of the upper layer can have tapers at their ends corresponding to FIG. In order to achieve beyond that the layers 6.1 and 26 are immovable, the further web-shaped connecting elements 8 between the layers can be formed 6.1 and 26 fixed. For example, the web-shaped connecting elements 8.1 of the lower layer can have no weakenings or even thickenings at their ends. As a result, the flexibility is reduced in the region of the ends of the web-shaped connecting elements 8.1, so that a displacement of the second layer 6.1 to the other layer 26 is not given. It is understood that, according to further variants of the invention, further layers can be provided, which can be displaceable or not displaceable relative to each other. In addition, it is understood that the web-shaped connecting elements of different layers can be arranged offset from one another.

Furthermore, according to a further variant of the invention, a plurality of layers may be provided, wherein the web-shaped connecting elements of one layer may be differently modified in comparison to the web-shaped connecting elements of another layer. For example, the web-shaped connecting elements of a first layer may be coated, while the web-shaped connecting elements of another layer may have a specific tarbung egg. By tilting the web-shaped connecting elements of the first layer, the light guide plate can be changed with respect to a first transmission property, while by tilting the web-shaped connecting elements of the further layer another transmission property of the light guide plate can be changed.

Claims

claims

1. light guide plate (2, 2.1), in particular light guide web plate (2, 2.1), comprising:

a first layer (4, 4.1), and

- At least a second layer (6, 6.1), wherein the first layer (4, 4.1) via a

A plurality of web-shaped connecting elements (8) is connected to the second layer (6, 6.1),

characterized in that

at least one web-shaped connecting element (8) is modified such that the web-shaped connecting element (8) at least one predetermined

Has transmission property, and

the web-shaped connecting elements (8) are connected to the first layer (4, 4.1) and the second layer (6, 6.1) in such a way that the first layer (4, 4.1) moves into at least one relative to the second layer (6, 6.1) Longitudinal direction is displaceable,

- By the relative displacement, the position of the web-shaped connecting elements

(8) is uniformly changeable with respect to the first layer (4, 4.1) and the second layer (6, 6.1).

2. light guide plate (2, 2.1) according to claim 1, characterized in that by the relative displacement, the position of the web-shaped connecting elements (8) with respect to the first layer (4, 4.1) and the second layer (6, 6.1) changeable is that one

Strahlenauftrefffläche on a surface of a web-shaped connecting element (8) is changeable.

3. light guide plate (2, 2.1) according to claim 1 or 2, characterized in that a web-shaped connecting element (8) has a central portion (20), a first with the first layer (4, 4.1) connected end (22 a) and another with the second layer (6, 6.1) has connected end (22b), wherein at least one end (22a, 22b) of the web-shaped connecting element (8) has at least a higher flexibility than the central portion (20) of the web-shaped connecting element (8).

4. light guide plate (2, 2.1) according to claim 3, characterized in that

the web-shaped connecting element (8) has a taper (24a) in the region of the first end (22a),

and or the stegtonn ige connecting element (8) in the region of the further end (22b) has a taper (24b).

5. light guide plate (2, 2.1) according to claim 4, characterized in that the

Cross-sectional area in the region of the first end (22a) and / or the further end (22b) of the web-shaped connecting element (8) by at least 5%, preferably by 30% to 70% relative to the cross-sectional area of the central portion (20) of the web-shaped

Connecting element (8) is reduced.

6. light guide plate (2, 2.1) according to one of the preceding claims, characterized in that an angle (12) between the first layer (4, 4.1) and the web-shaped

Connecting element (8) between 5 ° and 175 °, preferably between 25 ° and 155 °, by the relative displacement of the first layer (4, 4.1) to the second layer (6, 6.1) in

Longitudinally adjustable.

7. light guide plate (2, 2.1) according to one of the preceding claims, characterized in that

at least one web-shaped connecting element (8) is coated,

and or

at least one web-shaped connecting element (8) is colored,

and or

at least one web-shaped connecting element (8) has a predeterminable structure.

8. light guide plate (2, 2.1) according to one of the preceding claims, characterized in that the light guide plate (2, 2.1) is formed by extrusion, wherein the web-shaped connecting elements (8) are formed by undercut.

9. light guide plate (2, 2.1) according to one of the preceding claims, characterized in that at least the first layer (4, 4.1) and / or the second layer (6, 6.1) is connectable to at least one actuator, such that a force of which at least one actuator is transferable to the first layer (4, 4.1) and / or the second layer (6, 6.1).

10. light guide plate (2, 2.1) according to one of the preceding claims, characterized in that the light guide plate (2, 2.1) has at least one further layer (26), wherein the further layer (26) is connected to the first layer (4, 4.1) or the second layer (6, 6.1) via a plurality of further web-shaped connecting elements (8.1).

11. Light guide plate (2, 2.1) according to claim 10, characterized in that the further web-shaped connecting elements (8.1) fixedly arranged between the further layer (26) and the first layer (4, 4.1) or the second layer (6, 6.1) are.

Light guide plate (2, 2.1) according to one of the preceding claims, characterized in that at least one layer (4, 4.1, 6, 6.1, 26) and / or the plurality of web-shaped connecting elements (8, 8.1) made of a transparent plastic, in particular Polycarbonate, are formed.

Glazing system comprising at least one light guide plate (2, 2.1) according to one of the preceding claims.

Use of a light guide plate, in particular a light guide web plate, comprising a first layer (4, 4.1), at least one second layer (6, 6.1), wherein the first layer (4, 4.1) via a plurality of web-shaped connecting elements (8) with the second layer (6, 6.1) is connected, wherein the web-shaped connecting elements (8) with the first layer (4, 4.1) and the second layer (6, 6.1) are connected such that the first layer (4, 4.1) relative to the second Layer (6, 6.1) is displaceable in at least one longitudinal direction, wherein the relative displacement of the position of the web-shaped

Connecting elements (8) with respect to the first layer (4, 4.1) and the second layer (6, 6.1) is uniformly changeable in a glazing system for variable light pipe.