MXPA98007693A - Amorfa plate of a polyalycylene naftalate crystallized - Google Patents

Abstract

The invention relates to an amorphous plate having a thickness of 1 to 20 mm and characterized in that its main component is at least one polyalkylene naphthalate, the invention further relates to a process for producing this pla

Description

AMORFA DE ON AFTALATO DE PO IAOÜILE? CRYSTALLIZABLE PLATE DESCRIPTIVE MEMORY The invention relates to an amorphous plate of at least one crystallizable polyalkylene naphthalate, the thickness of which is in the range of 1 to 2 mm. The plate is distinguished by very good optical and mechanical properties. The invention also relates to a process for the production of this plate. The amorphous sheets having a thickness between 1 and 20 iran are sufficiently known. These plate-like structures are made of amorphous, non-crystallizable thermoplastic materials. Typical examples of such thermoplastic materials that are shaped as plates are, for example, polyvinyl chloride (PVC), polycarbonate (PC) and. polymethylene methacrylate (PMMA). These finished products are produced in the so-called extrusion lines (see Polymer erkstoffe [Polymer Materials], volume II, Technology, 1 page 136, Georg Thieme, Sttugart, 1984). The powdery or granular starting material is melted in an extruder. After extrusion, the amorphous thermoplastic materials can be easily reconfigured by polishing stacks or other configuration molds as a result of constantly increasing viscosity with decreasing temperature.

After setting, the amorphous thermoplastic materials then have adequate stability, i.e. high viscosity in order to "stand on their own" the calibration mold. However, they are still soft enough to be configured by the mold. The viscosity of the molten bath and the internal stiffness of the amorphous thermoplastic materials in the calibration mold is so high that the semi-finished product does not deteriorate before it is cooled in the calibration mold. In the case of easily decomposable materials, such as, for example, PVC, particular processing aids, such as, for example, anti-decomposition treatment stabilizers and lubricants against too high internal friction and therefore Uncontrollable heating, are needed during extrusion. External lubricants are necessary to prevent the material from adhering to the walls and rollers. In the treatment of PMMA, for example, the devolatilizer extruder is used for the purpof removing moisture. In the production of plates of amorphous thermoplastic materials, high cost additives are sometimes necessary, which in some cases are displaced and can lead to production problems as a result of evaporation and deposits on the surface of the semi-finished product. PVC plates are difficult to recirculate or can only be recirculated with special neutralization or electrolysis procedures. The PC and PMMA sheets are equally difficult to recirculate and can be recirculated only with a loss or extreme deterioration of the mechanical properties. In addition to these advantages, PMMA plates also have extremely poor impact and chip resistance when fractured or under mechanical stress. In addition, PMMA plates are as combustible as wood, so they can not be used, for example, for interior applications and in exhibition construction. The PMMA and PC boards can not be configured in addition to cold. During the cold configuration, the PMMA plates are broken forming dangerous splinters. During the cold configuration of the PC plates, cracks the size of a hair and white fracture occur. EP-A-0 471 528 describes a method for configuring an object of a polyethylene terephthalate (PET) sheet. The PET sheet is heat treated on both sides in a thermal shaping mold in a temperature range between the glass transition temperature and the melting temperature. The shaped PET foil is removed from the mold when the degree of crystallization of the shaped PET foil is in the range of 25 to 50%. The PET plates described in EP-A 0 471 528 have a thickness of 1 to 10 mm. Since the thermally shaped shaped article, produced from this PET film is partially crystalline and therefore is no longer transparent and the properties of the surface of the shaped article is determined by the thermal shaping process and the temperatures and configurations given by this, the optical properties (for example brightness, turbidity and light transmission) of the PET plates used are of little importance. As a general rule, the optical properties of these plates are poor and require optimization. US-A-3,496, 143 describes the thermal vacuum forming of a 3 mm thick PET film, the crystallization of which must be in the range of 5 to 25%. The crystallinity in the shaped article, thermally shaped, is greater than 25%. On these PET plates also, no requirements are imposed with respect to the optical properties. Since the crystallinity of the plates used is between 5 and 25%, these plates are turbid and non-transparent. The object of the present invention is to provide an amorphous sheet having a thickness of 1 to 20 mm which has good mechanical properties and good optical properties. Good optical properties include, for example, high light transmission, high surface brightness, extremely low turbidity and high transparency, depending on the modality. The good mechanical properties include, among others, a high impact resistance and a high resistance to the f actures. In addition, the sheet according to the invention must be recirculated, in particular without loss of mechanical properties and low combustibility, so that, for example, it can also be used for interior applications and in display construction. This objective is achieved with an amorphous sheet having a thickness in the range of 1 to 20 mm, which contains, as a main constituent, at least one crystallizable polyalkylene naphthalate. The amorphous film contains, as the main constituent, at least one crystallizable polyalkylene naphthalate. Preference is given to polyethylene naphthalate polypropylene naphthalate and polybutylene naphthalate, with particular preference being given to polyethylene naphthalate (PEN). The amorphous sheet may be transparently colorful or opaquely colorful. In the transparent mode, the amorphous sheet has a surface brightness, measured in accordance with DIN 67530 (measurement angle 20 °), which is greater than 110, preferably greater than 120. The transmission of light, measured in accordance with ASTM D 1003, is greater than 80%, preferably greater than 82%, and turbidity of the sheet, also measured in accordance with ASTM D 1003, is less than 15%, preferably less than 11%. The clarity of the transparent sheet, determined at an angle of less than 2.5 ° (ASTM D 1003), is preferably greater than 90%, particularly preferably greater than 92%. In the transparently colored mode, the amorphous sheet contains at least one soluble dye. The concentration of soluble dye are preferably in the range of 0.001 to 20% by weight, based on the weight of the polyalkylene naphthalate. Soluble dyes are considered to mean substances that dissolve molecularly in the polymer (DIN 55949). The color change as a consequence of the dyeing of the amorphous sheet is based on the wavelength-dependent absorption and / or the diffusion of the light. Dyes can only absorb, not diffuse, light, since the physical prerequisite for diffusion is certain minimum particle size. Dyeing by means of dyes is a solution procedure. As a result of this solution procedure, the dye is dissolved molecularly, for example in the polymer PE ?. Reference is made to such dyes as transparent, or translucent or opalescent. Of the various kinds of soluble dyes, particular preference is given to the soluble fatty and aromatic dyes. These are, for example, azo and anthraquinone dyes. They are particularly suitable for dyeing the PEN, since, due to its high glass transition temperature of the PEN, the displacement of the dye is limited (J. Kroerner literature, soluble temples in the plastics industry in "VDI-Gesellschaft Kunststofftechnik: Einfárben von uststoffen, DVI Publishing, Dusseldorf 1975. Examples of suitable soluble dyes are: Solvent Yellow 93, a pyrazolone derivative, Solvent Yellow 16, a fat-soluble azo dye, Fluorol Green-Gold, a fluorescent polycyclic dye, Solvent Red 1, an azo dye, azo dyes such as Red Thermoplastic BS, Red Sudan BB, Red Solvent 138, a derivative of anthraquinone, fluorescent benzopyran dyes, such as Red Fluorol GK and Orange Fluorol GK, Blue Solvent 35, a dye of anthraquinone, Solvent Blue, a phthalocyanine dye and many others, mixtures of two or more of these soluble dyes are also suitable.In accordance with the invention, the soluble dye may have It has already been added in the desired concentration by the producer of the starting material or it can be added in the extruder during the production of the sheet.

However, the dye additive is added particularly preferably by the masterbatch technology. The soluble dye is dispersed and / or completely dissolved in a solid carrier material. Suitable carrier materials are certain resins, the polyalkylene naphthalate itself or alternatively other polymers which are sufficiently compatible with the polyalkylene naphthalate. It is important that the particle size and the bulk density of the masterbatch be similar to the particle size and the bulk density of the polyalkylene naphthalate, so that the homogeneous distribution and consequently the homogeneous transparent coloration can take place. The surface brightness of the transparently colored sheet, measured in accordance with DIN 67530 (measurement angle 20 °), is greater than 100, preferably greater than 110, light transmission, measured in accordance with ASTM D 1003, is in the range of 5 to 80%, preferably in the range of 10 to 70%, and the turbidity of the sheet, measured in accordance with ASTM D 1003, is in the range of 2 to 40%, preferably in the range of 3 to 35%. In the colorful mode, the amorphous sheet contains at least one organic and / or inorganic pigment as colorant. The concentration of the dye is preferably in the range of 0.5 to 30% by weight, based on polyalkylene naphthalate. When considering dyes, a distinction is made according to DIN 55944 between dyes and pigments. The pigments are virtually insoluble in the polymer under the respective treatment conditions, while the dyes are soluble (DIN 55949). The coloring action of the pigments is produced by the particles themselves. The term pigment is generally linked to a particle size of 0.01 μm to l.Oμm. According to DIN 53206, when the pigment particles are defined, a distinction is made between primary particles, aggregates and agglomerates. The primary particles that are generally produced in the synthesis have a pronounced tendency to aggregate as a result of their extremely small particle size. This produces, by aggregation of area of the primary particles, the aggregates, which thus have a surface area smaller than that corresponding to the sum of the surface area of their primary particles. As a result of the agglomeration of the primary particles and / or the aggregates and the corners and edges, agglomerates are formed, whose total surface area differs only little from the sum of the individual areas. If reference is made to the particle size of the pigment without further detailed indications, this refers to the aggregates that are essentially present after the coloration.

In the pigments that are in powder form the aggregates are always joined to form agglomerates, which during the coloring process must be discarded, moistened by the polymer and homogeneously distributed. These procedures that occur simultaneously are called dispersion. In the case of coloring with dyes, on the other hand, the indicated procedure is one of solution, as a result of which the dye is present in molecularly dissolved form. In contrast to the inorganic pigments, in the case of certain organic pigments the complete insolubility is not the case, especially not in the case of the pigments of simple composition having low molecular weights. The dyes are adequately described by their chemical structure. The pigments that are in each case of identical chemical composition, however, can be prepared and exist in different crystal modifications. A typical example of this is titanium dioxide of white pigment, which may exist in the form of rutile and in the form of anatase. In the case of pigments it is possible, by coating, that is by subsequently treating the surface of the particles with pigment, by using organic or inorganic agents, to improve the properties of utility. This improvement consists in particular in facilitating dispersion and in increasing light stability and resistance to climatic changes and chemical products. Typical coating agents for pigments are fatty acids, fatty acid amides, siloxanes and aluminum oxides, for example. Examples of suitable inorganic pigments are titanium dioxide of white pigments, zinc sulphide and tin sulphide, which can be coated with organic and / or inorganic substances. The titanium dioxide particles may contain anatase or ethyl, but preferably predominately rutile which, in comparison with the anatase, exhibits greater opacity, in a preferred embodiment, at least 95% by weight of the titanium dioxide particles consist of rutile . They can be prepared by a usual procedure, for example by the chloride or sulphate process. The average particle size is relatively low and is preferably in the range of 0.10 to 0.30 μm. Using titanium dioxide of the type described, vacuoles are not formed within the polymer matrix during the production of the plates. The titanium dioxide particles may have a coating of inorganic oxides which are usually used as a coating for the white pigment of titanium oxide in papers or coating compositions, to improve the fixation of the light. It is known that the IO2 is photoactive. Under the action of ultraviolet rays free radicals are formed on the surface of the particles. These free radicals can travel to the film-forming constituents of the coating composition, leading to degradation reactions and to enamarillecimiento. Particularly suitable oxides include the oxides of aluminum, silicon, zinc or magnesium, or mixtures of two or more of these compounds. IO2 particles having a coating of two or more of these compounds are described, for example, in EP-A-0044 515 and in EP-A-0 078 633. The coating may also contain organic compounds having polar and apolar groups. . During the preparation of the sheet by extrusion of the molten polymer bath, the organic compounds must be of sufficient thermal stability. Examples of polar groups are -OH, -OR, -C00X (X = R, H or Na, R = alkyl having from 1 to 34 carbon atoms). Preferred organic compounds are alkanols and fatty acids having from 8 to 30 carbon atoms in the alkyl group, especially primary fatty acids and n-alkanols having from 12 to 24 carbon atoms, and also polydiorganosiloxanes and / or polyorganohydridosiloxanes, by example polydimethylsiloxane and polymethylhydrido siloxane. The coating on the titanium dioxide particles usually consists of 1 to 12 g, in particular from 2 to 6 g, of the inorganic oxides and from 0.5 to 3 g, in particular from 0.7 to 1.5 g, of the organic compound, based on 100 g of the titanium dioxide particles. The coating is preferably applied to the particles in aqueous suspension. The inorganic oxides are precipitated in the aqueous suspension of water-soluble compounds, for example alkali metal aluminate, especially sodium aluminate, aluminum hydroxide, aluminum sulfate, aluminum nitrate, sodium silicate (water glass) or silicic acid. . It should be understood that the term inorganic oxides, such as AI2O3 and SiO2, includes the hydroxides or their various stages of dehydration, for example hydrated oxides, without their precise composition and structure being known. The hydrated oxides, for example, of aluminum and / or silicon are precipitated on the pigment of IQ2 after calcining and milling in aqueous suspension, and the pigments are then washed and dried. This precipitation can therefore take place directly in a suspension that occurs in the synthesis process following the calcination and the subsequent wet milling. The precipitation of the oxides and / or the hydrated oxides of the respective metals takes place from the salts of water-soluble metals within the known pH range; for aluminum, for example, aluminum sulphate is used in aqueous solution (pH less than 4) and the hydrated oxide is precipitated by adding aqueous solution of ammonia or sodium hydroxide solution in the pH range of between 5 and 9, preferably between 7 and 8.5. Starting from a glass solution of water or alkali metal aluminate, the pH of the initially loaded TiO2 suspension must be in the strongly alkaline range (pH greater than 8). In this case, the precipitation is carried out by adding mineral acid such as sulfuric acid in the pH range of 5 to 8. Following the precipitation of the metal oxides, the suspension is subsequently stirred for 15 minutes to about 2 hours, during which time the which precipitated coatings undergo aging. The coated product is separated from the aqueous dispersion and, after washing, dried at elevated temperature, especially at 70 and up to 110 ° C. Typical inorganic black pigments are modifications of carbon black that can also be coated, carbon pigments that differ from carbon black pigments for a higher ash content, and black oxide pigments, such as black blends. of iron oxide and copper, and of chromium and iron oxide (pigments of mixed phase). Suitable inorganic color pigments are colorful oxide pigments, hydroxyl-containing pigments, sulfide pigments and chromates. Examples of colorful oxide examples are iron oxide red, mixed phase pigments titanium dioxide-nickel oxide-antimony oxide, pigments in mixed phase titanium dioxide-chromium oxide-antimony oxide, mixtures of iron, zinc and titanium oxides, chromium oxide-iron oxide coffee, spirals of the cobalt-aluminum-titanium-nickel-zinc oxide system, and pigments in mixed phase based on other metal oxides. Examples of typical hydroxyl-containing pigments are trivalent iron oxide hydroxides, such as FeOOH. Examples of sulfur pigments are cadmium sulfides-selenides, cadmium-zinc sulphides, sodium-aluminum silicate containing sulfur bound as polysulfide in the network. Chromates are examples of lead chromates, which may exist in monoclinic, rhombic and tetragonal crystal forms. All color pigments, such as black and white pigments, can be either uncoated or coated with inorganic and / or organic substances. The organic color pigments are generally divided into azo pigments and the so-called non-azo pigments. The characteristic feature of the azo pigments is the azo group (-N = N-). Azo pigments include monoazo pigments, diazo pigments, diazo condensation pigments, azo dye acid salts and mixtures of azo pigments. The amorphous colored sheet contains at least one inorganic and / or organic pigment. In specific embodiments, the amorphous sheet may also contain mixtures of inorganic and / or organic pigments, and also soluble dyes. In this context, the concentration of the soluble dye is preferably in the range of 0.01 to 20% by weight, and particularly preferably in the range of 0.5 to 10% by weight, based on the weight of the polyalkylene naphthalate. According to the invention, the dyes (pigments and, if desired, inorganic and / or organic dyes) may have already been added at the desired concentration by the producer of starting material or they may be added in the extruder during the production of the sheet. However, the color additive will be particularly preferably by the technology of the masterbatch or by the preparation of the solid pigment. The inorganic and / or organic pigment and, if desired, the soluble dye is completely dispersed in a solid carrier material. Suitable carriers are certain resins, the polymer to be colored itself or alternatively other polymers that are sufficiently compatible with the polyalkylene naphthalate. It is important that the particle size and the density of the preparation of the solid pigment and the masterbatch are similar to the particle size and the bulk density of the polyalkylene naphthalate, so that the homogeneous distribution and then the coloration take place. The surface brightness of the colorful sheet, measured in accordance with DIN 67530 (measuring angle 20 °), is preferably greater than 90 and the light transmission, measured in accordance with ASTM D 1003, is preferably less than 5%. The colored sheet also has homogeneous, opaque optical properties. In an even more preferred embodiment, the amorphous sheet further contains at least one ultraviolet stabilizer as a light stabilizer, the concentration of the ultraviolet stabilizer being preferably between 0.01 and 5% by weight, based on the weight of the polyalkylene naphthalate. The light, in particular the ultraviolet portion of the solar radiation, ie the wavelength range from 280 to 400 nm, indicates degradation procedures in the thermoplastic materials, as a consequence of which it does not change only the visual appearance, due to a color change or enamarillecimiento, but also adversely affect the physical and mechanical properties. The division of these processes of photooxidative degradation is of considerable industrial and economic importance, since otherwise the uses of numerous thermoplastic materials are drastically limited. Polyalkylene naphthalates, for example, begin to absorb ultraviolet light even at less than 360 nm, and their absorption increases considerably to less than 320 nm and is very pronounced at less than 300 nm. The maximum absorption is between 280 and 300 nm. In the presence of oxygen, mainly chain disintegration is observed but not entanglement. Carbon monoxide, carbon dioxide and carboxylic acids are the predominant photooxidation products in terms of quantity. In addition to the direct photolysis of the ester groups, the oxidation reactions that also result in the formation of carbon dioxide by peroxide radicals must also be taken into account. The photooxidation of the polyalkylene naphthalates can also result, by the disintegration of the hydrogen in the position Ó of the ester groups, to hydroperoxides and decomposition products thereof and in the associated chain disintegration (H. Day, DMiles, J. Appln, Polym, Sci 16, 1972 page 203). Ultraviolet stabilizers or ultraviolet absorbers as light stabilizers are chemical compounds that can intervene in the physical and chemical processes of light-induced degradation. Carbon black and other pigments may partially have the effect of light protection. However, these substances are unsuitable for transparent plates, as they result in discoloration or color change. Only the organic and organometallic compounds that impart color or zero or extremely light color change to the thermoplastic material to be stabilized are suitable for the transparent amorphous plates. The ultraviolet stabilizers suitable as light stabilizers are, for example, 2-hydroxybenzo-phenones, 2-hydroxybenzotriazoles, organonickel compounds, salicylic esters, cinnamic acid ester derivatives, resorcinol morbenzoates, oxalic acid anilides, hydroxybenzoic esters, sterically hindered amines and triazines, 2-hydroxybenzotriazoles and triazines being preferred . In a particularly preferred embodiment, the amorphous sheet according to the invention contains, as the main constituent, a crystallizable polyethylene naphthalate and 0.01% by weight to 5.0% by weight of 2- (4,6-diphenyl-1,3, 5-triazinn-2-yl) -5- (hexyl) oxy-phenol or 0.001% by weight at 5.0% by weight of 2,2'-methylene-bis (6- (2H-benzotriazol-2-yl) 4- (1, 1,3, 3-tetramethylbutyl) -phenol In a preferred embodiment, mixtures of these two ultraviolet stabilizers or mixtures of at least one of these two ultraviolet stabilizers with other ultraviolet stabilizers can also be used, the total concentration of the light stabilizers preferably between 0.01% by weight and 5.0% by weight, based on the weight of the crystallizable polyethylene naphthalate According to the invention, it is understood that the crystallizable polyalkylene naphthalate means: - naphthalate homopolymers of crystallizable polyalkylene, copolymers of polyalkyl naphthalate crystallizable ene, - crystallizable polyalkylene naphthalate composite materials, - recrystallized crystallizable polyalkylene naphthalate material and - other variations of crystallizable polyalkylene naphthalate. Preferred copolymers and composites in this context are mixtures of polyalkylene naphthalates and polyalkylene terephthalates, in particular mixtures of polyethylene naphthalate (PEN) and polyethylene terephthalate (PET). It is understood that the amorphous sheet in the context of the present invention provides that those plates that are non-crystalline, although the thermoplastic material employed preferably have a crystallinity of between 10% and 65%. Non-crystalline, ie essentially amorphous, means that the degree of crystallinity is generally less than 5%, preferably less than 2% and particularly preferably 0%. In addition, a good cold capacity can be set without fracture, without a size crack being found. of a hair and / or white fracture in a completely unexpected manner so that the sheet according to the invention can be shaped and bent without the action of temperature. Furthermore, measurements have shown that the polyalkylene naphthalate sheet according to the invention has low combustibility and low flammability, so that it is suitable, for example, for interior applications and in display construction. The sheet according to the invention can also be recirculated without problems, without contamination of the environment and without loss of mechanical properties, which means that it is suitable, for example, for use as short-term warning signs and other articles of warning . In a particularly preferred embodiment, the amorphous sheet according to the invention contains, as the main constituent, crystallizable polyethylene naphthalate. In the case of polyethylene naphthalate, preferably no fracture occurs on the sheet during the measurement of the impact strength C arpy an (measured in accordance with ISO 179 / 1D). In addition, the impact resistance of izod aj jarring? (measured according to ISO 180 / 1A) of the sheet is preferably in the range of 2.0 to 12.0 kJ / m 2, particularly preferably in the range of 3. 0 to 8.0 kJ / m2. The polyethylene naphthalates having a melting point of crystallite Tm measured by DSC (differential scanning calorimetry) with a heating rate of 10 ° C / minute, from 240 ° C to 300 ° C, preferably from 250 ° C to 290 ° C ° C, a temperature range of Tc crystallization of 100 ° C and 290 ° C, a glass transition temperature Tg between 100 ° C and 140 ° C and a density, measured in accordance with DIN 53479, of 1.30 a 1.45 g / cm3 and a crystallinity of between 10% and 65% of the preferred polymers as starting materials for the production of the sheet. The typical viscosity SV (DCA) of polyethylene naphthalate, measured in dichloroacetic acid according to DIN 53728, is between 600 and 1400, preferably between 750 and 1250, and particularly preferably between 800 and 1100. The intrinsic viscosity IV (DCA) ) is calculated as follows from the typical viscosity SV (DCA).

IV (DCA) = 6.67 x 10"4 SV (DCA) + 0.118 The bulk density, measured in accordance with DIN 53466, is preferably between 0.75 kg / dm3 and 1.0 kg / dm3 and particularly preferably between 0.80 kg / dm3 and 0.90 kg / dm3. The polydispersity of the polyethylene naphthalate Mw / Mn, measured by means of GPC, is preferably between 1.5 and 4.0 and particularly preferably between 2.0 and 3.5. The production of the amorphous sheet according to the invention can be carried out, for example, by an extrusion process in an extrusion line. Such an extrusion line is shown schematically in Figure 1. It essentially comprises: an extruder 1 as a plasticizing unit, a slot mold 2 as a mold to be configured, - a stacking / satin (3) for polishing as a primer mold, a cooling bed (4) and / or a roller conveyor belt (5) for subsequent cooling, - separation rollers (6), - a saw separation (7), - an edge smoothing device (9) and, if appropriate, - a stacking device (8). The process comprises dyeing the polyalkylene naphthalate, if appropriate, then melting the extruder, if appropriate together with the soluble dye, the dye. and / or the ultraviolet stabilizer, extruding the molten bath through a mold and then priming, polishing and cooling it in the polishing stack, before the sheet is cut to a certain size. The soluble dye, the dye and / or the ultraviolet stabilizer are preferably added by the masterbatch technology. In this case, the soluble dye, the dye and / or the ultraviolet stabilizer are completely dispersed in a solid carrier material. Suitable carrier materials are certain resins, the polyalkylene naphthalate itself, or alternatively other polymers that are sufficiently compatible with the polyalkylene naphthalate. The process for the production of the sheet according to the invention is described in detail below for polyethylene naphthalate (PEN). The PEN is preferably dried, before extrusion, at 160 and up to 180 ° C for 4 to 6 hours. The PEN and, if appropriate, the additive masterbatches are then melted in the extruder. The temperature of the molten bath of PEN is preferably in the range of 250 to 320 ° C, it being possible for the temperature of the molten bath to be established essentially both by the temperature of the extruder and by the residence time of the molten bath in the extruder. The molten bath then exits the extruder through a mold. This mold is preferably a slot mold. The PE? melted by the extruder and formed by the slot mold is prepared with the rollers of the polishing satin, i.e. it is intensively cooled and polished. The rollers of the satin can be arranged, for example, in the form of I, F, L or S. The PE material? it can then be subsequently cooled on a roller conveyor belt, smoothed to edge the edges, cut to length and finally stacked. The thickness of the PEN sheet is determined essentially by the removal, which is placed at the end of the cooling zone, coupled the cooling rollers (polish) to this, in terms of speed, and the transport speed of the extruder on one side and the distance between the rollers on the other hand. Single or doubleworm extruders can be used as an extruder. The slot mold preferably comprises the removable die body, the lips and the restriction bar for flow regulation across the width. For this, the control bar can be bent by tension and with pressure screws. The thickness is determined by adjusting the lips. It is important to ensure that the PEN and the lip have uniform temperature, since otherwise the PEN molten bath flows out to different thicknesses as a result of the different flow paths. The priming mold, that is, the polishing satin, gives the molten bath of PEN the configuration and the dimensions. This is done by freezing at less than the glass transition temperature by cooling and polishing. The configuration should no longer take place in this state, since otherwise defects of the surface can be formed in this cooled state. For this reason, the satin rollers are preferably driven together. The temperature of the satin rollers must be lower than the crystallite melting temperature in order to avoid adhesion of the molten PEN bath. The molten bath of PEN leaves the slot mold with a temperature of 240 to 300 ° C. The first polishing / cooling roller has a temperature between 50 ° C and 80 ° C, depending on the exit and thickness of the sheet. The second roller, a little colder, cools the second surface or another. While the prescribing device freezes the PEN surfaces as smoothly as possible and cools the profile to the extent that it is dimensionally stable, the subsequent cooling device decreases the temperature of the PEN sheet virtually at room temperature. The subsequent cooling can take place on a roller table. The speed of the separation must be precisely coordinated with the speed of the satin rollers in order to avoid defects and variations in thickness. As additional devices, the extrusion line for production of PEN plates can comprise a separating saw as a device for cutting along, the edge smoother, the stacking unit and a control station. The edge or margin smoother is advantageous, since in certain circumstances the thickness of the margin region may be a uniform one. The thickness and visual properties of the sheet are measured at the control station. As a result of the surprisingly large number of excellent properties, the amorphous polyalkylene naphthalate sheet according to the invention is outstandingly suitable for a large number of various uses, for example for interior shelves, for display construction and display articles, as indicators visuals for signs, such as machine and vehicle protective glazing, the lighting sector, in store accessories and the construction of shelves, as advertising items, as menu supports, such as basketball boards, as room dividers and also for external applications, for example as a substitute for glass. This invention is illustrated in more detail below with the aid of the examples of embodiments, without being limited thereto. The measurement of individual properties is carried out here according to the following standards or techniques.

MEASUREMENT METHODS Surface brightness The surface brightness is determined according to DIN 67 530. The reflector value is measured as the optical parameter of the surface of a sheet. In accordance with ASTM-D 523-78 and ISO 2813 standards, the angle of incidence was fixed at 20 °. With the fixed angle of incidence the ray of light hits the flat test surface and is reflected and diffused by it. The incident light rays on the electronic receiver are indicated as a proportional electrical value. The value of the measurement is dimensionless and should be set together with the angle of incidence.

Transmission of light The transmission of light is considered to mean the relation between the total amount of light transmitted and the amount of incident light. The transmission of light is measured in a "Hazeguard plus" measuring instrument in accordance with ASTM 1003.

Turbidity and clarity Turbidity is the percentage of transmitted light that deviates from the incident light beam by an average greater than 2.5 °. Clarity is determined at an angle of less than 2.5 °. Turbidity and clarity are measured using a "Hazeguard plus" measuring instrument in accordance with ASTM 1003. i Whiteness Whiteness is determined with the help of the electric reference photometer "ELREPHO" from Zeiss. Overkochem (Germany), typical light source C, 2 ° for the normal observer. Whiteness is defined as 5 G = RY + 3RX - 3RX r WG = a whiteness, RY, RZ, RX = corresponding reflection factors 10 when using color measurement filter Y, Z and X. The white standard used is a compression molding formed from of barium sulfate (DIN 5033, Part 9).

Surface defects 15 Surface defects are determined visually.

Impact resistance Charpy a ^. This value of agreement with ISO 179/1 D is determined.

Resistance to Izod chipping impact aj The impact resistance of Izod chipping or chill resistance? it is measured in accordance with ISO 180 / 1A.

Density 5 The density is determined in accordance with DIN 53479.

SV (DCA). IV (DCA) The typical viscosity SV (DCA) in chloroacetic acid is measured according to DIN 53726. The intrinsic viscosity (IV) is calculated as follows from the typical viscosity (SV) IV (DCA) = 6.67 x 104 SV (DCA) + 0.118 Thermal properties Thermal properties, such as the crystallite melting point Tm, the crystallization temperature range Tc, the subsequent cooling crystallization temperature TQJ and the transition temperature Tg, are measured by differential scanning calorimetry (DSC). ) at a heating rate of 10 ° C / minute.

Molecular weight, polydispersity. The molecular weights Mw and Mn and the resulting polydispersity Mw / Mn are measured by means of gel permeation chromatography (GPC).

Climate change (both sides). ultraviolet stability. The ultraviolet stability is tested as follows in accordance with the ISO 4892 test specification.

Test apparatus Atlas Ci65 Weather Ometer ISO 4892 test conditions, ie simulated climate change Irradiation time 1000 hours (per side) Irradiation 05 W / m2, 340 nm Temperature 63 ° C Relative atmospheric humidity 50% Xenon lamp indoor filter and external borosilicate Irradiation cycles 102 minutes of ultraviolet light, then 18 minutes of ultraviolet light with water spray of the specimens, then 102 minutes of ultraviolet light again, etc.

Color change The color change of the samples after artificial climate change is measured using a spectrophotometer in accordance with DIN 5033.

The symbols have the following meanings, difL: Difference of brightness + difL: The sample is brighter than the norm -difL: The sample is darker than the norm, difA: Difference in the red-green + difA region: The sample is more red than the norm. -difA: The sample is greener than the norm. difB: Difference in the blue-yellow region. + difB: The sample is more yellow than the norm. -difB: the sample is more blue than the norm, difE: Total color change. difE = * difL2 + difA2 + difB2 The greater the numerical deviation of the norm, the greater the difference in color. The numerical values of < . 0.3 are insignificant and mean that there is no significant color change. • Yellow value The yellow value G is the deviation of the lack of color towards "yellow" and is measured according to DIN 6167. The yellow values G of < 5 are visually imperceptible. In the following examples and comparison examples, the plates are in each case single-layer, opaquely colored plates of different thickness produced in the extrusion line described.

EXAMPLE 1 The polyethylene naphthalate from which the transparent sheet is produced has a typical viscosity SV (DCA) of 5 810, which corresponds to an intrinsic viscosity IV (DCA) of 0.65 dl / g. The moisture content is < 0.2% and the density (DIN 53479) is 1.33 m g / cm3. The crystallinity is 15%, the crystalline melting point according to the DSC measurements being 270 ° C. The polydispersity Mw / Mn of 0 polyethylene naphthalate is 2.14. The glass transition temperature is 119 ° C. Prior to extrusion, the polyethylene naphthalate is dried for 5 hours at 170 ° C in a dryer and then extruded in a single worm extruder at an extrusion temperature of 286 ° C through a flat film mold on a smoothing satin whose walls are arranged in an S-shape and smoothed to give a sheet with a thickness of 2mm. The first satin roll has a temperature of 65 ° C and the subsequent rolls each have a temperature of 58 ° C. The separation rate and the speed of the satin roller are 4.0 m / min. After cooling, the transparent PEN sheet with a thickness of 2 mm is smoothed at the edges using separation saws, cut lengthwise and stacked.

The transparent PEN sheet produced has the following properties profile: thickness 2 mm surface brightness, first side 170 (measurement angle 20 °), second side 165 light transmission 86% clarity 98% turbidity 1.5% surface defects per m2 none (stains, orange peel scale, bubbles, etc.) .) impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0% density 1.31 g / m3 EXAMPLE 2 A transparent sheet is produced analogously to Example 1, using a polyethylene naphthalate with the following properties: SV (DCA) 1100 IV (DCA) 0.85 fl / g density 1.32 g / cm3 crystallinity 24% crystalline melting point Tm 254 ° C polydispersity Mw / Mn 2.02 glass transition temperature 117 ° C The extrusion temperature is 280 ° C. The first satin roller has a temperature of 66 ° C and the subsequent rollers have a temperature of 60 ° C. The separation rate and the roller speed of the satin are 1.9 / min. The transparent PEN sheet produced has the following properties profile: thickness: 6 mm surface brightness, first side: 172 (measurement angle 20 °), second side: 170 light transmission: 88.1% clarity: 99.6% turbidity: 2.6% surface defects per m2: none (stains, scale orange peel, bubbles, etc.) impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0% density 1.32 g / m3.

EXAMPLE 3 A transparent sheet is produced analogously to example 2. The extrusion temperature is 275 ° C. The first satin roller has a temperature of 57 ° C and the subsequent rollers have a temperature of 50 ° C. the separation rate and the roller speed of the satin roller are 1.7 m / min. The PEN sheet produced has the following profile of properties: thickness 10 mm surface brightness, first side 151 (measuring angle 20 °), second side 148 light transmission 86.5% clarity 99.2% turbidity 4.95% surface defects per m2 none (stains, orange peel scale, bubbles, etc.) Impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0.1% density 1.33 * -. EXAMPLE 4 A transparent sheet is produced analogously to Example 2. 70% of polyethylene naphthalate of Example 2 is mixed with 30% of the recirculated material made from this polyethylene naphthalate. The produced PEN sheet has the following profile properties: - thickness: 6 mm - surface brightness, first side: 168 (measurement angle 20 °), second side 166 0 - light transmission 87.3% - clarity 99.4% - turbidity 3.2% - surface defects to see none (spots, scale of 5 orange peel, bubbles, etc.) Impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0% density 1.32 g / m3 EXAMPLE 5 An amorphous, transparently colored sheet with a thickness of 6mm is produced which contains, as main constituents, and polyethylene naphthalate of Example 2 and 2% by weight of soluble dye Soluble red 138, an anthraquinone derivative of BASF (R Thermoplast G). The soluble Solvent Red 128 dye is added in the form of a masterbatch. The masterbatch consists of 20% by weight of the Red Solvent 138 dye and 80% by weight of the polyethylene naphthalate described above. Prior to extrusion, 90% by weight of the polyethylene naphthalate and 10% by weight of the masterbatch are dried for 5 hours at 170 ° C in a dryer and then extruded in a single worm extruder at a temperature of extrusion of 280 ° C through a flat film mold on a smoothing satin whose walls are arranged in an S configuration, and smoothed to give a sheet with a thickness of 6 mm. The first roller of the satin has a temperature of 66 ° C and the subsequent rollers each have a temperature of 60 ° C. The separation rate and the roller speed of the satin roller are 2.9 m / min. After cooling, the transparently colored PEN sheet with a thickness of 6 mm is smoothed at the edges using separation saws, cut lengthwise and stacked. ~ \ The produced PEN sheet has the following properties profile: 0 thickness 6 mm surface brightness, first side 118 (measurement angle 20 °), second side 115 light transmission 28.1% 5 clarity 97.1% turbidity 9.6% defects surface per m2 none (stains, scale of orange peel, bubbles, etc.) 0 impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0% density 1.34 g / m3 5 * EXAMPLE 6 An amorphous sheet of white color, with a thickness of 3mm, which contains, as main constituents, the polyethylene naphthalate of Example 2 of 6% by weight of titanium dioxide. ^ The titanium dioxide is of the rutile type and has been coated with an inorganic coating of I2O3 and with an organic coating of polydimethylsiloxane. The dioxide titanium has a mean particle diameter of 0.2 μm. The titanium dioxide is added in the form of a masterbatch. The masterbatch consists of 30% by weight of the described titanium dioxide and 70% by weight of the described polyethylene naphthalate. Before the extrusion, 80% by weight of polyethylene naphthalate and 20% by weight of the masterbatch of titanium dioxide are dried for 5 hours at 170 ° C in a dryer and then extruded in a worm extruder. single at an extrusion temperature of 286 ° Ca through a flat film mold on a smoothing satin whose walls are arranged in an S-shape and smoothed to give a sheet with a thickness of 3 mm. The first roller of the satin has a temperature of 67 ° C. The separation rate and the speed of the satin rolls is 6.5 m / min.

After cooling, the white PEN sheet with a thickness of 3 mm is smoothed at the edges using separation saws, cut lengthwise and stacked. The white colored sheet produced has the following properties: thickness 3 mm surface brightness, first side 123 (measurement angle 20 °), second side 122 light transmission 0% whiteness 110 white coloration, homogeneous surface defects by tir "none (spots, orange peel scale, bubbles , etc.) impact resistance Charpy an without fracture cold configurability good crystallinity 0% EXAMPLE 7 An amorphous, transparent sheet with a thickness of 3 mm containing, as a main constituent, the polyethylene naphthalate of Example 2 and 1.0% by weight of ultraviolet stabilizer 2- (4,6-diphenyl-1,3,3- triazin-2-yl) -5- (hexyl) oxy-phenol (R Tinuvin 1577 from Ciba-Geigy). Tinuvin 1577 has a melting point of 149 ° C and is thermally stable up to about 330 ° C. In order to achieve a distribution, 1.0% by weight of the ultraviolet stabilizer is incorporated directly to the polyethylene naphthalate by the producer of the starting material. Prior to extrusion, the polyethylene naphthalate is dried for 5 hours at 170 ° C in a dryer and then extruded in a single worm extruder at an extrusion temperature of 286 ° C through a flat film mold on a smoothing satin whose walls are arranged in an S configuration and are smoothed to give a sheet with a thickness of 3 mm. The first roller of the satin has a temperature of 73 ° C, and the subsequent rolls each have a temperature of 67 ° C. The separation rate and the speed of the satin rollers are 6.5 m / min. After cooling, the transparently colored PEN sheet with a thickness of 3mm is smoothed at the edges using separation saws, cut lengthwise and stacked. The transparent sheet produced has the following properties. thickness 3 mm surface brightness, first side 168 (measurement angle 20 °), second side 161 light transmission 85% clarity 97% turbidity 1.8% surface defects per m2 none (stains, orange peel scale, bubbles, etc.) Impact resistance Charpy an without fracture good cold configurability, no defects crystallinity 0% density 1.33 g / cm3 'After climate change for 1000 hours on each side by means of an Atlas Ci 65 Weather Ometer, the PEN sheet has the following properties: thickness 3 mm surface brightness, first side 162 (measurement angle 20 °), second side 153 light transmission 84.1% clarity 96% turbidity 2.0% total discoloration difE 0.22 discoloration dark difL -0.18 discoloration red-green difA -0.08 discoloration blue - yellow difB 0.10 surface defects per m none (stains, scale of orange peel, bubbles, etc.) value yellow G impact resistance Charpy an without fracture cold configurability good

Claims (3)

? NOVELTY OF THE INVENTION CLAIMS

1. An amorphous sheet having a thickness in the range of 1 to 20 mm, containing, as a constituent, at least one polyalkyl naphthalate.

2. - A sheet as claimed in the claim < 1, which contains at least one dye that is soluble in the polyalkyl naphthalate.

3. - A sheet as claimed in claim 1 or 2, which contains at least one organic and / or inorganic pigment as colorant. . - A sheet as claimed in at least one of claims 1 or 3, which contains at least one UV stabilizer as a light stabilizer. 5- A sheet as claimed in at least one of claims 1 to 4, further characterized in that the polyalkylene naphthalate used is polyethylene naphthalate, polypropylene naphthalate and / or polybutylene naphthalate. 6. - A sheet as claimed in at least one of claims 1 to 5, further characterized by the polyalkylene naphthalate. 7. A process for the production of an amorphous sheet 5 as claimed in at least one of claims 1 to 6, which comprises melting the polyalkylene naphthalate in the extruder, extruding the molten bath through a mold and setting it up then, polishing and cooling it with at least two rollers in the polishing stack, before the sheet is cut to the proper size. 8. The process as claimed in claim 7, further characterized in that the polyalkylene naphthalate is fused together with the soluble dye, the dye and / or the UV stabilizer. 9. The process as claimed in claim 7 or 8, further characterized in that the polyalkylene naphthalate is dried before it is melted in the extruder. 10. The method as claimed in at least one of claims 7 to 9, further characterized in that the polyalkylene naphthalate used is polyethylene naphthalate (PEN). 11. - The method as claimed in claim 10, further characterized in that the temperature of the molten bath of PEN is in the range of 250 to 320 ° C. 12. - The method as claimed in claim 10 or 11, further characterized in that the first polishing stacking roll has a temperature that is in the range of 50 to 80 ° C.