Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D7/00—Producing flat articles, e.g. films or sheets
  • B29D7/01—Films or sheets
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
  • B29C43/22—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
  • B29C43/22—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length
  • B29C43/222—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of indefinite length characterised by the shape of the surface
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material

Definitions

• the invention relates to an amorphous, transparent plate made of a crystallizable thermoplastic with a high standard viscosity, the thickness of which is in the range from 1 to 20 mm.
• the plate is characterized by very good optical and mechanical properties.
• the invention further relates to a method for producing this plate and its use.
• thermoplastics that are processed into sheets are, for example, polyvinyl chloride (PVC), polycarbonate (PC) and polymethyl methacrylate (PMMA).
• PVC polyvinyl chloride
• PC polycarbonate
• PMMA polymethyl methacrylate
• the amorphous thermoplastics can be easily reshaped using smoothing units or other shaping tools due to the steadily increasing viscosity as the temperature decreases. After shaping, amorphous thermoplastics then have sufficient stability, ie a high viscosity, to "stand by themselves” in the calibration tool. But they are still soft enough to be shaped by the tool. The melt viscosity and inherent stiffness of amorphous thermoplastics is so high in the calibration tool that the semi-finished product does not collapse in the calibration tool before it cools down. With easily decomposable materials such. B. PVC are special processing aids in extrusion, such as. B. Processing stabilizers against decomposition and lubricants against excessive internal friction and thus uncontrollable heating necessary. External lubricants are required to prevent snagging on walls and rollers. When processing PMMA z. B. used a degassing extruder for dehumidification.
• PMMA sheets also have extremely poor impact strength and shatter when broken or subjected to mechanical stress.
• PMMA panels are highly flammable, so that they cannot be used, for example, for indoor applications or in trade fair construction.
• PMMA and PC sheets are also not cold-formable. During cold forming, PMMA sheets break into dangerous fragments. When cold-forming PC sheets, hairline cracks and whitening occur.
• EP-A-0 471 528 describes a method for molding an article from a polyethylene terephthalate (PET) plate.
• the intrinsic viscosity of the PET used is in the range from 0.5 to 1.2.
• the PET sheet is heat-treated on both sides in a deep-drawing mold in a temperature range between the glass transition temperature and the melting temperature.
• the molded PET sheet is taken out of the mold when the degree of crystallization of the molded PET sheet is in the range of 25 to 50%.
• the PET sheets disclosed in EP-A-0 471 528 have a thickness of 1 to 10 mm.
• the deep-drawn molded article produced from this PET sheet is partially crystalline and therefore no longer transparent, and the surface properties of the molded article through the deep-drawing process, the given temperatures and Forms are determined, it is immaterial which optical properties (e.g. gloss, haze and light transmission) have the PET sheets used. As a rule, the optical properties of these plates are poor and need to be optimized.
• US Pat. No. 3,496,143 describes the vacuum deep drawing of a 3 mm thick PET sheet, the crystallization of which is said to be in the range from 5 to 25%. However, the crystallinity of the deep-drawn molded body is greater than 25%. No demands are made on the optical properties of these PET sheets either. Since the crystallinity of the plates used is already between 5 and 25%, these plates are cloudy and opaque.
• the object of the present invention is to provide an amorphous, transparent plate with a thickness of 1 to 20 mm, which has both good mechanical and optical properties.
• Good optical properties include, for example, high light transmission, high surface gloss, extremely low haze and high image sharpness (clarity).
• the good mechanical properties include high impact strength and high breaking strength.
• the plate according to the invention should be recyclable, in particular without loss of the mechanical properties, and also flame-retardant, so that it can also be used, for example, for interior applications and in trade fair construction.
• DCE standard viscosity SV
• the standard viscosity SV (DCE) of the crystallizable thermoplastic measured in dichloroacetic acid according to DIN 53728 is preferably between 2000 and 5000 and particularly preferably between 2500 and 4000.
• the intrinsic viscosity IV (DCE) is calculated as follows from the standard viscosity SV (DCE):
• the surface gloss measured according to DIN 67530 (measuring angle 20 °), is greater than 120, preferably greater than 130, the light transmission, measured according to ASTM D 1003, is more than 84%, preferably more than 86%, and the turbidity of the plate, measured according to ASTM D 1003, is less than 15%, preferably less than 11%.
• the main component of the transparent, amorphous plate is a crystallizable thermoplastic.
• Suitable crystallizable or semi-crystalline thermomers are, for example, polyethylene terephthalate,
• crystallizable thermoplastic is understood to mean crystallizable homopolymers, crystallizable copolymers, crystallizable compounds, crystallizable recyclate and other variations of crystallizable thermoplastics.
• amorphous plate is understood to mean plates which, although the crystallizable thermoplastic used preferably has a crystallinity of between 5 and 65%, are not crystalline.
• polyethylene terephthalates usually takes place by polycondensation in the melt or by a two-stage polycondensation, the first step up to an average molecular weight - corresponding to an average intrinsic viscosity IV of about 0.5 to 0.7 - in the melt and the further condensation is carried out by solid condensation.
• the polycondensation is generally in the presence of known polycondensation or
• PET chips are heated to temperatures in the range from 180 to 320 ° C. under reduced pressure or under protective gas until the desired molecular weight is reached.
• polyethylene terephthalate is described in detail in a variety of patents, e.g. in JP-A-60-139 717, DE-C-2 429 087, DE-A-27 07 491, DE-A-23 19 089, DE-A-1 6 94 461, JP-63-41 528 , JP-62-39 621, DE-A-41 17 825, DE-A-42 26 737, JP-60-141 71 5, DE-A-27 21 501 and US-A-5,296,586.
• Polyethylene terephthalates with particularly high molecular weights can be added by polycondensation of dicarboxylic acid diol precondensates (oligomers) elevated temperature in a liquid heat transfer medium in the presence of conventional polycondensation catalysts and possibly co-condensable modifiers, if the liquid heat transfer medium is inert and free from aromatic components and has a boiling point in the range from 200 to 320 ° C, the weight ratio of the dicarboxylic acid diol precondensate used (Oligomers) to liquid heat transfer medium is in the range from 20:80 to 80:20, and the polycondensation is carried out in the boiling reaction mixture in the presence of a dispersion stabilizer.
• the notched impact strength a k according to Izod (measured according to ISO 180 / 1A) of the plate is preferably in the range from 2.0 to 8.0 kJ / m 2 , particularly preferably in the range from 4.0 to 6.0 kJ / m 2nd
• the image sharpness of the plate which is also called Clarity and is determined at an angle of less than 2.5 ° (ASTM D 1003), is preferably above 96% and particularly preferably above 97%.
• Polyethylene terephthalate polymers with a crystallite melting point T m measured with DSC (differential scanning calorimetry) with a heating rate of 10 ° C / min, from 220 ° C to 280 ° C, in particular 220 ° C to 260 ° C and preferably from 230 ° C to 250 ° C, with a crystallization temperature range T c between 75 ° C and 280 ° C, preferably 75 ° C and 260 ° C, a glass transition temperature T g between 65 ° C and
• the bulk density measured according to DIN 53466, is preferably between 0.75 kg / dm 3 and 1.0 kg / dm, and particularly preferably between 0.80 kg / dm 3 and 0.90 kg / dm 3 .
• the polydispersity of the polyethylene terephthalate M w / M n measured by GPC is usually between 1.5 and 6, preferably between 2.5 and 6.0 and particularly preferably between 3.0 and 5.0.
• the plate according to the invention is equipped with a UV stabilizer as a light stabilizer.
• the concentration of the light stabilizer is preferably in the range from 0.01 to 5% by weight, based on the weight of the crystallizable thermoplastic.
• Light especially the ultraviolet portion of solar radiation, i.e. H. the wavelength range from 280 to 400 nm initiates degradation processes in thermoplastics, as a result of which not only the visual appearance changes as a result of color change or yellowing, but also the mechanical-physical properties are adversely affected.
• Polyethylene terephthalates for example, begin to absorb UV light below 360 nm, their absorption increases considerably below 320 nm and is very pronounced below 300 nm. The maximum absorption is between 280 and 300 nm.
• UV stabilizers or UV absorbers as light stabilizers are chemical compounds that can intervene in the physical and chemical processes of light-induced degradation. Soot and other pigments can partially protect against light. However, these substances are unsuitable for transparent plates because they lead to discoloration or color change. For transparent, amorphous plates, only organic and organometallic compounds are suitable, which give the thermoplastic to be stabilized no or only an extremely small color or color change.
• Suitable light stabilizers or UV stabilizers are, for example
• the transparent, amorphous plate according to the invention contains, as the main constituent, a crystallizable polyethylene terephthalate and 0.01% by weight to 5.0% by weight of 2- (4,6-diphenyl-1,3,5-triazine) -2-yl) -5- (hexyl) oxy-phenol (structure in Fig. 1 a) or 0.01 wt% to 5.0 wt% 2,2'-methylene-bis (6- ( 2H-benzotriazol-2-yl) -4- (1, 1, 3,3-tetramethylbutyl) phenol (structure in Fig. 1 b).
• UV-stabilized plates according to the invention have no or only slight yellowing, embrittlement, loss of gloss on the surface, cracking on the surface and deterioration of the mechanical properties even after 5 to 7 years of outdoor use.
• the plate according to the invention is flame-retardant and flame-retardant, so that it is suitable, for example, for indoor applications and in trade fair construction.
• the plate according to the invention can be easily recycled without environmental pollution and without loss of mechanical properties, which makes it suitable, for example, for use as short-lived advertising signs or other promotional items.
• the panel has improved weathering resistance and increased UV stability.
• the transparent, amorphous plate according to the invention can be produced, for example, by an extrusion process in an extrusion line. Such an extrusion line is shown schematically in FIG. 2.
• It essentially comprises an extruder (1) as a plasticizing system, a slot die (2) as a tool for shaping, a smoothing unit / calender (3) as a calibration tool, a cooling bed (4) and / or a roller conveyor (5) for after-cooling, a roller take-off (6), a separating saw (7), a side cutting device (9), and optionally a stacking device (8).
• the process is characterized in that the crystallizable thermoplastic is dried, if necessary, then melted together with the UV stabilizer in the extruder, the melt is shaped through a nozzle and then calibrated, smoothed and cooled in the calender before the plate is brought to size.
• the polyethylene terephthalate is preferably dried at 160 to 180 ° C. for 4 to 6 hours before extrusion.
• the polyethylene terephthalate is then melted in the extruder.
• the temperature of the PET melt is preferably in the range from 250 to 320 ° C., the temperature of the melt being able to be set essentially both by the temperature of the extruder and by the residence time of the melt in the extruder.
• a light stabilizer is used, this can already be metered in at the raw material manufacturer or metered into the extruder during plate manufacture.
• the addition of the light stabilizer via masterbatch technology is particularly preferred.
• the light stabilizer is fully dispersed in a solid carrier material. Suitable carrier materials are certain resins, the crystallizable thermoplastic itself, for example polyethylene terephthalate, or other polymers which are sufficiently compatible with the crystallizable thermoplastic.
• the grain size and the bulk density of the masterbatch are similar to the grain size and the bulk density of the crystallizable thermoplastic, so that a homogeneous distribution and thus a homogeneous UV stabilization can take place.
• the melt then leaves the extruder through a nozzle.
• This nozzle is preferably a slot die.
• the PET melted by the extruder and shaped by a slot die is calibrated by smoothing calender rolls, i.e. H. intensely chilled and smoothed.
• the calender rolls can, for example, be arranged in an I, F, L or S shape (FIG. 3).
• the PET material can then be cooled on a roller conveyor, cut to the side, cut to length and finally stacked.
• the thickness of the PET plate is essentially determined by the take-off, which is arranged at the end of the cooling zone, the cooling (smoothing) rolls coupled with it in terms of speed and the conveying speed of the extruder on the one hand and the distance between the rolls on the other hand.
• Both single-screw and twin-screw extruders can be used as extruders.
• the slot die preferably consists of the separable tool body, the lips and the dust bar for flow regulation across the width.
• the dust bar can be bent by tension and pressure screws.
• the thickness is adjusted by adjusting the lips. It is important to ensure that the temperature of the PET and the lip is even, otherwise the PET melt will flow out to different thicknesses due to the different flow paths.
• the calibration tool, d. H. the smoothing calender gives the PET melt the shape and dimensions. This is done by freezing below the glass transition temperature by cooling and smoothing. Deformation should no longer occur in this state, since otherwise surface defects would occur in this cooled state. For this reason, the calender rolls are preferably driven together. The temperature of the calender rolls must be lower than the crystallite melting temperature in order to avoid sticking of the PET melt. The PET melt leaves the slot die at a temperature of 240 to 300 ° C.
• the first smoothing-cooling roller has a temperature between 50 ° C and 80 ° C depending on the output and plate thickness.
• the second, somewhat cooler roller cools the second or other surface.
• the temperature of the first smoothing cooling roll is in the range from 50 to 80 ° C.
• Freezing brings and cools the profile so far that it is dimensionally stable, lowers the
• After-cooling can be done on a roller board.
• the speed of the trigger should match the speed of the
• Calender rolls must be precisely coordinated to avoid defects and thickness fluctuations.
• a separating saw as a cutting device, the side trimming, the stacking system and a control point can be located in the extrusion line for the production of the plates as additional devices.
• the side or edge trimming is advantageous because the thickness in the edge area can be uneven under certain circumstances. The thickness and appearance of the plate are measured at the control point.
• the transparent and amorphous plate according to the invention is excellently suitable for a variety of different uses, for example for interior cladding, for trade fair construction and trade fair items, as displays, for signs, in the lighting sector, in shop and shelf construction, as promotional items, as Menu card stands, as basketball goal boards, as room dividers, as aquariums, as information boards, as brochure and newspaper stands.
• the plate according to the invention is also suitable for outdoor applications, such as Greenhouses, roofing, external cladding, covers, for applications in the construction sector, illuminated advertising profiles, balcony cladding and roof hatches.
• the surface gloss is measured at a measuring angle of 20 ° according to DIN 67530.
• the reflector value is measured as an optical parameter for the surface of a plate. Based on the standards ASTM-D 523-78 and ISO 2813, the angle of incidence was set at 20 °. A light beam hits the flat test surface at the set angle of incidence and is reflected or scattered by it. The light rays striking the photoelectronic receiver are displayed as a proportional electrical quantity.
• the measured value is dimensionless and must be specified together with the angle of incidence.
• the light transmission is measured with the "Hazegard plus" measuring device in accordance with ASTM D 1003.
• Haze is the percentage of the transmitted light that deviates by more than 2.5 ° on average from the incident light beam.
• the image sharpness is determined at an angle of less than 2.5 °.
• the haze and clarity are measured using the "Hazegard plus" measuring device in accordance with ASTM D 1003.
• the surface defects are determined visually.
• the impact strength or strength a k according to Izod is measured according to ISO 180/1 A.
• the density is determined according to DIN 53479.
• the standard viscosity SV (DCE) is based on DIN 53728 in
• the intrinsic viscosity (IV) is calculated as follows from the standard viscosity (SV)
• the thermal properties such as crystallite melting point T m , crystallization temperature range T c , post- (cold) crystallization temperature T CN and glass transition temperature T g are measured by differential scanning calorimetry (DSC) at a heating rate of 10 ° C / min.
• the molecular weights M w and M n and the resulting polydispersity M ⁇ / M,. are measured by means of gel permeation chromatography (GPC).
• UV stability is tested according to the test specification ISO 4892 as follows
• Test device Atlas Ci 65 Weather Ometer
• Xenon lamp inner and outer filter made of borosilicate
• the color change of the samples after artificial weathering is measured with a spectrophotometer according to DIN 5033.
• the yellowness index G is the deviation from the colorlessness in the "yellow” direction and is measured in accordance with DIN 61 67. Yellow value G values of ⁇ 5 are not visually visible.
• the polyethylene terephthalate from which the transparent plate is made has a standard viscosity SV (DCE) of 3490, which corresponds to an intrinsic viscosity IV (DCE) of 2.45 dl / g.
• the moisture content is ⁇ 0.2% and the density (DIN 53479) is 1.35 g / cm 3 .
• the crystallinity is 19%, the crystallite melting point according to DSC measurements being 243 ° C.
• the crystallization temperature range T c is between 82 ° C and 243 ° C.
• the polydispersity M w / M n of the polyethylene terephthalate is 4.3, where M w is 225070 g / mol and M n is 52400 g / mol.
• the glass transition temperature is 82 ° C.
• the polyethylene terephthalate is dried in a dryer at 170 ° C. for 5 hours and then extruded in a single-screw extruder at an extrusion temperature of 292 ° C. through a slot die onto a smoothing calender, the rollers of which are arranged in an S-shape, and extruded to a thickness of 3 mm Smoothed plate.
• the first calender roll has a temperature of 73 ° C and the subsequent rolls each have a temperature of 67 ° C.
• the speed of the take-off and the calender rolls is 6.5 m / min.
• the transparent, 3 mm thick PET sheet is trimmed at the edges with separating saws, cut to length and stacked.
• the transparent PET sheet produced has the following property profile:
• Polyethylene terephthalate which has the following properties:
• the extrusion temperature is 280 ° C.
• the first calender roll has a temperature of 66 ° C and the subsequent rolls have a temperature of 60 ° C.
• the speed of the take-off and the calender rolls is 2.9 m / min.
• the transparent PET sheet produced has the following property profile:
• Extrusion temperature is 275 ° C.
• the first calender roll has one
• the PET sheet produced has the following property profile:
• Thickness 10 mm
• Notched impact strength a k according to Izod 5.0 kJ / m 2
• Polyethylene terephthalate which has the following properties:
• the extrusion temperature is 274 ° C.
• the first calender roll has a temperature of 50 ° C and the subsequent rolls have a temperature of 45 ° C.
• the speed of the take-off and the calender rolls is 1.2 m / min.
• the transparent PET sheet produced has the following property profile:
• Example 2 Analogous to example 2, a transparent plate is produced. 70% polyethylene terephthalate from Example 2 are mixed with 30% recyclate from this polyethylene terephthalate.
• the transparent PET sheet produced has the following property profile:
• Example 2 Analogously to Example 1, a 3 mm thick, transparent, amorphous plate is produced, the main constituent of which is the polyethylene terephthalate from Examples 1 and 1,
• UV stabilizer 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxyphenol ®
• Tinuvin 1577 has a melting point of 149 ° C and is thermally stable up to approx. 330 ° C.
• UV stabilizer 1.0% by weight of the UV stabilizer is incorporated directly into the raw material manufacturer
• Example 1 The drying, extrusion and process parameters are chosen as in Example 1.
• the transparent PET sheet produced has the following property profile:
• the PET plate After 1000 hours of weathering per side with the Atlas Ci 65 Weather Ometer, the PET plate shows the following properties: - Thickness 3 mm
• Example 6 Analogously to Example 6, a 3 mm thick, transparent, amorphous plate is produced.
• the UV stabilizer 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) -oxyphenol® (Tinuvin 1 577) is metered in in the form of a masterbatch.
• the master batch ® is composed of 5% by weight of Tinuvin 1577 as the active ingredient and 95% by weight of the polyethylene terephthalate from Example 1.
• Example 1 Before the extrusion, 80% by weight of the polyethylene terephthalate from Example 1 and 20% by weight of the masterbatch are dried at 170 ° C. for 5 hours. The extrusion and sheet production take place analogously to Example 1.
• the transparent, amorphous PET sheet produced has the following property profile:
• the PET plate After 1000 hours of weathering per side with the Atlas Ci 65 Weather Ometer, the PET plate shows the following properties:
• Example 2 Analogously to Example 2, a 6 mm thick, transparent, amorphous plate is produced, which as the main constituent is the polyethylene terephthalate described in Example 2 and 0.6% by weight of the UV stabilizer 2,2'-methylene-bis (6- (2H- benzotriazol-2-yl) -4-
• Tinuvin 360 has a melting point of 1 95 ° C and is thermally stable up to approx. 250 ° C.
• Example 6 0.6% by weight of the UV stabilizer is incorporated directly into the polyethylene terephthalate at the raw material manufacturer.
• the extrusion temperature is 280 ° C.
• the first calender roll has a temperature of 66 ° C and the subsequent rolls have a temperature of 60 C C.
• the speed of the draw-off and of the calender rolls is 2.9 m / min.
• the transparent PET sheet produced has the following property profile:
• the PET plate After 1000 hours of weathering per side with the Atlas Ci 65 Weather Ometer, the PET plate shows the following properties:
• Example 8 Analogously to Example 8, a transparent, amorphous plate is produced.
• the extrusion temperature is 275 ° C.
• the first calender roll has a temperature of 57 ° C and the subsequent rolls have a temperature of 50 ° C.
• the speed of the take-off and the calender rolls is 1.7 m / min.
• the plate is stabilized as described in Example 3.
• the PET sheet produced has the following property profile:
• the PET plate After 1000 hours of weathering per side with the Atlas Ci 65 Weather Ometer, the PET plate shows the following properties: Thickness 10 mm
• a transparent plate is produced.
• the polyethylene terephthalate used has a standard viscosity SV (DCE) of 760, which corresponds to an intrinsic viscosity IV (DCE) of 0.62 dl / g.
• DCE intrinsic viscosity IV
• the other properties are identical to the properties of the polyethylene terephthalate from Example 1 within the scope of the measurement accuracy.
• the process parameters and the temperature were chosen as in Example 1. Due to the low viscosity, plate production is not possible. The melt stability is insufficient, so that the melt collapses on the calender rolls before cooling.
• a transparent plate is produced analogously to Example 2, the polyethylene terephthalate from Example 2 also being used.
• the first calender roll has a temperature of 98 ° C and the subsequent rolls each have one Temperature of 92 ° C.
• the plate produced is extremely cloudy.
• the light transmission, the clarity and the gloss are significantly reduced.
• the plate shows surface defects and structures.
• the optics are unacceptable for a transparent application.
• the plate produced has the following property profile:

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• 1995
  • 1995-08-02 DE DE19528336A patent/DE19528336A1/de not_active Withdrawn
• 1996
  • 1996-07-15 KR KR1019980700689A patent/KR19990036024A/ko not_active Application Discontinuation
  • 1996-07-15 PL PL96324868A patent/PL324868A1/xx unknown
  • 1996-07-15 CN CN96197028A patent/CN1196698A/zh active Pending
  • 1996-07-15 WO PCT/EP1996/003089 patent/WO1997004948A1/de not_active Application Discontinuation
  • 1996-07-15 EP EP96927002A patent/EP0842039A1/de not_active Withdrawn
  • 1996-07-15 CA CA002228364A patent/CA2228364A1/en not_active Abandoned
  • 1996-07-15 HU HU9802435A patent/HUP9802435A2/hu unknown
  • 1996-07-15 AU AU66990/96A patent/AU6699096A/en not_active Abandoned
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  • 1996-07-15 JP JP9507164A patent/JPH11510112A/ja active Pending
  • 1996-07-15 BR BR9610186A patent/BR9610186A/pt not_active Application Discontinuation
  • 1996-07-30 TW TW085109483A patent/TW355718B/zh active
• 1998
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  • 1998-01-29 NO NO980393A patent/NO980393L/no unknown
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