Classifications

• • 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
  • B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
  • B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
  • B29C59/04—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing using rollers or endless belts
• • 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
  • B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
  • B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
  • B29C59/04—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing using rollers or endless belts
  • B29C59/046—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing using rollers or endless belts for layered or coated substantially flat surfaces
• • 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
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
  • B29C48/07—Flat, e.g. panels
  • B29C48/08—Flat, e.g. panels flexible, e.g. films
• • 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
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
• • 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
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
  • B29C48/18—Articles comprising two or more components, e.g. co-extruded layers the components being layers
  • B29C48/21—Articles comprising two or more components, e.g. co-extruded layers the components being layers the layers being joined at their surfaces
• • 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
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
  • B29C48/91—Heating, e.g. for cross linking
• • 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
  • B29D11/00—Producing optical elements, e.g. lenses or prisms
• • 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
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/25—Component parts, details or accessories; Auxiliary operations
  • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
  • B29C48/911—Cooling
  • B29C48/9135—Cooling of flat articles, e.g. using specially adapted supporting means
  • B29C48/914—Cooling of flat articles, e.g. using specially adapted supporting means cooling drums
• • 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
  • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
  • B29K2023/04—Polymers of ethylene
  • B29K2023/06—PE, i.e. polyethylene
  • B29K2023/0608—PE, i.e. polyethylene characterised by its density
  • B29K2023/0633—LDPE, i.e. low density polyethylene
• • 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
  • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
  • B29K2023/04—Polymers of ethylene
  • B29K2023/06—PE, i.e. polyethylene
  • B29K2023/0608—PE, i.e. polyethylene characterised by its density
  • B29K2023/065—HDPE, i.e. high density polyethylene
• • 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
  • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
  • B29K2023/10—Polymers of propylene
  • B29K2023/12—PP, i.e. polypropylene
• • 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
  • B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
  • B29K2027/06—PVC, i.e. polyvinylchloride
• • 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
  • B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
  • B29K2033/04—Polymers of esters
  • B29K2033/12—Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
• • 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
• • 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
  • B29K2069/00—Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• • 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
  • B29K2077/00—Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• • 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
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/25—Solid
  • B29K2105/253—Preform
  • B29K2105/256—Sheets, plates, blanks or films
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2011/00—Optical elements, e.g. lenses, prisms

Definitions

• the invention relates to a co-extruded plastic film with a prism structure, a process for the production of co-extruded plastic films with prism structure and their uses.
• thermoplastics structuring of the surface is preferably achieved by the action of a stamping tool on the surface located in the corresponding temperature state.
• a stamping tool on the surface located in the corresponding temperature state.
• PMMA-based plastic sheet material with characteristically textured surfaces are u.a. produced by extrusion with simultaneous embossing in a three-roll calender (calender). In this case, a roller (embossing roll) is provided with the negative of the desired plate structure.
• the goal with structured plates is to give the best possible picture of the roll structure. This goal is achieved by setting the lowest possible melt viscosity and the highest possible roller temperature. Furthermore, as practice shows, the maximum pressure in front of the narrowest point in the nip (i.e., the gap between smooth and textured roll) should be high in order to transfer as much embossing force as possible. The three conditions mentioned inevitably result in compromises in the technical implementation of the extrusion of structured sheets.
• the roller temperature can not be increased arbitrarily, since most plastic melts stick to hot metals. From a certain roll temperature, this sticking tendency leads to separation difficulties on the embossing roll.
• the melt viscosity of the plastic can not be chosen arbitrarily low, such as by setting high melt temperatures, otherwise the stamping force in the nip is too low.
• Another object was to provide thin films with a textured surface.
• the task was also to provide an economical, continuous process.
• the object was achieved by a continuous process for the production of coextruded plastic films with a prismatic structure, characterized in that in the extrusion process, a base film having a thickness between 0.10 and 0.35 mm and a low-viscosity layer coextruded and then by means of a heatable roll calender, containing a roller with a structuring surface, the film composite is provided with a structuring.
• a coextruded plastic film is produced by means of an extrusion line equipped with 2 extruders and a roll calender comprising a roller with a structured surface (embossing roll), a low-viscosity layer being applied to a high-viscosity base film.
• the coextruded plastic film is then structured in the roll calender by the embossing roll.
• embossing roll By using a high-viscosity base film, the introduction of the necessary embossing force is ensured.
• Both base film and coextrusion layer are preferably thermoplastics.
• Suitable thermoplastics include polyacrylates, in particular PMMA, polycarbonate, polyolefins, LDPE, HDPE, PP, polyethylene terephthalate, PVC, polystyrene, polyamide.
• the low-viscosity coextrusion layer can advantageously consist of the same types of plastic as the base film, but it can also consist of a sufficiently compatible with this plastic. (See JE Johnson, Kunststoff Scheme K), 538-541 (1976)).
• the melt viscosity of the coextrusion material should be that of an injection molding compound for high imaging accuracy.
• Polycarbonate is particularly preferred since the refractive index of 1.58 is well suited for optical applications. For example, polycarbonate ensures efficient light control.
• the coextruded layer is preferably made of a low viscosity material.
• flow improvers may also be added to the material.
• low molecular weight compounds are suitable, such as low molecular weight polymethylmethacrylate.
• the MVR (melt yolumeflow rate) ratio between high-viscosity base film and low-viscosity coextrusion layer is ideally between 1:20 and 1: 8, preferably 1:10.
• the thickness of the low-viscosity coextrusion layer depends on the function.
• the embossing of a structure requires precisely coordinated process parameters. The possibilities of adaptation are limited: The roller temperature can not be increased arbitrarily, since most plastic melts stick to hot metals. From a certain roll temperature, this sticking tendency leads to separation difficulties on the embossing roll.
• the melt viscosity of the plastic can not be arbitrarily low be selected, for example by setting high melt temperatures, otherwise the embossing force in the nip is too low.
• the layer thickness of the coextrusion layer has a special influence.
• the layer thickness should have at least a quarter of the structure height of the embossing roll.
• release agents With an optimal adaptation of the process parameters can be dispensed with the use of release agents. Nevertheless, if the use of release agents in the coextrusion layer is required, those skilled in the art are familiar with the materials known from the prior art (HF Mark et al., Encyclopedia of Polymer Science & Engineering, Index Volume pg., 307-324, J. Wiley 1990 Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed. Vol. A20, pg. 479-483, VCH 1992, R. Gaechter, H. Müller Kunststoffadditive, 3rd ed. Carl Hanser Verlag 1989).
• the content of the release agent used with the coextrusion layer is preferably in the range from 0 to 0.34% by weight, based on the mass of coextrudate. Particular mention may be made of higher alcohols.
• the use of a release agent in the coextrusion compound reduces the tendency of the melt to adhere to hot metal.
• the embossing roll temperature can therefore be increased considerably in the embossing process.
• up to 70 ° C. above the glass transition temperature Tg of the coextrusion compound may be mentioned.
• the glass transition temperatures Tg are known or can be calculated or determined. (See Brandrup-Immergut, Polymer Handbook, Chapter V, J. Wiley, Vieweg-Esser, Kunststoff-Handbuch Vol. IX, 333-340, Carl Hanser 1975 ).
• the process according to the invention can be carried out as follows:
• the extrusion plant is essentially composed of a main extruder, a coextruder and a coextrusion tool.
• the maximum width of the extruded films is determined by the coextrusion tool. In general, the extruded films are 400 to 2000 mm wide. Their thickness is also limited by the conditions of coextrusion; In general, the thickness of the base film is 0.10 to 0.35 mm, wherein the layer formed from the low-viscosity material is determined primarily by the function intended with the structuring. In general, however, their layer thickness is 0.006 to 0.075 mm.
• the structure depth of the embossing roll is ideally between 0.025 and 0.070 mm.
• the base molding compound brought to a suitable temperature by the main extruder and the low-viscosity molding compound brought to a suitable temperature in the coextruder are combined in the coextrusion die.
• the coextrudate exiting the coextrusion die is passed over the roll calender, with a roll designed as an embossing roll so that its surface is the negative of the desired textured film surface. Between the pressure roller and the embossing roller is the nip. Here, the maximum pressure before the narrowest point should be high in order to transfer as much embossing force.
• the roller calender corresponds otherwise in the prior art.
• the extruded foils with a textured surface are transported via support rollers. Then they can be wound to the desired length and / or cut. The profile then represents an exact image of the embossing roll surface.
• the MVR ratio of the base film to the coextruded layer is between 1:20 and 1: 8, preferably 1:10.
• the coextruded layer may have a thickness of at least half the structural height. Contrary to DE 4407468, the thickness of the coextruded layer can be greater than the structure depth of the embossing roll.
• One field of application for the films produced according to the invention are optical materials. Since a high-quality material is required for optical applications, this process is preferably carried out in a clean room. For the particularly interesting application as a film for the display backlighting is working in the clean room class 100, since the dust load of the ambient air would lead to unacceptable contamination of the film.
• polycarbonate having an MVR of 6 is coextruded with a low viscosity polycarbonate having an MVR of 66.
• the base film has a width of 1800 mm and a thickness of 150 .mu.m, the coextruded layer has a thickness of 25 .mu.m.
• the coextrudate is passed through a heatable roll calender, here a three-roll calender, which has an embossing roll with prismatic structure.
• the structure depth of the embossing roller is 50 ⁇ m.
• the embossing roller is heated to about 200 0 C.
• the coextruded film is passed over the embossing roller.
• polycarbonate having an MVR of 6 is coextruded with a low viscosity polycarbonate having an MVR of 66.
• the base film has a width of 400 mm and a thickness of 500 .mu.m, the coextruded layer has a thickness of 70 .mu.m.
• the coextrudate is passed through a heatable roll calender, here a three-roll calender, which has an embossing roll with prismatic structure.
• the structure depth of the embossing roller is 50 ⁇ m.
• the embossing roll is set to approx. Heated to 200 ° C.
• the coextruded film is passed over the embossing roller.
• polycarbonate having an MVR of 3 is coextruded with a low viscosity polycarbonate having an MVR of 60.
• the base film has a width of 400 mm and a thickness of 500 .mu.m, the coextruded layer has a thickness of 70 .mu.m.
• the coextrudate is passed over a heatable three-roll calender having an embossing roller with a prismatic structure. The structure depth of the embossing roller is 50 ⁇ m.
• the embossing roller is heated to about 200 0 C. At a speed of 2 m / min, the coextruded film is passed over the embossing roller.
• polymethyl methacrylate having an MVR of 1.2 is coextruded with a low viscosity polymethyl methacrylate having an MVR of 12.
• the base film has a width of 400 mm and a thickness of 800m, the coextruded layer has a thickness of 25 ⁇ m.
• the coextrudate is over heatable three-roll calender led, which has an embossing roller with prismatic structure.
• the structure depth of the embossing roller is 100 ⁇ m.
• the embossing roller is heated to about 180 0 C. At a speed of 2 m / min, the coextruded film is passed over the embossing roller.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Health & Medical Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Ophthalmology & Optometry (AREA)
• Extrusion Moulding Of Plastics Or The Like (AREA)
• Laminated Bodies (AREA)
• Optical Elements Other Than Lenses (AREA)
• Polarising Elements (AREA)

Applications Claiming Priority (2)

Publications (1)

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• 2005
  • 2005-12-16 DE DE102005060731A patent/DE102005060731A1/de not_active Withdrawn
• 2006
  • 2006-10-02 AU AU2006328835A patent/AU2006328835A1/en not_active Abandoned
  • 2006-10-02 CA CA002629595A patent/CA2629595A1/en not_active Abandoned
  • 2006-10-02 CN CNA2006800440433A patent/CN101331012A/zh active Pending
  • 2006-10-02 JP JP2008544902A patent/JP2009519145A/ja active Pending
  • 2006-10-02 US US12/091,174 patent/US20080224339A1/en not_active Abandoned
  • 2006-10-02 WO PCT/EP2006/066963 patent/WO2007071467A1/de active Application Filing
  • 2006-10-02 BR BRPI0619995-0A patent/BRPI0619995A2/pt not_active IP Right Cessation
  • 2006-10-02 KR KR1020087014316A patent/KR20080077185A/ko not_active Application Discontinuation
  • 2006-10-02 EP EP06806924A patent/EP1960181A1/de not_active Withdrawn
  • 2006-10-02 RU RU2008128559/12A patent/RU2008128559A/ru unknown
  • 2006-12-12 TW TW095146425A patent/TW200738440A/zh unknown
• 2008
  • 2008-05-20 ZA ZA200804343A patent/ZA200804343B/xx unknown

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