CZ20002065A3 - Method for producing surface-hardened film which is highly glossy on both sides, free of gel bodies and can be manipulated in the "film-insert-moulding" method - Google Patents

Abstract

In the production method, surface hardened, high on both sides a shiny foil that is practically free of gel particles, p with a thickness of 80 to 300 µm, the melt, e.g. polymethyl methacrylate is produced by the extruder a it is supplied to the smoothing nozzle by means of a flexible lamella nozzle a rolling stand which is arranged for particularly large the thrust forces in the rolling slit, the screed rollers being crowned. Foils are used for surface decoration high quality thermoplastic molded parts.

Description

Technical field

When injection molded parts are decorated with printed polymethacrylate (PMMA) films, they are used to produce a certain "depth effect" of printing a PMMA film with a thickness of 80 to 300 µm. For decoration, either the printed PMMA foils co-laminated with the thermoplastic carrier materials are preformed and embossed on the desired geometry, fed to the injection molding machine and sprayed, or the printed PMMA foil in the form of a roll is fed into the injection molding machine and sprayed. The spraying is carried out on the printed side, so that the printing is protected by a PMMA film containing a UV absorbing substance. The following thermoplastics and polymer blends can be used for injection molding: ABS, PC / ABS blends, PVC, PC, PC / ASA blends, PP, PP blends.

For decoration, either the printed foil moldings (optionally preformed) are inserted into the injection molding machine and sprayed, or the printed PMMA film from the roll is introduced into the injection molding tool and sprayed, or the PMMA film is laminated to a thermoplastic carrier material and (optionally preformed) is introduced into an injection molding machine and sprayed. For example, the following thermoplastics can be used as carrier materials that are laminated with the printed film of the invention: ABS, polycarbonate-ABS blends, ASA (acryloester-styrene-acrylonitrile copolymer), polycarbonate-ASA blends, polyolefin-containing blends such as polyethylene , polypropylene, PVC, and mixtures containing polyphenylene. All thermoplastic materials can be glass fiber reinforced

-2or mineral fillers.

The PMMA foil takes over the function of a protective varnish. Unlike injection molded parts, protected lacquer or printed directly or indirectly (heat transfer, wet transfer), surface decoration with printed PMMA films offers the following advantages:

- Significant cost reductions (surface finishing and decoration in one step)

- solvent-free process

- low investment and environmental costs

- easy replacement of the printed pattern

- greater freedom of choice of pattern.

Decorating thermoplastic moldings with printed films as part of the injection molding process is commonly referred to as "in-mold-film-decoration". The best-known form of this method is so-called "Insert-Molding". For this purpose, the decor-printed PMMA foil for reinforcement is co-laminated with the thermoplastic carrier material. ABS, ASA, PC, PVC, PP, PPE and mixtures of these materials are preferably used for this purpose.

The film laminate is shaped and stamped into the desired geometry by means of a thermal forming process. The preforms are then fed to the injection molding process for the actual production of the moldings. For this purpose, the preforms, usually automatically, are introduced into an injection molding machine and sprayed with thermoplastic plastics. ABS, ASA, PC, PVC, PP, PPE as well as mixtures of these materials are preferably used for spraying. If sufficient support material is used

-3 • tt thickness, it is possible to save spraying and directly use preformed, punched or cut laminate.

“In-Mold-Film-Decoration offers processors and processors a very rational process and fast pattern change capability. mold manufacturers the possibility of replacing the traditional costly method.

The PMMA film, printed with transparent, elastic lacquers, sprayed with a transparent thermoplastic, can be used, for example, in a rational manner for the production of automobile taillight covers. PMMA molding compositions, SAN, polystyrene molding compositions, polycarbonates as well as PMMA / SAN mixtures are preferably used as transparent thermoplastics.

This method offers the possibility of rapid pattern change without the need to build new, expensive multi-component injection molding machines. In addition, expensive dyeing of PMMA molding compositions for multi-component injection molding is avoided.

“In-Mold-Film-Decoration in this field of application allows the production of complete car body parts, which may optionally include rear light covers as functional surfaces.

Optionally, the PMMA film printed with a transparent elastic lacquer may be sprayed with transparent, thermoplastic carrier materials in this application prior to molding to increase stiffness to protect the lacquer against the hot, high-pressure melt of the thermoplastic material used for spraying.

Special, very economical design "In" · 8 · 8

8

Mold-Film-Decoration employs a combined molding die tool, which is used in a single process based on printed foils in the form of a roll of both film forming and injection molding. This method is generally called "Film-Insert-Molding".

When PMMA foils are used to decorate injection molded parts with Film-Insert-Molding, high demands are placed on PMMA foil material:

- good handling in the printing process, ie. sufficient ductility

- high surface hardness (at least the hardness of the HB pencil) to avoid scratching of moldings decorated with PMMA foils

- high surface gloss (measured according to DIN 67530)> 120

- slight haze due to moisture <2% mist according to the method described on page 15

- low surface haze <1.5%

- extremely low number of gel particles max. 1 gel particle per 200 cm ²

- high weather resistance; comparable to standard PMMA

- sufficient absorption of UV-light; UV absorption in the range 290 to 370 nm <1%.

BACKGROUND OF THE INVENTION

DE 38 42 796 (Rohm GmbH) describes PMMA-based films

PMMA-molding materials with small particle size of elastomer and high content of elastomer. The films according to the invention are not

-5on the parameter "surface hardness, can be made from this molding mass."

WO 96/30435 and EP 763 560 (Mitsubishi Rayon) disclose the production of PMMA films up to 0.3 mm thick based on a particular PMMA composition: impact modifier based on a certain particle diameter polybutyl acrylate, PMMA polymer matrix and (optionally) addition melt modifiers (polymer I).

The film is produced in a single-roll process (so-called chilled roll extrusion), in which the thermoplastic melt is contacted with a single metal roll during cooling and solidification and cooled. It should be noted that the thermoplastic melt cannot be formed between two metal rollers to produce films of the desired thickness.

This process has significant disadvantages over the two-roll process, which have a decisive influence on the quality of the film. The gel particles, which in principle tend to form impact-modified PMMA molding compositions, do not press under the surface when forming on a single cooled cylinder, unlike the two-roll (polishing) process, and thus remain visible as an optical defect. They are particularly disadvantageous in the subsequent printing process in the production of the decor foil, in which clearly visible gaps appear in the region of the gel particles. Further, the surface of the film facing away from the cooled roll, freely cooled in air, exhibits an observable surface haze due to the varying volume contraction of the elastomer particles and PMMA matrix. This creates a surface structure of “hills and valleys” that scatter light and cause a disadvantageous effect • φφφ

-6Φ φ φ φ φ φ φ φ φ φ alu alu alu alu alu

DE 195 44 563 (Rohm GmbH) discloses the impact resistant PMMA molding compositions used in the production of the films according to the invention.

DE 40 18 530 (Rohm GmbH) discloses a process for the production of solid sheets or foils with a thickness of less than 1 mm from thermoplastic plastic having a glass transition temperature> 50 ° C. Smoothing is achieved by guiding the film on the endless belt. The sheets or sheets obtained are practically free from orientation and birefringence.

EP 659 829 (Rohm GmbH) discloses a weatherproofing film and moldings coated therewith, which in addition to weathering also has the role of absorbing UV radiation. It consists of a hard phase of PMMA and a damping phase, the UV-absorbing substance.

EP 391 193 (Bayer AG) discloses a process for producing on both sides a glossy, optically isotropic extrusion film having a thickness of less than 0.6 mm, which is either

1. produced by extrusion and subsequent calendering between a lacquered elastic cylinder and a high-gloss steel cylinder; or

2. is molded in two extrusion steps, the first step being produced by extrusion and subsequent calendering between a brushed anesthetic roll and a high-gloss steel roll of foil, on the one hand highly glossy and matt on the other. In the second extrusion step, the film produced in the first step on the matt side is coated with a melt of the same thermoplastic plastic, the coated film thus obtained is

9

-79 9 9,999 9,999 9

9 9 99 9

999 99 99 99 99 99 again calenderes between two high-gloss steel rolls and the ground elastic roll, the high-gloss side of the coated film facing the roll of the ground elastic material.

Both processes which are both technologically demanding and associated with high production costs, according to the prior art, are unusable for the production of a double-sided foil between two high-gloss steel rollers, due to the extremely high and difficult to control forces in the rolling nip.

The method 1 has the disadvantage that it is not commercially viable, since the lacquer layers on the rubber rollers become brittle very quickly due to the high melting point. To avoid the effects of high melting temperatures, lacquered rubber rollers can be cooled in a water bath, but moisture leads to a disadvantageous effect on the surface quality of the film.

Method 2 exhibits an extremely unfavorable economy, since the production of the film must be carried out in two extrusion steps. Furthermore, extrusion coating of the film with a melt and subsequent calendering, particularly in the desired thickness range according to the invention, further leads to unfavorable surface properties.

EP 195 075 (Exxon) describes a process for producing a film of 10-85 wt. % elastomer and 90-15 wt. a polyolefin in which the extruded strip is passed through a slot of the counter-rotating rollers at a temperature above the softening point. One of the rollers is a high-gloss chilled roll and the other roll is a high-gloss rubber surface, the film being cooled.

The films thus obtained have a thickness of between 25 and 250

-8φφ φφ φφ micrometers (10 ' ⁶ m). The pressing forces are not described here, the disadvantages described in the discussion of EP 391 193 also exist here.

EP 212 355 (Bayer AG) discloses a polycarbonate film which is optionally printed with a glue-free polyurethane layer. The foils are one-sided matt or one-sided structured by printing and spraying structured chilled.

They are pulled through matt or rollers. The films thus obtained are:

A copolymer of acrylonitrile, butadiene and styrene is used as the plastic for injection molding.

EP 294 705 (Rohm GmbH) discloses a process for producing double-sided glossy films which uses as smoothing element an already glazed film which is pre-fabricated and recycled in this process.

A. Huemer (Kunststoffe 87 (1997), 10, p. 1351 et seq.) Discusses the advantages and disadvantages of the arrangement of the smoothing rolls, as well as H. Gross (Kunststoffe 87 (1997), 5, p. 564).

Huemer states that “higher pressure experiments fail because neither the residence time in the roll nip nor the polymer relaxation time is changed.

The measures Huemer describes (the correct ratio of nozzle exit speed and draw-off speed) is not enough to obtain films with high surface quality. As Huemer infers, the smoothing of the surface is not required as low as possible the pressure in the rolling nipple, but as high as possible.

SUMMARY OF THE INVENTION

Thus, there is a need to create economically efficient workers

-9 • Φ φ · φφφ · Φ «9

4 4 4 4 · 44 9 4 9

444 44 44 944 99 4 • 4 4 4 ·· ·· 4 ·

9 9 9 4 4 9 94 4 4 44 Large scale production method for the production of foils <0.3 mm thick from impact-resistant PMMA molding materials, which in addition provides a highly gloss foil on both sides, with almost gel-free surface quality and sufficient surface hardness for decorating. Furthermore, the film must be capable of being processed reliably and economically in the printing process as well as in the in-mold-film-decoration process, and must have adequate ductility accordingly.

It was therefore necessary to pay close attention to the correct choice of PMMA component, especially regarding the balance between surface hardness and ductility.

The following PMMA film properties necessary for surface decoration can only be achieved if:

polybutyl acrylate is used as the basis of weather-resistant impact modifiers the impact modifier used exhibits a smallest particle size of the active elastomeric phase (particle size range) the impact modifier used can, based on its morphological structure (clear distribution of tough and elastomeric phase) (as large as possible particle size) is used at relatively large dilution to provide the minimum necessary surface hardness for the film raw material by using a special molding material process that allows sufficient separation of the water-soluble polymerization auxiliaries from production by integrated coagulation of impact resistance modifiers impact modifiers,

- 10 • 4 44 44 44 44 · · · 4 4 4 * · 4 4 4 4 · 44 4 44 44 44 ·· 444 4 · 4

4444 4444 · 44 4 · 44 44 thus ensuring only a slight tendency to film haze due to water vapor.

good processability in the printing process (for film-InsertMolding, decorative printed PMMA films are mostly used), ie sufficient ductility high surface hardness (at least the hardness of the HB pencil) to prevent scratches of molded PMMA films

- high surface gloss (measured according to DIN 67530)> 120

- slight haze due to moisture <2% mist according to the method described on page 15

- low surface haze <1.5%

- extremely low number of gel particles max. 1 gel particle per 200 cm ²

- high weather resistance, comparable to standard PMMA

- sufficient absorption of UV-light; UV absorption in the range 200 to 370 nm <1%.

The production of the impact resistant PMMA molding compositions used is described in DE 195 44 563 (Rohm GmbH).

Further, the film forming process according to the invention is necessary to ensure high quality of the film (extremely low number of gel particles, high surface gloss, high weather resistance, low surface haze). The aforementioned combination of properties is not possible by the extrusion method on the cooled roll, as is usual for the films in the claimed thickness range.

The production of the film according to the invention is carried out by means of a special shaping method based on the technique of smoothing

9

9 9 9 999

9 9 9

Using a special pressing system and a pair of specially polished, mirror-polished rollers, in the rolling slot of which the film according to the invention is formed. Up to now, only considerably thicker films have been produced by the smoothing rolling technique (d> 0.3 mm; see "Folien fur thermogeformte Verpackungen, VDI-Verlag, 1992)".

For the production of the films according to the invention (thickness range 80 to 300 µm, preferably 95 to 250 µm, particularly preferably 105 to 250 µm), extremely high contact forces in the cylindrical slot are necessary, which cannot be realized by the structures used up to now. 1, or by conventional hydraulic pressure). The hydraulic thrust, which, moreover, is to be exerted only approximately by these thrust forces, is considerably more structurally demanding than the invention. Surprisingly, high contact forces have been exerted by means of the construction according to the invention: One of the rollers forming the smoothing slot is fixedly fixed in the smoothing rolling mill. The second, displaceable cylinder is connected to the rods located on the bearing journals by means of two parallel drives (electric or hydraulic) by means of a worm gear (see Fig. 2).

In this way, for the desired gap between the rolls, the opening of the rolling gap is prevented by the melt pressure. The maximum pressure attainable in this way is 1500 N / cm.

The melt produced by a single or twin screw extruder (melt pumps may optionally be used to maintain the melt flow constant) is fed to the molding process of the invention by means of a die designed for the extrusion of the film. The melt is shaped as defined

-12 * 9 · 9 • β 9 9 • 9 9 β β β 9

999 99 9

9 9 9 9 9

999 99 99 · 9 99 99 Rolling nip and smoothing and cooling by means of surface tempered mirror-polished rollers (roughness depth RA 0.002-0.006, RT = 0.02 - 0.04, measured according to DIN 4768). In this case, the geometric shape of one or both rollers is ground in a collared manner, deviating from the cylindrical shape. The rim is crucial for evenly distributing the thickness across the width of the film.

Definition of 'bombing: parabolic diameter increase from cylinder edges to center. References: Hensen, Knappe, Patente: Kunststoff-Extrusionstechnik II, Extrusions-Anlagen, HanserVerlag, 1986. The broom must be adapted to the thickness and width of the film to be achieved (i.e. there is no universally applicable bombardment).

Alternatively, the following design measures may be taken to ensure uniform thickness distribution:

- Ax-Crossing

- Roll-bending

These two methods are unusual in smoothing mills as they involve high construction costs. They are usually used on calendering machines.

The process according to the invention results in a double-sided high-gloss film almost free of gel particles with excellent surface properties.

The process according to the invention can also be used for the production of polycarbonate films with excellent surface properties.

-13 * φ φ φ · • • φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ φ · · φ φ

In the two-roll process, the elestomer-modified PMMA melt is formed between two tempered steel rolls, the surface temperature of the steel rolls being below the glass transition temperature of the PMMA matrix polymer used. This gives a preferential orientation of PMMA matrix molecules (having a considerably higher setting driving force compared to the elastomeric phase) on the metal surface or the metal surface. film, thereby achieving a high gloss film surface with negligibly low haze.

The two-roll process further provides considerably better weathering performance, as the smooth film surfaces are less sensitive to erosion supported by UV light.

It is certainly possible, by suitable selection of extremely small particle size modifiers (as described in DE 42 796), to realize double-sided high-gloss film surfaces also by extrusion onto a cooled roller. However, they exhibit, for PMMA films produced by extrusion onto a cooled roll, the typical formation of gel particles, which is disadvantageous for surface decoration.

Furthermore, it is necessary, in order to ensure sufficient ductility of the film, with decreasing elastomeric particle size, increasing the elastomer content, which again adversely affects the surface hardness which is essential for decorative use (the minimum requirement is pencil hardness HB, preferably at least H, particularly preferably 2H ).

The optimum temperature range for thermoplastic, non-crystalline plastics is different between the glass temperature (ET, Einfriertemperatur) and the plastic-viscous region.

- 14flow. In order to achieve a high surface gloss, the surface temperatures of the smoothing rollers need to be set lower than the glass temperature during the smoothing process. Consequently, the sheets of thermoplastic materials with the harder molded into a film, the greater the temperature difference between the rollers (must be less than the glass transition temperature T _g), and the optimum thermoforming temperature range.

As can be seen from H. Saechtling, Kunststoff-Taschenbuch, 21st edition (1979), Fig. 99 on page 166, for the above reasons, the thermoforming of thin films with high gloss surfaces in the case of polycarbonate in the case of polymethyl methacrylate.

For the extrusion of polycarbonates, the minimum thickness of about 120 μΜ is achievable, and for PMMA about 100 μτη. As the thickness increases, the necessary pressing forces increase exponentially.

considerably more difficult than that

Furthermore, the thermoforming of the film by the claimed smoothing process is easier to implement in the case of thermoplastic materials, the wider the temperature range for optimum thermoforming. Since a high temperature gradient is established when the molded melt film passes through the smoothing nip, the molded thermoplastic must have a reasonably wide range of thermoforming temperatures. Consequently, it is practically impossible to process thermoplastics such as PP or PE into the claimed films.

Test methods

The E-modulus, tensile strength and elongation at break were tested according to ISO 527-3, the clamping length was 60 mm and the test speed was 50 mm / min.

The hardness of the pencil was tested according to ASTM D 3363-92a.

The degree of gloss was measured at 60 ° according to DIN 67530.

The haze was measured according to ASTM D 1003. To calculate the surface haze, the haze of the film after two-sided treatment with silicone oil was subtracted from the haze measured in the unprocessed state.

Determination of the number of gel particles is an internal method of the firm. Rohm (Qualitatssicherung-Arbeitsanweisung 1/021/220).

Gel particles are dark / light flashing particles, visible through magnification as the specimen is zoomed in and out. They are mainly due to the high molecular fractions inevitable in the melting process, or, as in the case of the impact-modified PMMA, by aggregation of the elastomeric particles of the impact modifier component.

The gel particles were enumerated over an area of 200 cm ^{2 of} foil using a Copea CP-3 particle counting device from Agfa Gaevert.

Haze: Moisture films were placed over 60 ° C (90% humidity) over 96 hours of warm water. Subsequently, the haze was measured according to ASTM D 1003.

DETAILED DESCRIPTION OF THE INVENTION

Production of used impact-resistant molding material and its

-1644,563 (Rohm GmbH).

φ · · · · · r r r r r r r r r

a methyl methacrylate / ethyl acrylate / composition is described in DE 195

Used raw materials

Latex dispersion as a ternary emulsion polymer

Component 1: Allyl methacrylate copolymer 95.7 / 4.0 / 0.3 (w / w)

2nd component: butyl acrylate / styrene / allyl methacrylate copolymer

82/17/1 (w / w)

3rd component: copolymer methyl methacrylate ethyl acrylate 96/4.

The weight ratio of the three components is 23/40/30 (by weight). The latex dispersion has a solids content of 45% by weight.

The matrix polymer 1 is made by continuous polymerization, with an average molecular weight (weight center) of 110,000 Daltons. It is a copolymer of 96 wt. % methyl methacrylate and 4 wt. methyl acrylate.

The matrix polymer 2 is produced by batch polymerization, it is a copolymer of 80 wt. % methyl methacrylate and 20 wt. butyl acrylate. Molecular Weight (Weight Center) 270,000 Dalton.

The matrix polymer 3 is made by continuous polymerization. Mean molecular weight (weight center) 110,000 Dalton. It is a copolymer of 99 wt. % methyl methacrylate and 1 wt. methyl acrylate.

Production of impact resistant PMMA molding compositions which are the basis for Examples 1, 2 and 4

The preparation of the impact resistant PMMA molding compositions for Examples 1, 2 and 4 is carried out in two steps. In a first step, the impact resistant blank of the molding composition is produced using a combined coagulation / coupling device. In a second step, the molding stock in the twin-screw compounder is mixed with the matrix polymer 2 to form the final film raw material, the mixing ratio of the molding stock blank to the matrix polymer 2 being 1: 1, adding 0.3 wt. Tinuvin P (benzotriazole-based UV absorber, manufactured by Ciba-Geigy).

Step 1 is carried out in a device consisting of two successive extruders, in which a latex dispersion is dewatered in a first extruder and bonded to a portion of the "matrix polymer 1" which is fed as a melt. In the second extruder, which functions as a bonding and degassing extruder, the addition of a major amount of the matrix polymer 1 is effected by means of a side feed. At the end of the degassing zone, bleaching and anti-yellowing stabilizers are added via the masterbatch. 4 ppm of Ultramarinblau 31 and 14 ppm of Ultramarinviolett 11 are added, based on the molding stock produced. 40 ppm of sodium hypophosphite are added as a yellowing stabilizer. The weight ratio of dispersion to matrix polymer is 82 to 63.

Production of impact resistant PMMA molding compositions which are the basis for Example 3

Production of impact resistant PMMA molding compositions for example

- 18 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · It is carried out using a combined coagulation / coupling device consisting of two consecutive extruders. In a first step, the latex dispersion is dewatered and bonded to a portion of the &quot; matrix polymer 2 &quot; In the second extruder, which functions as a bonding and degassing extruder, the addition of the remaining amount of matrix polymer 2 is effected by means of a side feed. At the end of the degassing zone, the bleach, the yellowing stabilizer and the UV absorber are added via the masterbatch. 4 ppm of Ultramarinblau 31, 14 ppm of Ultramarinviolett 11, 40 ppm of sodium hypophosphite and 0.5 wt. Mark LA 31 (UV-absorber based on benztriazole, manufactured by Asahi-Denka). The weight ratio of dispersion to matrix polymer is 42/81.

Production of films according to examples 1 and 3 (according to the invention)

The melt is produced by means of a single screw extruder with a diameter of 120 mm and is fed through a flexible lamellar nozzle (1500 mm width) dimensioned for the film extrusion to the polishing mill according to the invention. The vane nozzle slot adjustment is 0.8 mm. According to the invention, the smoothing mill is designed, by means of a special construction (see FIG. 2), to exert high contact forces in the rolling nip (see FIG. 2).

One of the rollers forming the smoothing slot is fixedly fixed in the calendering stand. The displaceable cylinder is connected to two rods mounted on the bearing blocks of the cylinders by means of two parallel worm-drive electric drives. In this way, an opening force of 1500 N / cm is prevented from opening • 4 · · · ····

4 4 4 4 4 4 44 44 44 44 44 44 44 44 44 44 44 4 4 44

-19 roll slots in the production of 0.125 mm thick film by the pressure caused by the cooled melt. The melt is shaped in the rolling nip and polished and cooled through the surface of the polished mirror-polished, tempera- ture below the PMMA glass polymer temperature (roughness depth RA = 0.004). In this case, one of the two rollers is crimped. Bombage is 0.1 mm.

The result is a two-sided, highly glossy film free of gel particles with very little opacity. The film is imprinted with the desired pattern and then processed in-mold-film-decoration to the desired molded molding.

Production of foil according to example 2 (comparative example, extrusion method on a cooled cylinder analogous to the cited patent EP 763 560, Mitsubishi)

The melt is produced by means of a single screw extruder with a diameter of 120 mm and is fed to a film forming apparatus on a cooled roll by means of a flexible lamella nozzle of 1500 mm width. The vane nozzle slot adjustment is 0.8 mm.

The melt film is deposited on the surface of the cooled cylinder and cooled. As a result, the film, compared to the films produced according to the invention, has a relatively low surface gloss, a high number of gel particles, a low brilliance and a significant surface haze (see Table 1).

Production of foil according to example 4 (comparative example, smoothing mill with press lever, see Fig. 1)

-20The melt is produced using a single screw extruder with a diameter of 120 mm and is fed to a smoothing rolling mill equipped with a knuckle lever via a flexible vane nozzle of 1500 mm width. The vane nozzle slot adjustment is 0.8 mm.

The result is a product with respect to the surface properties corresponding to the films of Examples 1 and 3. However, with a knuckle clamping system, the desired film thickness <300 µm is not achieved. This clamping system does not exhibit the stiffness necessary to exert an extremely high clamping force due to the necessarily incompletely straightened joint (a fully straightened joint under load requires an infinitely large opening force). This is of decisive importance at high counter forces (developed by the thin film of the melt in the production of the film).

Example 5

Laminating the PMMA films produced according to the invention according to Examples 1 and 3 with a carrier material

The ABS melt film is produced by means of a single screw extruder with a diameter of 90 mm by means of a wide slot nozzle being fed to a smoothing rolling mill. The vane nozzle slot adjustment is 1.2 mm.

In the smoothing slot, a PMMA film, printed e.g. with a so-called &quot; carbon pattern &quot; and an ABS adhesion coating, is laminated with an ABS melt film of 240 [deg.] C warm. The PMMA film according to the invention is suspended on a brakeable winding shaft. To ensure running without creases respectively. proper lamination, the plexiglass film according to the invention is guided

-21 through the so-called "expanding cylinder". The resulting film laminate has a total thickness of 0.50 mm, of which 125 nm is the PMMA layer. The withdrawal speed from the polishing mill is 5 m / min. The laminated foil is used for surface decoration of moldings by means of the so-called "Insert-Molding" process. The resulting injection molded parts have an attractive surface pattern due to the finishing press used. Due to its valuable surface properties, PMMA film is an ideal substrate for valuable paint systems.

· 9 «9 9 9 9 9 9« 4 4 4 4 4 4

gel particles / 2 0 0 cm ² O 15 Dec 0-1 the claimed thickness is not possible surface fogging (%) 1.1 rH CM O gloss 60 ° 133 108 136 hardness pencils IH fn [0100] 2H stretching at breakage (%) 00 r- tensile strength (MPa) ⁶¹ 67 83 E-module (MPa) 1591 1603 1530 property 1 * CN * cn <4 · Example C.

List of reference marks

Giant. 1

100 flexible vane nozzle

110 rigid roller

120 movable roller

130 lever lever

140 pneumatic cylinder

150 foil

Giant. 2

200 flexible vane nozzle

210 rigid roller

220 movable roller

230 rod

240 worm gear

250 foil measuring box

Giant. 3

310 cylinder stroking rolling stool 320 cylinder stroking rolling stool 330 cylinder stroking rolling stool 340 PMMA- foil 350 expansion cylinder 360 foil

pp 2000 ~ 206 &

Claims (9)

1. A process for the production of two-sided shiny foils of thermoplastic plastics in the range of 80 to 300 μιυ thicknesses by means of a special feature characterized therein. In the rolling process, the rolling mill is smoothed so that the smoothing is sized for high contact forces in the rolling nip. Method for producing double-gloss thermoplastic plastic films in the thickness range of 80 to 300 μιτη by the special smoothing rolling process according to claim 1, characterized in that the temperature range of the optimum thermoforming is at least 15 K. Production of double-gloss foils of thermoplastic plastics in the thickness range of 80 to 300 μπι by means of a special smoothing rolling process according to claim 1, characterized in that the temperature difference between the vitreous temperature and the optimum temperature range of max. 50 K. 4. The production of double-gloss films of thermoplastic plastics in the thickness range of 80 to 300 μπι of the rolling process, the plastic being by means of a special smoothing process characterized in that the thermoplastic polymethyl methacrylate or polycarbonate. PMMA. Production of double-gloss films of thermoplastic plastics in the thickness range of 80 to 300 μιυ by the special smoothing rolling process according to claim 1, characterized in that the thermoplastic plastic is -256. The method of claim 1, wherein the roller is bumped. Use of a film produced by the process according to any one of claims 1 to 6 as a decorative film for injection molded parts. Injection molded thermoplastic molding composition, characterized in that it is decorated with a film produced according to any one of claims 1 to 6. The article of claim 8, wherein the thermoplastic molding composition is a transparent molding composition. Product according to any one of claims 7 to 9, wherein the film produced according to any one of claims 1 to 6 is laminated with a thermoplastic carrier material prior to use as a decorative film. 11. Use of foil, made way according to any of the claims 1 to 6, such as decorative foil for extruded moldings. 12. Use of foil, made way according to any of the claims 1 to 6, such as decorative foil for extruded reshaped moldings. WO 99/29766