DE2154643A1 - Process for the production of thermoset molded bodies with a glossy, stain-resistant surface - Google Patents

Description

Process for the production of thermoset molded bodies with a glossy , stain- resistant surface. ^

In the Swiss patent specification 450 * 715 or the British one Patent specification 913M45 describes a method / in which undecorated or decorated with cover sheet press parts from Y / thermosetting synthetic resins, especially melamine resins, with

. ■ ■ -

a glossy surface layer made of melamine-foraldehyde resin bzv / .. melamine formaldehyde resins modified with aceto- or benzoguanarain covered v / earth.

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In this known method, for example, a melamine molding compound is preformed in a hot mold under pressure and partially hardened, the mold opened and a decorative film impregnated with melamine resin, for example, inserted, the mold put under pressure again and the film hardened. The mold is used again for the additional surface treatment opened and a well-flowing e.g. melamine-formaldehyde resin or benzoguanamine-melamine-formaldehyde resin sprinkled on the under pressure, the surface of the pressed part is covered with a crystal-clear coating and cures.

Such pressed parts look decorated and undecorated, similar to porcelain and are also used as tableware or canteen dishes Use.

The surface treatment was an improvement at the same time the known, relatively poor resistance of cured melamine-formaldehyde resins or with aceto or Benzoguanamine modified melamine-formaldehyde resins aimed against certain foods. This is particularly noticeable Cups made from melamine molding compounds become stained by coffee. Certain components in coffee take hold: the surface of melamine resins and, somewhat reduced, the modified melamine resins described and cause a brown to black discoloration that can only be removed with special chemical agents. But there in restaurants and Canteens cleaned the dishes in automatic washing machines

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there is usually a lack of time and facilities for such special treatments. Therefore find dishes with such Aminoplast resins only limited use in the tableware sector.

In the Swiss patent specification 450 * 715 and the British Patent specification 913 * 445 is stated that after the. surface finishing processes described there reduce the susceptibility Reduced by cups made of melamine resin against coffee stains will. The test conditions specified there (cooking during 1 hour in coffee solution, followed by a rinse cycle in a domestic dishwasher and subsequent drying for 1 hour at 49 ° C.) are, however, not too strict to allow usable conclusions to be drawn to allow for practice where much tougher conditions are encountered. It has been shown that for the practice of the well-known surface glazes based on Melamine or melamine benzoguanamine resin one at nowhere near sufficient improvement in coffee stain resistance bring: for a practical treatment for 120 hours in 85 C warm 3% coffee or black tea solutions is this surface treated by the known method, Quality dishes have consistently been strongly discolored brown and have become completely unsightly.

It has now surprisingly been found that with certain storage-stable granular or powdery meltable epoxy resin hardener mixtures or epoxy resin hardener precondensates crystal clear =

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light-stable and absolutely stain-resistant surface coatings on pressed parts made of thermosetting plastics, especially Aminopl == resin such as melamine or urea resins. The epoxy resin hardener systems, which are suitable for the purposes of the invention, are known as such in part ", they must be determined Have physicochemical parameters: What is required is good storage stability of the one-component system made of resin k and hardener at room temperature, a softening point in a certain range (50-130 ° C), a fast curing time at elevated temperature (less than 1 minute at 150 ° C), good flow at processing temperature (Closing time according to DIN 53 * 465 at a pressure of 250 kp / cm and a temperature of 150 C from 1 to 15 seconds) Furthermore, the cured epoxy resin hardener system must have good light stability (at least grade 7 of the internaticr.alen Blue scale after 300 hours Xenotest DIN 54'004). It is also advantageous if the hardened resin-hardener system has good resistance to boiling water and above average has good adhesive strength on substrates made of hardened melamine or urea resin. For many purposes it is also desirable that the hardened resin-hardener system is crystal clear or transparent.

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The present invention thus provides a process for the production of a molded article with a glossy, stain-resistant surface from a fusible, thermosetting synthetic resin , optionally tabletted, meltable and thermosetting coating resin is applied to the surface of the object shaped in this way and the production of the molded body is then continued in such a way that the coating resin, which has meanwhile melted, flows evenly over the surface of the object, and the resin spread thereon together with the base as a coherent object is cured, characterized in that a composition is used as the coating resin which, as the synthetic resin-forming component, is a solid, meltable epoxy resin-hardener mixture or a solid, meltable epoxy resin-hardener precondensation at, the synthetic resin-forming component mentioned is storage-stable at 25 ° C, has a softening point in the interval between 50 ° and 130 ° C, a closing time according to DIN standard 53 '465 at a pressure of 250 kp / cm. and at the temperature of 150 ° C has from 1 to 15 seconds, and which cures at a temperature of 150 ° C to an insoluble and infusible crosslinked synthetic resin, and further wherein the synthetic resin obtained by curing said synthetic resin-forming component has a light stability which , tested after 300 hours of xenotest, at least grade 7 on the blue scale of the

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. BATH

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Reached the lightfastness standard according to DIM standard 54'004.

The synthetic resin obtained by curing the synthetic resin-forming component should preferably be resistant to boiling water Substrates of cured aminoplast resins, such as melamine or urea resins, adhere well and are also crystal clear or transparent be.

Excellent as epoxy resin hardener systems of the above

P type described are mainly those based on triglycidyl isocyanurate. For example, the solid fusible ones are suitable.

Precondensates (so-called "B-stages") made from triglycidylsocyariurate and an amount of a cycloaliphatic polyamine sufficient for complete curing.

The solid, curable mixers are also outstandingly suitable.

from triglycidyl isocyanurate and one sufficient for curing Amount of a solid adduct hardener containing amine groups from an epoxy resin and a stoichiometric excess

^ of, for example, 2 equivalents of primary amine groups per 1 equivalent of epoxy group of a cycloaliphatic primary polyamine. Cycloaliphatic polyamines suitable for the production of such adduct hardeners are, for example:

1,2-diaminocyclohexane, bis (4-aminocyclohexyl) methane, Bis (3-methyl-4-aminocyclohexyl) methane, 3-aminomethyl-3,5,5-trimethyl-cyclohexylamine-1 ("isophoronediamine") 2,2-bis (4-aminocyclohexyl) propane or N-cyclohexy1-1,3-diaminopropane.

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Suitable as epoxy resins for the production of adduct hardeners For example, polyglycidyl ethers of polyphenols such as resorcinol or 2,2-bis (p-hydroxyphenyl) propane ("diomethane"), e.g. a diomethane diglycidyl ether with an epoxide content of 5.1 to 5.5 epoxide equivalents / kg.

The adduct hardeners mentioned from cycloaliphatic polyamines and In addition to triglycidyl isocyanurate, epoxy resins also form with other known epoxy resins, e.g. solid polyglycidyl ethers of diomethane (epoxide content 2.3-2.6 epoxide equivalents / kg), Epoxy resin hardeners — Sy Stars .

When using the epoxy resins and hardeners listed above, care must always be taken to ensure that they do not contain any Contain impurities that reduce light stability. For the production of ready-to-use epoxy resin hardener compositions is either the solid hardener, e.g. a solid amine adduct hardener or an anhydride hardener such as phthalic anhydride mixed with the solid epoxy resin, e.g. triglycidyl isocyanurate, and put in a suitable mixing and grinding device, e.g. a ball mill, advantageously to a fine-grain powder processed.

The epoxy resin-hardener mixtures can be used both unfilled tel quel, ie as "pure resin", and together with customary modifying additives, such as above all fillers, optical brighteners, pigments and coloring substances, such as

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Titanium dioxide, iron oxide, cadmium red are processed. the Epoxy resin hardener powder can be granulated if desired and / or compressed into tablets. Instead of the epoxy resin-hardener mixtures The solid precondensates or B-stages from epoxy resins such as triglycidyl isocyanurate can also be used analogously and e.g. cycloaliphatic polyamines.

The finished compositions based on epoxy resin are exactly W the same for the surface treatment of compacts processed as known for this purpose aminoplast resins: they have an excellent fluidity and the surface coatings produced therewith show analogously to the commonly aminoplast resins used a good adhesion to the compact or the cover sheet as well as good hardness and good scratch and abrasion resistance. In contrast to the known coatings based on aminoplast resins, the coatings based on the epoxy resin compositions used according to the invention are extremely resistant to coffee, tea and other household foods and beverages. Protein and starchy food does not adhere to these surfaces. The coatings are also very lightfast, which is essential for use in the tableware sector.

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BATH ORIGINAL

Determination of the light stability in the Xenotest

A hardened resin film made of the synthetic resin to be tested is glued to a test strip made of cardboard and together with a Light fastness measure according to DIN standard 54'004 for 300 hours with filtered xenon arc light in a xenotest exposure device according to DIN 54'004 ("Cassella" system, original "Hanau") in the spiral run (samples are rotated simultaneously around their own longitudinal axis and in a circular path around the exposure source rotated) exposed. The light fastness measure consists of a scale of 8 blue type colors with different degrees of light fastness on wool, where lightfastness type 1 (= grade 1) is a very low and lightfastness type 8 (= grade 8) a very high one Means lightfastness.

Any change in color or shade of the synthetic resin film is rated in comparison to the change on the blue scale of the lightfastness standard.

Determination of the closing time according to DIN 53 * 465

To determine the closing time, cups are removed from the " test molding compound in a pressing tool according to the picture in DIN standard 53 * 465. The tool is on a Temperature of 150 C +, 1 ° C heated and the press, which one

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has a hydraulic drive that works smoothly, the pressure is set to 250 kp / cm. The temperature of the molding compound before filling is 20 ° C £ 5 ° C. A molding compound sample corresponding to the weight of the finished cup with a Add 5% of the cup weight is poured into the opened tool and the tool is closed. The time from the beginning of the filling of the molding compound to the beginning of the pressure increase should be 15 seconds + 1 second be. The speed of the plunger until it touches the molding compound should be 2 cm / second +0.5 cm / second be.

The stopwatch measures the closing time from Beginning of the pressure increase, observed on the pressure gauge of the press, up to the standstill of the plunger, observed on one of the Press-mounted display device with leverage or on a dial gauge.

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badorksMl '

I. Manufacture of powder resins

Powder resin A

114.2 g of 1,2-diaminocyclohexane Cl mol) are in one Reaction vessel heated to 120 ° C and with constant stirring

187.3 g of a liquid epoxy resin mainly composed of diomethane diglycidyl ether and an epoxy content of 5.34 equivalents / kg, produced by reacting epichlorohydrin with 2,2-bis (p-hydroxyphenyl) propane (= diomethane) in the presence of alkali (= Epoxy resin I) mixed in for 30 minutes. The resinous adduct hardener (a) produced by the reaction is cooled and pulverized. To produce a powder resin, 100 parts by weight of the adduct hardener (a) obtained are mixed with 98.5 parts by weight of a crystalline glycidyl oxyocyanurate with an exnefn epoxide content of 9.3-9.4 equivalents / kg and ground in a ball mill.

The powder resin A obtained has a softening point (Kofier) of 70 ° C. and a closing time according to DIN 53,465 (250 kp / cm ² , 150 ° C.) of 2 seconds *; it hardens at 150 ° C. after 40 seconds to an infusible one and insoluble plastic.

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Powder resin B "

In the same way as above for the production of adduct hardener (a) to 210.4 g of bis (4-aminocyclohexyl) methane (1 mol) with 187.3 g Epoxy resin I (epoxy content = 5.34 Aeguival./kg) react. To produce a powder resin, 100 parts by weight of the adduct hardener (b) obtained are mixed with 74.7 parts by weight grind crystalline triglycidyl isocyanurate.

_fc The obtained powder resin B has a softening point (Kofier)

P ₀ 2

of 74 C and a closing time according to DIN 53'465 (250 kp / cm, 150 ° C) for 4 seconds; it hardens at 150 ° C after 35 seconds to an infusible and insoluble plastic.

Powder resin C

In the same way as above for the preparation of adduct hardener (a), 238.4 g of bis (3-methyl-4-aminocyclohexyl) methane (1 mol) are left with it 187.3 g epoxy resin I (epoxy content = 5.34 equivalents / kg) react.

100 parts by weight are required to produce a powder resin

^ of the adduct hardener obtained (c) with 69.7 parts by weight

co-grind crystalline triglycidyl isocyanurate. oo

^ The powder resin C obtained has a softening point (Kofier)

- »of 73 ° C and a closing time according to DIN 53'465 (250 kp / cm ² , O

^ 150 ° C) for 5 seconds', it hardens at 150 ° C after 45 seconds an infusible and insoluble plastic.

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Powder resin D.

In the same way as above for the production of adduct hardener (a) 170.3 g of S-aminomethyl-S / SfS-trimethylcyclohexylainin-l (1 mol) react with 187.3 g of epoxy resin I (epoxy content = 5.34 Aeguival./kg).

To produce a powder resin, 100 parts by weight of the adduct hardener (d) obtained are ground with 83.1 parts by weight of crystalline triglycidyl isocyanurate. The powder resin D obtained has a softening point (Kofier) of 75 ° C. and a closing time according to DIN 53'465 (250 kp / cm ² , 150 ° C.) of 2 seconds! it hardens at 150 ^° C. after 40 seconds to form an infusible and insoluble plastic.

Powder resin E

Analogously to the above for the preparation of adduct hardener (a), 238.4 g of 2,2-bis- (4-aminocyclohexyl) propane (1 mol) are allowed with it 187.3 g of epoxy resin I (epoxy content = 5.34 equivalents / kg) react.

To produce a powder resin, 100 parts by weight are required

O of the adduct hardener (e) obtained with 69.7 parts by weight <o

Grind J ₀ crystalline triglycidyl isocyanurate.

** The powder resin E obtained has a softening point (Kofier)

^ Of 72 ° C and a closing time in accordance with DIN 53'465 (250 kp / cm ^2, 150 ⁰ C) of 4 seconds, "it cures at 150 ° C after 50 seconds

to an infusible and insoluble plastic.

Powder resin F

20 g of crystalline triglycidyl isocyanurate and 10 g of bis (3-methyl-4-aminocyclohexyl) methane are mixed cold, carefully. Heated 80- 90 ⁰ C and rapidly spread in thin layers. After cooling, a solid, fusible precondensate ("B stage") is obtained / which can be ground to a powder.

The powder resin F obtained has a softening point (Kofier) of 75 ° C. and a closing time according to DIN 53 * 465 (250 kp / cm, 150 ° C.) of 4 seconds; it hardens at 150 ^° C. after 30 seconds to form an infusible and insoluble plastic.

Powder resin G

51.2 parts by weight of one mainly composed of the diepoxide of the formula

\ CH " CH " \ X CH- HC-CH ^ W. / ² t ■ / -0-C-CH CH Δ C. / / CH " CH \ _rH /
^LH 2

(= 3 '^' - epoxy-cyclohexyl-methyl) -3,4-epoxy-cyclohexane

carboxylate) existing, at room temperature, liquid cycloaliphatic epoxy resin with an epoxy content of 7.82 epoxy equivalents / kg are mixed with 18.4 parts of 5,5-diethylbarbituric acid (corresponding to a ratio of epoxy groups: NH groups = 2: 1) and 0.3 part of tetraethylammonium chloride mixed and stirred at 155 ° C. The reaction is terminated after 4 hours and minutes; the epoxy content of the end product is 2.90 epoxy equivalents / kg (theory: 2.82). The solid, pre-extended epoxy resin (= epoxy resin II) produced is pale ocher in color and crystal clear , it softens at 45-50 ° C and begins to flow at around 75 ° C. To produce a powder resin, 316 parts by weight of phthalic anhydride are ground to a powder with 1000 parts by weight of epoxy resin II.

The powder resin G obtained has a softening point (Kofier) of 68 ° C and a closing time according to DIN 53 * 465 (250 kp / cm, 150 ° C) for 12 seconds', it hardens at 150 ° C after 60 seconds to an infusible and insoluble plastic.

Powder resin H

159 parts by weight of an epoxy resin prepared by reacting epichlorohydrin with 2 _r 2-bis (p-hydroxyphenyl) propane in the presence of alkali, solid at room temperature and having an epoxy content of 2.4 epoxy equivalents / kg ^ epoxy resin III) are mixed with 100 parts by weight of the above be -

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milled adduct hardener (d) to a powder. The powder resin H obtained has a softening point (Kofier) of 70 ° C and a closing time according to DIN 53'465 (250 kp / cm, 150 ° C) for 6 seconds; it hardens at 150 ° C after 70 seconds to an infusible and insoluble plastic.

The following melamine powder resins were also used for comparison manufactured:

Powder resin J

In a three-necked flask equipped with a stirrer, thermometer and reflux condenser, 126.1 g of melamine (1 mol), 180.2 g of aqueous 30% formaldehyde (1.8 mol) are mixed cold and adjusted to pH 9.2 with sodium hydroxide solution (approx 3.6 ml NaOH In required). This mixture is heated to 90 ° C. within 15-20 minutes. At this temperature, the initially insoluble melamine goes into solution. At 90 C, the resin is then condensed until 10 ml resin syrup with 18 ml of water at 20 ⁰ C give a milky permanent turbidity. The condensation is then terminated by cooling, ie the resin syrup is cooled to room temperature within 20 minutes. Any impurities that may occur are removed by filtration. A portion of the Melaminharζlösung obtained is in a rotary evaporator at 40 ⁰ C in a vacuum to 80 wt.% Solids

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content concentrated, poured onto metal sheets and then dried in a vacuum drying cabinet under the same conditions to 1% by weight residual moisture. The glass-like foam obtained in this way becomes a fine powder in a mortar grated.

Powder resin K

Otherwise, proceed in the same way as with the one described above Production of powder resin J, but instead of 126.1 g of melamine, a mixture of 63.0 g of melamine and 62.5 g is used Acetoguanamine one. ·

Powder resin L

The procedure is otherwise the same as for the production of powder resin J described above, but you wear instead of 126.1 g of melamine, a mixture of 63.0 g of melamine and 93.5 g of benzoguanamine.

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II. Production of covering resins ("glazes")

1. Pure resin glazes Al - H 1 based on epoxy resin

In a 2 liter ball mill, half of it with balls is filled with various sizes

500 g powder resin A
15 g zinc stearate

5 g silica airgel (protected brand name

"AEROSIL")

Weighed in. This mixture is at room temperature during 24 hours, and the ready-to-use pure resin Glaze A 1 carried out.

The transparent pure resin glazes B1-Hl can be produced from the powder resins B - H in the same way.

2. Pure resin glazes Jl-Ll based on melamine resin

In a ball mill, 500 g of powder resin J with 0.5-2.5 g Stearyl alcohol weighed in, pebbled at room temperature for 24 hours, and the ready-to-use pure resin Glaze J 1 is discharged.

The pure resin glazes K 1 and L 1 can be produced in the same way.

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3. Pigmented glazes A 2 - H 2 based on epoxy resin

Ground in a 2-liter ball mill half of which is filled with balls of various sizes

150 g powder resin A
350 g titanium dioxide (rutile)
15 g zinc stearate

weighed in. This mixture is kept at room temperature during Balled for 48 hours and the ready-to-use, pigmented Glaze A 2 discharged. Leave according to the same working method the opaque, pigmented glazes B 2 - H 2 from the Manufacture powder resins B-H. In the manufacture of unpigmented and pigmented surface finishing resins from the powder resins A-H can be used in place of zinc stearate other release agents such as stearic acid or stearyl alcohol can also be added The amount of pigment to be regarded as the upper limit. Coloring substances and pigments such as nigrosine, Cadmium red, iron oxides are added.

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III. Production of surface-treated moldings

Example 1 '

A commercially available melamine molding compound for tableware, consisting of 60 weight percent of melamine-formaldehyde condensation product in .Molverhältnis 1: 2, 30 weight percent L · cellulose powder and residual lubricants, pigments and acid curing catalysts is introduced into a mold for plates of 19 cm, which at 155 C is held and for 60 seconds

cured under a pressing pressure of 350 kg / cm. Then it will be Open the mold and put a decorative film on the surface of the plate. The mold is closed again for 60 seconds and open again. Be on the center of the plate 1.5 g of the epoxy resin Glazes A 1 and the mold is closed again for 60 seconds. After the mold opened and the plate has been removed, the surface of the plate is smooth, hard and cohesive and has a high surface Shine. After 120 hours of soaking in a 3% solution at 85 ° C Coffee solution (soluble dry coffee powder) the surface was practically unchanged.

Plates with an equally high surface gloss and one the same Good stain resistance is obtained if, instead of the epoxy resin glaze A 1, an unpigmented epoxy resin glaze Bl-Hl or a pigmented epoxy resin glaze A 2 - H 2

used. """ _ΛΛ

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Example 2 .

a) Manufacturing of_Prüfglatten

_{60 g of the 7} commercially available melamine molding compound used in Example 1 are pre-hardened in a plate tool with a diameter of 140 mm and 2 mm thickness, the press is opened and then enough pure resin Glaze A 1 is sprinkled and pressed again to drive out a slight excess of resin.
The pressing conditions are as follows:

Press temperature 155 C

Pressing pressure 350 kg / cm

Pre-pressing time of the molding compound 60 seconds Press time of the Glaze 60 seconds

Test plates with the unpigmented epoxy resin glazes B1-HI are produced in an analogous manner. All surface finishing resins Al-H IfHessen very well and the ones from it The test plates produced have a flawless, glossy finish Surface.

For comparison, test plates made of the unpigmented melamine resin glazes Jl-Ll were also used under the produced under the same pressing conditions. The following table shows the composition of the resin component in the

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Glazes Jl-Ll can be seen:

description Composition in MoI Acetoguanamine Benzo-
guanamine formaldehyde Glaze J 1
Glaze K 1
Glaze L 1 melamine 0.5 0.5 1.8
1.8
1.8 1
0.5
0.5

b) Examination_and_examination results

The from the unpigmented epoxy resin glazes Al-Hl and from the unpigmented melamine resin glazes Jl-Ll The test plates produced were cut to 3 × 3 cm and placed in the following test solutions at a temperature of 85 ° C. for 120 hours inserted:

- 3% coffee solution (soluble coffee powder)

- 3% black tea solution (soluble dry tea powder) In addition, 1 sample each was tested for lightfastness in the Xenotest exposure device (300 hours exposure time) checked. It means:

Grade 1 = very poor lightfastness *, Grade 8 = very good lightfastness, i.e. no change.

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The results can be seen from the following table:

description Coffee' tea Lightfastness in 7-8 Xenotest (300 Hours) grade 8th Glazes Al-St. practically unchanged (Invention) unchanged changes 7-8 changes Glaze J 1 (comparison) dark Brown 4th Brown Gray Glaze K 1 (comparison) Brown Brown Gray Glaze L 1 (comparison) light brown

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Claims (5)

Claims 1. A process for the production of a molded body with a glossy, stain-resistant surface from a fusible thermosetting synthetic resin, wherein first such a synthetic resin, preferably a melamine or urea resin, is partially cured in the mold and then a granular or powdery, optionally tabletted, fusible and thermosetting Coating resin is applied to the surface of the object shaped in this way and the production of the molded body is then continued in such a way that the coating resin, which has meanwhile melted, flows evenly over the surface of the object and the resin spread thereon together with the base is cured as a coherent object, characterized in this that a composition is used as the coating resin which contains a solid, meltable epoxy resin-hardener mixture or a solid meltable epoxy resin-hardener precondensate as the synthetic resin-forming component, said synthetic resin-forming component e component is storage-stable at 25 ° C, has a softening point in the interval between 50 ° and 130 ° C, a closing time according to DIN standard 53 ^l 465 at a pressure of 250 kp / cm and at a temperature of 150 ° C of 1 to 15 seconds possesses and which at a temperature of 150 C to an insoluble and infusible, 209820/1066 networked synthetic resin cures and furthermore by curing said synthetic resin-forming component obtained synthetic resin has a light stability which, tested after 300 hours Xenotest, at least grade 7 of the Blue scale of the light fastness standard in accordance with the DIN standard 54,004 reached. 2. The method according to claim 1, characterized in that that the resin-forming component of the coating resin is a solid, fusible precondensate or "B stage" Triglycidyl isocyanurate and one sufficient for curing Amount of a cycloaliphatic primary polyamine is used. 3. The method according to claim 1, characterized in that that as a synthetic resin-forming component of the coating resin is a mixture of triglycidyl isocyanurate and one for the Curing a sufficient amount of a solid amine group-containing adduct hardener composed of an epoxy resin and a stoichiometric excess of a cycloaliphatic, primary polyamine is used. 209820/1066 4. The method according to claims 1 and 3, thereby characterized in that the synthetic resin-forming component of the coating resin is a mixture of triglycidyl isocyanurate and an amount of an amine group-containing adduct hardener from approximately 1 mole of S-aminomethyl-a ^ S-trimethylcyclohexylamine-1 and about 1 epoxy equivalent of a diglycidyl ether of 2,2-bis (p-hydroxyphenyl) propane with an epoxide content of 5.1-5.5 equivalents per kg is used. 5. The method according to claims 1-4, characterized in that that between the first partial curing and the application of the coating resin to the to be coated Surface a decorative film is applied to the surface and the arrangement is subjected to heat and pressure to cause a further partial hardening. 209820/1066