DE2102311C3 - Production of laminates or treatment of wood-based panels with layers of carrier sheets impregnated with phenoplast resin - Google Patents

Description

The invention relates to the manufacture of laminates with layers of carrier taps impregnated with phenoplast resin or the remuneration of Hol / u "orkstol! 'Plates with several layers vu.i mit I-thermoplastic resin-impregnated carrier sheets by fretting at elevated temperature.

The production of laminates or the treatment of wood-based panels with several layers of carrier webs impregnated with phenoplast resin in the above-mentioned manner is known. This is a ! A plurality of carrier webs impregnated with condensation resins together, if necessary under Pressed shaping. Also for surface coating of materials such as wood-based panels are often used between wood-based panel surfaces and decorative film, several layers of carrier webs impregnated with condensation resins. The color of these resin-impregnated carrier webs is either due to the inherent color of the used Synthetic resins or given by coloring the carrier web.

There are differences between those used for the production of laminates or multi-layer surface coating of materials required individual layers of the press package with regard to the resin used or the amount of resin on the carrier web, it can be difficult to resinify them To distinguish carrier webs from one another. This can lead to mix-ups between the individuals Carrier webs and thus lead to the wrong structure of the press package.

There are also dyes known that under pressing conditions at elevated temperature in the presence of phenolic resins show a color change and of the color of the crosslinked condensation resin are covered.

An example of such a dye is that commercially available under the name "paper congorot" red dye. If, for example, 0.05 to 2 percent by weight of this dye is added to a phenoplast resin precondensate, Depending on the amount added, the color can be clearly perceptible to intensely red. The soaked paper web is also red. The pressing conditions for the impregnated paper web cause a shift in color to yellow. This yellow shade is due to the inherent color of the Phenolic resin covered.

These dyes are used, for example, to color paper. With such Papers treated with dyes, however, have not been impregnated with phenolic resins so far. For the Einl'ärlumg it is sufficient to add 0.05 to 2 percent by weight of the dye to a phenoplast resin precondensate.

The invention is based on the object in the production of laminates described at the outset or a reliable l'nierscheidiing of different synthetic resins in the treatment of wood-based panels to ensure containing carrier taps.

ίο without the appearance of the finished Schichtsioffes or the wood-based panel is impaired.

The solution to this problem consists of the invention in the use of the dyes described, which under Preübedmgungen at increased Temperature in the presence of phenoplasts show a color change and are covered by the color of the linked condon shorts, in the production of laminates described at the beginning or in the tempering of woodworking panels to identify at least one of the phenoplastic / impregnated wear sheets.

If a laminate is built up from several layers of two different resinated carrier taps, it is sufficient to mix this dye in the production of one of the two types of hard carrier webs. In this way it is possible to keep the carrier webs apart safely before the pressing, without the color of the finished product being adversely affected by the addition of dye will. If a laminate is made from more than two types of hard carrier webs, so A corresponding differentiation can be achieved through the use of additional dyes or through different types of dyes Concentration of the same dye can be accomplished. The same considerations apply for the surface coating of materials by pressing together a plurality of Layers of resinous carrier webs under curing conditions.

The following example is intended to explain the subject matter of the invention in more detail:

example

It is a laminate made of several layers of two different resinated carrier sheets manufacture. The press package structure is as follows:

2 layers of a highly resinous carrier web. . . (A)

10 layers of a low-resin carrier web. . (B)

2 Lagon of a highly resinous carrier sheet. . . (A)

By impregnating a soda kraft paper (150gZm- ') with a commercially available alkali-catalyzed phenol-formaldehyde condensation product, the different resinated carrier webs (A) (320 g / m-) and (B) (220gZm-') are produced, with the phenolic resin for the impregnation of the carrier web (A) 0.5 ⁰ Zo paper congorot are stirred in. The resin turns red, and the carrier web (A) impregnated with this resin is also colored red and can thus be clearly distinguished from the resin-coated carrier web (B).

At the pressing conditions 15O ⁰ C. SOkp / cm- ', 8 min. Of the laminate is made from the cool Preßpaket. The finished product has the same brown color as a laminate produced analogously without the use of carrier webs marked with a dye.

Claims (1)

Claim: Use of dyes, which under test conditions at elevated temperature in the presence of Vi) H phenolic resins a color change / peculiar and of the color of the networked condensytioiishar / es are covered, in the production M) H laminates with layers from with Phenoplasi resin impregnated carrier sheets or in the treatment of wood-based panels !! With several layers of carrier balines impregnated with phenolic resin by pressing at an elevated position Temperature for marking at least one of the carrier balines impregnated with phenoplast resin.