SI21362A - Procedure of separate application of activator in fabrication of flat laminates based on soft polyurethane foam - Google Patents

Abstract

The invention discloses a procedure of separate application of activator in fabrication of flat laminates based on a soft polyurethane foam, where a polyol component (A') and an isocyanate component (B') are dosed into a vessel (205) in which the homogeneity of the mixture of components (A', B') is obtained by using a stirrer (N). The mixture is fed by means of a dosing pump (206) to a roll coating device (207) which is applying the reactant mixture in the form of a laminate film (207a) onto an abrasive material (213). An activator (C') is dosed separately by means of a dosing pump (204) between the rolls of the roll laminate coating device (209) and thus created film (209a) is applied onto a foam (212). Both laminate layers (207a, 209a) come together in a double conveyor (211), where a complete diffusive mass transfer between the layers (207a, 209a) is carried out at a certain pressure and speed, to obtain a finished laminate (214) composed of the abrasive layer (213) and the polyurethane foam (212) at the exit from the conveyor (211).

Description

The process of separate application of the activator in the production of flat laminates based on soft polyurethane foam

FIELD OF THE INVENTION

The present invention relates to a new process for the separate application of an activator in the production of flat laminates based on soft polyurethane foam.

Other techniques

The process for the production of laminates on the base of polyurethane sheets is described in the Slovenian patent SI 8611943, and the Slovenian patents SI7712002 and 8110083 are important for the state of the art.

In general, the reaction (I) between polyol and isocyanate in the formation of polyurethane can be represented by the following scheme:

R-OH + R-NCO

2

RNCO — R

POLYOL ISOCIANATE

POLYURETHANE k is the reaction constant.

All polyurethane chemistry is based on this basic reaction i.

It is very important for technological practice at what reaction rate (k) the reaction takes place. The change in the value of the reaction rate constant (k) can be achieved by changing the temperature of the reactants (polyol and isocyanate), and above all by the use of catalysts. The most common catalyst systems are amine or tin based substances. Using these catalysts, the reaction time of the base reaction (I) can be shortened from 10 hours to minutes or seconds. This is well known in the art and has been used in polyurethane technology all the time.

In order to react with a suitable reaction rate (k), the activator is usually dosed into the mixing head so that it only contacts the polyol and isocyanate in the mixing head. The agitator allows convection of the substance as quickly as possible. The total residual resistance to the transfer of matter is only in laminar films at the boundary between the reactant mixture and the activator.

Subsequent transfer of the substance is facilitated by diffusion, which is, however, subtracted from the diffusion properties of the substances that form the reaction system.

Short description of the pictures:

The present invention is described below and shown in the accompanying drawings showing:

Figure 1 schematically shows a known process

Figure 2 schematically shows the process of the present invention

Description of known procedure

The flow of the process currently used is shown schematically in Figure 1.

The polyol (A) contained in the container (101), the isocyanate (B) contained in the container (102) and the activator (C) in the container (103) are dispensed via metering pumps (104) into a mixing vessel (105) ), with a mixer (M) which, by its transverse motion, allows the reactor mixture to be sprayed (106) onto an abrasive layer (109) to be laminated with a soft polyurethane foam (108). Thus, all materials enter the double conveyor (107), which compresses the materials and thus causes overpressure and enables their interconnection (lamination) during the passage through them. Laminate (110) is derived from the double conveyor.

In this process, it is very important that no reaction occurs between the reactants in the mixing head (105). From the mixing head, the reactant mixture flows through special spray nozzles onto the abrasive layer (109) or soft polyurethane foam (108).

The process is construction and technologically demanding. It uses basic reactants, which are very expensive and the technology itself requires very expensive ecological techniques to achieve suitable ecological working conditions.

Description of the invention

We have found that in a technologically simple way, we can make all kinds of, even very thin films, which can serve to homogeneously bond the two materials.

DETAILED DESCRIPTION OF THE INVENTION

The process of the present invention is shown in Figure 2 and is carried out such that the polyol (A ') from the vessel (201) and the isocyanate (B ¹ ), from the vessel (202) and the activator (C ¹ ) from the vessel (203), If all three reactants differ from the reactants in Figure 1 in chemical structure (which will be explained later), they are cheaper and more environmentally friendly, dosed via pumps (204).

The polyol (A ') from the container (201) and the isocyanate (B') are dosed from the container (202) into the mixing vessel (205), and the activator (C) from the container (203) is dosed to a roller laminar application device (209) .

From the mixing vessel (205), an inactivated mixture of polyol and isocyanate is dispensed via a metering pump (206) to a roller application device (207). It continuously applies the reactant mixture in the form of a laminar film (207a) to the abrasive material (213). The activator (C '), which is preferably an eco-friendly solution of urea in water, is dosed via a metering pump (204) to a roller application device (209), a laminar film of urea (209a) located on the foam (212) is provided during transport through a double conveyor (211) joining both materials into a homogeneous laminate (214).

The process of the present invention can be illustrated by the following example, with reference to the accompanying Figure 2.

Example:

From the container (201), a polyol component (A ¹ ), preferably an adipic acid and diethylene glycol-based polyester, is dosed via a metering pump (204) to a mixing vessel {205). At the same time, an isocyanate component (B '), preferably diphenylmethane 4,4 diisocyanate, in the ratio of 100 to 10 parts by weight of polyol {A') and 100 to 10 parts by weight of isocyanate (B ') is dosed from the container (202). Mixer (N) achieves the homogeneity of this mixture.

At the same time, an activator (C '), preferably urea (carbonic acid diamide), is dosed from the container (203) via a metering pump (204) between the cylinders of the roller laminar application device (209). The resulting urea film (209a) is applied to foam (212). The two laminar layers (207a, 209a) are combined in a double conveyor (211), at a specific pressure of 5 χ 10 ² to 50. 10 ² Pa.

The activator diffuses into a mixture of polyol and isocyanate and a chemical reaction (I) is initiated.

As the surface coated with the activator and the layer of the inactive system fit closely together, under the defined pressure, a complete diffusive transfer of matter between the layers occurs.

The composition is run at a speed of 1 m / s to 10 m / s into a double conveyor (211). At the end of the conveyor, a finished laminate (214) consisting of a soft abrasive layer (213) and a polyurethane foam (212) can be removed.

Various obvious embodiments of the process of the present invention will also be apparent to those skilled in the art, but are also encompassed by the present invention.

Claims (1)

Patent claims The process of separating the activator in the production of flat laminates based on soft polyurethane foam, characterized in that the polyol component (A ¹ ) and the isocyanate component (B ') / in a ratio of 100 to 10 parts by weight of polyol (A') and 100 up to 10 parts by weight of isocyanate (B ') in container ¢ 205), where the mixer (N) achieves homogeneity of the mixture of components (A', B '), which is applied to the roller application device (207) via a metering pump (206). , which continuously applies the reactant mixture in the form of a laminar film (207a) to the abrasive material (213) and the activator (C '} is dosed via a metering pump (204) between the cylinders of the roller laminar application device (209} and the resulting film (209a) ) is applied to foam (212), where the two laminar layers (207a, 209a) merge in a double conveyor (211) at a specific pressure in 5 χ 10 ² to 50. 10 ² Pa, at a speed of 1 m / s to 10 m / s, where complete diffusive transfer of matter occurs between the layer of the inactive system <207a) i n a layer of activator (209a), so that at the outlet of the conveyor (211), a finished laminate (214) is formed, consisting of an abrasive layer (213) and a polyurethane foam (212). The process according to claim 1, characterized in that component (A ') is preferably a polyester of adipic acids and diethylene glycol, that component (B') is preferably di-phenetic and that the activator (C ¹ ) is preferably ureic acid). that the polyol base is also zocyanate 4,4-diisocyanate (diamide