MXPA99001639A - Support with super-absorbent material, method for the preparation thereof and use - Google Patents

Abstract

The invention relates to a support provided with super-absorbent material to be manufactured by causing suitable monomers to polymerize in the presence of a catalyst in order to obtain a polymer solution, adding a cross-linking agent to the polymer solution to obtain a pasty composition, subsequently applying the composition on or in a support and allowing the applied composition to dry and cross-link in order to obtain the support with the super-absorbent material, wherein microspheres are added to the paste.

Description

SUPPORT WITH SUPERABSORBENT MATERIAL, METHOD FOR THE PREPARATION OF THE SAME AND ITS USE.

Description of the invention The present invention relates to a support provided with a superabsorbent material, to a method for the preparation thereof and to a method for manufacturing the superabsorbent material, in addition to the use of the support in different products. Said superabsorbent material is described in NL-A-1000572. With the "bulky coating" described in this patent application, it is proved that a paste, which has superabsorbent properties, is applied more effectively (ie, with better absorption properties) through a template application technique. When using this printing technique, the paste islets are applied in such a way that after drying and curing, they have a diameter of 200 μ. A second advantage of this form of application is that the release of the coating is prevented. Since the polymer used is very hard, it is not possible to completely coat the surface with it, since the coating, after drying as it is, breaks the substrate. Even after the application of the coating in the form of islands, it will still "break" REF .: 29445 some times. A disadvantage of the application technique, and consequently of the form of coating, is that its application is limited. It is theoretically possible to apply a maximum such that the 200 μ islets are 200 μm apart, and if they are completely (semi) spherical, they should be a maximum of 100 μm in height. Consequently, it will theoretically be the application of a maximum of 70 g / m. This application is however smaller, since the applied coating contains 70% water and the point consequently shrinks. It will not be the ideally semi-spherical applied point, because it is very difficult in practice to apply more than 50 g / m2 (dry state). In the first instance, we saw a possibility of making a softer coating in such a way that after the application it is no longer so hard that the coating "breaks" in the lightest mechanical load. Research has been carried out on two different types of softeners; a softener that is between the polymer and a softener that is "fixed" to the polymers. In addition, the first type of fabric softener, which is not recommended for cable recessing material (due to corrosion of the insulation), has been found not to work, the coating remaining brittle. The object of the invention is to demonstrate the abovementioned disadvantages and to provide for this purpose, a method that is distinguished in that an expanded microspheres are added to the coating. It has been found by chance that, by adding expanded microspheres, not only did the coating become much less hard, but also that these microspheres had a positive effect on the so-called bulking speed (= the absorption time). These two properties discovered by chance, now make possible the application in the total of the surface, of the paste in a number of substrates, at the same time to continue retaining the same properties of absorption. The fact that the absorption properties are improved can be explained by the fact that the coating layer becomes microporous, due to the presence of the microspheres and to the water being rapidly transported through the coating. It can be established experimentally that the addition of 1 to 100%, preferably 10% of microspheres, makes a coating softer and the bulking coating material can, consequently, be applied in a total coating of the surface to the same substrates, which they have been described in the above-mentioned patent application, by means of which the application can be increased (more than 50 g / m2 in the dry state). In this application, "microspheres" means small globules that are filled with gas. By heating, the gas expands and the globules increase in size. The microspheres are known per se and are used for different purposes, such as ink sealers, etc. A known type of microsphere, which is also particularly suitable for use in the invention, are the microspheres of the brand and type Expancel ™ 551 WE. The microsphere wall generally consists of a thermoplastic polymer. For use in the invention, the microspheres may or may not be expanded. The expansion can take place before or during the coating production process. It is noted that, with respect to this date, the best method known by the requested one, to carry out the present invention, is the one that is clear from the present, discovering the invention. Having described the invention as above, the content of the following is claimed as property.

Claims (1)

1. CLAIMS The use of microspheres as softeners and enhancers of the absorption time in a superabsorbent material, characterized in that the material is obtained by causing suitable monomers to polymerize in the presence of a catalyst, in order to obtain a polymer solution, adding an interlacing agent to the polymer solution to obtain a pasty composition, by applying the composition subsequently, on or on a support and allowing the applied composition to dry and interlock, in order to obtain a support with a superabsorbent material. The use according to claim 1, characterized in that the microspheres are expanded at a specific time, before or during the production process of the coating. The use of compression with claim 1 or 2, characterized in that the microspheres are Expancel ™ 551 WE microspheres.