DE2311471A1 - PROCESS FOR GLUING INORGANIC FIBERS - Google Patents

Description

Method for gluing inorganic fibers

The invention relates to a method for gluing inorganic fibers and wet felted fibers produced therefrom Materials·

Inorganic fibers, such as mineral wool, have long been used to manufacture materials such as ceiling tiles. For this purpose, the inorganic fibers must be glued to make the finished product water-resistant or make it waterproof. The traditional methods of gluing these products, for example, involve rosin and / or wax emulsions added to the fiber slurry These sizing agents are ineffective unless they are precipitated from the slurry by the addition of alum «These However, precipitation can only occur if the slurry is acidic and preferably has a pH between about 4.7 and 5.5. In order to achieve such a pH value, an acid such as sulfuric acid must be added to most inorganic fibers be as the slurry of the inorganic pastes as such reacts alkaline · Although the alum is a sehwaeh-I acid salt, its effect is not sufficient to j to achieve a usable gluing. For this reason, not only must alum be added to j, but also acid, where-I considerably increases the cost of the manufacturing process.

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jFurthermore, many are made of inorganic fibers jItems require fillers such as calcium carbonate or borax. However, these fillers have an adverse effect on the sizing agent composed of rosin or wax yes, which is probably due to their alkaline nature! Furthermore, by acidifying the slurry through ' '' Addition of alum or acid will impair the properties of certain inorganic fibers, such as mineral wool, yes and no. This deterioration manifests itself in a reduced ! Strength of the finished item.

In the paper industry, the problem associated with the addition of alum was solved by using a cationic wax; Dissolved asphalt emulsion. This emulsion is naturally attracted to the negatively charged paper so that no change in slurry pH or addition of alum is required, examples of this process are given in U.S. Patent No. 2,954,313. A cationic wax-asphalt emulsion added to inorganic fibers, such as mineral wool, is, however, ineffective as such as a sizing agent, since the inorganic fibers are positively charged. Other wax-asphalt emulsions have been used to make products water-resistant, but in completely different areas of technology. An example of this is the use of a wax / asphalt mixture emulsified by a protein dispersant to make plasterboard wall panels water-resistant. In the production of such plates, the emulsion becomes the; ! Gypsum slurry before it is poured between cover plates ■ added, as for example in the USA patent no.; 2,432,963. _;

The invention relates to a method for gluing inorganic; niche fibers and the product made from them. At the he; inventive method does not need added or alum the pH of the slurry to be changed. In the inventive Process is a non-cationic wax-asphalt emulsion for gluing inorganic fiber materials

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lien uses · This non-cationic Waehs asphalt emulsion is applied to the inorganic fibers before the slurry is formed added to a product. An application of alum is not necessary here and the emulsion adheres to the Slurry without the need for precipitation and without the need to acidify the slurry.

The object of the invention is therefore to create a method for gluing inorganic fibers in which none Precipitants or acids are required.

The invention also provides a method for gluing i of inorganic fibers in which the properties of the j fibers are not impaired · j

The production costs in the process according to the invention ' are lower than with the known processes due to the elimination of process steps and expensive reagents

The method according to the invention can be carried out even under strongly alkaline conditions.

The invention also provides a wet felted inorganic fibrous object on which a non-Cyclonic Sizing agent adheres with the solids of the sizing agent no more than about 1 # of the solids of the Subject matter.

The invention will now be further explained with reference to the following description:

In the process according to the invention, a non-cationic Wax-asphalt emulsion used to glue inorganic fibers without the addition of a precipitant is required; the process according to the invention can itself be carried out in an alkaline medium.

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Inorganic fibers that can be used in any way are mineral wool ^! Glass wool, rock wool and ceramic fibers, which usually have no positive charge. The invention is explained in the following on the basis of ceiling panels and molded panels made of mineral wool, but is in no way limited to the gluing of mineral wool. Further, the final product made from the slurry can be any arbitrary item and contain a variety of fillers such as clay and even alkaline additives such as borax.

; Whereas the inventive method as Verleimungs-ίmittel used wax-asphalt emulsion is that described in USA-\ Patent No., 2,432,963 wax-asphalt emulsifier ¹ sion very similar. It consists of asphalt and raw flake paraffin that is emulsified by casein. Only the amount of casein is critical and should be between about 6.0 and 7.0 percent by weight of the total emulsion in order to achieve a useful viscosity. Preferably the particle size of the emulsion should not exceed about 4 microns. A typical composition is given below:

Asphalt 40.0 wt., # Raw paraffin flakes 7 * 5 Casein emulsifier 6.5

Water 46.0

It has been found that this emulsion is not cationic, but rather anionic. The anionic charge of the emulsion was ^; determined by a cataphoric device with which: the migration of the emulsion particles in the electric field can be observed.

This emulsion was diluted so that its solids content was no more than about 1 percent by weight of the slurry. The emulsion then became the inorganic fiber-I slurry added to the mixing tank of the Fourdrinier machine

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give »spell the slurry was formed on the screen I and in a conventional way to boards, tiles and others ; Construction and / or insulation materials processed. The emulsion adheres to the inorganic fibers due to the physical Mechanism of ion attraction, whereby the negative charge in the emulsion adheres to the positively charged inorganic Fibers causes. Particularly noteworthy is »that no Alum or some other precipitating agent or acid must be added in order to reduce the alkaline state of the surface to change slurry. In the case of mineral wool slurries, the pH value is more or less during the entire shaping process of the ceiling tile is maintained at about 8.0

The invention is based on the following examples ER- ^one explained:

In Table 1, for example, two samples of a mineral wool ceiling tile are compared: Sample A was glued with a customary wax and alum as a precipitating agent and sample B was glued exclusively with the wax-asphalt emulsion according to the invention. The percentage Wasseradsorp- ¹ tion was found by determining the weight gain, which at the same sample thickness, and an area of 19.4 cm

'(3 inches ²⁾ (1 inch) and a temperature occurred in the course of 2 hours at a pressure of supernatant water of 2.54 cm by 27 ° 0 (80 ⁰ F). The percentages of the solids relate to the weight.

ί Tabel . 409837 / 1 Sample A 0 5 59 Sample B Component or characteristic 15..0Jl 15.0 * i Power gel according to the ÜSA patent document no, 3 379 608 IO.O36 10.0 * I.
j Perlite 63.0 * 64.0 * ! Mineral wool UO * - - i wax 1.0 * - - i
i alum 1.0 * '. Wax and asphalt emulsion 9.5 * 8.7 * f Water absorption

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read the above experiment shows that the invention Gluing when producing a ceiling panel at least to form an equally water-resistant product as in the known processes leads. -

In the following table 2 the properties of her-! conventional shell boards made of mineral wool shown, ■ were glued according to the inventive method and to ', where "Rasorite 65", an anhydrous sodium borate of the United \ States Borax, in an amount of about 2 weight percent to; Purpose of fire resistance had been added. Five samples were made, each containing a different percentage of wax-asphalt emulsion. This should! It can be determined whether the water resistance increases as the amount of the emulsion is increased. The absorption was like ^; already described measured.

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', Table 2 j

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; ^ Solids on wax-asphalt % absorption j i emulsion for gluing the!

I shell boards ί

0.5 16.5

1.0 12.7

1.5 12.3

2.0 13 · 2

3.0 12.8

The absorbance for the last four samples was within the Error limits practically the same. It is therefore obvious that with an emulsion addition of more than 1., Qj6 practically no Increase in effectiveness occurred.

According to the invention, other types of wax-asphalt emulsions can also be used can be used in the same way, provided that they are either nonionic or anionic and therefore not of the positively charged inorganic fibers are repelled.

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Claims (7)

Claims (^ / Method for gluing inorganic fibers without Change in the pH of the fibers, characterized in that a non-cationic wax-asphalt emulsion into a slurry the fibrous materials gate admits their shaping. 2. The method according to claim 1, characterized in that the emulsion of asphalt, wax, a casein emulsifier and Water exists. 3. The method according to claim 1, characterized in that the amount of emulsion is not more than 1 percent by weight of the total weight the solids of the molded product is. 4. Method of gluing an alkaline slurry of inorganic fibers, characterized in that a non-cationic wax-asphalt emulsion is added to the slurry is added and this emulsion is allowed to adhere to the fibers without changing the pH of the slurry. 5 «The method according to claim 4, characterized in that the emulsion of asphalt, wax, a casein emulsifier and water consists. 6. The method according to claim 4, characterized in that the amount of emulsion is not more than 1 percent by weight of the total weight the solids of the formed fibers is. 7. Wet felted object, consisting of inorganic fibrous materials, a filler and a non-cationic adhering to the fibrous materials and the filler Wax-asphalt locking agent, with the solid content of the sizing agent is no more than about 1 percent by weight of the weight of the formed fibers. 409837/0559