DK144099B - NURSELY SURFACE MATERIAL FOR SETTING UP AS A DANGEROUS Ceiling OR WALL COATING - Google Patents

Description

14409 9 In recent years, the technique of installing free-hanging ceiling tiles in houses has been developed in several ways. The oldest technique consisted in clamping a tissue of e.g. jute, cotton or other available cellulosic fiber and then painted it, usually with a white color. The method has been improved by replacing the fabric with elastic, which is easier to clamp, which can better withstand the housing and which does not need to be painted since it already has a white, dense surface. A further improvement consists in the swelling of these films before the set-up by means of a swelling agent which evaporates after the set-up, whereby the film shrinks and extends by itself. By incorporating glass fibers or other non-combustible fibers 15 into the plastic film, it is obtained that it does not fall down by fire, while retaining its ability to swell in solvent and subsequently shrink to full, despite being mixed with these non-combustible fibers. stretching the solvent evaporation after mounting the ceiling lining 20.

Several attempts have been made to similarly clamp woven fabric of e.g. hunt or cotton after it is first swollen in water. However, all of these attempts have failed for the reason that the fibers in these fabrics, like all natural cellulose fibers, have a very slight longitudinal swelling, whereas the swelling in the transverse direction of the fibers is considerable. Thus, the swelling of the area of the fabric is not required, which is a prerequisite for the application of this method in the setting of ceiling coverings.

However, it has now been found, according to the invention, that the problem can be solved by using a cellulose fiber woven or knitted cellulose fiber material known per se with a low degree of crystallinity relative to the natural cellulose. Such a material has surprisingly proved to work perfectly well for the present purpose. The low longitudinal swelling of fibers of natural or native cellulose is related to the high degree of crystallinity and, to some extent, the crystal type which characterizes the native cellulose, also called Cellulose I. if the amount of amorphous material is thus increased in relation to the native cellulose from which they are made, then these substances can be swollen in water, so that in area 10 they may be about a dozen percent greater. Such an asphyxiated substance can be used in the same way as the aforementioned plastic foils for setting up as ceiling linings in a room, as they shrink themselves when the water (swelling agent) evaporates.

Accordingly, the invention consists in use as a free-hanging ceiling or interior wall covering of a woven or knitted cellulose fiber material as mentioned on the basis of cellulose having a low degree of crystallinity 20 relative to native cellulose (Cellulose II) and consequently good swellability in water both in the longitudinal direction and in their transverse direction, which ceiling or interior wall covering during drying after installation in wet swollen condition is self-tensioning in both longitudinal and transverse directions.

The most common methods for lowering the degree of crystallinity of the cellulose are to treat it with strong bases or other strong electrolytes in aqueous solution or with liquid ammonia, amines or quaternary ammonium compounds and subsequent washing of the reagents or dissolving the cellulose and spinning the fibers thereof. , eg. by the viscose or cuprammonium method, or by regenerating the cellulose from fibers of cellulose derivatives, e.g. acetate cellulose, nitrocellulose and the like.

Other methods include partially substituting the hydroxy groups of the cellulose with e.g. methyl, ethyl, hydroxyethyl, hydroxypropyl, carboxymethyl, aminoethyl or amidoacryl groups and the like.

144099 3

Most of these methods change not only the crystallinity degree of the cellulose but also its crystal structure, and it is transformed into the form commonly called Cellulose II.

5 The difference between the crystal structure of Cellulose I and Cellulose II consists primarily in that a crystal axis of the elemental cells is extended in Cellulose II and that the angle between two crystal axes is simultaneously reduced. Various authors state 10 different values which are compared to the following mean values by Treiber in his book "Die Chemie der Pflanzenzellwand", page 157, (Berlin 1957): Length in Angstrom of the Axes Angle between ab C a and b 15 Cellulose I 8, 10.29 7.83 84 ° 23 '

Cellulose II 8.25 10.3 9.25 61 ° 13 '

The elemental cells in Cellulose II are thus somewhat "looser packed" than in Cellulose I and should therefore have a greater tendency for swelling.

The degree of crystallinity, as a percentage of crystalline material calculated on the full cellulose content of the fibers, varies with different cellulose materials. Different measurement methods also give different results, as can be seen in the following tables:

Philipp, Nelson and Ziifle, in "Textile Research Journal", 17, 585 (1947), give the following values for crystallinity of various cellulose fibers measured by acid hydrolysis: 30 Material Crystallinity%

Ramie 95

Cotton 82-87

Cotton liners 88

Cotton, mercerised under stretch 78 35 Cotton, mercerised without stretch 68

Fortisan ® (saponified acetate cellulose fiber) 83

Cordura® rayon (extra strong) 62

Rayon for textiles 68 U4099 4 P.H. Herman's also &, Messages indicate in "Journal Polymer Sci", 4, 135 ^ 949); 5, 656 (1950); 6, 533 (1951), the following values for crystallinities in cellulose fibers, measured partly by X-ray diagrams and partly by 5 density determinations.

Crystallinity%

By X-ray diagram By density determination Cotton 70 60

Ramie 70 60 10 Sulfite cellulose 65 50

Fortisan® 50 -

Viscose rayon 40 25

It has now been found that in order to achieve sufficient length swelling in the cellulose fibers which will be used for swellable, self-tensioning ceilings, such as those mentioned in the preceding treated cellulose fibers should be used where the crystallinity of the cellulose is more than 5% lower than in the native cellulose from which they are made.

20 It has also been found essential to achieve a large area swelling of the fabrics that one has a low and moderate orientation in the cellulose fibers used. This orientation is produced by the mercerization of cellulose fibers as well as by spinning of dissolved cellulose by stretching the fibers during the process. Thus, in the manufacture of fibers for the present purpose, this stretch should be avoided or kept moderately.

For obtaining special effects, e.g. with regard to burning properties, the cellulose fibers can be mixed with fibers of another material, e.g. mineral fibers. This can be done either by the spinning, so as to spin yarn of mixed fibers, or by the weaving using yarns of different fiber materials in the same fabric.

The fibrous material should be treated with flame retardants before or after weaving, which means that the fabric cannot burn, but only charred when exposed to fire. Examples of such agents are phosphates, phosphites, phosphonium compounds, borates, bromine or chlorine compounds, antimony compounds and the like.

In addition, the substance can be cached with a water-swellable plastic mass, such as e.g. can give the product a denser surface, better flame resistance or other desired properties. The plastic can be applied in the form of a solution, an emulsion or as a foil. These coatings should, as mentioned, be swellable in water so that the plastic layer accompanies the fabric during the swelling of the material.

The following examples show some embodiments of the use according to the invention of the present cellulose fiber materials.

Example 1

A woven cotton fabric is dipped for 5 minutes in an 85 µl hot, 3% sodium hydroxide solution in water. Subsequently, it is immersed for one minute in a 25 ° C hot, 20% solution of sodium hydroxide in water, whereupon it is immediately freed of all liquor by rinsing with water. During the whole process, the cloth is avoided to stretch more than necessary for its transport through the baths.

After further careful washing of all soot residues, impregnate with a solution of 10 parts diamonium orthophosphate and 30 parts urea in 60 parts water. After extruding the excess solution, the fabric is dried for 13 minutes at a temperature of 160 ° C. Then, ester is washed in water and dried. This anti-flame treatment means that the substance can not burn, but is simply charred to a hard ash shell on fire. The fabric is sewn together into pieces of suitable size for ceiling linings using cotton yarns which are similarly flame retardant or with fiberglass yarns. The fabric is then swollen in water and secured to the walls at a suitable height under the ceiling in the room where it is intended to serve as a ceiling covering. It does not need to be stretched for this, but simply hangs loose like a sack. Upon evaporation of the water the substance shrinks and is stretched by itself.

This fabric can be further coated with plastic 5 for a more fireproof product. The following example illustrates one embodiment thereof.

Example 2

Fabric as described in Example 1 is coated on one side with the following paste: 10 8 parts ethyl hydroxyethyl cellulose 7 "triethanolamine 4" triaminotriazine 5 "pentaerythritis 7" ammonium polyphosphate 15 3 "titanium dioxide 0.5" oxaldehyde 2.5 "formic acid 63" water

The ironed surface is sprinkled with 3 cm long 2 20 glass fibers to a weight of 20 g / m and then dried in an oven at 100 ° C. After drying, the cloth is again coated on the same side with the same paste and dried again in the same way.

The fabric produced is cut into pieces of suitable size, wetted in water for maximum swelling and set up as a ceiling covering in the same manner as in Example 1.

The coating applied to the fabric has the properties of producing a strong carbon foam, which is very hard ash on fire. This carbon foam acts heat insulating and thus protects the overlying parts of the building from such intense heating that ignition occurs.

The ethyl hydroxyethyl cellulose is reacted with 35 oxaldehydes to form a water-insoluble form, but is still swellable in water. Therefore, the ceiling can be washed after setup if this is necessary.

144099 7

Example 3

Viscous cellulose staple fibers are made using negligible stretching during the spinning. 95 Parts of these fibers are mixed with 5 parts of aluminum silicate fiber with a fiber diameter of 2.5 µ and carded and spun into a yarn of finesse No. 30. From the yarn, a fabric is woven with 10 threads per minute. cm in both chain and shoots.

This substance is flame retardant treated with ammonium phosphate and urea in the same manner as in Example 1 and can then be used as ceiling covering in the same manner as in Example 1. It can also be coated with plastic pulp as in Example 2.

Here, there is no need to be sprinkled with glass yarns, as the aluminum silicate yarns already embedded in the yarn provide sufficient load-bearing capacity for the fabric under fire, so that this can form a cohesive carbon-foam mineral fiber mat.

Example 4

A 400 denier silk silk yarn made with negligible stretching during spinning is woven together with an equally thick fiberglass yarn to a fabric of 10 threads per minute. cm in both chain and shot direction. The glass yarns make up every tenth thread in the chain as well as the shot direction. The fabric is flame retardant with ammonium phosphate and urea in the same manner as in Example 1. It can then be used as a swellable ceiling covering. In addition, it can be coated with plastic pulp in the same manner as in Example 3 before being set up as an anti-inflammatory ceiling lining. As the shrinkage is greater than the swelling, these fiberglass yarns, which neither participate in swelling nor shrinkage, do not prevent the use of the tablecloth for self-tensioning ceiling cladding. The shrinkage effect can be increased by already wetting the viscose silk yarn during the weaving. The glass yarns, when shrinking according to the configuration of the ceiling covering, give a certain ripple effect which can be utilized deco-