FI91786C - Wallpaper - Google Patents

Description

91786

The invention relates to a wallpaper comprising a coating layer comprising a latex binder and a pigment on top of a base paper, having a surface coating comprising a pigment and a latex binder, the dry matter of the surface coating being at least 20 g / m 2. .

Polyvinyl chloride (PVC) is now commonly used as a coating in wallpapers. This material has been used as a coating mainly due to its protective effect, such as good resistance to moisture, grease and mechanical stress.

However, the use of PVC in bales has 20 disadvantages. Eras such a disadvantage is the waste problem, which is due on the one hand to the recycling problems of the used wallpaper and on the other hand to the waste from the PVC baling process itself. In addition, when burning, PVC generates toxic substances, such as hydrochloric acid, which impairs the fire safety of the wallpaper.

German Patent 2501684 discloses a wallpaper bale coating in which the coating contains an aqueous styrene-butadiene latex as a binder and 30 pigments, which may be insoluble starch or a mixture of calcium carbonate and calcium silicate. The amount of such baling on the base board is usually 8-15 g / m2. As a disadvantage of the baling containing only the inorganic pigment, it has been mentioned in this publication 35 that it is too glossy, rough and unsatisfactory after calendering, in addition to which the abrasion resistance is substantially reduced when roughened.

• · 2 91786

British Patent Application Publication No. 2201613 discloses a wallpaper baler comprising a water-based acrylic or vinyl acetate-based binder together with aluminum hydroxide and possibly also an inorganic baling pigment as a binder. The typical coating composition shown in the examples contains 100 parts of aluminum hydroxide per 100 parts of binder. The possibility of using mineral fillers is only presented in the description.

10

German Offenlegungsschrift 1771129 discloses a wallpaper baling composition which contains an aqueous binder and water glass and barium sulphate as inorganic components. A large amount of water glass causes 15 unwanted variations. The large amount of water-soluble water glass also does not make the wallpaper suitable for printing with water-based inks.

The object of the invention is to provide a baled wallpaper which can replace PVC baled wallpapers and which at the same time has good matte, good ink absorption especially for water-based inks, good abrasion resistance, si leys and gravure printing and which is very 2 5 cold rollable. To achieve this purpose, the wallpaper according to the invention is mainly characterized in that the baling layer has a surface coating containing 100 parts of water-insoluble pigment per 30-70 parts, preferably 40-65 parts of latex binder, and an inorganic water-insoluble mineral pigment of 95%. from the roar of the pigment. Due to the suitable latex binder and the inorganic water-insoluble mineral pigment, as well as the high basis weight of the bale, it has surprisingly been possible to obtain a wallpaper which does not differ externally from the PVC bale wallpaper. but which is more environmentally friendly in terms of manufacturing, manufacturing waste and post-use disposal, as well as fire safety. However, the properties of the wallpaper are not inferior to those of PVC baled wallpaper, and in some respects they were even better.

5

According to a preferred embodiment, the proportion of water-insoluble pigment and latex binder in the dry mass of the surface coating is more than 95% by weight, preferably more than 98% by weight.

10

In addition, the bale layer may provide a pre-coating layer containing a latex binder and a pigment between the surface bale and the base paper, containing 100 parts of water-insoluble pigment per at least 8 parts, preferably 10 to 25 parts of latex binder. The pre-coating layer may consist of two pre-coating layers applied in different stages. The pre-baling layer provides good smoothness before the surface baling and has a volume of at least 20 5 g / m 2, preferably 10-25 g / m 2.

According to a preferred embodiment, the surface coating pigment feeds both magnesium silicate (talc) and calcium carbonate, and the ratio of the amounts of magnesium silicate to calcium carbonate can then vary from 3: 1 to 1: 1. These pigments provide a good matte surface, in addition to which the use of calcium carbonate can reduce the wetting agent required by the talc dispersible shell, which would make the bale 30 too hydrophilic.

The invention will now be described in more detail with reference to the accompanying drawing and to various baling compositions for making the wallpaper according to the invention.

35 In the drawings. Figure 1 shows a cross-section of a wallpaper according to the invention, and Figure 2 shows a cross-section of another wallpaper according to the invention.

5 In the following description, substances are always given in terms of dry matter, unless otherwise stated.

Figure 1 shows a coating layer 2 applied to the base paper 1. The coating layer has a surface coating 10 of PP, which contains 100 parts of water-insoluble pigment per 30 to 70 parts, preferably 40 to 65 parts of latex binder. Inorganic water-insoluble mineral pigment is present in more than 95% of the pigment area. The amount of surface coating PP is at least 15 20 g / m2 dry.

The total amount of coating layer is at least 30 g / m 2 dry, and most preferably it is between 30-65 g / m 2. In this case, it can be formed either exclusively in one step 20 from the bale layer layer 2 applied to the bale of the base paper 1. However, as in Fig. 2, the bale layer can consist of the above surface bale PP and the pre-bale layer EP applied to the bale of the base paper 1 before the surface bale. The amount 25 of the surface coating PP can then vary between 20 and 40 g / m 2, and the amount of the prepackage layer EP is at least 5 g / m 2, preferably 10 to 25 g / m 2. The amount of latex binder in the pre-coating layer may be lower than in the surface coating layer PP and may then vary between 10 and 25 parts per 100 to 100 parts per pigment of the pre-coating layer.

In Fig. 2, it is further illustrated by broken lines that the pre-baling layer EP can also consist of a layer applied in two different stages, which is denoted by the references EP1 and EP2. The composition of these layers is the same as mentioned above and their. the amount is such that the pre-baling layer EP

the total amount becomes the above.

Suitable for the latex binder of the surface coating of the coating layer are all water-based solvent-free latexes which are generally used in the wallpaper coatings. homo- or copolymer latexes, e.g. polyvinyl acetate homopolymer, polyvinyl acetate-acrylate copolymer, ethylene-vinyl acetate copolymer, styrene-acrylate copolymer-full acrylate and styrene-butadiene latexes.

Particularly well suited for use in the invention are polyvinyl acetate-acrylate copolymer, ethylene-vinyl acetate copolymer (PVAC and EVAC) and full acrylate latexes, and styrene-butadiene-styrene, which is readily variable over time, is less suitable for use. Suitable inorganic water-insoluble mineral pigments are, in turn, all pigments commonly used in wallpaper piles, such as kaolins, calcium carbonates, calcium sulphate or gypsum, magnesium-20 silicates or talc, aluminosilicates, titanium dioxide, barium dioxide, barium dioxide, barium A good mixture of inorganic mineral-based pigments has proven to be a mixture of magnesium silicate and calcium carbonate, which is particularly well suited for use in the baling paste used to make the wallpaper according to the invention. The dispersibility of talc, i.e. magnesium silicate, in the latex dispersion can then be improved by means of calcium carbonate and special dispersibility-increasing wetting agents can be reduced, which would make the finished pSS coating too hydrophilic. The calcium carbonate used is then preferably ground rather than precipitated.

35 As other water-insoluble pigments, which account for the proportion of pigment in the surface coating. less than 5% by weight, can be used e.g. in synthetic pigments.

6,91786

In the preparation of the baler, the coating paste forming the PP of the surface baler may additionally contain the flame retardants naturally used in wallpaper bales, such as aluminum hydroxide, elastic blowing agents, hardening agents, hardeners and optical brighteners, as well as other excipients such as dispersants. the proportion of dry mass of the surface coating is generally less than 5%, preferably less than 2%. Generally, these substances are present in less than 2 parts per 100 parts of water-insoluble pigment.

15 All latexes, pigments and other substances suitable for the above-mentioned surface coatings can also be used in the pre-coating layer.

As the base paper 1, any paper 20 with suitable surface properties can be used. The basis weight of the base paper can be, for example, 90-120 g / m2. When using pre-baling layers, more mechanical pulp can be used on the surface to be baled than when using a single baling layer.

25: In the production of the wallpaper according to the invention, the bale coating layer can be applied by bale coating methods known per se, such as blade, air brush, rod and roll coating methods. In addition, it is possible to form the pre-baling layer EP already on a paper machine by one of the above-mentioned methods and the surface baling PP by some off-machine method, e.g. by air brush, blade, reverse roll, die or screen printing method.

35

The following are specific recipes for making a wallpaper coating layer according to the invention. Måarat • · recipes contain dry matter.

7 91786

Recipe 1. So-called normal pre-coating (for terra coating)

Intended use Chemical composition

Pigment Calcium carbonate 100.0 parts

Dispersant Polyacrylic acid salt 0.3 parts

Defoamer Vegetable oil and fatty acid esters 0.1 parts

Viscosity excipient Carboxymethylcellulose 0.3 parts

Acrylic ester 0.5 parts

Binder PVAC acrylate 12.0 parts

Kovetin_tfelandnformaldehvdihartsi_0,4 parts - dry matter content of the baling to be applied 58 - 67%

- viscosity 600 - 1500 iriPa.s / 100 r / min / 20 ° C

- bale size 5-25 g / m2 dry

Recipe 2. So-called normal pre-baling (for airbrush coating)

Intended use Chemical composition

Pigment 1 Magnesium silicate 30.0 parts

Pigment 2 Calcium carbonate 60.0 parts

Pigment 3 10.0 parts of titanium oxide

Dispersant Ammonium salt of polycarboxylic acid 0.3 parts

Defoamer Vegetable oil and fatty acid esters 0.1 parts

Viscosity preservative Acrylic ester 0.3 parts: Binder EVAC dispersion 20.0 parts

Hardener_Aircnonium zirconium carbonate_0.6 parts - dry matter content 55 - 65%

- viscosity 50 - 300 mPa.s / 100 r / min / 20 ° C

- baling weight 5-25 g / m2 when dry «t --------- --- ΤΓ“ 91786 8

Recipe 3. New PVC replacement surface coating

Intended use Chemical composition

Pigment 1 Magnesium silicate 75.0 parts

Pigment 2 Calcium carbonate 25.0 parts

Dispersant Polyacrylic acid salt 0.3 parts

Viscosity excipient Acrylic ester 0.4 parts

Binder 1 PVAC acrylate latex 45.0 parts

Binder 2 Polyvinyl alcohol 5.0 parts

Hardener_Melaminfomaldehyde resin_0.6 parts - dry matter content 55 - 65%

- viscosity 50 - 300 mPa.s / 100 r / min / 20 ° C

- bale size 20 - 50 g / m2 when dry

Recipe 4. New PVC replacement surface coating (for air brush coating)

Intended use Chemical composition

Pigment 1 Magnesium silicate 67.5 parts

Pigment 2 Calcium carbonate 22.5 parts

Pigment 3 Titanium dioxide 10.0 parts

Dispersant Sodium salt of polycarboxylic acid 0.35 parts

Defoamer Vegetable oil and fatty acid esters 0.1 parts

Binder_EVRC-latex_55.0 parts - dry matter content 55 - 65%

- viscosity 50 - 300 mPa.s / 100 r / min / 20 ° C

- baling weight 20 - 50 g / m2 dry 9 91786

Recipe 5. New PVC replacement surface coating (tera-, Reverse

Roll, nozzle and s i Ikipa inomenmetelmiIle)

Intended use Chemical composition

Pigment 1 Magnesium silicate 42.0 parts

Pigment 2 Calcium carbonate 42.0 parts

Pigment 3 Titanium dioxide 12.0 parts

Pigment 4 Sodium aluminosilicate 4.0 parts

Dispersant Polyacrylic 1 acid salt 0.4 parts

Anti-foaming agent White base 0.1 parts

Viscosity excipient Akryy lipo-based polymer dispersion 0.6 parts

Carboxymethylcellulose 0.4 parts

Binder_Akrwlilatex_60.0 parts - dry matter content 55 - 65%

- viscosity 600 - 4000 mPa.s / 100 r / min / 20 ° C

- coating content 30-50 g / m2 dry

The table below shows conceivable combinations of pre-baling and surface baling when preparing the wallpaper according to the invention using one of the aforementioned recipes.

Table Examples of påallys themed in different ways, the figures indicate the dry weight of the pallet in g / m2

Pre-coatings (EP) Surface coatings (PP) - blade - airbrush - airbrush - blade

Replacement (optional) - Reverse Roll tot.

condition - screen weight g / m2 - nozzle (optional)

. EP1 EP2 PP

A 50 50 B 12 40 52 C 20 - 35 55 D 12 10 20 42 E 12 10 40 62 10 91786

The wallpaper according to the invention has been found to have considerably better heat resistance compared to normal wallpapers with PVC bale, for example the decrease in brightness in the experiments has been in the order of ten to 5 percent of the percentages with PVC bale. In addition, the wallpaper according to the invention burns less, and when it burns, it produces less visible smoke and harmful substances than PVC-coated wallpaper. In addition, the wallpaper according to the invention can be embossed, which is not possible with normal PVC-coated wallpapers. In addition, the wallpaper has a better ink absorption, ie there is no beading in the same country as PVC bale-type wallpaper.

15 The presser foot is also better.

The following are the printing tests performed on the wallpaper according to the invention.

The base paper was 98 g / m 2 of a two-ply paper, the layer forming the surface to be coated of which was composed of cellulose and the second layer of mechanical pulp. The paper was baled with pre-baling layers EP1 (12 g / m2) and EP2 (10 g / m2) with baling tea according to recipe 1. The baling was performed as a terrain baling.

A surface coating with a basis weight of 35 g / m 2 was applied to the pre-baling layer in an airbrush baling using a baling according to recipe 4. At that time, the total amount of baling applied to the base paper was 57 g / m2.

A test run was performed on a gravure printing machine designed for printing wallpaper paper, in which both PVC-coated wallpaper and the above-mentioned wallpaper were printed. The weight-35 machine used all six shadow units, i 11 91786, using acrylic dyes dissolved in toluene-methyl ethyl ketone solvents. The speed of the printing machine was 150 m / min and the drying lamp temperature was 105 ° C.

5 The printing press was first printed on wallpaper coated with the most commonly used PVC plastic sol, with a base paper content of 90 g / m2 and a backing volume of 90 g / m2. After this, the wallpaper according to the invention was printed with the same printing presses and under the same conditions. It was noteworthy that no additional yields had to be made on the printing machine when moving from the PVC-coated wallpaper to the one according to the invention.

The wallpaper according to the invention achieved a clearly brighter and more variegated print than the PVC-coated wallpaper. The transfer of copper from the gravure cup to the surface of the wallpaper was also clearly better with the wallpaper according to the invention than with the PVC bale-20 wallpaper.

In the second experiment, the printing was performed with a flexographic printing machine for printing wallpaper. The printed wallpapers were the same as in the previous 25 experiments. The flexographic printing machine had six shadow units, and alcohol-aqueous flexographic printing presses were used as printing machines. The speed of the printing machine was 150 m / min and the temperature was 110 ° C. The wallpaper according to the invention had a clearly brighter presser foot than the presser foot of the PVC wallpaper.

Claims (5)

91786 A wallpaper comprising a coating layer (2) containing a latex binder and a pigment on a base paper (1) with a surface coating (PP) containing a pigment and a latex binder, the amount of the surface coating (PP) being at least 20 g / m 2 dry and the total amount is at least 30 g / m 2 dry, characterized in that the surface-10 bale (PP) contains 100 parts of water-insoluble pigment per 30 to 70 parts, preferably 40 to 65 parts of latex binder, and the inorganic water-insoluble mineral pigment is more than 95% of the pigment content . 15 Wallpaper according to Claim 1, characterized in that the proportion of water-insoluble pigment and latex binder in the dry mass of the surface coating is more than 95% by weight, preferably more than 98% by weight. 20 Wallpaper according to Claim 1 or 2, characterized in that the bale layer (2) comprises a precoat layer (EP) 25 containing a latex binder and a pigment between the surface bale (PP) and the base paper (1), containing at least 8 parts per 100 water-insoluble pigments. parts, preferably 10 to 25 parts of latex binder. Wallpaper according to Claim 3, characterized in that the amount of the precoat layer (EP) is at least 5 g / m 2, preferably 10 to 25 g / m 2. Wallpaper according to one of Claims 1 to 4, characterized in that the inorganic pigment of the surface coating (PP) is applied to both magnesium silicate and calcium carbonate. l · 91786