WO2011026671A1

WO2011026671A1 - Wash-resistant wall coverings

Info

Publication number: WO2011026671A1
Application number: PCT/EP2010/059688
Authority: WO
Inventors: Frank Weinelt; Michael Vetter
Original assignee: Evonik Degussa Gmbh
Priority date: 2009-09-03
Filing date: 2010-07-07
Publication date: 2011-03-10
Also published as: DE102009029153A1

Abstract

The invention relates to a method for producing flexible wall coverings having high dirt repellency, resistance to washing processes and high diffusion openness. The substrate is coated by a polymer dispersion, dried and cured.

Description

Washable wall coverings

The present invention relates to a method for the production of flexible wall coverings with high soil repellency, resistance to washing-off operations and high diffusion openness.

Wall coverings, such as wallpapers, which are predominantly made of paper or predominantly of paper-containing nonwoven on the basis of natural and synthetic fibers and which are possibly combined with suede (flock), plastic foam, plastic coatings, cork, textiles, fibers, leather, Veneer, rice paper, metallized, natural materials or printing, such as gravure, high-pressure, flexographic, glue, screen or digital printing, or in addition are three-dimensionally deformed, such as By embossing or suede, which form outer surface, are susceptible to staining and mechanical stress. Examples of wall coverings are paper wall coverings, vinyl wallcoverings on paper or on woven or nonwoven backing, cork wall cladding, edging, relief wall cladding, chemically expanded profiled wall cladding, velor wall cladding and wall cladding made of natural materials. The wallpaper industry assumes a mean useful life of three to four years. Construction and construction are adapted. However, the realistic average useful lives of laid wallpaper are around eight years. An extension of the durability of a wallpaper without having to do a great deal of technical effort is thus desirable and desirable from the point of view of sustainable management and a careful handling of raw material resource and energy. To improve the durability, the aspects of dirt repellence, stain protection and resistance to washing-up are used.

There are some proposals in the literature for the dirt-repellent finishing of wall coverings. In the utility model DE 1901420 U it is proposed to provide non-woven on laminated felt with an equipment of organic fluorine compounds for a water and dirt repellent equipment. DE 3025736 discloses to impregnate threads and fibers of a fabric with transparent, flexible plastic. The resulting surfaces are firmly closed, smooth surfaces, which are formed from duro- and thermoplastic materials. The coating materials are applied in a basis weight of 120 to 210 g / qm. Disadvantages of this procedure are the high quantities of material used and the closed surfaces, which result in restrictions in the design of the fabrics.

The utility model DE 29613699 U1 discloses a fibrous liquid wallpaper that is breathable and u.a. dirt-repellent additives can be added. The liquid wallpaper is painted on the wall. Disadvantage of this structure, the high demand for dirt-repellent additives and the low efficiency due to the intensive interaction with all other components of the described material, especially if, as described must be applied several times.

DE 601 17862, on the use of fluorochemical urethane compositions, and DE 60132818, on the use of fluorochemical ester oligomer compositions, disclose coating materials for finishing hard substrates and fibrous substrates. The applied layer thicknesses are several μιτι to about 20 μιτι or more, which are therefore usually expensive and change the surface appearance and feel at high layer thicknesses.

The technical solutions described above have in common that stain-resistant properties are particularly important on fibrous substrates, if they are considered as wall coverings. Due to the technical structure of these materials, larger quantities of equipment are necessary. Even with highly efficient systems, as described in DE 601 17862 and DE 60132818, several μιτι thick layers are necessary to achieve the desired effects. The production costs for such equipped wall coverings are significantly increased. The use of small amounts leads to low effects and low efficiency. The fluorine-containing silanes disclosed in DE 69832784 are described as dirt-repellent and as anti-fingerprinting agents. They are used as impregnation and have the disadvantage of requiring the use of perfluorinated solvents. Such impregnations also do not increase the wash-off and abrasion resistance of sensitive substrates and, therefore, are more useful on hard substrates and leather.

The fluorine-containing polymers described in DE 68904479 are combined for a dirt-repellent finish with auxiliaries such as wax, starch, casein or resin formulations. Disadvantageously, these aids lead to a significant reduction in dirt repellency. Without these aids, the permanence on the substrate is not given.

Although the use of fluorocarbon-containing polymers is known in the state of the art for producing good water and oil removal on textiles made of natural fibers and synthetic fibers and hard surfaces, the improvements found are not transferable to wall coverings of the type described. This results from the application on the finished product in the last step, and from the requirement to produce very thin coatings with high efficiency.

Thus, the object of the present invention, in the production of dirt-repellent, compared to the non-finished substrate in the washability or abrasion resistance improved and not impaired in the diffusion openness wall coverings, as well as the provision of the wall coverings themselves. In addition, the inventive method to simple, inexpensive substrates be applicable.

This object is achieved by a method for producing a flexible wall covering comprising the steps:

1) providing a substrate,

2) applying at least one organic polymer dispersion at least on the visible side of the substrate, and then 3) drying the BeSchichtung obtained after step 2) at an ambient temperature T1 of 1 10 ° C to 220 ° C for a period t1 of 10 sec to 10 min and

subsequent hardening at a surface temperature T2 of 150 ° C to 200 ° C for a period t2 of 10 sec to 10 min.

The subject of the present invention is therefore a method for producing a flexible wall covering comprising the steps:

1) providing a substrate,

2) application of at least one organic polymer dispersion on the visible side of the substrate, and subsequently

3) drying of the coating obtained after step 2) at an ambient temperature T1 of 1 10 ° C to 220 ° C for a period t1 of 10 sec to 10 min and

The method has the advantage that wall coverings, for example wallpapers, which are predominantly made of paper or predominantly of paper-containing nonwoven based on natural and synthetic fibers and cellulose and which are possibly combined with velor (flock), plastic foam, plastic coatings, cork , Textiles, fibers, leather, veneer, rice paper, metallized, natural materials or printing, such as gravure, high pressure, Flexodmck, glue printing, screen printing or digital printing, or in addition are three-dimensionally deformed, such as by embossing or velor application, to be finished.

Thus, the method according to the invention is not limited to substrates which the person skilled in the art usually selects for the purpose of use, but can in particular be carried out with any substrate of the prior art. Substrates which per se are not or only slightly resistant to moisture and / or frequent contact, which are easily polluted, or which soon change adversely as a result of the ambient climate or by handling and use, are modified by the invention. The process according to the invention is optically and haptically finished, as well as made longer lasting and less sensitive to contact and dirt.

A pretreatment of individual components of the substrate is not necessary. The order of the organic polymer is flat in the simplest form, wherein the Abwaschpermanenz is increased by the thermal curing. The coatings are characterized by layer thicknesses <2 μm, whereby the optical and haptic changes of the surface can be kept low.

The advantage of the coating obtained according to step 2) of the process according to the invention consists in the increase of the mechanical resistance to washing and possibly scrubbing in conjunction with water and cleaning agents.

The functions of the subsequent coating are:

, Solidification of the composite material

• Good stain resistance, stain repellency and washability

• Good cleaning ability

, Increase of washing resistance or abrasion resistance

, Preservation of the diffusion-openness of the substrate

The process of the present invention is not limited to any specific substrates. The substrates can be both open-pored and closed-pore. In particular, the substrate is flexible in step 1). In a preferred embodiment, the substrate of step 1) is a surface filled with excipients material, a knitted fabric, a woven fabric, a braid, a film and / or a sheet structure for optical design three-dimensionally structured and coated (such as color overprint, metallization, mineral coatings).

Preferably, the substrate in step 1) under the drying conditions of step 3) is substantially thermally stable. The materials which are predominantly made of paper or predominantly of paper-containing nonwoven on the basis of natural and synthetic fibers and cellulose and which are optionally combined with suede (flock), plastic foam, plastic coatings, cork, textiles, fibers, leather , Veneer, rice paper, metallized, natural materials or printing, such as gravure, flexographic, glue, screen or digital printing, or in addition are three-dimensionally deformed, such as by embossing or suede, are processed in the following manner, which form the outer surface the visible side coated with an organic polymer dispersion, dried and cured. It may be followed by one or more coatings with the same or a different organic polymer dispersion. Advantageously, dispersions are aqueous.

Preferably, the drying and curing of the composition in step 3) is carried out by heating to a temperature T1 = T2 of 140 ° C to 200 ° C in one step. In a further preferred embodiment, the mixture is dried and cured at a temperature T1 = T2 of 150 to 190 ° C during the period of 10 seconds to 10 minutes.

The drying and curing in step 3) can be carried out by means of heated air, hot air or electrically generated heat. Also, radiation curing may follow, for example, by infrared or microwave irradiation.

Depending on the requirement profile of the end application to be fulfilled, a further coating can be carried out in accordance with step 2). The function of this coating is essentially the formation of a resistant composite material.

The repetition of steps 2) and 3) can take place as often as desired. This approach advantageously increases the resistance of the building material, since after the repetition of 2) and 3) several intimately and yet not rigidly interconnected thin layers are obtained. The outer coating is preferably an organic polymer dispersion containing fluorocarbons to improve water and oil repellency, as well as soil repellency, and to be applied to the visible side of the wall covering.

Organic polymer dispersions, on the basis of which first and preferably further coatings are carried out according to the invention, may be polyacrylates, polymethacrylates, polyurethanes, polyesters or combinations or copolymers / cocondensates, optionally with the use of further vinyl monomers. Optionally, the polymer dispersions may contain fluorocarbons containing fluoroalkyl groups CF ₃ C _n F _2n with n = 1 ..17 preferably n = 3..1 1 or ether chains of the structures CF ₃ CFR "-O-CF ₂ CFR"] _p with p = 0..10 and R "= F, Cl, CF _3. The fluorinated chains particularly advantageously form side chains which are additionally combined with non-fluorinated hydrocarbon side chains The polymer dispersions may contain crosslinkers (for example blocked isocyanates) The polymer dispersions may preferably be cationically modified and booster and extender, and often crosslinkers can act as boosters.

The average molecular weight of the polymers is preferably at least 15,000 g / mol.

The wet application rate of polymer dispersion is 10 to 600 g / m 2 at solids use concentrations of 0.1 to 120 g / L, preferably 3 to 90 g / L in the liquor.

In the case of using fluorocarbon dispersions, the order of organically bound fluorine is 0.01 to 23 g / m 2, preferably 0.05 to 13 g / m 2. The layer thicknesses produced after drying are at most 2 μιτι.

It is particularly preferred to use aqueous polymer dispersions. These dispersions may be self-emulsifying or stabilized with emulsifiers.

It is particularly advantageous when polymer dispersions are used which have a high washing permanence. In addition, the polymer dispersions in a known manner aids such as emulsifiers, defoamers, fixing resins, Fungicides, antistatic agents or catalysts can be added for efficient use.

The order of the polymer dispersions can be done by knife coating, spraying, rollercoating, dipping, padding, flooding, foam application, by brushing or in a combination of the aforementioned techniques in a conventional manner.

A particularly surprising advantage of the method according to the invention is that wall coverings are obtained in which not only the stain resistance is improved over the prior art, but the washing and scrub resistance is significantly increased.

Furthermore, it is surprising that the wall coverings described with an increase in the washing or abrasion resistance, as well as the better stain resistance, the diffusion resistance for water vapor, contracted to the term water vapor diffusion resistance hardly or not increase.

The water vapor diffusion resistance, also called water vapor equivalent air layer thickness SD, expresses the extent to which a building material hampers the diffusion of water vapor in the sense of its thermally driven propagation. Water vapor diffusion resistances of various materials are related to the water vapor diffusion resistance of air by means of the water vapor diffusion resistance number.

The water vapor diffusion resistance number (symbol μ) of a building material is a dimensionless material characteristic value. This indicates the factor by which the material in question is closer to water vapor than an equally thick, stationary air layer. The larger this material characteristic is, the denser a building material is against water vapor. For air is defined

μ = 1.

The values for μ for the most common building materials are given in DIN EN 12524. Important is the water vapor diffusion resistance factor for the calculation of the vapor diffusion current through components. The vapor diffusion depends on the diffusion resistances of the individual layers.

The determination of the water vapor-equivalent air layer thickness SD, unit meter, is given in the standard DIN 53122-1. The water vapor diffusion resistance is calculated as follows:

μ x thickness (in meters).

The thickness is the thickness of the resting air layer thickness in m, which has the same water vapor diffusion resistance. For example, a 20 cm

thick brick wall a diffusion resistance of

5 x 0.2 m = 1 m

on, meaning that through a 20 cm thick brick wall as much water vapor flows through, as by a 1 m thick, resting air layer.

For example, contrary to popular belief, polystyrene is quite permeable to vapor - comparable to wood, for example. For a 4 cm thick polystyrene plate, the value of SD is about 50 x 0.04 m = 2 m.

For example, for vapor barrier films, the value of SD is between about 0.25 m and 10 m. There are versions of vapor barrier films which are more porous in moist air than in dry air.

Another object of the present invention is therefore also the wall covering, which is obtained by the method according to the invention. The present invention therefore also relates to a wall covering which has a stain resistance of at most 10 and an improvement in the abrasion resistance at 30 strokes compared to the non-finished wallpaper of at least 2 evaluation units.

Preferably, the wall covering according to the invention or inventively obtained an increase of the water vapor equivalent air layer thickness SD compared to the untreated wallpaper by at most 0.3 m, more preferably by at most 0.1 m. The untreated wallpaper is understood as meaning a wallpaper or a substrate on which or at least one step of the process according to the invention has not been carried out.

The inventive method and the wall covering according to the invention will be explained in more detail with reference to the following examples.

example 1

3 g of Fluowet UD, 3 g of Genagen LAB and 50 g of Nuva TTC from Clariant are added to 950 g of water and stirred until homogeneous. With this dispersion, a glue printing wallpaper is coated by knife coating. The wet application is about 50 g / m ² . Subsequently, the coated sample is dried for 60 seconds at 180 ° C and cured. Examination of this material gave the property profile shown in Table 1 as compared to the same unattacked wallpaper:

Table 1 Spot stain resistance is achieved by adding 1 - 3 ml coffee, tea, tomato ketup, mustard, 1% NaOH, 10% citronic acid solution, shower gel "Hair &Body" from Stoko Skincare, grape juice, vegetable oil for one hour and rinsing with Water assessed without further mechanical cleaning Assessment is made by scoring for each test equipment: no visible changes - 0, just noticeable changes in gloss and color - 1, slight changes in gloss and color - 2, strong marks on the surface, the structure of the test surface is largely undamaged - 3, strong marks visible, the structure of the test area has changed or the test substance has penetrated deeply - 4, test area has changed considerably - 5.

The abrasion resistance is assessed in accordance with DIN EN 12956 and DIN EN 259-1 for (high) abrasion resistant surfaces. The assessment takes place in the light box described there.

The assessment is done according to the following scale of values compared to the unclaimed surface: no change - 0; Slight change in gloss - 1, change in luster and slightly in color - 2, visible scuff marks not continuous - 3, continuously visible scuff marks - 4, continuous and highly visible scuff marks, surface slightly damaged - 5 or continuous and highly visible scuff marks, surface badly damaged - 6.

Example 2

3 g of Fluowet UD, 3 g of Genagen LAB and 200 g of Nuva TTC from Clariant are introduced into 800 g of water and stirred until homogeneous. With this dispersion, a glue-printed wallpaper provided with a gold print is coated by knife coating. The wet application is about 50 g / m ² . Subsequently, the coated sample is dried at 180 ° C and cured for 30 seconds at 180 ° C.

Testing of this material gave the property profile shown in Table 2 compared to the same unattacked wallpaper: Unexpedited Wallpaper After example

equipped wallpaper

Stain resistance 1 1 5

Scrub resistance 5 0

30 strokes

Table 2

Example 3

3 g of Fluowet UD, 3 g of Genagen LAB and 100 g of Nuva TTC from Clariant are added to 900 g of water and stirred until homogeneous. With this dispersion, a flocked glue-applied wallpaper is coated by knife coating. The wet application is about 100 g / m ² . Subsequently, the coated sample is dried at 130 ° C and cured for 30 seconds at 180 ° C.

Examination of this material gave the property profile shown in Table 3 as compared to the same unattacked wallpaper:

Table 3

Claims

claims

1 . Method for producing a flexible wall covering, comprising the steps:

1) providing a substrate,

2. The method according to claim 1,

characterized in that

in step 1) the substrate is selected from paper, flock, plastic foam, cork, natural material, textile fibers, or a combination of these materials.

3. The method according to claim 2,

characterized in that

the material or materials are metallised or printed on their surface.

4. The method according to at least one of claims 1 to 3,

characterized in that

in step 2) the last applied polymer dispersion, or, if exactly one polymer dispersion is applied, this dispersion has fluorocarbons.

5. The method according to at least one of claims 1 to 4,

characterized in that

in step 3), a temperature T1 = T2 of 140 ° C to 200 ° C is selected.

6. Flexible wall covering, obtained according to at least one of claims 1 to 5.

7. Flexible wall covering that

a stain resistance of at most 10, and

an improvement in abrasion resistance

at 30 strokes opposite the unequipped wallpaper of

has at least 2 valuation units.