Cementitious adhesive composition

Abstract

A cementitious adhesive composition, in particular a tile adhesive, especially for use in automatic tiling systems, includes 10-70 wt.-% of a hydraulic binder, in particular cement, 20-90 wt.-% of aggregates, in particular sand and/or calcium carbonate, and 0.01-5 wt.-% cellulose ether.

Claims

1. Method for the application of a processable composition, comprising the steps of producing a processable composition comprising a cementitious adhesive composition comprising: a) 10-70 wt.-% of a hydraulic binder, b) 20-90 wt.-% of aggregates, c) 0.01-5 wt.-% cellulose ether, and water; wherein a weight ratio of the water to the hydraulic binder in the range of from 0.3-0.8, and the processable composition has an air content of 0-5 Vol-%; and subsequently applying the produced processable composition on a support element and/or on a cover element with a pumping system.

2. The method of claim 1, wherein the cementitious adhesive composition further comprises 0.1-10 wt.-%, of a polymer.

3. The method of claim 1, wherein the cementitious adhesive composition further comprises 0.001-10 wt.-% of a plasticizer.

4. The method of claim 1, wherein the cementitious adhesive composition further comprises 0.05-2.0 wt.-% of a defoamer.

5. The method of claim 1, wherein the cellulose ether is selected from hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methylcellulose, hydroxylethyl methylcellulose and/or carboxymethyl cellulose.

6. The method of claim 1, wherein the cementitious adhesive composition comprises: a) 20-50 wt.-%, of cement, b) 25-60 wt.-%, of silica sand, c) 0.2-0.6 wt.-%, of cellulose ether selected from hydroxypropyl methylcellulose and/or hydroxylethyl methylcellulose, d) optionally 1-6 wt.-%, of a redispersable polymer, selected from polyacrylate, poly(vinyl acetate), poly(vinyl alcohol), vinyl ester-vinyl acetate copolymer, ethylene-vinyl acetate copolymer and ethylene-vinyl alcohol copolymer or mixtures thereof, e) optionally 0.1-1 wt.-%, of a plasticizer, f) optionally 0.1-0.8 wt.-% of a defoamer.

7. The method of claim 1, wherein the cementitious adhesive composition comprises: a) 30-50 wt.-%, of cement, b) 50-60 wt.-%, of silica sand, c) 0.2-0.6 wt.-%, of cellulose ether selected from hydroxypropyl methylcellulose and/or hydroxylethyl methylcellulose, d) 1-6 wt.-%, of a redispersable polymer, selected from polyacrylate, poly(vinyl acetate), poly(vinyl alcohol), vinyl ester-vinyl acetate copolymer, ethylene-vinyl acetate copolymer and ethylene-vinyl alcohol copolymer or mixtures thereof, e) 0.1-0.5 wt.-%, of a plasticizer, f) 0.1-0.5 wt.-% of a defoamer.

8. The method of claim 1, wherein the air content of the processable composition is 0.1-3 Vol-%.

9. The method according to claim 1, wherein at least during intermixing of the components of the processable composition during the production of the processable composition, air is actively removed.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) In the figures used for explaining the embodiments:

(2) FIG. 1 shows a photograph of a cementitious adhesive layer which has been produced by application of a conventional tile adhesive with a high pressure pump system and an application head with a profiled slot nozzle; and

(3) FIG. 2 shows a photograph of a cementitious adhesive layer which has been produced in a similar manner by application of a tile adhesive according to the invention.

EXEMPLARY EMBODIMENTS

(4) 1. Cementitious Adhesive Compositions

(5) Table 1 shows four inventive adhesive compositions A1-A4. The compositions have been prepared by intermixing all of the commercially available components in dry state. The adhesive composition A1-A4 are present as dry powders and can preferably be used as tile adhesives.

(6) TABLE-US-00001 TABLE 1 Component A1 A2 A3 A4 Hydraulic binder [wt-%] 21.0 45.0 42.0 40.0 Portland cement Aggregate [wt-%] 45.0 51.1 29.33 56.0 Sand (0-1 mm) Cellulose ether [wt.-%] 0.1 0.4 0.30 0.40 hydroxylethyl ethylcellulose Limestone filler [wt-%] 33.9 26.75 Polymer [wt-%] 3.5 1.60 3.0 Ethylene-vinyl acetate copolymer Plasticizer [wt.-%] 0.3 Polycarboxylate ether Defoamer [wt.-%] 0.3 Mixture of alkoxylated fatty alcool and a polyetherol fatty acid on an inert carrier material (Lumiten) Retarder [wt.-%] 0.03 Sodium gluconate
2. Preparation of Processable Compositions

(7) Processable compositions C1-C4 have been obtained by intermixing the dry adhesive compositions A1-A4 with water (weight ratio of water to total weight of dry adhesive composition=0.25-0.26.

(8) For comparison, a reference composition R has been produced with a commercially available adhesive composition for manual application in a similar manner.

(9) Subsequently, the air content has been determined according to DIN EN 1015-7.

(10) All of the so processable compositions C1-C4 had an air content of about 1-2%. In contrast, the reference composition had an air content of about 20%.

(11) 3. Application

(12) The processable compositions C1-C4 as well as the reference composition R have been applied with a pump system and an application head with a profiled slot nozzle (comparable to the one described in DE 198 21 612 A1) with a thickness of 3-6 mm on a cleaned flat plate under identical conditions.

(13) FIG. 1 shows a photograph of the so applied reference composition R with large air voids which are caused by inhomogeneous flow behavior of the adhesive composition during application. In contrast, with inventive composition C1 (FIG. 2), a very homogeneous adhesive layer without any voids is produced.

(14) Thus, adhesive compositions according to the present invention are highly beneficial for use as adhesive in automatic tiling systems.

(15) It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted.