EP-4741432-A1 - TWO-COMPONENT FILLING COMPOSITION FOR DRYWALL APPLICATIONS

EP4741432A1EP 4741432 A1EP4741432 A1EP 4741432A1EP-4741432-A1

Abstract

Inventors

ALTENWEGNER, Florian
LABOUREIX, Gabriel
CHOFFAT, FABIEN
HAEGLER, Matthias
LANGENEGGER, Marcel

Assignees

Sika Technology AG

Dates

Publication Date: 20260513
Application Date: 20241111

Claims (15)

Use of a two-component polymer based putty composition for the covering/filling of joints between plasterboards in dry walls, wherein the composition comprises a polyol component A and a polyisocyanate component B, wherein the two-component polymer based putty composition is preferably free of plasticizers.
Use according to claim 1, wherein the component A and B of the two-component polymer based putty composition are provided in an A/B ratio in the range of from about 1:1 to 10:1, preferably in the range of about 1:1 to 4:1 and more preferably in the range of 1.5:1 to 2.5:1.
Use according to claim 1 or 2, wherein the component A comprises from 50 to 85 wt.-% of one or more polyols, the component B comprises 50 to 85 wt.-% of a polyisocyanate, and the respective components A and B further comprise 8 to 50 wt.-% of a combination of filler and light weight filler and 0.5 to 5 wt.-% of a colorant.
Use according to any one of claims 1 to 2, wherein the component A of the two-component polymer based putty composition comprises a mixture of polymeric polyol and polyol with a molecular weight of 500 or less, preferably wherein the weight ratio of polymeric polyol to polyol with a molecular weight of 500 or less is in the range form 2:1 to 10:1, more preferably form 3:1 to 8:1 and even more preferably from 4:1 to 6:1.
Use according to claim 4, wherein the polymeric polyol is a polyether glycol, preferably selected from polypropylene glycol, polyethylene glycol, copolymers of propylenoxide and ethylene oxide, and polytetrahydrofurane, more preferably wherein the polyether glycol is a blockcopolymer of the type ABA, where A designates end blocks on the basis of ethylene oxide and B designates a middle block on the basis of propylene oxide.
Use according to any one of claims 1 to 5, wherein the two-component polymer based putty composition in the component B comprises a polyisocyanate selected from isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane 4,4'-diisocyanate, hexane diisocyanate, bis(isocyanatomethyl)cyclohexane, tolylene diisocyanate and/or diphenylmethane diisocyanate, preferably wherein the polyisocyanate comprises diphenylmethane diisocyanate.
Use according to any one of claims 1 to 6, wherein the two-component polymer based putty composition, when cured has a Youngs modulus in the range of 10 to 100 MPa, preferably in the range of 20 to 50 MPa and/or an elongation at break in the range from 50 to 200 %, preferably 80 to 175% and more preferably 90 to 150%.
Use according to any one of claims 1 to 7, wherein the two-component polymer based putty composition has one or more of the following properties: - an open time of about 2 min to 10 and preferably 2.5 min to 5 min; - a time until the two component two-component polymer based putty composition is cured to 80% I the range of 45 Min to 120 Min, and preferably 50 Min to 90 Min. - a viscosity of the components A and/or B in the range of 20 to 120 Pas, in particular 30 to 70 Pas.
A drywall construction comprising a truss and a continuous wall of plasterboards applied thereon, wherein gaps and/or joints between adjacent plasterboards are at least partially filled with a two-component polymer based putty composition as described in any one of claims 1 to 8.
A kit comprising a two-component polymer based putty composition as described in any one of claims 1 to 8, where the components A and B are provided in separate compartments, and an applicator, from which the respective components can be mixed and applied to a substrate, wherein preferably the surface applicator is a manual applicator.
Kit according to claim 10, wherein the applicator is provided with a static mixer to mix the components of the two-component polymer based putty composition.
Process for the production of a drywall construction comprising the steps of - providing a drywall truss; - attaching a plurality of plasterboards to the drywall truss in a manner that the edges of the plasterboards contact each other or a spaced at a distance of at most 2 mm; - applying a two-component polymer based putty composition as defined in any one of claims 1 to 8 over the joints of two adjacent plasterboards; - allowing the two-component polymer based putty composition to cure to thereby produce the drywall, preferably at ambient temperature.
Process according to claim 12, wherein after two-component polymer based putty composition has cured, the joint surface is sanded to provide a smooth surface, preferably with 240 sand paper.
Process according to claim 13, wherein after sanding a cover of paint is applied to the surface of the drywall.
Use of a two-component polymer based putty composition to reduce or prevent surface cracks in joints of a drywall.

Description

The present invention is concerned with the use of a two-component polymer based putty composition for the covering/filling of joints between plasterboards in dry walls, wherein the composition comprises a polyol component A and a polyisocyanate B component and is free of plasticizers. The present invention is also concerned with drywall constructions, wherein gaps between adjacent plasterboards are filled with a respective two-component polymer based putty composition, kits constituted from such compositions and applicators for the same, processes for the production of drywalls, which involve the use of a respective composition and a use of a respective composition to reduce or prevent surface cracks in joints of a drywall. State of the art In drywall construction, different types of panels are used to form interior walls and ceilings. Typically, the panels are used in the form of boards, which are attached against frame members, such as in known in the art as balloon frame assemblies. Examples include plasterboard coated with paper, also known as wallboard or drywall, paperless plasterboard made with fiber mats (e.g. fiberglass), and the like. These and other types of boards are typically cut to suitable dimensions and then attached to frame members, e.g. with screws, nails or the like to form wall sections which are formed from several boards. Two panels lying next to each other, which are arranged in the same plane, form a connection seam or joint on vertical walls and horizontal ceilings. If these joints are just filled with a mineral based conventional filler or putty, there is a risk for the formation of cracks filler in the joints, which may form when the putty is dried or when the boards extend or contract due to variations of the temperature. To avoid such crack formation, in the prior art these joints are usually first filled with a putty and then covered with a joint reinforcement tape. Examples of joint reinforcement tapes that can be used and conventional methods for filling joints with such tapes are described, for example, in US Pat. No. 2,850,404 or US Pat. No. 6,668,897. After the compounds, which are applied to cover the joint, have sufficiently dried, the resulting surfaces can be sanded and painted to achieve the desired uniform and aesthetically pleasing appearance. In gypsum drywall construction, the tape which is commonly used to bridge the seam between adjacent plasterboards is usually based on paper. Alternatively, glass fiber tapes or other flat fiber structures can be used. In the course of the preparation of the covered joint, the tape is usually embedded into the joint compound and then covered by at least one subsequent layer of joint filler to provide a uniform surface. The function of the tape in this construction is to bridge the neighboring panels, to give the connection strength and reinforcement against visible hairline cracks on the surface, which can form as a result of shrinkage and settlement when the construction is dried or as a result of mechanical stresses. The introduction of a paper strip involves several repetitive steps, which makes the process relatively time-consuming. In addition, the subsequent spackling is highly demanding on the skill of the worker, because if the strip is improperly applied bubbles can occur, which often will become visible only after the joint has completely dried. In this case, a worker has to cut the tape from the joint and has to again apply a thin layer of joint filler and adhesive tape before he can continue with the next step. Evidently, thus, this conventional method is comparatively complex and error prone. WO 2017/044329 proposes a flexible adhesive composition for filling joints between plasterboard, which is formed from fibers, a binder of polymer resin, water, and a thickener. Instead of a filler, this adhesive composition is applied to the joint edge area between two panels and dried, so that the application of a joint reinforcement tape is no longer necessary. WO 2017/044329 claims that compared to conventional joint reinforcement tapes even better mechanical properties are achieved. Whereas the solution described in WO 2017/044329 is quite simple and does not involve many steps, the composition described in this document comprise high quantities of water, so that the composition is not suitable to fill joints between plasterboards with curved edges. In addition, since the compositions in this document are water based, some time for drying is necessary before subsequent treatment step such as sanding can be applied to the surface. WO 2023/274487 A1 describes a polymer based sprayable mixture for covering joints between plasterboards, which are formed from 0.01 to 10 wt.-% of a fibrous material, 1 to 20 wt.-% of a binder, 1 to 10 wt.-% of a thickener and 50 to 07.99 wt.-% of a solvent, wherein the fibrous material and binder are present in a ration of from 1:1 to 1:5. This mixture is used similar to an adhesive tape, i.e.