METHOD OF CHECKING AN ADHESIVE

Description

DESCRIPTION Attached to a patent application for an INDUSTRIAL INVENTION having by title “METHOD OF VERIFYING AN ADHESIVE” On behalf of: KERAKOLL SPA VIA DELL'ARTIGIANATO 9 41049 SASSUOLO (MO) ******* The present invention relates to a method of testing an adhesive and in particular a method for testing behavior and resistance of a tile adhesive. Tile adhesives are divided, for example, according to the standard 5 UNI EN 12004, in different categories each characterised by relative properties and / or performance. In general, the requirements for stickers to be able to be placed in one category or another and the testing methods to verify such requirements are defined by the standards themselves. 10 Among the optional requirements that characterize the adhesives there is the deformation transversal which however does not represent a real behavior of the adhesive. Schematically, in fact, the transverse deformation is verified on a tongue of adhesive while the real “glued system” of laying is a layered system made up of various layers that go from the bottom of 15 laying, floor or wall, to tiling. In this scenario, both cladding materials and that the laying funds. For example, in the first market, large-scale slabs are emerging made of ceramic material, stone materials with fibre mesh or mat 20 glass while in the second ones heating bottoms are spreading with prefabricated panels made of insulating material that are not very rigid and not very stable. The main drawback of the known verification methods is that they are always less consistent with the real working conditions of the adhesives and therefore they may provide non-significant parameters of the real performance of the product. For example, in real applications, stresses also arise parallel to the installation plane, for example due to differential movements between the layers in play, caused by shrinkage and / or expansion. 5 There is a need in the sector for a verification or testing method for the adhesives more reliable in evaluating the durability of the “glued system” to all the stresses that act on it. In this context, we want to propose a method for testing an adhesive in capable of overcoming at least some of the drawbacks of the prior art 10 above mentioned and to satisfy the aforementioned need. In particular, it is the purpose of the present invention to make available a method of testing an adhesive in which the adhesive is stressed more similar to actual conditions of use. This aim is achieved by a verification method comprising the 15 technical features set out in one or more of the attached claims. The dependent claims correspond to possible different forms of realization of the invention. In accordance with one aspect, the present invention relates to a method of checking a sticker. 20 The test method is preferably intended for testing adhesives cementitious defined, schematically, as a mixture of hydraulic binders organic aggregates and additives mixed with water or a liquid additive added just before use, for example, stickers class C according to UNI EN 12004 standard. 25 The Applicant observed that since the funds and covering materials they are increasingly flexible and their intended uses are increasingly technical, they can verify stresses on the installed system that act parallel or outside the installation plane and acting eccentrically on the tiling (so not with a centered action) determining, for example 30 example, bending moments (if the stresses act out of the plane of laying) or torsional moments (if the stresses are parallel to the plane of installation, such as, for example, in a driveway) which also act and in especially the sticker. In one aspect, the method replicates the above mentioned stresses for verify the behavior of the adhesive inserted in a layered system 5 composed of base and lining. With regard to the terms and definitions adopted in this description, you can also refer to the glossary of the UNI EN standard 12004. The method of testing an adhesive involves preparing a test piece 10 comprising at least one sub-floor slab defining a laying plane, the adhesive applied to the subfloor, a tile adhered to the underlayment plate using the adhesive so as to present a first part adhered to the subfloor (via adhesive) and a protruding part at least from the sticker. 15 The cantilevered part protrudes from the attached part and has a first and a second lateral edge that extends from it. The verification method involves applying a torque and / or a bending moment to the adhesive, preferably via the cantilever part of the tile. 20 The verification method includes increasing the torque and / or the bending moment applied until the glued system breaks. Preferably, the torque and / or bending moment are continuously increased during a sticker check. Alternatively, the torque and / or bending moment can 25 to be increased discretely, in steps, during a test of the sticker. Advantageously, the applied torque and / or bending moment to the adhesive preferably via the overhanging part of the tile they can stress the adhesive itself both parallel to the installation surface 30 both outside the installation plane reproducing stresses comparable with those to which the adhesive is actually subject in modern applications construction. Advantageously, the indicated stress combinations provide for the bending moment stress, twisting moment, bending moment 5 and twist combined. Preferably, when the twisting moment and the bending moment are applied in combination, the specimen is stressed to a value preset torque, for example 1 KN, and the bending moment until the specimen breaks. 10 Preferably, applying a torque includes applying to the a force parallel to the bearing plane starts cantilevering. Preferably, the parallel force is applied to the first or second edge edge. Preferably, applying a bending moment includes applying to the 15 a force orthogonal to the laying plane is applied as a cantilever. Advantageously, the cantilevered part defines an arm through which the force is transmitted to the adhesive causing a moment on the same. Moment means a force or a sum of forces applied with an arm, that is, a distance between the application point and 20 stress point. To apply torque to the adhesive the force can also be applied to the first part adhered and the arm is shorter than the arm that occurs when force is applied to the cantilevered part. Preferably, the method comprises gluing to the cantilevered part of the 25 tile, on the opposite side to the subfloor slab, a plate metal to which at least the bending moment and / or at least the force must be applied orthogonal to the installation plane. The force orthogonal to the laying plane can be applied with direction incoming or outgoing from the installation plane. Advantageously, the metal plate can make it more practical the application of moment to the adhesive or a force to the cantilevered part of the tile Preferably, preparing the specimen includes preparing the plate 5 underlayment, apply the adhesive on the underlayment slab, preferably using a notched trowel, apply the tile to the adhesive, apply a force to the tile, at least in correspondence with the adhesive orthogonal to the installation plane. Preferably, the testing method includes curing the specimen. 10 In one aspect, the present invention relates to a test specimen preferably intended for a method of testing an adhesive in accordance with with the previous appearance. The test piece comprises at least one subfloor slab defining a plane of installation, an adhesive applied on the subfloor slab, a tile 15 attached to the subfloor plate using the adhesive so as to present a first part adhered to the substrate plate using the adhesive and a protruding part at least from the adhesive and, preferably, from the plate background. The overhanging part of the tile protrudes from the adhered part and presents 20 a first and a second lateral edge extending from said adhered part beyond the same. Preferably the subfloor is cementitious. Preferably the adhesive is cementitious. Preferably, the cantilevered part and the bonded part have the same 25 surface. Further features and benefits of this solution will appear made clearer by the indicative, and therefore non-limiting, description, of at least one preferred but not exclusive embodiment of a method of testing an adhesive and a test specimen for a testing method 30 of a sticker. This description will be presented below with reference to the united drawings, provided for indicative purposes only and therefore not limiting, in which: - Figure 1 illustrates a test specimen for a method of testing an adhesive in accordance with the description in a schematic perspective view; 5 - Figure 2 illustrates a test specimen for a method of testing an adhesive in accordance with the description in a schematic perspective view; - figure 3 shows the specimen of figure 2 in a lateral view schematic in one phase of the verification method in accordance with the description; 10 - Figure 4 illustrates a test specimen for a method of testing an adhesive in a top plan view in one phase of the verification method in accordance with the description; - Figure 5 illustrates a test specimen for a method of testing an adhesive in a schematic perspective view in one phase of the verification method in 15 agree with the description. With particular reference to figure 1, the number 1 indicates a test piece according to the present invention. Test specimen 1 comprises a sub-plate 2 which defines a plane of pose P. 20 For example, the subfloor slab 1 is of a cementitious nature, preferably of the type described in the UNI EN12004 standard. Test piece 1 comprises an adhesive 3 applied to the substrate slab 2. Adhesive 3 is for example a cementitious adhesive or a cementitious adhesive. class C according to UNI EN 12004 standard. 25 Advantageously, the verification method according to the present description can be used to check any 3 sticker that needs to be used in test 1 as will be better explained below. Please note that in the attached schematic figures the dimensions of the specimen 1 are not necessarily to scale but functional to the present 30 description. Test specimen 1 comprises a tile 4 attached to the subfloor slab 2 via sticker 3. Tile 4 has a first part 4a adhered to the base slab 2 through the adhesive 3 and a second part 4b cantilevered part at least 5 from the adhesive and, preferably, from the underlayment plate 2, as illustrated in the figures. The second cantilevered part 4b extends or extends from the first part 4a adhered beyond the subfloor slab 2. Preferably, the first part 4a and the second part 4b have the same 10 area. For example, tile 4 can be a ceramic tile obtained for pressing according to the UNI EN 14411 standard of type Bia, completely vitrified and with water absorption less than or equal to 0.5%, unglazed (UGL), with one adhesive contact surface 15 planar and with dimensions 50 + / 1 mm x 100 + / -1 mm (width per length). The second embossed part 4b has a first and a second edge 5, 6 lateral extending from the first 4th part attached. References 5 and 6 practically indicate the portions of the edges of tile 4 20 corresponding to the second cantilevered part 4b of the same. With reference to figures 2 and 3, specimen 1 comprises a plate 7, metal example, glued to the second part 2a of the tile 2 from opposite side of the subfloor slab 2 to the tile 2 itself. A method of testing the adhesive 3 comprises preparing a test specimen 1 25 previously described. Preferably, preparing specimen 1 includes preparing the plate underlay 2 and apply adhesive 3 on underlay slab 2. Preferably, apply the adhesive on the subfloor 2 includes apply the adhesive 3 with a notched trowel not illustrated so that 30 the adhesive 3 presents a succession of crests 3a and grooves 3b. For example, you can use a notched trowel with 6x6 mm teeth. Adhesive 3 can be mixed according to UNI EN12004 point 6. Preparing test 1 includes applying tile 4 to adhesive 3. Preferably, preparing test 1 includes applying the tile 5 4 on the sticker 3 after a time t3, for example 5 minutes, from application of the adhesive 3 on the underlayment plate 2. Tile 4 is placed on adhesive 3 so that the adhesive wets the first part 4a of tile 4 while the second part 4b remains at overhang. 10 In a favorite example, the first part 4a is equal to the second part 4b of tile 4. The first part 4a and the second part 4b can be for example two squares with sides 5, i.e. the first and second edges 5 and 6 measure 5 cm. To properly apply the tile 4 on the adhesive 3 it can be 15 used a jig not illustrated. Prepare test 1 preferably includes applying on the tile 4, at least at the adhesive 3, a force F8, preferably orthogonal to the installation plane P, for a time t8 so as to ensure adequate pressure on the tile 4 and a suitable 20 sticker transfer 3. In the example shown in figure 5, apply a force F8 to tile 4 involves placing a weight 8 on the first part 4a of tile 4. For example, weight 8 is a 20 + / - 2 N weight, t8 is 30 s and the surface contact area of ​​weight 8 with tile 4 is 50x50 mm. 25 Preferably, preparing specimen 1 includes curing specimen 1 same or to store the specimen under certain environmental conditions for a certain period of maturation time ts in order to purchase optimal characteristics for its use. For example, specimen 1 can be cured for 28 days in a 30 environment in which the following conditions exist: Temperature: 23 + / - 2 °C Relative humidity: 50 + / - 2% Air speed: < 0.2 m / s The verification method according to the description includes applying a torque Mt at adhesive 3, illustrated counterclockwise in the figure 5 4. The torque Mt can be applied indifferently in the direction clockwise or counterclockwise. The torque is preferably applied to the adhesive 3 via the second part 4b embossed tile 4. 10 Preferably, apply the torque Mt includes applying to tile 4 a force Ft parallel to the laying plane. Preferably, the force Ft is applied to the second part 4b of the tile, for example at the first or second edge 5, 6 of the same. Preferably, the force Ft is orthogonal to the first and second edges 5, 6. 15 The torque Mt applied to the adhesive 3 depends on the arm of the force Ft relative to the adhesive 3 itself. The verification method according to the description includes applying a bending moment Mf at adhesive 3, illustrated with counterclockwise direction in figure 3. 20 The bending moment Mf can be applied indifferently in the direction clockwise or counterclockwise. The bending moment is applied to the adhesive 3 via the second part 4b a tile overhang 4. Preferably, applying the bending moment Mf includes applying 25 to the second part 4b of tile 4 a force Ff orthogonal to the plane of pose P. Preferably, the force Ff is orthogonal to the bearing plane P. The bending moment Mf applied to the adhesive 3 depends on the arm of the force Ff with respect to the adhesive 3 itself. 30 Preferably, the force Ff is applied to the tile 4 via the plate metallic 7. For example, you can use a dynamometer configured to perform a pull-out test that acts with a tensile force on the plate 7 previously glued on the surface of tile 4 from rip. 5 In this case, preparing test piece 1 includes gluing, for example with two-component adhesive, on the second part 4b the metal plate is embossed 7. The torsional moment Mt and the bending moment Mf can be applied simultaneously or separately, called bending moment 10 being applied via said metal plate. The force Ft and / or the force Ff can also be the resultant of more forces applied to test 1. The verification method includes increasing the torque Mt and / or the bending moment Mf applied until specimen 1 fails. 15 The twisting moment Mt and / or the bending moment Mf can be increased continuously until failure or discreetly. In one embodiment, the verification method may comprise apply the torque Mt without breaking specimen 1 for pre-tension it and then apply the bending moment Mf. 20 Preferably, the method comprises applying a stress parallel to the laying plane P on the first or second edge 5, 6 of the tile 4 in order to generate the torque Mt (given by the eccentric cut, compared to the adhesive 3, applied) without causing the specimen 1 to break pre-tensioning it up to a preset value of the applied force Ft, to 25 example 1 KN. The method then includes applying a stress orthogonal to the installation plane P, i.e. the force Ff at the second part 4b embossed tile with special tool to generate the bending moment Mf. The test conditions are preferably consistent and defined. For example, the environmental conditions in which the checks are carried out can be: temperature: 23 + / - 2 °C, relative humidity: 50 + / - 2 %, speed of air: < 0.2 m / s. Preferably, the materials used should be brought to the conditions of 5 tests at least 24 hours before the test. Preferably, the tests are carried out at the end of the seasoning process. The verification method includes recording the torque Mt and / or the bending moment Mf which determined the breakage of specimen 1. Record the torque Mt and / or bending moment Mf that have 10 determined the failure of specimen 1 may include recording the force Ff and / or the force Ft required for the failure of specimen 1. Preferably the forces are measured in N. the value of the forces Ft and Ff for the respective arm due to the second cantilevered part 4b of tile 4 provide the torque Mt and / or bending moment Mf to which it has been 15 specimen 1 was subjected to the test; the bending moments Mf and torsional moments Mt are expressible in Nmm and therefore in Kgm. Preferably, an adhesive resistance 3 to torque and / or bending moment is determined by an average value calculated on a plurality of test specimens 1, for example 10, subjected to verification. THE AGENCY Eng. Tommaso Puggioli

Claims

1. Method of testing an adhesive (3), said method comprising prepare a test piece (1) including a base plate (2) defining a laying plane (P), the adhesive (3) applied on the slab of 5 underlay (2), a tile (4, 4a, 4b) featuring a first part (4a) adhered to the base plate (2) using the adhesive (3) and a second part (4b) protruding at least from the adhesive (3) and preferably from the plate background (2), said second part (4b) cantilevered presenting a first and a second lateral edge (5, 6) extending from said first part (4a), 10 said verification method comprising applying a torque (Mt) and / or a bending moment (Mf) to the adhesive preferably via said second part (4b) overhanging the tile (4), increase the moment torque (Mt) and / or bending moment (Mf) applied until the failure of the audition (1); 15 record the torque (Mt) and / or bending moment (Mf) that have determined the breakage of the specimen (1).

2. Verification method according to claim 1 wherein applying a torque (Mt) comprises applying to said first edge (5) or to 20 said second edge (6) of the second portion (4b) cantilevered a force (Ft) parallel to the laying plane (P) 3. Verification method according to claim 1 or 2 wherein applying a bending moment (Mf) includes applying to said second part (4b) a 25 I exert a force (Ff) orthogonal to the bearing plane (P).

4. Verification method according to any of the preceding claims comprising gluing to said second part (4b) in cantilever, on the part opposite to the said base plate (2), a plate (7) 30 preferably metallic, said bending moment (Mf) being applied via said plate (7).

5. Verification method according to claims 3 and 4 wherein said force (Ff) orthogonal is applied via said plate (7). 5 6. Verification method according to any of the preceding claims in which preparing the test piece (1) includes preparing the plate of underlay (2), apply the adhesive (3) on the underlay plate (2), apply the tile (4) embossed on the adhesive (3), apply on the tile (4), at least at the adhesive (3), an orthogonal force (F8) 10 on the laying floor (P).

7. Verification method according to any of the preceding claims including curing the specimen (1). 15 8. Verification method according to any of the preceding claims where to apply the adhesive (3) on the underlayment plate (2) includes apply the adhesive with a notched trowel.

9. Verification method according to any of the preceding claims 20 including applying the torque (Mt) without breaking the specimen (1) to preload the specimen (1) and apply the bending moment (Mf) until break the test piece (1).

10. Test piece for a method of testing an adhesive (3), called test piece 25 including: a subfloor slab (2) defining a laying plane (P); the adhesive (3) applied on the underlayment plate (2); a tile (4) attached to the subfloor slab (2) using adhesive (3) so as to present a first part (4a) adhered, via the adhesive (3), 30 to the subfloor slab (2) and a second part (4b) at least overhanging from the adhesive (3) and preferably from the underlayment plate (2), called second part (4b) cantilevered protruding from said first part (4a) adhering and presenting a first and a second lateral edge (5, 6) extending from said first (4th) attached part. 5 11. Verification method according to any of claims 1 to 9 and test piece according to claim 10 wherein the subfloor plate (2) is cementitious.

12. Verification method according to any of claims 1 to 9 10 and test piece according to claim 10 or 11 wherein the adhesive (3) is cementitious.

13. Verification method according to any of claims 1 to 9 and test piece according to any of claims 10 to 12 wherein the 15 second part (4b) cantilevered and the first part (4a) attached have the same surface.

14. Test piece according to any of claims 10 to 13 for a method of testing an adhesive according to any of the claims 20 from 1 to 9. Bologna, September 5, 2024 THE AGENCY Eng. Tommaso Puggioli

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