U.S. patent application number 16/922344 was filed with the patent office on 2020-10-22 for peelable adhesive composition.
This patent application is currently assigned to BOSTIK SA. The applicant listed for this patent is BOSTIK SA. Invention is credited to Jessie CASIMIRO, Eric VERSCHEURE.
Application Number | 20200332158 16/922344 |
Document ID | / |
Family ID | 1000004939846 |
Filed Date | 2020-10-22 |
United States Patent
Application |
20200332158 |
Kind Code |
A1 |
CASIMIRO; Jessie ; et
al. |
October 22, 2020 |
PEELABLE ADHESIVE COMPOSITION
Abstract
The invention relates to an adhesive composition comprising at
least one latex and at least one polymer composition having a glass
transition temperature ranging from -50.degree. C. to 0.degree. C.,
said adhesive composition being particularly suitable for bonding
flexible surface coverings having a high dimensional variability.
The invention also relates to a membrane obtained after drying of
the adhesive composition according to the invention, a combination
of a flexible surface covering with an adhesive composition
according to the invention, a method of application of a flexible
surface covering onto a substrate as well as a substrate covered
with a peelable adhesive membrane according to the invention.
Inventors: |
CASIMIRO; Jessie; (Brie
Comte Robert, FR) ; VERSCHEURE; Eric; (Vernou La
Celle Sur Seine, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BOSTIK SA |
Colombes |
|
FR |
|
|
Assignee: |
BOSTIK SA
Colombes
FR
|
Family ID: |
1000004939846 |
Appl. No.: |
16/922344 |
Filed: |
July 7, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14731693 |
Jun 5, 2015 |
10745594 |
|
|
16922344 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08G 2170/80 20130101;
B32B 2309/08 20130101; B32B 38/10 20130101; B32B 37/12 20130101;
C09D 123/08 20130101; C09J 133/10 20130101; C08K 2003/265 20130101;
C09J 107/02 20130101; C09D 5/20 20130101; C09D 133/04 20130101;
C09J 107/00 20130101; C09J 133/02 20130101; C09D 175/04 20130101;
C09J 123/08 20130101; C09J 175/04 20130101; C08K 3/26 20130101;
C09J 133/08 20130101 |
International
Class: |
C09J 107/02 20060101
C09J107/02; C08K 3/26 20060101 C08K003/26; B32B 37/12 20060101
B32B037/12; B32B 38/10 20060101 B32B038/10; C09D 5/20 20060101
C09D005/20; C09D 133/04 20060101 C09D133/04; C09J 123/08 20060101
C09J123/08; C09J 133/02 20060101 C09J133/02; C09D 123/08 20060101
C09D123/08; C09J 107/00 20060101 C09J107/00; C09D 175/04 20060101
C09D175/04; C09J 133/08 20060101 C09J133/08; C09J 133/10 20060101
C09J133/10; C09J 175/04 20060101 C09J175/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 5, 2014 |
FR |
14/55.130 |
Claims
1-15. (canceled)
16. A method of application of a flexible surface covering onto a
substrate, comprising: a) applying a layer of an adhesive
composition onto the substrate, b) adhering the flexible covering
onto the substrate, said adhesive composition comprising: (a) 30%
to 45% by weight of dry matter with respect to the total weight of
the adhesive composition, of at least one natural latex, (b) 5% to
40% by weight of dry matter with respect to the total weight of the
adhesive composition of at least one polymer composition having a
glass transition temperature of -50.degree. C. to 0.degree. C.,
said polymer composition comprising: i) at least one copolymer or a
mixture of at least two polymers comprising at least one
(meth)acrylate or (meth)acrylic monomer, and/or ii) at least one
mixture of at least two polymers comprising at least one polyester
and at least one polyurethane, and/or iii) at least one vinyl
acetate and ethylene copolymer, (c) 5% to 40% by weight with
respect to the total weight of the adhesive composition of at least
one filler.
17. The method of application according to claim 16, wherein a) the
latex represents from 30% to 40% by weight of dry matter with
respect to the total weight of the adhesive composition, and/or b)
the polymer composition represents from 6% to 25% by weight of dry
matter with respect to the total weight of the adhesive
composition, and/or c) the filler(s) represent(s) from 15% to 35%
by weight of the total weight of the composition.
18. The method of application according to claim 16, wherein the
filler and/or the mixture of fillers has an apparent density
ranging from 0.60 to 1.80.
19. The method of application according to claim 16, wherein the
filler and/or the mixture of filler has an apparent density ranging
from 1.30 to 1.70.
20. The method of application according to claim 16, wherein the
filler is a mineral filler.
21. The method of application according to claim 16, wherein the
polymer composition has a glass transition temperature of
-40.degree. C. to -10.degree. C.
22. The method of application according to claim 16, wherein the
polymer composition is a vinyl acetate, ethylene and acrylate
terpolymer.
23. The method of application according to claim 16, wherein the
polymer composition comprises a vinyl acetate, ethylene and
acrylate terpolymer and a mixture of polyester and of
polyurethane.
24. The method of application according to claim 16, wherein the
polymer composition further comprises fibers.
25. The method of application according to claim 16, wherein the
flexible covering is a covering having a maximum dimensional
variability measured according to the Freudenberg test greater than
or equal to 0.2%.
26. The method of application according to claim 16, wherein the
quantity of adhesive composition applied is greater than or equal
to 200 g/m.sup.2.
27. The method of application according to claim 16, comprising
before a), applying a weft or a woven or non-woven reinforcing tape
onto the substrate.
28. The method of application according to claim 25, comprising
holding the flexible surface covering having a maximum dimensional
variability measured according to the Freudenberg test greater than
or equal to 0.2%.
29. A method for renovating a substrate coated with a peelable
adhesive film, obtained after drying of the adhesive composition
according to claim 16, and with a flexible surface covering, said
method comprising lifting the flexible surface covering.
Description
TECHNICAL FIELD
[0001] The present invention relates to a peelable adhesive
composition. The invention also relates to a peelable membrane
obtained by drying the adhesive composition according to the
invention. A subject of the invention is also the combination of a
surface covering with the peelable adhesive composition, and a
method for applying a surface covering. The invention also relates
to a method for renovating a surface covering. The invention also
relates to the use of the peelable adhesive composition for holding
a flexible surface covering having a maximum dimensional
variability measured according to the Freudenberg test greater than
or equal to 0.2%.
STATE OF THE ART
[0002] The replacement of a flexible floor covering is an operation
which has for a long time posed numerous problems to professionals
and individuals.
[0003] Solutions for the non-permanent fixing of the covering
exist, either by the use of double-sided adhesive tapes or by the
use of a fixing agent constituted by a pressure-sensitive adhesive.
These solutions allow a rapid renovation of premises but they are
to be reserved for living areas with low traffic. In fact the
strength of the fixing and the durability of the bonding are low.
Moreover, the use of double-sided adhesive tapes causes excessive
thicknesses which can lead to blisters when furniture is moved, or
give rise to marks on the PVC (known as "ghosting").
[0004] In the case of a fixing using standard adhesives which is
the common solution at present, replacement for renovation of a
previously-bonded flexible floor covering (for example a carpet),
involves a succession of time-consuming and tedious steps before it
is possible to bond a new covering. Firstly the old coverings have
to be taken up by force, then the adhesive residues have to be
removed. So this must be carried out either using manual tools
(scrapers) or with the assistance of a stripper or solvent-based
remover.
[0005] In case of unevenness it is also necessary to sand and level
the floor using a levelling compound before it is possible to apply
a new layer of adhesive in order to fix the new covering.
[0006] Moreover, adhesive and potentially residues of inorganic
binder such as levelling agent remain stuck to the old covering,
which constitutes an obstacle to its recycling.
[0007] In the case of large surface areas such as commercial
premises, the replacement of the covering will require closure of
the premises for a relatively long time which is necessary for all
of the renovation steps.
[0008] Flexible floor coverings made of rubber are used in numerous
types of high-traffic premises such as airports or hospitals. Due
to their rigidity, this type of coverings deteriorates less rapidly
than PVC-type flexible flooring. However, coverings made of rubber
are more difficult to bond as they are sensitive to temperature
variations and are therefore more deformable. In fact, when the
flexible rubber covering is bonded with an adhesive that is too
soft or unsuitable, the adhesive follows the variations in the
covering and does not hold it. Blistering and bulging phenomena at
the joints are then observed right from the first few hours
following the adhering of the covering.
[0009] Most standard acrylic adhesives do not allow coverings made
of rubber to be bonded, as they are too soft and do not have
sufficient affinity with rubber. Furthermore, these adhesives do
not allow subsequent removal of the covering without leaving
residues either on the floor or on the covering.
[0010] The application EP 2610317 describes a peelable adhesive
composition comprising from 6 to 28% by weight of dry matter of
natural latex and from 10 to 40% by weight of dry matter of a
polymer composition having a glass transition temperature ranging
from -50.degree. C. to 0.degree. C. This application states that
for coverings having significant dimensional variability, (e.g.
coverings made of rubber), it is preferable to apply a standard
adhesive in addition to the peelable adhesive composition in order
to ensure satisfactory bonding.
[0011] At present there is thus no simple, strong solution for
bonding and holding all types of flexible floor coverings, in
particular floor coverings having a significant dimensional
variability, which can be easily and quickly removed subsequently,
in order to retrieve on the one hand the original substrate for
renovation, and on the other hand the original flexible covering
for recycling.
SUMMARY OF THE INVENTION
[0012] The purpose of the present invention is to provide an
adhesive composition at least partially overcoming the
abovementioned drawbacks.
[0013] To this end, the present invention proposes an adhesive
composition comprising: [0014] a) from 30% to 45% by weight of dry
matter with respect to the total weight of the adhesive
composition, of at least one natural or synthetic latex, [0015] b)
from 5% to 40% by weight of dry matter with respect to the total
weight of the adhesive composition, of at least one polymer
composition having a glass transition temperature ranging from
-50.degree. C. to 0.degree. C., said polymer composition
comprising: [0016] i) at least one copolymer or a mixture of at
least two polymers comprising at least one (meth)acrylate or
(meth)acrylic monomer, and/or [0017] ii) at least one mixture of at
least two polymers comprising at least one polyester and at least
one polyurethane, and/or [0018] iii) at least one vinyl acetate and
ethylene copolymer. [0019] c) from 5% to 40% by weight with respect
to the total weight of the adhesive composition of at least one
filler.
[0020] According to an embodiment of the invention, the latex
represents from 30% to 40%, preferably from 31% to 38% by weight of
dry matter with respect to the total weight of the adhesive
composition.
[0021] According to an embodiment of the invention, the polymer
composition represents from 6% to 25%, preferably from 10% to 20%
by weight of dry matter with respect to the total weight of the
adhesive composition.
[0022] According to an embodiment of the invention, the filler has
an apparent density ranging from 0.60 to 1.80, preferably from 1.30
to 1.70.
[0023] According to an embodiment of the invention, the mixture of
fillers has an apparent density ranging from 0.60 to 1.80,
preferably from 1.30 to 1.70.
[0024] According to an embodiment of the invention, the filler(s)
represent(s) from 15% to 35%, preferably from 20% to 30% by weight
of the total weight of the composition.
[0025] According to an embodiment of the invention, the filler is a
mineral filler, preferably selected from calcium carbonate,
magnesium carbonate, sand, alumina, hydrated alumina, magnesium
silicate, aluminium silicate, sodium silicate, potassium silicate,
mica and silica.
[0026] According to an embodiment of the invention, the polymer
composition has a glass transition temperature ranging from
-40.degree. C. to -10.degree. C., preferably ranging from
-37.degree. C. to -15.degree. C.
[0027] According to an embodiment of the invention, the polymer
composition is a vinyl acetate, ethylene and acrylate
terpolymer.
[0028] According to an embodiment of the invention, the polymer
composition comprises a vinyl acetate, ethylene and acrylate
terpolymer and a mixture of polyester and polyurethane.
[0029] According to an embodiment of the invention, the adhesive
composition also comprises fibres, preferably cellulose fibres,
glass fibres, rubber fibres, natural fibres, such as cotton,
viscose, jute, sisal, or synthetic fibres, such as polyamide,
polyester, polyacrylonitrile, polypropylene, polyethylene.
[0030] The present invention also proposes a membrane obtained by
drying the adhesive composition according to the invention.
[0031] The present invention also relates to the combination of a
flexible surface covering with an adhesive composition according to
the invention.
[0032] The present invention also proposes a method of application
of a flexible surface covering onto a substrate comprising the
following steps: [0033] a) applying a layer of adhesive composition
according to the invention onto the substrate, [0034] b) adhering
the flexible covering onto the substrate.
[0035] According to an embodiment of the invention, the flexible
covering is a covering having a maximum dimensional variability
measured according to the Freudenberg test greater than or equal to
0.2%.
[0036] According to an embodiment of the invention, the quantity of
adhesive composition applied is greater than or equal to 200
g/m.sup.2, preferably greater than or equal to 250 g/m.sup.2, yet
more preferably greater than or equal to 300 g/m.sup.2, more
particularly greater than or equal to 350 g/m.sup.2.
[0037] According to an embodiment of the invention, the application
method comprises before step a), a step of applying a weft or a
woven or non-woven reinforcing tape onto the substrate.
[0038] The invention also proposes a substrate covered with a
peelable adhesive membrane according to the invention and a
flexible surface covering.
[0039] According to an embodiment of the invention, the flexible
surface covering is a flexible surface covering having a maximum
dimensional variability measured according to the Freudenberg test
greater than or equal to 0.2%.
[0040] The invention also proposes a method for renovating a
substrate according to the invention, comprising a step of lifting
the flexible surface covering.
[0041] The invention also proposes the use of the adhesive
composition according to the invention, for holding a flexible
surface covering having a maximum dimensional variability measured
according to the Freudenberg test greater than or equal to
0.2%.
[0042] The advantages of the present invention are the following:
[0043] the adhesive composition of the invention makes it possible
to bond and hold all types of coverings, in particular coverings
having a high dimensional variability, without having to use an
additional strong adhesive, [0044] the composition of the invention
makes it possible, after drying, to easily separate the flexible
covering from the substrate, while leaving the support and the
covering intact with practically no adhesive residue, [0045] the
composition of the invention is an adhesive composition which,
after drying, forms a peelable film, also called a membrane. A
single composition therefore makes it possible to ensure the
bonding and the subsequent unsticking of the covering, [0046] the
adhesive composition of the invention offers long-lasting bonding
suited to high-traffic premises, [0047] the adhesive composition of
the invention is equally suitable for application onto floors and
walls, [0048] the method of application of the surface covering of
the invention is simple to implement since it requires the
application of a single layer of adhesive only, [0049] the method
for bonding the surface covering of the invention does not require
the use of several coverings one of which would remain durably
fixed to the floor, [0050] the covering and the peelable adhesive
of the invention can be removed manually, without requiring the use
of scraper-type tools. The film originating from the drying of the
adhesive composition can be removed from the substrate or from the
covering without use of chemicals and without using particular
mechanical equipment, [0051] the invention allows recycling of the
covering, after unsticking and removing (or lifting) the peelable
film, the latter being free from adhesive residue.
[0052] Other characteristics and advantages of the invention will
become apparent on reading the following description of a preferred
embodiment of the invention, given by way of example, and with
reference to the attached drawing.
BRIEF DESCRIPTION OF THE FIGURES
[0053] FIG. 1 is a diagram representing an embodiment of the
invention after application of the peelable adhesive (1) and of the
flexible covering (2) onto a substrate (3).
[0054] FIG. 2 is a diagram representing the state of the substrate
(3) and of the flexible covering (2) after renovation.
[0055] FIG. 3 is a diagram illustrating a method for bonding a
flexible covering (2) involving a weft or a woven or non-woven
reinforcing tape (5).
[0056] FIG. 3a shows in perspective the initial substrate 3. FIG.
3b shows in perspective the substrate 3 on which a weft 5 is
placed. FIG. 3c shows in perspective the substrate 3 covered by the
weft 5 to which the adhesive composition 1 is applied using an
applicator 6. FIG. 3d shows in cross-section the substrate 3
covered by the adhesive composition 1. FIG. 3e shows the adhesive
composition 1 comprising the weft 5.
[0057] FIG. 4 is a photo illustrating the blistering and lifting
phenomenon.
[0058] FIG. 5 is a diagram illustrating the Freudenberg test
device.
[0059] FIG. 5a is a diagrammatic representation of the device used
for the Freudenberg test.
[0060] FIG. 5b shows location of reference points A-D on the
covering.
DETAILED DESCRIPTION OF THE INVENTION
[0061] The present invention proposes a peelable adhesive
composition comprising: [0062] from 30 to 45% by weight of dry
matter with respect to the total weight of the adhesive composition
of at least one natural or synthetic latex, [0063] from 5% to 40%
by weight of dry matter with respect to the total weight of the
adhesive composition, of at least one polymer composition having a
glass transition temperature ranging from -50.degree. C. to
0.degree. C., said polymer composition comprising: [0064] at least
one copolymer or mixture of at least two polymers comprising at
least one (meth)acrylate or (meth)acrylic monomer, and/or [0065] at
least one mixture of at least two polymers comprising at least one
polyester and at least one polyurethane, and/or [0066] at least one
vinyl acetate and ethylene copolymer, [0067] from 5% to 40% by
weight of at least one filler.
[0068] By peelable adhesive composition is meant an adhesive
composition which, after application onto a substrate and drying,
forms a film or membrane which can be easily removed without
leaving residues.
[0069] According to the present invention, the latex can be a
natural latex for example obtained from the rubber tree or a
synthetic latex which can be obtained by polymerization of
isoprene. Among the latexes which can be used in the adhesive
compositions according to the invention, the emulsions of
polyisoprenoid-type polymers may be mentioned.
[0070] Preferably, the latex is a natural latex. In particular, the
natural latex can be a natural latex of standard grade, a natural
latex having a low ammonia content, a natural latex having a high
ammonia content. Generally, water represents from 30% to 45% of the
weight of the natural latex, typically 38.5% of the weight of the
natural latex.
[0071] Preferably, the natural latex is a natural latex having an
ammonia content ranging from 0.05 to 1% by weight with respect to
the weight of natural latex. It is possible to choose a natural
latex having a low ammonia content, i.e. generally ranging from
0.05% to 0.4%, preferably less than 0.1% by weight with respect to
the weight of natural latex, or a natural latex having a high
ammonia content, i.e. generally ranging from 0.5 to 1% by weight
with respect to the weight of natural latex. It is well known to a
person skilled in the art that ammonia makes it possible to
stabilize natural latex.
[0072] The copolymers or polymers used in the invention in order to
form the polymer composition, can be in the form of an aqueous
emulsion or in the form of a redispersible powder which, after
addition of water, forms an aqueous solution. The form in which the
copolymer or mixture of polymers is used depends on its solubility
in water.
[0073] According to an embodiment of the invention, the filler(s)
have an apparent density ranging from 0.60 to 1.80, preferably from
1.30 to 1.70.
[0074] In the case where the adhesive composition comprises a
mixture of several different fillers (difference of chemical nature
and/or of properties), each filler taken individually has
preferably an apparent density ranging from 0.10 to 1.80.
[0075] According to an embodiment, the fillers have an apparent
density ranging from 0.60 to 1.80 and each filler taken
individually has an apparent density ranging from 0.10 to 1.80.
Indeed, it is possible to provide a mixture of at least two
fillers, at least one filler having an apparent density ranging
from 0.10 to 1.00 and at least one filler having an apparent
density higher than 1.00 and less than or equal to 1.80.
[0076] The apparent density is measured by standard methods well
known to a person skilled in the art, for example by weighing a
determined volume as described in the experimental part of the
present invention. The apparent density is defined by the ratio of
the mass of the material to the apparent volume of all of the
particles.
[0077] The presence of the filler makes it possible to control and
increase the thickness of the peelable adhesive film without
increasing its cost. A greater thickness increases the cohesion of
the film and facilitates its removal after drying.
[0078] According to an embodiment of the present invention, the
filler is a mineral filler. Preferably the filler is selected from
calcium carbonate, magnesium carbonate, sand, alumina, hydrated
alumina, magnesium silicate, aluminium silicate, sodium silicate,
potassium silicate, mica and silica. More particularly, the filler
is selected from calcium carbonate and sand.
[0079] It is also possible to envisage the use of one or more
organic fillers, alone or in combination with one or more mineral
fillers.
[0080] The natural latex represents from 30% to 45% by weight of
dry matter with respect to the total weight of the adhesive
composition, preferably from 30% to 40% by weight of dry matter
with respect to the total weight of the adhesive composition, yet
more preferably from 31% to 38% by weight of dry matter with
respect to the total weight of the adhesive composition.
[0081] The polymer composition represents from 5 to 40% by weight
of dry matter with respect to the total weight of the adhesive
composition, from 6% to 25% by weight of dry matter with respect to
the total weight of the adhesive composition, yet more preferably
from 10% to 20% by weight of dry matter with respect to the total
weight of the adhesive composition.
[0082] According to an embodiment, the ratio (m/m) of the mass of
latex (dry mass) to the mass of polymer composition (dry matter)
ranges from 0.75 to 4.5, preferably from 1.2 to 2.5.
[0083] According to an embodiment, the filler(s) represent(s) from
15% to 35% by weight of the total weight of the adhesive
composition, preferably from 20% to 30% by weight of the total
weight of the adhesive composition.
[0084] In the adhesive composition, water is contributed by the
latex, by the aqueous emulsion of copolymer or mixture of polymers
and by an optional addition of water. In fact, depending on the
dilution of the copolymer or of the mixture of polymers, water may
be added in order to obtain the desired concentration of active
material.
[0085] According to an embodiment, the water represents from 20% to
60% by weight of the total weight of the adhesive composition,
preferably from 30% to 50% by weight of the total weight of the
adhesive composition.
[0086] According to an embodiment of the invention, the peelable
adhesive composition comprises one or more other additives chosen
from: a thickening agent, a biocide, an antifoaming agent, a latex
stabilizer, an odour-masking agent, a pH adjusting agent and/or an
antioxidant.
[0087] The thickening agent makes it possible in particular to hold
the filler(s) in suspension.
[0088] Preferably, the thickening agent is an aqueous solution of
sodium polyacrylate or an aqueous solution of polyurethane.
Generally the thickening agent has a glass transition temperature
of the order of 200.degree. C., well above the glass transition
temperatures of the copolymers or of the mixtures of polymers
defined previously.
[0089] Preferably, the thickening agent represents from 0.1 to 5%,
preferably from 0.5% to 5% by weight of the total weight of the
adhesive composition.
[0090] Preferably the other additives represent from 0.5% to 5% by
weight of the total weight of the adhesive composition.
[0091] Preferably, the polymer composition has a glass transition
temperature (Tg) ranging from -40.degree. C. to -10.degree. C.,
more particularly from -37.degree. C. to -15.degree. C. In a
standard manner, well known to a person skilled in the art, the
glass transition temperature can be measured by DSC (Differential
Scanning calorimetry).
[0092] By copolymer comprising at least one (meth)acrylate or
(meth)acrylic monomer, is meant a polymer formed from at least two
monomers, including a (meth)acrylate or (meth)acrylic monomer.
[0093] By mixture of polymers comprising at least one
(meth)acrylate or (meth)acrylic monomer, is meant a mixture
comprising at least two polymers of which at least one polymer is
formed from (meth)acrylate or (meth)acrylic monomers.
[0094] According to an embodiment, the (meth)acrylate or
(meth)acrylic monomer is chosen from acrylic acid, methacrylic
acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl
methacrylate, butyl acrylate, butyl methacrylate, isobutyl
acrylate, isobutyl methacrylate, n-hexyl acrylate, n-hexyl
methacrylate, ethyl hexyl acrylate, ethylhexyl methacylate,
n-heptyl acrylate, n-heptyl methacrylate, stearyl acrylate, stearyl
methacrylate, glycidyl methacrylate, acrylamide, methacrylamide,
hydroxyethyl acrylate, hydroxyethyl methacrylate, allyl
methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate,
2-ethoxyethyl-acrylate, 2-ethoxyethyl-methacrylate, isodecyl
acrylate, isodecyl methacrylate, 2-methoxy acrylate,
2-ethoxy-methacrylate, 2-(2-ethoxyethoxy)-ethylacrylate,
2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, isobomyl
acrylate, isobomyl methacrylate, caprolactone acrylate,
caprolactone methacrylate, polypropylene glycol monoacrylate,
polypropylene glycol monomethacrylate, polyethylene glycol
acrylate, polyethylene glycol methacrylate, benzyl acrylate, benzyl
methacrylate.
[0095] According to a particular embodiment of the invention, the
polymer composition having a glass transition temperature ranging
from -50.degree. C. to 0.degree. C. comprises at least one
copolymer or a mixture of at least two polymers comprising at least
one (meth)acrylate or (meth)acrylic monomer.
[0096] According to a particular embodiment of the invention, the
polymer composition having a glass transition temperature ranging
from -50.degree. C. to 0.degree. C. consists essentially of one or
more copolymers or a mixture of at least two polymers comprising at
least one (meth)acrylate or (meth)acrylic monomer.
[0097] According to an embodiment, the copolymer or the mixture of
polymers comprising at least one (meth)acrylate or (meth)acrylic
monomer comprises one or more other monomers chosen from vinyl
acetate, ethylene, styrene, vinyl chloride, vinyl versatate and
vinyl laurate.
[0098] According to an embodiment, the copolymer comprising at
least one (meth)acrylate or (meth)acrylic monomer is a vinyl
acetate, ethylene and acrylate terpolymer.
[0099] According to an embodiment of the invention, the polymer
composition having a glass transition temperature ranging from
-50.degree. C. to 0.degree. C. comprises at least one mixture of at
least two polymers comprising at least one polyester and at least
one polyurethane.
[0100] Preferably, the polymer composition consists essentially of
a mixture of polyesters and polyurethanes.
[0101] According to an embodiment, the polyurethanes are obtained
from at least one polyol and at least one polyisocyanate.
[0102] Advantageously, the polyols are chosen from ethylene glycol,
1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol,
1,3-butanediol, 1,4-butenediol, 1,4-butynediol, 1,5-pentanediol,
1,6-hexanediol, 1, 8-octanediol, neopentylglycol,
cyclohexanedimethanol, 2-methyl-1,3-propanediol, 1,5-pentanediol,
diethylene glycol, triethylene glycol, tetraethylene glycol,
polyethylene glycol, dipropylene glycol, polypropylene glycol,
dibutylene glycol and polybutylene glycol.
[0103] Preferably, the polyisocyanates are chosen from the linear
or branched diisocyanates comprising an alkylene chain of 4 to 14
carbon atoms, cycloaliphatic diisocyanates comprising from 6 to 12
carbon atoms, aromatic diisocyanates comprising from 8 to 14 carbon
atoms, polyisocyanates comprising isocyanurates, uretdione
diisocyanates, diisocyanates comprising biurets, polyisocyanates
comprising urethane and/or allophanate groups, polyisocyanates
comprising oxadiazinetrione groups, uretonimine-modified
polyisocyanates, or mixtures thereof.
[0104] According to an embodiment, the diisocyanates are chosen
from tetramethylene diisocyanate, hexamethylene diisocyanate,
octamethylene diisocyanate, decamethylene diisocyanate,
dodecamethylene diisocyanate, tetradecamethylene diisocyanate,
trimethylhexane diisocyanate, tetramethylhexane diisocyanate,
1,4-diisocyanatocyclohexane, 1,3-diisocyanatocyclohexane,
1,2-diisocyanatocyclohexane, 4.4'-di(isocyanatocyclohexyl)methane,
1,4-diisocyanatocyclohexene, 1,3-diisocyanatocyclohexene,
1,2-diisocyanatocyclohexene, isophorone diisocyanate (IPDI),
2,4-diisocyanato-1-methylcyclohexane,
2,6-diisocyanato-1-methylcyclohexane, 2,4-diisocyanatotoluene,
2,6-diisocyanatotoluene, tetramethylxylylene diisocyanate,
1,4-diisocyanatobenzene, 4.4'-diisocyanatodiphenylmethane,
2,4-diisocyanatodiphenylmethane, p-xylylene diisocyanate and
isopropenyldimethyltolylene diisocyanate.
[0105] According to an embodiment, the polyesters are chosen from
the polyol polyesters. Preferably, the polyesters are obtained from
polycarboxylic acids and/or polycarboxylic anhydrides and/or
polycarboxylates and polyols.
[0106] The polycarboxylic acids can be aliphatic, cycloaliphatic,
aromatic or heterocyclic, they can be unsubstituted or substituted,
for example with a halogen, and they can be saturated or
unsaturated.
[0107] According to an embodiment, the polycarboxylic acids, the
polycarboxylic anhydrides are chosen from succinic acid, adipic
acid, suberic acid, azelaic acid, sebacic acid, phthalic acid,
isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride,
hexahydrophthalic anhydride, tetrachlorophthalic anhydride,
endomethylenetetrahydrophthalic anhydride, glutaric anhydride,
maleic acid, maleic anhydride, fumaric acid.
[0108] Among the polyols which can be used for manufacturing the
polyester, ethylene glycol, 1,2-propylene glycol, 1,3-propylene
glycol, 1,4-butanediol, 1,3-butanediol, 1,4-butenediol,
1,4-butynediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol,
neopentylglycol, cyclohexanedimethanol, 2-methyl-1,3-propanediol,
1,5-pentanediol, diethylene glycol, triethylene glycol,
tetraethylene glycol, polyethylene glycol, dipropylene glycol,
polypropylene glycol, dibutylene glycol and polybutylene glycol may
be mentioned.
[0109] According to an embodiment of the invention, the polymer
composition having a glass transition temperature ranging from
-50.degree. C. to 0.degree. C. comprises at least one vinyl acetate
and ethylene copolymer.
[0110] According to an embodiment of the invention, the polymer
composition having a glass transition temperature ranging from
-50.degree. C. to 0.degree. C. comprises a mixture of: [0111] at
least one copolymer or a mixture of at least two polymers
comprising at least one (meth)acrylate or (meth)acrylic monomer as
defined above, and [0112] at least one mixture of at least two
polymers comprising at least one polyester and at least one
polyurethane as defined above.
[0113] According to an embodiment of the invention, the polymer
composition having a glass transition temperature ranging from
-50.degree. C. to 0.degree. C. consists essentially of a mixture
of: [0114] one or more copolymers or a mixture of at least two
polymers comprising at least one (meth)acrylate or (meth)acrylic
monomer as defined above, and [0115] a mixture of at least one
polyester and at least one polyurethane as defined above.
[0116] According to an embodiment of the invention, the fillers
have an apparent density ranging from 0.60 to 1.80, preferably from
1.30 to 1.70, more preferably from 1.40 to 1.60.
[0117] As indicated previously, it is possible to provide a mixture
of several fillers, said mixture having an apparent density ranging
from 0.60 to 1.80, preferably from 1.30 to 1.70, more preferably
from 1.40 to 1.60, each filler taken individually having an
apparent density ranging from 0.10 to 1.80.
[0118] Preferably, the filler has a particle size ranging from 10
to 400 um.
[0119] A person skilled in the art can adjust the proportions and
the selection of the monomers in order to obtain a copolymer or a
mixture of polymers having the desired glass transition
temperature.
[0120] The emulsions of (co)polymer(s) which can be used for the
preparation of the adhesive composition of the invention are
commercially available. The following products may be mentioned:
[0121] PLEXTOL.RTM. D 306 (available from Synthomer): aqueous
dispersion of pure acrylic resin based on n-butylacrylate (98%) and
styrene (2%) having a glass transition temperature of -30.degree.
C., [0122] VINNAPAS.RTM. EAF 68 (available from Wacker): aqueous
dispersion of acrylic resin based on vinyl acetate, ethylene and
acrylate having a glass transition temperature of -35.degree. C.,
[0123] ACRONAL.RTM. A 380 (available from BASF): aqueous dispersion
of acrylic resin based on acrylate(s) and acrylonitrile having a
glass transition temperature of -22.degree. C., [0124] LUPHEN.RTM.
D DS 3548 (available from BASF): dispersion of a resin based on
ester and urethane having a glass transition temperature of
-46.degree. C., [0125] VINNAPAS.RTM. EP 8010 (available from
Wacker): Aqueous dispersion of resin based on vinyl acetate (83%)
and ethylene (17%) having a glass transition temperature of
-10.degree. C.
[0126] According to an embodiment of the invention, the peelable
adhesive composition also comprises fibres such as cellulose
fibres, glass fibres, rubber fibres, natural fibres, such as
cotton, viscose, jute, sisal or synthetic fibres such as polyamide,
polyester, polyacrylonitrile, polypropylene polyethylene.
Preferably, the fibres represent from 0.01 to 2% by weight with
respect to the weight of the peelable adhesive composition.
[0127] The fibres make it possible, after drying of the
composition, to increase the cohesion of the membrane (or film)
thus obtained.
[0128] According to an embodiment of the invention, the adhesive
composition also comprises up to 10% by weight of a tackifying
resin, preferably selected from the colophane esters, terpene
resins, phenolic terpene resins and dispersions based on phenolic
terpene resin.
[0129] The tackifying resin makes it possible to improve the
trapping nature of the adhesive. This makes it possible to better
hold the materials together once assembled, so that they do not
slip and do not move relative to one another. Thus, the adhesive
film remains continuous and immobile throughout the setting period
and the bonding does not open up.
[0130] Another subject of the present invention is a method for
manufacturing the peelable adhesive according to the invention. The
peelable adhesive is manufactured by simple mixing of the
components. Preferably, the latex is added first and the thickening
agent last. After manufacture, the adhesive composition is stored
away from light and air at a temperature ranging from 5.degree. C.
to 40.degree. C., preferably from 10.degree. C. to 30.degree.
C.
[0131] In the case where the copolymer or mixture of polymers is in
the form of a redispersible powder, the copolymer or mixture of
polymers is incorporated into the adhesive composition by adding
more water in order to obtain an aqueous solution.
[0132] Another subject of the present invention relates to a
membrane obtained by drying of the peelable adhesive composition
according to the invention.
[0133] In fact, the peelable adhesive composition according to the
invention can be applied onto a substrate, for example the floor,
then after drying of said adhesive composition, the latter forms a
peelable membrane.
[0134] According to an embodiment, the peelable membrane has a
thickness greater than or equal to 100 .mu.m, preferably greater
than or equal to 125 .mu.m, more particularly greater than or equal
to 150 .mu.m. A person skilled in the art can adapt the maximum
thickness depending on the conditions of implementation. In fact,
it is desirable not to have too great a thickness for a surface
covering adhesive bonded onto a substrate. More particularly, the
thickness of the peelable membrane (or film) may be less than or
equal to 1 millimetre.
[0135] According to an embodiment of the invention, the peelable
membrane can be obtained by application of the peelable adhesive
composition according to the invention to a weft or a non-woven
reinforcing tape.
[0136] Preferably, the weft is in the form of a mesh of a woven or
non-woven material. The material constituting the weft can be a
metal, natural or synthetic fibres or a plastic or in the form of a
woven or non-woven reinforcing tape.
[0137] A weft made of glass fibre, of polyamide, a metal grid, a
non-woven material obtained by fusion of interlaced polypropylene
or polyethylene fibres, a woven polyester material may be
mentioned
[0138] According to an embodiment, a covering is applied directly
to the peelable membrane. In this case, the substrate and the
covering can be unstuck and, after unsticking, have intact
surfaces, i.e. free of adhesive residue after removal of the
covering.
[0139] In the case where a weft is used, the bonding is reinforced
and the removal of the membrane from the surface of the covering
and from the surface of the substrate is facilitated.
[0140] According to an embodiment, the weft is coated with adhesive
(pre-glued weft ready for use), i.e. it comprises an adhesive
composition, for example an adhesive composition of PSA (pressure
sensitive adhesive) type, i.e. a hot melt adhesive composition or
an acrylic adhesive composition or an adhesive composition based on
poly(styrene-isoprene-styrene) or an adhesive composition based on
poly(styrene-butadiene-styrene). According to this embodiment, the
weft is coated with an adhesive composition different from the
peelable adhesive composition according to the invention. According
to this embodiment, the weft is better held on the floor, which
facilitates the subsequent application of the peelable adhesive
composition according to the invention.
[0141] Another subject of the present invention is the combination
of a flexible surface covering with a peelable adhesive composition
according to the invention.
[0142] In fact, it may be wise to combine, in a kit intended for
professionals or private individuals, a flexible surface covering
and an adhesive composition in quantities suited to the surface to
be covered.
[0143] A weft may also form part of the kit.
[0144] The flexible surface coverings used in the invention are
those which satisfy the conditions laid down in the standards DTU
53.1 and 53.2.
[0145] The adhesive composition according to the present invention
is quite particularly suitable for bonding and holding flexible
surface coverings having a high dimensional variability, preferably
flexible surface coverings having a maximum dimensional variability
greater than or equal to 0.2%, preferably greater than or equal to
0.3%, preferably ranging from 0.3% to 1%, yet more preferably
ranging from 0.4 to 0.8%.
[0146] The maximum dimensional variability of the covering is
measured according to the Freudenberg test as described in the
experimental part. The maximum dimensional variability corresponds
to the maximum dimensional variation value measured in one of the
directions AB, AC, CD or BD (see FIG. 5).
[0147] Among the coverings with high dimensional variability which
can be utilized in the present invention, the coverings made of
rubber or luxury vinyl tiles or laminates (LVT) may be
mentioned.
[0148] However, the adhesive composition according to the present
invention can be used for bonding and holding other types of
coverings, such as carpets or polymer floor coverings, for example
made of PVC, or linoleum coverings. More particularly rubber tiles
or rolls may be mentioned.
[0149] Among these types of coverings, knitted, tufted, woven and
flocked carpets, in rolls or in tiles, may be mentioned, in
particular those which meet the requirements of NF EN 1307, as well
as needled floor coverings in rolls or in tiles, in particular
those which meet the requirements of NF EN 1470 and prEN 13297.
Conventional wool or synthetic carpets, and natural-fibre coverings
may be mentioned.
[0150] Among the polymer coverings, the following examples may be
mentioned (see the standard DTU 53.2): [0151] homogeneous and
heterogeneous floor coverings based on polyvinyl chloride [0152]
floor coverings based on polyvinyl chloride on a jute or polyester
support or on a polyester support with a polyvinyl chloride back
[0153] floor coverings based on polyvinyl chloride on foam [0154]
floor coverings based on polyvinyl chloride with cork-based support
[0155] floor coverings based on expanded polyvinyl chloride [0156]
Semi-flexible tiles based on polyvinyl chloride [0157]
Cork-agglomerate tiles with a wear layer based on polyvinyl
chloride [0158] Flexible coverings based on polymers of renewable
origin (of agricultural origin in particular) such as PLA
(polylactic acid) or polyolefin polymers (the olefin originating in
particular from bio-ethanol).
[0159] It is therefore possible to use in the invention a large
number of different coverings, for example the following coverings:
[0160] homogeneous P.V.C. (tiles or rolls) [0161] multilayer P.V.C.
(tiles or rolls) [0162] P.V.C. on cork [0163] Polyolefins [0164]
Linoleum rolls [0165] Rubbers in tiles or rolls [0166] Expanded
relief vinyls (E.R.V.) [0167] Semi-flexible tiles [0168] Needled
coverings with or without back [0169] Carpets on foam (latex)
[0170] Carpets with non-woven back [0171] Carpets with synthetic
backs (Action Back type) [0172] Coconut, sisal and seagrass with
latexed back.
[0173] Another subject of the invention relates to a method for
applying a flexible surface covering onto a substrate comprising
the following steps: [0174] a) applying a layer of peelable
adhesive composition according to the invention onto the substrate,
[0175] b) adhering the flexible surface covering onto the
substrate.
[0176] The substrate to which the covering of the invention is
applied is any conventional support receiving this type of
covering. For example surfaced concretes (in particular with a
finished facing), cement-based screeds (incorporated or added),
anhydrite screeds, levellers, old (previous) tiles, suitable
smoothed old (previous) parquet flooring, chipboard or plywood
panels, conventional wall facings may be mentioned.
[0177] Adhering the flexible surface covering onto the substrate
corresponds to the action of applying or placing the covering on
the substrate covered with the layer of peelable adhesive
composition.
[0178] According to a preferred embodiment, the flexible surface
covering is a covering with high dimensional variability,
preferably a flexible surface covering having a maximum dimensional
variability greater than or equal to 0.2%, preferably greater than
or equal to 0.3%, preferably ranging from 0.3% to 1%, yet more
preferably ranging from 0.4 to 0.8%, measured according to the
Freudenberg test described in the experimental part.
[0179] Preferably, the flexible surface covering is chosen from the
coverings made of rubber and luxury vinyl tiles or laminates
(LVTs).
[0180] According to an embodiment of the invention, the quantity of
peelable adhesive composition is greater than or equal to 250
g/m.sup.2, preferably greater than or equal to 300 g/m.sup.2, more
particularly greater than or equal to 350 g/m.sup.2.
[0181] The application of the peelable adhesive composition onto
the substrate is carried out continuously or discontinuously.
[0182] Preferably, the layer of adhesive is applied directly onto
the substrate. The substrate is generally not primed before
application of the layer of adhesive. For example a tile floor
undergoes simple scraping before application of the layer of
adhesive. The substrates are those mentioned in the standard DTU
53.1.
[0183] In a standard manner, the flexible surface covering is laid
after satisfying a gumming time ranging from 10 to 45 minutes. The
gumming time corresponds to the period during which the adhesive
composition applied thickens and increases its adhesion.
[0184] Preferably, the application method of the invention has an
additional step c) of roller-pressing in order to facilitate the
transfer of the adhesive to the back of the flexible covering. This
step makes it possible in particular to spread the adhesive
composition in order to make the adhesive composition applied
continuous or substantially continuous on the substrate.
[0185] The user can lay the flexible covering within a time
interval defined by the working time which is of the order of 30
minutes and which can be modulated by the addition of additives.
The working time starts to run at the end of the gumming time and
ends at the moment when the adhesive has lost its adhesive
character.
[0186] After drying of the adhesive composition, a film (also
called a membrane) of peelable adhesive is obtained.
[0187] According to an embodiment, the peelable adhesive film or
membrane has a thickness greater than or equal to 100 .mu.m,
preferably greater than or equal to 125 .mu.m, more particularly
greater than or equal to 150 .mu.m. A person skilled in the art can
adapt the maximum thickness depending on the conditions of
implementation. In fact, it is desirable not to have too great a
thickness for a surface covering bonded onto a substrate. More
particularly, the thickness of the peelable adhesive film can be
less than or equal to 1 millimetre.
[0188] The invention applies preferentially to floor coverings, but
can also be applicable to walls.
[0189] According to a particular embodiment of the method of
application of a flexible surface covering according to the
invention, a weft is placed on the substrate before step a) of
applying the layer of peelable adhesive composition.
[0190] Preferably, the weft is in the form of a mesh, of a woven or
non-woven material or of a non-woven reinforcing tape.
[0191] The material constituting the weft can be a metal, natural
or synthetic fibres or a plastic.
[0192] For example, a weft made of glass fibre, polyamide, a metal
grid, a non-woven material obtained by fusion of interlaced
polypropylene or polyethylene fibres, a woven polyester material
may be mentioned.
[0193] FIG. 3 illustrates a particular embodiment of the invention.
FIG. 3a shows in perspective the initial substrate 3. FIG. 3b shows
in perspective the substrate 3 on which a weft 5 is placed. FIG. 3c
shows in perspective the substrate 3 covered by the weft 5 to which
the adhesive composition 1 is applied using an applicator 6. FIG.
3d shows in cross-section the substrate 3 covered by the adhesive
composition 1. The weft 5 is then impregnated with the adhesive
composition 1. Then, a flexible covering 2 is applied onto the
adhesive composition 1 comprising the weft 5, as illustrated in
FIG. 3e.
[0194] Alternatively, the weft can be pre-glued with an adhesive
composition, different from the peelable adhesive composition
according to the invention, for example with an adhesive
composition of PSA type, i.e. a thermofusible adhesive composition
or an acrylic adhesive composition or an adhesive composition based
on poly(styrene-isoprene-styrene) or an adhesive composition based
on poly(styrene-butadiene-styrene) etc. Preferably, the application
method is followed by an additional step c) of roller-pressing.
[0195] Another subject of the present invention is a substrate
covered with the peelable film according to the invention and the
flexible surface covering.
[0196] FIG. 1 represents the flexible covering 2 bonded onto a
substrate 3 by means of the peelable adhesive 1 according to the
invention.
[0197] Another subject of the present invention is a method for
renovating a substrate comprising a surface covering, this method
comprising a step of lifting a flexible covering according to the
invention.
[0198] The lifting of the surface covering corresponds to the
action of stripping away, taking off, unsticking or pulling away
the covering.
[0199] The lifting step is carried out by exerting a pealing force
on the covering so that the layer constituted by the peelable
adhesive film at the peelable film/substrate and peelable
film/flexible covering interface pulls away easily, leaving the
substrate and the flexible covering as they were before the
bonding.
[0200] The renovation method according to an embodiment of the
invention makes it possible to obtain a substrate and a flexible
covering both free from adhesive residues (FIG. 2). The failure,
shown diagrammatically in FIG. 2 by the lines 4, is adhesive.
[0201] According to an embodiment of the invention, the renovation
method comprises an additional step of recycling the flexible
covering.
[0202] After lifting the flexible covering, the substrate can
immediately be re-covered with a new covering and the covering can
be recycled.
[0203] Another subject of the present invention relates to the use
of the adhesive composition according to the invention for holding
a flexible surface covering having a maximum dimensional
variability measured according to the Freudenberg test greater than
or equal to 0.2%.
[0204] The adhesive composition according to the invention
effectively makes it possible to hold the flexible surface
coverings having a high dimensional variability. As indicated in
the experimental part, the covering bonded onto a substrate using
the adhesive composition according to the invention produces an
overall variation (as defined in the experimental part and
calculated in Table 2) less than or equal to 0.10%.
[0205] Without further elaboration, it is believed that one skilled
in the art can, using the preceding description, utilize the
present invention to its fullest extent. The preceding preferred
specific embodiments are, therefore, to be construed as merely
illustrative, and not limitative of the remainder of the disclosure
in any way whatsoever.
[0206] In the foregoing and in the examples, all temperatures are
set forth uncorrected in degrees Celsius and, all parts and
percentages are by weight, unless otherwise indicated.
[0207] The entire disclosures of all applications, patents and
publications, cited herein and of corresponding French application
No. 14/55.130, filed Jun. 5, 2014, are incorporated by reference
herein.
EXAMPLES
[0208] Different adhesive compositions were prepared and the
performances of these compositions were tested.
[0209] The compositions A, B and C are according to the document
EP2610317 and do not form part of the invention.
[0210] The compositions 1 and 2 are peelable adhesive compositions
according to the present invention.
[0211] The following copolymers were used: [0212] VINNAPAS.RTM. EAF
68: Aqueous dispersion of acrylic resin based on vinyl acetate,
ethylene and acrylate with Tg=-35.degree. C., [0213] LUPHEN.RTM. D
DS 3548 (available from BASF): dispersion of a resin based on ester
and urethane having a glass transition temperature of -46.degree.
C.
[0214] The natural latex used in the examples is a natural latex
Ulacol.RTM.--3 available from Thai Regitex Co, Ltd, comprising 60%
dry extract.
[0215] The apparent density of the fillers was measured according
to the following procedure: [0216] a cup with a capacity of
approximately V=500 ml, calibrated (mass of the cup Mo=500 g), is
put in position directly below a stainless steel funnel with a
capacity of approximately 600 ml; [0217] the hollow bottom of the
funnel is closed with a slide, the slide making it possible to
ensure the opening and closing of the hollow bottom of the funnel);
[0218] the funnel is completely filled with the homogenized
filler(s), and the slide is rapidly removed, thus allowing the
filler(s) to flow into the cup; [0219] the superfluous fillers are
slowly levelled off using a flat rule (an equivalent instrument may
be suitable), and the outside of the cup is carefully cleaned with
a dry cloth (a brush can be used), [0220] the cup is placed on an
analytical balance accurate to 0.1 g and the cup and its content,
mass M1, are weighed with an accuracy of 0.1 g.
[0221] The apparent density is then calculated as being:
d=(M1-Mo)/V. In this formula, M1 and Mo are expressed in grams, the
volume is expressed in cm.sup.3.
[0222] The compositions illustrated in the experimental part are
described in Table 1 below.
TABLE-US-00001 TABLE 1 Compositions Composition (% by weight) A B C
1 2 VINNAPAS .RTM. EAF 68 (% dry 9.00 9.00 9.00 9.00 4.20 weight)
LUPHEN .RTM. D DS 3548 (% dry 3.60 3.60 3.60 3.60 1.80 weight)
Natural latex (% dry weight) 6.00 18.00 28.00 30.00 45.00 water
56.20 45.50 34.20 32.20 34.00 Filler CaCO.sub.3 350 .mu.m 22.05
20.85 22.05 22.05 11.80 apparent density of the fillers 1.7 1.7 1.7
1.7 1.7 thickening agent: aqueous solution of 0.80 0.80 0.80 0.80
0.80 sodium polyacrylate Biocide BT .RTM. 20 0.11 0.11 0.11 0.11
0.11 pH adjuster -30% soda 0.17 0.17 0.17 0.17 0.17 20% N
stabilizer (fatty alcohol 1.30 1.30 1.30 1.30 1.30 polyglycol
ether) Filler dispersant Ecodis .RTM. P 90 0.15 -- 0.15 0.15 0.15
(ammonium polyacrylate) Anti-UV Aquanox .RTM. LSF 0.35 0.35 0.35
0.35 0.35 Anti-foam Foamaster .RTM. NXZ 0.20 0.20 0.20 0.20
0.20
Dimensional Variability of the Bonded Covering
[0223] The dimensional variability of a rubber-type covering is
assessed with the Freudenberg test. The rubber used is a Nora
covering with a thickness of 2 mm
[0224] FIG. 5a is a diagrammatic representation of the device used
for the Freudenberg test. The component 51 represents the
thermostat, the component 52 represents a ceramic heating element,
the component 53 represents the test specimen and the component 54
represents the support on which the specimen is positioned.
[0225] The preparation of the specimens is carried out in
accordance with the standard EN 1903: [0226] the adhesive
composition tested is applied to a fibrocement-type substrate,
[0227] the covering made of rubber measuring 25 cm.times.25 cm is
applied onto the adhesive composition after a gumming time of 15
minutes, [0228] reference points are bonded onto the covering at
points A, B, C and D (see FIG. 5b), [0229] the distance between the
points AB, CD, AC and BD is measured, [0230] the specimen is then
placed at ambient temperature (23.degree. C.) for 24 hours, and is
then placed under infra-red irradiation (the temperature is then
50.degree. C. at the surface of the covering) for 4 hours, [0231]
the distance between the plots AB, CD, AC and BD is then
immediately measured (variation X), [0232] the specimen is then
placed at ambient temperature (23.degree. C.) for 24 hours, [0233]
the distance between the plots AB, CD, AC and BD is then measured
(variation Y).
[0234] The measurement of the distances AB and CD assesses the
cross-sectional variation and the measurement of the distances AC
and BD assesses the longitudinal variation. FIG. 5b shows the
positions of the points A, B, C and D on the test piece. The arrow
represents the longitudinal direction of the covering made of
rubber.
[0235] The variation in the covering alone, i.e. covering not
bonded to the substrate, is:
AB/CD/AC/BD=0.54%/0.54%/0.26%/0.24%.
[0236] The maximum dimensional variability of the covering is the
maximum variation measured in one of the directions according to
the Freudenberg test. For the tested covering made of rubber, the
maximum dimensional variability is 0.54%.
[0237] As an indication, a dimensional variation of 0.1% in one
direction means that for a 1 metre length, there will be a 1 mm
variation in the covering and this will therefore be visible at the
joints of the covering.
[0238] The Freudenberg test results are shown in Table 2 below.
[0239] To facilitate comparison between the different adhesive
compositions, the overall variation in the covering thus indicated
in Table 2 is calculated as follows: Absolute value (maximum
variation X) +absolute value (maximum variation Y)
TABLE-US-00002 TABLE 2 Dimensional variation in % measured by the
Freudenberg test Variation X Variation Y Overall (24 h to
23.degree. C. (24 h at 23.degree. C., 4 h at 50.degree. C.
variation and 4 h at 50.degree. C.) and 24 h at 23.degree. C.) in
the AB CD AC BD AB CD AC BD covering A 0.14 0.12 0.14 0.13 -0.10
-0.10 -0.11 -0.09 0.24% B 0.12 0.12 0.11 0.10 -0.08 -0.07 -0.07
-0.08 0.20% C 0.10 0.10 0.10 0.09 -0.04 -0.05 -0.04 -0.05 0.15% 1
0.06 0.06 0.05 0.06 -0.04 -0.03 -0.03 -0.03 0.10% 2 0.01 0.02 0.01
0.02 -0.02 -0.02 -0.03 -0.02 0.03%
[0240] In the light of Table 2, it is clear that the overall
dimensional variation of the covering bonded with an adhesive
composition according to the invention (Examples 1 and 2) is 0.10%
and 0.03% respectively whereas the overall dimensional variation of
the covering bonded with an adhesive composition as described in
the document EP2610317 varies from 0.15% to 0.24%.
[0241] If the overall variation is greater than 0.10%, this means
that the adhesive composition does not hold the covering made of
rubber sufficiently and lifting up or opening phenomena at the
joints of the covering are possible. FIG. 4 shows this bulging and
blistering phenomenon at the joints of a covering (see the circle
drawn in FIG. 4).
[0242] Moreover, the bonding and lifting efficiencies described in
the document EP2610317 are retained or even improved by means of
the compositions according to the present invention.
[0243] The preceding examples can be repeated with similar success
by substituting the generically or specifically described reactants
and/or operating conditions of this invention for those used in the
preceding examples.
[0244] From the foregoing description, one skilled in the art can
easily ascertain the essential characteristics of this invention
and, without departing from the spirit and scope thereof, can make
various changes and modifications of the invention to adapt it to
various usages and conditions.
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