U.S. patent application number 14/901930 was filed with the patent office on 2016-06-16 for coated glass fibre mesh fabric with reduced gross heat of combustion.
This patent application is currently assigned to SAINT-GOBAIN ADFORS. The applicant listed for this patent is SAINT-GOBAIN ADFORS. Invention is credited to Petr HELEMIK, Lukas KULHAVY, Bohuslav MIKULECKY.
Application Number | 20160168782 14/901930 |
Document ID | / |
Family ID | 48700433 |
Filed Date | 2016-06-16 |
United States Patent
Application |
20160168782 |
Kind Code |
A1 |
MIKULECKY; Bohuslav ; et
al. |
June 16, 2016 |
COATED GLASS FIBRE MESH FABRIC WITH REDUCED GROSS HEAT OF
COMBUSTION
Abstract
The invention is drawn to a glass fiber mesh fabric coated with
an organic polymer coating having a reduced gross heat of
combustion (less than 3.0 MJ/kg), said polymer coating comprising
(i) from 60 wt % to 99.9 wt % of poly(vinylidene chloride) (PVDC)
or a copolymer thereof; and (ii) from 0.1 wt % to 40 wt % of a
formaldehyde-based resin selected from melamine-formaldehyde
resins, phenol-formaldehyde resins, urea-formaldehyde resins or a
combination thereof. The invention also provides a method for
producing such a coated glass fiber mesh fabric.
Inventors: |
MIKULECKY; Bohuslav; (Usti
nad Orlici, CZ) ; HELEMIK; Petr; (Svitavy, CZ)
; KULHAVY; Lukas; (Nove Hrady, CZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAINT-GOBAIN ADFORS |
Chambery |
|
FR |
|
|
Assignee: |
SAINT-GOBAIN ADFORS
Chambery
FR
|
Family ID: |
48700433 |
Appl. No.: |
14/901930 |
Filed: |
July 1, 2014 |
PCT Filed: |
July 1, 2014 |
PCT NO: |
PCT/EP14/63969 |
371 Date: |
December 29, 2015 |
Current U.S.
Class: |
442/1 ;
427/389.8 |
Current CPC
Class: |
D06M 15/248 20130101;
C03C 25/1095 20130101; D04H 13/00 20130101; C03C 25/34 20130101;
C03C 25/30 20130101; D04H 1/4218 20130101 |
International
Class: |
D06M 15/248 20060101
D06M015/248 |
Claims
1. A glass fiber mesh fabric coated with an organic polymer
coating, wherein the organic polymer coating comprises: (i) from 60
wt % to 99.9 wt % of a poly(vinylidene chloride) (PVDC) or a
copolymer thereof; and (ii) from 0.1 wt % to 40 wt % of a
formaldehyde-based resin selected from the group consisting of a
melamine-formaldehyde resin, a phenol-formaldehyde resin, a
urea-formaldehyde resin and a combination thereof.
2. The coated glass fiber mesh fabric according to claim 1,
comprising from 6 wt % to 20 wt % of the organic polymer coating,
measured as loss on ignition (LOI), relative to a total weight of
the coated glass fiber mesh.
3. The coated glass fiber mesh fabric according to claim 1, wherein
the organic polymer coating comprises from 0.1 to 10 wt % of the
melamine-formaldehyde resin or the phenol-formaldehyde resin or the
urea-formaldehyde resin or a combination thereof.
4. The coated glass fiber mesh fabric according to claim 1, wherein
the organic polymer coating comprises a poly(vinylidene chloride)
copolymer comprising from 75 to 98 wt % of vinylidene chloride
monomer units and from 2 to 25 wt % of at least one comonomer
selected from the group consisting of methyl acrylate, ethyl
acrylate, butyl acrylate, methyl methacrylate, acrylonitrile,
methacrylonitrile, an unsaturated carboxylic acid and vinyl
chloride.
5. The coated glass fiber mesh fabric according to claim 1, having
a gross heat of combustion (PCS) of less than 3.5 MJ/kg (according
to EN ISO 1716:2010).
6. The coated glass fiber mesh fabric according to claim 1, wherein
the organic polymer coating further comprises from 0.1 to 40 wt %
of an organic polymer having a T.sub.g lower than 40.degree. C.
7. The coated glass fiber mesh fabric according to claim 6, wherein
the organic polymer having a T.sub.g lower than 40.degree. C. is
selected from the group consisting of a polyacrylates, a
polymethacrylate, a styrene-butadiene copolymer, a styrene-acrylate
copolymer, a poly(vinyl acetate) and a poly(ethylene vinylacetate)
copolymer.
8. A method for producing the coated glass fiber mesh of claim 1,
the method comprising: (a) impregnating a woven or knitted uncoated
glass fiber mesh fabric with an aqueous coating composition
comprising, with respect to total solids content, (i) from 60 wt %
to 99.9 wt % of the poly(vinylidene chloride) (PVDC) or the
copolymer thereof, and (ii) from 0.1 wt % to 40 wt % of at least a
second polymer selected from the group consisting of a
melamine-formaldehyde resin, a phenol-formaldehyde resin, a urea
formaldehyde resin and a combination thereof; and (b) drying the
impregnated glass fiber mesh fabric by heating at a temperature
between about 100.degree. C. and 280.degree. C. for a period of
time between about 5 seconds to 5 minutes.
9. The method according to claim 8, wherein the poly(vinylidene
chloride) or the copolymer thereof is an aqueous latex composition
having a solids content between 30 and 70 wt %.
10. The method according to claim 8, wherein the
melamine-formaldehyde resin, the phenol-formaldehyde resin or the
urea-formaldehyde resin is added as a non-cured aqueous solution of
an oligomeric resin.
11. The method according to claim 8, wherein the uncoated glass
fiber mesh fabric has a weight of 30 to 500 g/m.sup.2.
Description
[0001] The present invention is drawn to a glass fiber mesh fabric
for use as reinforcement in External Thermal Insulation Complex
Systems. The glass fiber mesh fabric is coated with an organic
polymer coating based on PVDC.
[0002] Glass fiber mesh fabrics are currently used in External
Thermal Insulation Complex Systems (ETICS) to reinforce the render
coating and facilitate application thereof to the underlying
thermal insulation product (foam, glass wool, etc.). Such glass
fiber mesh fabrics are generally coated with rubber coatings,
typically SBR rubber, to provide the fabric with mechanical
strength and to protect the glass fibers against the alkalinity of
the render composition.
[0003] Most of the member countries of the European Union have
adopted the harmonized Euroclass system of reaction-to-fire
performance of building products. The background of the
harmonization process lies on the Commission Decision 94/611/EC
implementing Article 20 of Directive 89/106/EEC on construction
products in the field of fire safety. The Euroclass decision
includes a classification system for building products based on
their reaction-to-fire performance. It additionally defines the
test methods according to which construction products shall be
categorized. To be classified in class A2 (Products of natural
stone, concrete, bricks, ceramic, glass, steel and other metallic
products containing small amounts of organic compounds) of the
Euroclass fire rating system a glass fiber mesh fabric must have a
gross heat of combustion (PCS, French acronym for Pouvoir
Calorifique Superieur), measured according to EN ISO 1716:2010, of
at most 3 MJ/kg.
[0004] Commonly known SBR-coated glass fiber mesh fabrics with a
loss on ignition (L01) of about 20% have a PCS of about 7-8 MJ/kg
and consequently do not comply with the above-mentioned European
regulations.
[0005] Reducing the LOI of SBR-coated glass fiber meshes to
decrease their PCS is not a satisfactory solution because it
results in very poor mechanical resistance of the end products.
[0006] The idea underlying the present invention was to replace the
prior art SBR-based coatings by coatings having lower PCS
values.
[0007] PVDC was one of the most promising candidate for such a
replacement. PVDC and copolymers thereof are a group of
thermoplastic polymers commonly used in the packing industries.
They have excellent gas and water tightness, very good mechanical
performances, satisfactory fire resistance and low combustion heat.
Replacing SBR with equivalent amounts of PVDC however leads to
end-products having satisfactory PCS values but which are too stiff
to be rolled.
[0008] Decreasing the LOI of PVDC-coated glass fiber meshes to
reduce stiffness and cost was also unsatisfactory because the
mechanical properties of the resulting fabrics were low.
[0009] After extensive research the Applicant found that it was
possible to improve the mechanical performances of PVDC-coated
glass fiber mesh fabrics by mixing the PVDC latex with low amounts
of heat-curable formaldehyde-based resins.
[0010] Adding formaldehyde-based resins to the PVDC binder
desirably increases the mechanical strength of the resulting
coating thereby allowing reduction of the overall LOI and in
particular reduction of the amount of PVDC required, which is very
interesting from an economical point of view because PVDC is a
rather expensive polymer.
[0011] The present invention is therefore drawn, in a first aspect,
to a glass fiber mesh fabric coated with an organic polymer
coating, said polymer coating comprising [0012] (i) from 60 wt % to
99.9 wt % of poly(vinylidene chloride) (PVDC) or a copolymer
thereof; [0013] (ii) from 0.1 wt % to 40 wt % of a
formaldehyde-based resin selected from melamine-formaldehyde
resins, phenol-formaldehyde resins, urea-formaldehyde resins or a
combination thereof.
[0014] The above percentages should be understood to be based on
the total amount of organic polymer coating. The sum of these
percentages does not necessarily amount to 100% because, as will be
explained hereafter, the organic polymer coating may further
comprise a plastifying polymer and other optional adjuvants
commonly used in the field of polymer coatings for construction
products.
[0015] The organic polymer coating is preferably free of
substantial amounts of a mineral flame retardant. The uncoated
glass fiber mesh fabric of the present invention may be any open
glass fiber fabric currently used for the production of SBR-coated
glass fiber mesh fabrics.
[0016] It may be a woven or knitted fabric. Its specific weight is
preferably comprised between 30 and 500 g/m.sup.2, more preferably
between 50 and 300 g/m.sup.2, and most preferably between 100 and
150 g/m.sup.2.
[0017] The size of the mesh openings is preferably comprised
between 1 mm.sup.2 and 15 cm.sup.2.
[0018] The warp and weft tensile strength of the mesh fabric
measured on stripes (5 cm.times.30 cm) is comprised between 400 N
and 10 000 N.
[0019] The organic polymer coating may be applied to the uncoated
glass fabric without any pretreatment. The total amount of organic
polymer coating may be expressed as the loss-on-ignition (LOI),
measured according to EN ISO 1887 of the final polymer-coated
fabric. The organic polymer coating generally comprises between 6
wt % and 20 wt %, preferably between 7 wt % and 15 wt %, and more
preferably between 8 and 12 wt % of the final coated glass fiber
mesh.
[0020] Polymers of vinylidene chloride are the main component of
the organic polymer coating. This term includes homopolymers of
vinylidene chloride (PVDC) and copolymers of vinylidene chloride
and of at least another comonomer (PVDC-based copolymers).
PVDC-based copolymers are preferred. Comonomers are preferably
selected from the group consisting of methyl acrylate, ethyl
acrylate, butyl acrylate, methyl methacrylate, acrylonitrile,
methacrylonitrile, unsaturated carboxylic acids, vinyl chloride.
PVDC-based copolymers generally comprise from 75 to 98 wt %,
preferably 80 to 95 wt % of vinylidene chloride monomer units and
from 2 to 25 wt %, preferably from 5 to 20 wt % of comonomer
units.
[0021] As explained above the organic polymer coating must contain,
in addition to the PVDC or PVDC-based copolymer, a thermoset
formaldehyde-based resin, preferably selected from
melamine-formaldehyde resin, phenol-formaldehyde resin,
urea-formaldehyde resin and combinations thereof. This resin is
added to the coating composition in the form of a non-cured aqueous
solution of an oligomeric resin prepared by prepolymerisation of
formaldehyde and phenol, melamine or urea. It is completely
polymerized and cured in situ by heating.
[0022] The organic polymer coating preferably comprises from 0.1 to
10 wt %, more preferably from 0.5 to 8 wt %, and most preferably
from 1 to 4 wt % of melamine-formaldehyde resin,
phenol-formaldehyde resin, urea-formaldehyde resin or a combination
thereof.
[0023] The Applicant has observed that replacing styrene-butadiene
rubber by a PVDC based polymer coating, resulted in a stiffer final
product. To reduce the stiffness of the organic polymer coating and
of the final coated mesh fabric, the Applicant added a plastifying
polymer to the coating composition. This plastifying polymer may be
any organic thermoplastic polymer that is compatible or miscible
with the PVDC or PVDC-based copolymer and has a glass transition
temperature (T.sub.g) lower than 40.degree. C., preferably a
polymer having a T.sub.g comprised between -60.degree. C. and
+20.degree. C.
[0024] Preferred plastifying polymers are selected from the group
consisting of polyacrylates and polymethacrylates,
styrene-butadiene copolymers, styrene-acrylate copolymers,
polyvinyl acetate) and poly(ethylene vinylacetate) copolymers.
[0025] These plastifying polymers are added to the coating
composition as a powder or aqueous polymer dispersion.
[0026] The organic polymer coating of the glass fiber mesh fabric
preferably contains from 0.1 to 40 wt %, more preferably from 5 to
25 wt % and most preferably from 10 to 20 wt % of said plastifying
polymer having a T.sub.g lower than 40.degree. C.
[0027] The present invention also provides a method for producing a
coated glass fiber mesh fabric according to the present invention.
This method comprises [0028] (a) impregnating a woven or knitted
uncoated glass fiber mesh fabric with an aqueous coating
composition containing, with respect to its total solids content,
[0029] (i) from 60 wt % to 99.9 wt % of poly(vinylidene chloride)
(PVDC) or a copolymer thereof; and [0030] (ii) from 0.1 wt % to 40
wt % of at least a second polymer selected from the group
consisting of melamine-formaldehyde resins, phenol-formaldehyde
resins, urea formaldehyde resins or a combination thereof, [0031]
(b) drying the impregnated glass fiber mesh fabric by heating at a
temperature comprised between about 100.degree. C. and 280.degree.
C. for a period of time comprised between about 30 seconds to 20
minutes.
[0032] Impregnation is preferably carried out by immersing the mesh
fabric to be coated in an aqueous coating bath comprising the
components of the organic coating and then pressing the impregnated
fabric between to press rolls to eliminate excess coating
composition. Impregnation could also be done for example by roll
coating or screen coating.
[0033] The PVDC or PVDC-based copolymer is preferably used as an
aqueous latex composition having total solids content comprised
between 30 and 70 wt %, preferably between 40 and 60 wt %.
[0034] The other polymer components, i.e. formaldehyde-based resins
and plastifying polymer are preferably added in aqueous forms
(solutions or aqueous dispersions).
[0035] The coating bath may further comprise any useful adjuvant
currently used in the field of polymer coatings such as thickeners,
buffers, dyes, organic or mineral pigments, UV-absorbers,
brighteners, rheology modifiers, alkali such as ammonia, fillers
such as PVC or carbonates.
[0036] The resulting coated glass fiber mesh fabrics obtained by
the above-described method have a gross heat of combustion (PCS) of
less than 3.5 MJ/kg, preferably less than 3.0 MJ/kg (according to
EN ISO 1716:2010).
EXAMPLES
[0037] The fiber mesh fabric for all examples was a standard glass
fiber mesh fabric (Saint-Gobain Adfors) having a specific weight of
130 g/m.sup.2.
[0038] This fabric was impregnated by immersion in an aqueous
coating bath and then pressed between two rolls before being
cured.
[0039] The coating baths had the following composition (% of
solids) [0040] A: 96.6% of an aqueous dispersion of PVDC (Diofan
A063, SolVin)
[0041] 3% of a melamine-formaldehyde resin
[0042] 0.1% of aqueous ammonia [0043] B: 76.9% of an aqueous
dispersion of PVDC (Diofan A063, SolVin) [0044] 3% of a
melamine-formaldehyde resin
[0045] 20% of an acrylic binder (Printofix Binder CFN) with Tg of
20.degree..
[0046] 0.1% of aqueous ammonia
[0047] The glass fiber mesh fabric coated with 7% (LOI) of
composition A had a PCS of 1.4 MJ/kg.
[0048] The glass fiber mesh fabric coated with 7% (LOI) of
composition B had a PCS of 2.9 MJ/kg.
[0049] The below table shows four comparative coating compositions
resulting either in products having too high PCS or in products
having poor mechanical strength:
TABLE-US-00001 Acrylic PVDC Melamine- Binder Comparative (Diofan
formaldehyde (Printofix aqueous composition A063) resin Binder CFN)
ammonia LOI C 100 -- -- 0.1% 20% D 50% 49.8 -- 0.2% 10% E 50% 0%
50% 0.1% 10% F 60% 0% 40% 0.1% 10%
[0050] The glass fiber mesh fabric coated with 20% (LOI) of
composition C had a PCS of 2.4 MJ/kg but inacceptable rigidity,
brakes during bending, and has poor crosspoint stability
[0051] The glass fiber mesh fabric coated with 10% (LOI) of
composition D had a PCS of 3.5 MJ/kg
[0052] The glass fiber mesh fabric coated with 10% (LOI) of
composition E had a PCS of 6 MJ/kg
[0053] The glass fiber mesh fabric coated with 10% (LOI) of
composition F had a PCS of 2.8 MJ/kg but a poor crosspoint
stability
* * * * *