U.S. patent application number 14/704299 was filed with the patent office on 2021-12-02 for vapor permeable, water resistive, air barrier polyester membrane having a polyacrylic coating with porous pressure sensitive adhesive added to the rear surface of the membrane.
This patent application is currently assigned to VAPROSHIELD, LLC. The applicant listed for this patent is VAPROSHIELD, LLC. Invention is credited to Daniel Bess, Robert Piecinski, Leland D. Snyder.
Application Number | 20210372120 14/704299 |
Document ID | / |
Family ID | 1000005968630 |
Filed Date | 2021-12-02 |
United States Patent
Application |
20210372120 |
Kind Code |
A9 |
Bess; Daniel ; et
al. |
December 2, 2021 |
VAPOR PERMEABLE, WATER RESISTIVE, AIR BARRIER POLYESTER MEMBRANE
HAVING A POLYACRYLIC COATING WITH POROUS PRESSURE SENSITIVE
ADHESIVE ADDED TO THE REAR SURFACE OF THE MEMBRANE
Abstract
An ultra violet stable polyester membrane with a polyacrylic
coating on one side and a coated pressure sensitive adhesive
coating on its other side capable of allowing water vapor to pass
through it. The pressure sensitive adhesive is formed of a
copolymer comprising a backbone of n-butyl acrylate, 2-ethylhexyl
acrylate, and vinyl acetate which is mixed with at least one
surfactant and emulsified to produce air bubbles which form pores
when the copolymer is set with about 80% to about 90% of the pore
sizes ranging from about 200 microns to about 300 microns and being
uniformly distributed to form a flow path through the pressure
sensitive adhesive.
Inventors: |
Bess; Daniel; (Geneva,
OH) ; Piecinski; Robert; (Montville, OH) ;
Snyder; Leland D.; (Gig Harbor, WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VAPROSHIELD, LLC |
Gig Harbor |
WA |
US |
|
|
Assignee: |
VAPROSHIELD, LLC
Gig Harbor
WA
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20160024782 A1 |
January 28, 2016 |
|
|
Family ID: |
1000005968630 |
Appl. No.: |
14/704299 |
Filed: |
May 5, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14121027 |
Jul 22, 2014 |
|
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14704299 |
|
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61958161 |
Jul 22, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 2255/26 20130101;
B32B 2419/06 20130101; B32B 2307/3065 20130101; B32B 2266/0214
20130101; B32B 2255/28 20130101; B32B 2405/00 20130101; C08K 5/0066
20130101; B32B 2307/724 20130101; E04B 1/625 20130101; B32B 27/36
20130101; B32B 2307/71 20130101; B32B 7/06 20130101; B32B 2255/10
20130101; C09J 7/381 20180101; B32B 2266/0242 20130101; B32B
2307/7265 20130101 |
International
Class: |
E04B 1/62 20060101
E04B001/62; B32B 7/06 20060101 B32B007/06; B32B 27/36 20060101
B32B027/36; C09J 7/02 20060101 C09J007/02; C08K 3/00 20060101
C08K003/00; C08K 5/00 20060101 C08K005/00 |
Claims
1. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane comprising a permeable polyester
plastic sheet coated with a polyacrylic coating and bonded
together, a coating of permeable pressure sensitive adhesive is
applied and set on an outer surface of said polyester plastic
sheet, said adhesive comprising a copolymer with a backbone of
n-butyl acrylate, 2-ethylhexyl acrylate, and vinyl acetate which is
mixed with at least one surfactant and emulsified to produce air
bubbles which form pores within said copolymer adhesive when the
copolymer is cured having a permeability of at least 40 Perms, said
pores being uniformly distributed to form a water vapor flow path
through the adhesive, and a release liner mounted over said
pressure sensitive adhesive.
2. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein at least
a majority of said adhesive pores having a pore size ranging from
about 200 microns to about 300 microns.
3. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
pressure sensitive porous adhesive has a peel value using dynamic
peel data from stainless steel of about 65 to about 15.
4. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein the
pressure sensitive porous adhesive has a vapor permeability ranging
from 40 to 70 Perms.
5. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
surfactant has long chain alcohols.
6. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
pressure sensitive adhesive has a density ranging between about
0.65 to about 0.75 after aeration.
7. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
adhesive has a pore density which ranges from about 4000 per
in.sup.2 to about 4600 per in.sup.2.
8. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
adhesive has a pore density is about 4400 per in.sup.2.
9. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 2 wherein about 80%
to about 90% of said formed pores have a pore size ranging from
about 200 microns to about 300 microns.
10. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 1 wherein said
adhesive contains a flame retardant material.
11. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 10 wherein said
flame retardant material is Antimony Oxide.
12. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 10 wherein said
flame retardant material is taken from a group consisting of
halogenated fire suppressants, hydrated inorganic compounds such as
aluminum trihydrate, magnesium hydroxide, calcium borate and zinc
borate, intumescent phosphate, ammonium polyphosphate, organic and
inorganic phosphate compounds such as ammonium sulfate, sulfamate
compounds and free radical scavenger materials such as antimony
trioxide.
13. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane as claimed in claim 10 wherein said
flame retardant material is present in said adhesive in a range of
about 0.5% by weight to about 3% by weight.
14. An ultra violet stable vapor permeable, air barrier building
membrane as claimed in claim 1 wherein said adhesive contains a
flame retardant material of about 2% by weight to about 3% by
weight.
15. An ultra violet stable vapor permeable membrane comprising a
polyester sheet and polyacrylic coating secured together, a coating
of permeable pressure sensitive foamed adhesive coated over an
outer back surface of said membrane, said pressure sensitive foamed
adhesive comprising a copolymer comprising a backbone of n-butyl
acrylate, 2-ethylhexyl acrylate, and vinyl acetate mixed with at
least one surfactant and emulsified to produce bubbles in the
adhesive which form pores when the copolymer is cured, said cured
copolymer having about 80% to about 90% of the pore sizes ranging
from about 200 microns to about 300 microns and a pore density in
the cured pressure sensitive adhesive ranging from about 4000 per
inch.sup.2 to about 4600 per inch.sup.2, said pores being uniformly
distributed throughout said pressure sensitive adhesive to form a
water vapor flow path through said polyester sheet and coating and
the pressure sensitive adhesive.
16. An ultra violet stable vapor permeable building membrane as
claimed in claim 15 wherein said pores are generally round and oval
in shape.
17. An ultra violet stable vapor permeable building membrane as
claimed in claim 15 wherein said pressure sensitive adhesive
contains a flame retardant material.
18. An ultra violet stable vapor permeable building membrane as
claimed in claim 15 wherein a release liner is placed on said
pressure sensitive adhesive material.
19. An ultra violet stable vapor permeable building membrane as
claimed in claim 15 wherein said foamed adhesive has a density
applied aeration ranging between about 0.65 and about 0.075.
20. An ultra violet stable vapor permeable, air barrier and water
resistive building membrane comprising a permeable polyester
plastic sheet coated with a polyacrylic coating and bonded together
to form a polyacrylic front surface and a back surface, a coating
of permeable pressure sensitive adhesive coated to said back
surface of said sheet and cured and a release sheet mounted to said
pressure sensitive adhesive coating, said adhesive comprising a
copolymer which is mixed with at least one surfactant and
emulsified to produce air bubbles which form pores within said
copolymer when the copolymer is cured, with at least a majority of
said pores having a pore size ranging from about 200 microns to
about 300 microns, said pores being uniformly distributed to form a
water vapor flow path through the adhesive, said coated membrane
with a pressure sensitive porous adhesive having a vapor
permeability ranging from about 40 to about 70 Perms.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part patent application claiming
priority and the benefits of U.S. patent application Ser. No.
14/121,027, filed Jul. 22, 2014, claiming priority from U.S.
Provisional Patent Application No. 61/958,161, filed Jul. 22,
2013.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates generally to a water
resistive, air barrier water vapor permeable building sheet or
membrane which is fastened to the building by pressure sensitive
adhesive which is coated on a surface of the building sheet.
BACKGROUND OF THE INVENTION
[0003] Architects and engineers agree that buildings must be able
to breathe; however most commonly used building underlayments and
membranes trap condensation and moisture in wall cavities which can
lead to poor indoor air quality, energy deficiencies and costly
building damage. The North American building industry spends around
$9 billion dollars each year repairing and litigating building
damages from water and moisture. New materials used in building
construction over the last 20 years are energy efficient, but
ventilation poor, resulting in toxic mold claims of over $3 billion
dollars. Air leakage from such membranes can result in increased
energy use of up to 30-40% in heating climates and 10-15% in
cooling climates.
[0004] Proper building envelope design promotes continual drying by
allowing vapor to escape. Moisture can penetrate a building
envelope through materials and rain/snow exposure during
construction. General occupancy also adds to the moisture levels.
Trapped moisture can cause wood rot, swelling and distortion of
lumber, corrosion of metal and reduction of insulation thermal
value. Any or all of these issues result in a high risk of mold,
mildew, building deterioration, poor indoor air quality and health
and safety risks to the occupant. In some states, new air tightness
and energy saving requirements increase the possibility of trapped
moisture, when low or non-permeable air barriers are utilized.
[0005] Current building construction uses barrier sheets or
membranes to form an envelope around the construction to allow the
transport of moisture into and out of a building and to control the
movement of air through a wall or roof covered by the barrier
sheet. Common commercial barrier sheets or membranes are sold under
the Henry Company and W.R. Grace & Co. brands. These and other
commercial barrier sheets commonly use adhesive which is applied to
the sheet so that the same can be secured to a wall or roof.
Problems which occur in these commercial usages is that the
adhesive used is not pressure sensitive or that the adhesive may
not be porous to allow water vapor transmission.
[0006] It is well known to provide a planar carrier membrane with
an adhesive application which is limited on the surface area or
interrupted by adhesive free places. It is also well known to
perforate the adhesive composition after placement on the planar
carrier membrane with mechanical means or with the aid of air
nozzles so that the entire surface of the planar carrier is
perforated.
[0007] Medical dressings or sheets have used a porous adhesive
coated over a substrate surface to allow air flow to reach the
wound and allow moisture to be transmitted away from the wound.
Examples of such dressings having pores formed in the pressure
sensitive adhesive are described in U.S. Pat. No. 4,163,822 issued
Aug. 7, 1979 and U.S. Pat. No. 5,709,651 issued Jan. 20, 1998. A
porous adhesive for corrugated cardboard is disclosed in U.S.
Patent Application Publication Number 2008/0268224 published Oct.
30, 2008. These sheets perform in the same manner as construction
barrier sheets, albeit in a smaller surface application area with
different substrates. A large surface construction barrier sheet
using a vapor permeable adhesive is described in U.S. Patent
Application Publication Number 2011/0018566 published on Aug. 4,
2011. The corresponding United States equivalent is U.S. patent
application Ser. No. 12/937,823 filed Apr. 15, 2011.
[0008] Many construction barrier sheets currently in use are
formulated to be weather resistant keeping out liquid and resisting
wind pressure. These sheets are secured to building sheathing and
form an "envelope" underneath exterior cladding or roofing. Some
commercial barrier sheets are water vapor permeable but have
limited pressure sensitive adhesive applied to specific areas of
their inner surface. Thus, there exists a need for a highly water
vapor permeable pressure sensitive adhesive which can be applied to
the entire inner surface of the barrier sheet allowing it to be
easily mounted to sheathing or the like. The present membrane has
uniform vapor permeable characteristics with higher permeability
over the surface of the barrier sheet with pores in the adhesive
uniformly distributed to form a vapor flow path through the
adhesive.
SUMMARY OF THE INVENTION
[0009] A breathable polyester membrane sheet having an integral
polyacrylic coating and a coated pressure sensitive adhesive strip
or covering coated on its back or inner surface capable of allowing
increased amounts of moisture vapor to pass through it when the
adhesive release liner is removed and the sheet is mounted to a
building surface. The pressure sensitive adhesive applied to the
polyester membrane is formed of a copolymer comprising a backbone
of n-butyl acrylate, 2-ethylhexyl acrylate, and vinyl acetate which
is mixed with a surfactant and emulsified in a foam mixer to
produce a precisely homogenized mix of adhesive and air bubbles
which form pores when the copolymer is set on the membrane. About
80% to about 90% of the pore sizes in the foamed adhesive range
from about 200 microns to about 300 microns and the cured pressure
sensitive adhesive has a pore density ranging from about 4200 per
inch.sup.2 to about 4600 per inch, with the pores being uniformly
distributed and forming a flow path through the adhesive.
[0010] It is an object of the present invention to provide an ultra
violet (UV) stable polyester membrane with a pressure sensitive
adhesive which is porous with the pores being uniformly distributed
and interconnected allowing vapor transmission through the adhesive
and membrane.
[0011] It is another object of the invention to provide an ultra
violet (UV) stable polyester membrane with a pressure sensitive
adhesive covering the entire inner surface of the membrane which
allows water vapor to be circulated through the adhesive.
[0012] It is yet another object of the invention to provide an
ultra violet (UV) stable polyester pressure sensitive porous
adhesive which has fire resistant capabilities.
[0013] These and other objects, advantages, and novel features of
the present invention will become apparent when considered with the
teachings contained in the detailed disclosure along with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of a roll of the inventive
construction membrane;
[0015] FIG. 2 is an enlarged partial broken apart cross sectional
view of the construction membrane shown in FIG. 1 applied in a
building construction environment;
[0016] FIG. 3 is a side elevation view of a building construction
using the present invention with components removed;
[0017] FIG. 4 is a scanning electron microscopy photograph of the
porous adhesive used with the construction membrane at 50.times.
magnification; and
[0018] FIG. 5 is a scanning electron microscopy photograph of the
porous adhesive used with the construction membrane at 200.times.
magnification.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The preferred embodiment and best mode of the invention is
shown in FIGS. 1-5.
[0020] A building construction membrane 10 in the form of a blank
UV stable highly vapor permeable water resistive barrier, air
barrier for open joint rain screen cladding system. UV stable means
that it is applicable in all climates and sustains 180 days
exposure to UV and climate prior to cladding installation. The
inventive sheet 12 is constructed of a permeable polyester sheet
with a polyacrylic coating 13 on its front face and has a layer of
porous pressure sensitive adhesive 14 coated and set over a back
portion of the sheet surface in the form of a strip or over the
entire surface of the sheet. The composite sheet installs as a
single layer black membrane and is particularly useful in
connection with open join rain screen cladding. It emits zero VOC's
eliminating exposure to harmful and volatile chemicals. The surface
of the adhesive is covered by a removable film cover or liner 15.
When the release film liner 15 is removed, the back surface of
membrane 12 with pressure sensitive adhesive 14 is mounted to a
wall board or exterior sheathing or rigid insulation 16 which is
secured to studs 17. As shown in FIG. 2, the outer face polyacrylic
coating 13 is pressed against battens 18 which are secured to an
open joint cladding 22. Air and vapor flow is shown by Arrows A and
B, respectively.
[0021] The membrane 10 is produced as a roll of sheet material 20,
preferably 165 feet in length and with a width of 58-60 inches,
preferably 59 inches. The membrane 10 is ultra violet (UV) stable
water resistant and has a water vapor transmission greater than 40
Perms, preferably ranging from about 40 to about 70 Perms and acts
as an air barrier. The produced membrane is inert and can be
recycled for reuse.
[0022] As shown in FIG. 3, an exterior sheeting or wall board 16 is
mechanically fastened to studs 17 and the sheet 12 is adhesively
secured to sheet 16. The sheet 12 may also be secured by the
adhesive to rigid insulation or other wall substrates as gypsum
sheathing. The open joint cladding 22 is fastened to the battens 18
by mechanical means.
[0023] The pressure sensitive porous adhesive 14 is coated and
cured on the back of the polyester/polyacrylic liner sheet 12 to
fix the pores in place. The composite structure of the present
invention has a high vapor permeability (40 to 50 Perms) and the
adhesive breathes allowing vapor to escape while being water
resistant.
[0024] A Perm is a unit of water vapor transmission defined as 1
grain of water vapor per square foot per hour per inch of mercury
pressure difference (1 inch mercury=0.49 psi). The metric unit of
measure is ng/m2 s Pa. 1 perm=55 ng/m2 s Pa. Permeability is the
time rate of water vapor transmission through unit area of a
material of unit thickness induced by unit vapor pressure
difference between two specific surfaces, under specified
temperature and humidity conditions. Membranes with a higher Perm
value greater than 20 reduce the risk of condensation and promote
escape of moisture through the building envelope. Additionally,
membranes with a high Perm value can help building materials
dry-out during the construction phase.
[0025] The copolymer portion of the pressure sensitive adhesive
(PSA) has a backbone consisting of n-butyl acrylate, 2-ethylhexyl
acrylate, and vinyl acetate. The structure of the backbone is shown
in Table I below as follows:
TABLE-US-00001 TABLE I (Structure of PSA Polymer Backbone)
##STR00001##
[0026] The adhesive fully bonds to almost any substrate for air
tightness and ease of installation and requires no primer.
[0027] The pressure sensitive adhesive (PSA) is an acrylic solution
and bonds to the sheet 12. The polymeric portion of the PSA makes
up at least 95% of the adhesive formulation and has a copolymer
backbone of n-butyl acrylate (about 60% by weight), 2-ethylhexyl
acrylate (about 32% by weight) and vinyl acetate (about 7% by
weight) forming a copolymer solvent blend capable of accepting
water. Proper foaming of the adhesive is critical to good micropore
formation. The aeration process includes high sheer mixing to
entrain air in the mixed liquid solution. Once the proper foam
level is produced, the adhesive needs to be coated on the membrane
sheet and the micropores formed.
[0028] The coating method used with the present invention was a
blade coater. This is a non-contact coating method and it does not
crush or destroy the foam during coating. It should be noted that
other coating methods such as Meyer rod, comma coating and pattern
bar coating were attempted but found to be detrimental to suitable
micropore formation. After coating, the adhesive must be heated to
lock-in the micropore formation. The adhesive in the present
invention was reformulated by adding surfactants and water to the
copolymer to control bubble size, bubble density, viscosity, and
stability of the copolymer. The peel value of the adhesive is
reduced by the introduction of voids (air bubbles) and the addition
of surfactant such as long chain alcohols create a stable inverse
emulsion. The peel value of the presently formulated adhesive
during testing using dynamic peel data from stainless steel (Peel
Adhesion ASTM D-3330) was about 25 oz. in at 1 minute; 27.5 oz. in
at 10 minutes and 36.5 oz. in at 24 hours.
[0029] Microscopy of the modified adhesive surface was performed
revealing a porous structure of the inventive adhesive having a
bubble density (number of pores) ranging from about 4000 pores in
1.0 in.sup.2 to about 4600 pores in 1.0 in.sup.2, preferably about
4400 pores in 1.0 in.sup.2 with a majority of the pores, preferably
about 80% to about 90% of the bubbles/pores having a size ranging
from about 200 microns to about 300 microns. See FIGS. 4 and 5. The
pores formed are generally round and oval in shape and form a vapor
pathway through the adhesive layer. The majority of the pores 100
formed by the entrained air bubbles appear to be distributed evenly
across the surface penetrating through the adhesive layer when the
polymer mixture is heat treated to set or cure the pores in the
adhesive. The pore distribution is shown in FIG. 5. Preferably, the
density of the foamed adhesive should fall between about 0.65 and
about 0.75 after aeration.
[0030] The reformatted PSA was manufactured as follows:
[0031] The adhesive copolymer as shown in Table I ranged from about
45% by weight to about 50% by weight, preferably about 48% to about
49% by weight. The copolymer was mixed with a first solvent-free,
surfactant-based wetting agent, preferably ranging from about 4% by
weight to about 6% by weight, and most preferably about 5% by
weight to provide emulsification and bubble size; and a second
surfactant such as a foaming agent ranging from about 1.5% by
weight to about 2.0% by weight, and preferably about 1.7% by weight
to provide foam formation. A polymeric based water thickener was
added to the mixture in a range from about 0.2% by weight to about
0.4% by weight, preferably about 0.30% by weight. The composition
was added to water ranging from about 40% by weight to about 50% by
weight, preferably about 43% by weight to about 45% by weight and
mixed in a high speed dispersion mixer at 500 rpm to form uniform
bubbles in the mixture and fed into a coater feeder as previously
described. The foamed adhesive was coated onto a porous polyacrylic
coated polyester liner sheet and heat cured to form an adhesive
laminate with pores in place. The resultant foamed adhesive had
average MVTR (g/m.sup.2 day) of about 500 with a Peel adh @1800
(measured stability) ranging from about 65 to IS, preferably about
40.
[0032] The pressure sensitive porous adhesive construction membrane
is preferably made by adding a coating of adhesive as a strip on
the liner sheet with the composition of the adhesive noted above.
If desired, as a building covering membrane, the entire rear
surface of the sheet can be covered with the porous adhesive.
[0033] In a modified version, a flame retardant material Antimony
Oxide was added to the adhesive mixture at about 2% by weight to
about 3% by weight. Other flame retardant materials suitable for
use with the adhesive may include halogenated fire suppressants,
hydrated inorganic compounds such as aluminum trihydrate, magnesium
hydroxide, calcium borate and zinc borate, intumescent phosphate,
ammonium polyphosphate, organic and inorganic phosphate compounds
such as ammonium sulfate, sulfamate compounds and free radical
scavenger materials such as antimony trioxide.
[0034] The principles, preferred embodiments and modes of operation
of the present invention have been described in the foregoing
specification. However, the invention should not be construed as
limited to the particular embodiments which have been described
above. Instead, the embodiments described here should be regarded
as illustrative rather than restrictive. Variations and changes may
be made by others without departing from the scope of the present
inventions defined by the following claims.
* * * * *