Note: Descriptions are shown in the official language in which they were submitted.
Descr ption
An Adhesive ~ssembly
Background oE the Invention
The present invention is concerned with adhesives in general
and to adhering a plurality of substrates.
It is well known in the art today that significant difficulties
are associated with securing side body moldings to vehicles due to the
method of adhering the moldings to the vehicles. Currently employed is
a polyvinyl chloride molding. The industry has applied a plurality of
hot melt adhesive beads on -the outer periphery of said molding with a
bead of one component moisture curable urethane adhesive in between -the
-two hot melt adhesives. The basic purpose of said technique is to have
an immediate adhesion as the hot melt adhesive cools while a more
permanent bond is effected as the one component urethane adhesive cures.
However, it has been found through experience that the adhesive system
employed is not fully satisfactory. Also, if a pressure sensitive
adhesive is used, the molding comes away from the body of the vehicle
due to degradation of the adhesive and its adhering ability to the
substrate by virtue of a delamination principle or by virtue of tha
plasticizer that may be present; in the paint on the substrate or t.he
plas-ticizer that may be present in the polyvinyl chloride molding itself.
Also, it has been found that the adhesion of the moldings to top coat
paints oE the non aqueous dispersion type is very poor. Additionally,
the transportation industry has been looking for a variety of means for
decreasing the weight of au-tomotive vehicles as well as to save energy
in the fabrication of vehicles. The weight problem can be partially
solved by using chemical adhesives to secure a variety of components used
in the transportation industry, thereby eliminating mechanical attachments
or fasteners that may be employed. Additionally, mechanical supports
that are used to hold windows in place may likewise be supplanted with
the use of an adhesive system. Deck lids and hoods which require mechanical
fastening techniques or costly supplementary aids such as welding can also
be a place for the use of adhesives, thereby;decreasing the weight of
the mechanical components. Deck lids and hoods which require dual
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methods to insure precise fit involve costly welding and
unsatisfactory adhesive bondlng which result in high labor
intensity due to clean up of equipment and parts and the
buffing and polishing of par-ts to eliminate pinch weld
marks. These are other advantages for adhesive useO
The theory of adhesives and ~he use of various adhesives
are generally well known in the art~ For a background on
adhesives, see the Handbook of Adhesive Bonding edited by
Charles V. Eagle, published by McGraw Hill, Inc., in
particular, Chapter 19. See also ~pplied Polymer Science
edited by J. Kenneth Craver and Roy WO Tess~ published by
the American Chemical Society, 1975, pages 473 and follo~ing,
for a recitation of well known adhesivesO
Sum_ary of the Invention
__
It is an object of the present invention to provi.de a
novel adheslve assembly~ It i.s also an object o the p.resent
invention to provide a novel process for secur.ing a plurality
of subs~rates to each other, particu:Larly when the substrates
are dissimilar materials.
The invention i.s concerned with an adhesive assembly
comprising- a3 a first adhesive selected from the group
consisting of epoxide, urethane, polyester, alkyd, polythiol,
silicone, e].astomeric rubber, anaerobic, polysulfide, acrylic,
cyano acrylatet acetate, cellulosic, polyamide and phenolic,
b) a second adhesive which is of a different chemical com-
position than the first adhesive, and wherein the adhesive is
encapsulated or is retained in bubbles of a plàstic film; and
c) positioned between the first and second adhesives, a
barrier means for preventing contamination of tne respective
adhesives or the substrates to which they adhere~ wherein
cb/ r
'
the barrier means is also a carrier means for carrying the
adhesives; and components a, b and c being an in-tegral
assembly.
Basically, Applicant's invention relates to the design
and u-tillzation of -the adhesive assemblv as a one package
albeit integrated unit~
The present invention is also concerned with a method
of adhering together a plurality of subs-tra-tes, especially
-2a-
c~ f.
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--3--
dissimilar substrates, utilizing the assembly described
above comprising the steps of:
l. applying the first adhesive to a first substrate;
2. applying a second adhesive to a second substra-te;
5 and
3. positioning a solid flexible resilient barrier
means between the first and second adhesive thereby pre-
venting contamination between the respective adhesives or
the substra-tes to which they adhere.
lO Brief _ c iption of Drawings
Fig. l is a perspective view of the adhesive asse~bly
of the present invention;
Fig. 2 is an alternative embodiment of the adhesive
assembly of the present invention by employing the assembly
15 of Fi~. l with removable backing;
Fig. 3 is a side perspective view showing the
adhesive assembly of the present invention adhering a side
body molding to a vehicle, such as the vehicle door;
Fig 4 is a diagr~nmatic par-t section, part elcvation
20 view of one embodiment of the adhesive assembly;
Fig. 5 is a diayramma-tic part section, part elevation
view of an alternative adhesive assembly construction of
the present invention.
Fig. 6 is a diagrammatic part section, part elevation
25 view of an alternative embodiment oE the adhesive assembly
construction of the present invention.
Fig. 7 is a diagrammatic part section part elevation
view of an alternative embodiment of the adhesive assembly
construction of the present invention.
Fig. 8 is a diagrammatic part, sectional part of an
alternative embodiment of the adhesive assembly construction
of the present invention.
Fig. 9 is a diagrammatic part, sectional part of an
alternative embodiment of the adhesive assembly construction
35 of the present invention with removable backing.
Fig. 10 is a side perspective view of a side body
molding with the adhesive assembly construction attached
thereto further containing a removable covering.
Fig. ll is a deck lid employing the adhesive assembly
40 of the present invention.
Fig. 12 is a sectional view of Fig. 11 taken along
llne 12-12.
. ~ j~. . .
.,~ , .
--4--
~;g. 13 is a sectional view of the window assembly
in a vehicle employing the adhesive assembly construction
of the present invention.
Description of Preferred Embodiments
The adhesive assembly of the present inven-tion
employs any adhesive that can be secured to the barrier
means. The adhesive assembly of the prcsent invention
will be used to secure a plurality of substrates together.
In order to have satisfactory adhesion, the adhesive can
10 be designed to adhere to the particular substrate that is
contemplated. In this manner, the adhesives tha-t are
employed on both sides of the baxrier means would be
different in their characteristics. By "different" is
meant that the adhesives will be of dissimilar chemical
15 construction or be comprised of dissimilar chemical
components or the adhesives will have dissimilar holding
strengths so that it can be said that the adhesives are
not of substantially the same identical components. By
"holding strength" is meant shear adhesion oE the adhesive
20 in the adhesive assembly.
The barrier means useful in the present invention is
generally one that is impervio~s to the components of the
adhesives. ~he barrier means, likewise, should be
impervious to the migration of the components of a
~5 substrate to which the adhesives are applied. As has been
described, the presently employed side body moldings
contain plasticizers in the polyvinyl chloride side body
molding. During the adhesion of the side body molding to
the door of a vehicle, the plastici~er tends to degrade
30 the adhesive, thereby preventing the adhesive from
operating and functioning properly. The present invention
employs a barrier means which can prevent the components
of the polyvinyl chloride from passing through, or coming
into contact with, the adhesive which is securing the side
35 body molding to the wall of the vehicle.
The barrier means can also be considered a carrier
means for carrying the first and second adhesives. Suit-
able barrier means vary with the adhesives employed but
may be paper, a metallic layer, such as iron, steel,
40 aluminum, titanium, magnesium and alloys thereof, and the
like, synthetic organic plastics, such as polyvinyl
chloride, polyethylene nylon, polypropylene, polyester
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film, such as Mylar (trademark of DuPont), and the like.
It is to be appreciatcd that the barrier means may be of
any construction sufficient to carry the adhesives. Such
a construction may require that the barrier means be
5 flexible, resilient and in some cases non-flexible and
have sufficient strength and have a coefficient of
expansion similar to the substrate to which it will be
attached, such as metal or plastics. ~dditionally, -the
barrier means may be corrugatea along its lon~itudinal
10 length in order to maintain its confi~uration a:Eter long
term usage to prevent shriveling, shrinkincl or curling up
at the end of the construction that it is employed, such
as in a side body molding.
The barrier system must be designed with the
15 particular adhesives that are to be employed. For e~ample,
if an anaerobic adhesive is used, it is known that
expulsion of air is required. In such instance, the
barrier means should be constructed such that the side
that faces the anaerobic adhesive could be manipulated
20 durin~ the application of the adhesive to the substrate
so that the air can be expelled from the area between the
substrate, the barrier means and the anaerobic adhesive.
The substrates to which the adhesives will be
applied vary ~uite broadly. ~hey could be metallic
25 substrates, such as aluminum, zinc, iron, s-teel, titanium,
magnesium and alloys thereof, and the like, wood, glass,
synthetic organic plastics, such as acrylics, acetates,
cellulose, acetal, polycarbonates, polyolefins, such as
polyethylene, polypropylene and the like, phenylene oxide,
30 polyamide, such as nylon and the like, polystyrene, poly-
vinyl alcohol, polyvinyl acetate, polyurethanes, poly-
sulfones, polyesters, such as polyethylene -tetraphthalate,
and linear polyesters, such as Mylar (trademark of DuPont
for a polyester film) and the like, fluorocarbons, such
35 as polytetrafluoroethylene, polyfluoroethylene (FEP),
polychlorotrifluoroethylene, polymonochlorotrifluoro-
ethylene such as KEL-F (trademark of DuPont for fluoro-
carbon products including polymers of chlorotrifluoro-
ethylene), polyvinyl fluoride and the like, amino
40 plastics, such as those based upon urea and/or melamine
and derivatives thereof, and the like, polyethers,
phenoxies, phenolics, especially those aerived from
bisphenol-A reacted with epichlorohydrin and the like,
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diallyl phthalate silicones, epo~ides, ionomers such as Surlyn ttrademark
of DuPont) anq the like, alkyds, polyallomers and laminates thereof, and
the like. In addition, the substrate could be a rubber substrate, a
felt substrate which may be based on cellulosic materials and the like,
and other similar materialsO For a listing of suitable plastics,
reference may be made to 1975-1976 Modern Plastics Encyclopedia for a
recitation of resins, films and -the like. It is to be appreciated that
any of the aforemen-tioned substrates may be painted with the usual
primers and top coats employedt such as syn-thetic organic chemical resins
that are lacquers, enamels, non aqueous dispersions, wa-ter soluble and
water borne paints, powder coa-tings and the like.
The adhesives can be formulated in known means depending upon
the variety and type oE adhesives that are to be employed. A way that
is of signif~cant interest is the microencapsulation technique. See
"Advances In Microencapsulation Techniques", Flinn et al, Battelle
Technical Review, 19670 The encapsulation technique can be prepared by
known coacervation method such as that taught in U.S. 2,800,457 and
2,800,458. In addition, dual walled microcapsules can also be employed
as a technique for conta:ining the adhesive. See U.S. ~,076~7~.
A variety oE means of encapsulating adhesivos are well known
in the art. U.S. Patent 3,825,640 indicates that capsules can be
manufactured in accordance with the techniques of interFacial poly-
merization (U.S. 3,~32,327) or phase separation (U.S. 3,~15,758;
U.S. 2,800,457) or solvent exchange (U.S. 3,516,943) or meltable
dispersion (U.S. 3,161,602) or mechanical methods of film impingement
(U.S. 3,015,128) or spray drying (U.S. 3,016,308). A variety of
classes of adhesives may be encapsulated. Some of the more familiar
materials are epoxides, urethanes, unsaturated polyesters, alkyds and
other resins. Liquid adhesive, such as a polythiol with an encapsulated
curing agent, may be prepared thereby having a one part system such
as that taught in U.S. 3,748,313O This technique is applicable not
just to polythiol adhesives but to virtually any adhesive which requires
the use of a curative, for the cura-tive may be encapsulated and the
capsule broken during the desired curing thereof. Encapsulated
techniques are also taught in Chemical Engineering, December 4, 1967,
at about page 177. The technique of containing an encapsulated curing
catalyst for polysulfides is also taught in U.S. 3,505,254.
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A particularly advantageous -technique would be -to apply a
coating to the encapsulated adhesives so -that they may then be applied
as a normal coatin~ composi-tion somewhat similar to a liquid paint,
thereby allowing the substrate -to have the composition attached thereto,
wherein the substra-te is the barrier means described above. U.S~
3,694,243 has a meltable adhesive clinging in a dust-li]ce fashion
about encapsulated adhesives, thereby permit-ting a variety oE adhesives
to be employed. The wall surrounding the adhesives would be a gelatin
or a gum arabic.
One could encapsulate epoxies, polyesters, silicones,
polysulfides or polyurethanes by the techni~ue taught in U.S. 3,725,501,
wherein multiple adhesives with separa-te curing agents for each were
encapsulated in separate compartments so that there would be one
package for the material.
If one wished to have elastomeric adhesive, U.S. 3,813,259
teaches a resin coated encapsulated elastomeric crumbs which contain
various rubber materials.
A particularly preferred technique is the utilization oE
encapsulated anaerobic adhesives. Means for encapsulating said
anaerobic adhesives are taught in U.S. 3,814,156; 3,826,673; and
3,826,756. A pressure`sensitive anaerobic adheslve composition :Ls
taught in U.S. 3,996,308, wherein the accelerator therefor is
encapsulated.
It has been Eound particularly advantageous to have a means
for releasing anaerobic adhesives after they have been cured as a safety
mechanism. The releasing means is in direct contact with a por-tion of
the barrier means, to which the anaerobic adhesive is attached.
Basically, the releasing means is a collection of microencapsulated
organic solvent, which solvent has the capability of dissolving the
cured anaerobic adhesive. Utiliza-tion of such an encapsulated solvent
allows a release of the anaerobic adhesive because the solvent will
dissolve the anaerobic composition which is generally acrylate in
ma/~ _ 7 _
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--8--
nature. Formation of the encapsulated adhesive can occur
through any of the appropriate techniques Xnown in the art.
See Chemical Engineering, supra. The application of an
encapsulated anaerobic adhesive therefore must be such
5 that the encapsulated releasing means, describecl above, is
not ruptured prior to the curing of the adhesive. This
can be accomplished by having the releasing capsules
located on a particular longitudinal portion of the barrier
means but juxtaposed to -the cured anaerobic adhesive.
Any well known organic splvent useful for dissolving
acrylic materials can be employed, such as aromatic
solvents such as benzene, toluene, xylene and the like,
alkyl ethers, ethylene, propylene, diethylene, dipropyle~e,
triethylene, tri~ropylene glycol and the acetate derivatives
thereof, such as the Cellosolve or Carbitol solvents
~trademarks of Union Carbide).
The adhesives may also be secured to the barrier by
means of plastic bubbles containing the aahesives. Such
techniques are will known in the art. See, for example,
20 U.S. 3,677,974,
A particularly advantageous technique is to employ a
plurality of different adhesives as the Eirst ad]lesive.
Additionally, one could use a plurality of adhe~ives as
the second adhesive. This technique can be fulfilled by
25 encapsulating the different adhesives and securing them on
one side of the barrier means. Alternatively, multiple
types of adhesives could be on both sides of the barrier
means, providing the adhesives are "different" as described
above.
It is to be appreciated that by the encapsulation
technique or by the technique of retaining the adhesive
within plastic bubbles, one could use multi-component
adhesives. This is the technique that may frequently be
employed with polyurethanes or epoxy materials where the
35 cross-linking agent or the curing agent employed is
separate from the primary portion of the adhesive system
which is the binder. Anaerobic adhesives could also be
employed in the present application, especially micro-
encapsulated anaerobic adhesives where the various
- 40 components of the anaerobic system are present in a
number of plastic bubbles ox capsules. For example, the
anaerobic cornposition which is the polymerizable monomer
may be in one plastic bubble with the other plastic
b~bles cont~inin~ -the polymerization inhi.bitor, a
polymerl~ation initiator, a polymerization acceL~rator,
and a pla~ticizer and the like.
Due to the increased desire in having lighter weiyllt
5 transporta-tion vehicles, significant emphàsis is being
placed upon synthetic organic plastics o.r compositions to
replace metallic components, such as steel o:r zinc die
castings, in the vehicle. Because of thls, .~pplicant has
found it desi.rable to employ the adhesive assembly of the
10 present invention. Therefore, listed below are a variety
of adhesives that may be employed wi-th the particu].ar
plastic substrates to which the adhesive is -to be applied.
Applicant directs attention to the Handbook of Adhesive
Bonding, supra A variety of plastic substrates are
15 described below for the adhesive assembly of the present
invention.
If one wanted to adhere a substrate to a second
substra-te which is comprised of an acrylic ma-terial, one
coula employ as the second adhesive a polysulfide, a po:Ly-
20 urethane, an acrylic based adhesive, an epoxy, or for aquick set the use of a polycyano acrylate or other
anaerobic compositions.
If one wanted to adhere one suostrate to a second
substrate co~prised of an acetate, cellulose, an acetal,
25 one could employ as the second adhesive an aceta-te, a
cellulosic composition, a polysulfide, a polycyano
acrylate or rubber based polymer.
If one wished to apply a substrate to a second
substrate comprised of polycarbonate, one could employ as
30 the second adhesive a solvent cementing technique, that
is, use a plastic in a solvent, for example, methylene
chloride, which contains a polycarbonate, such as Lexan
~trademark of GE for a polycarbonate), or one may use a
silane primer together with the appropriate adhesive.
If one wished to apply a substrate to a second
substrate comprised of a polyolefin, such as polyethylene,
polypropylene and the like, one could employ a heat
sealed technique where the second adhesive could be a
polyester, a polyamide, an epoxy, a nitrile phenolic, an
40 epoxy phenolic, a polysulfide epoxy, a polyurethane or
other hot melt adhesives or a polyester (U.~. 3,620,~02).
If one wished to adhere a rirst substrate to a
second substrate comprised of polypropylene, one could
use as the second adhesive an epoxy, a polyamide, a
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--10--
polysulfide epoxy, a nitrile phcnolic, a polyurethane
or a hot melt adhesive.
If one wished to adhere a irst substrate to a
second substrate comprised of phenylene oxide, one could
5 use as tile second adhcsive an epoxy, a ni-trile phenolic,
or a polyurethane.
If one wished to adhere a first substrate to a
second substrate comprised of a polyamide, such as nylon,
one could employ as the second adhesive an epoxy, a
10 nitrile phenolic, a nitrile rubber, neoprene or a urethane
and the like.
If one wished to adhere a first substrate to a
second substrate comprised of polystyrene, one could
employ as a second adhesive a polysulfide, a Versamide
15 (trademark of General Mills Chemical, Inc. for thermo-
plastic and reactive polyamide resins) epoxy, or a poly-
urethane.
If one wished to adhere a first substra-te to a
second substrate comprised of polyvinyl alcohol, polyvinyl
20 fluoride, acetates or polyvinyl chloride, one could use a
second adhesive such as nitrile rubber based adhesive,
neoprene, epoxies, polyurethanes and the like. In addition,
polyvinyl alcohol could be cemented with water and glycerin.
If one wished to adhere a first substrate to a
25 second substrate comprised of a polyurethane, one could
use a second adhesive based upon a polyurethane elastomeric
type, an epoxy, a foam which could be bonded with a poly-
sulfide, an epoxy, a polyurethane, a nitrile-neoprene and
the like.
IE one wished to adhere a first substrate to a
second substrate comprised of a polysulfone, one could
employ a second aahesive such as an epoxy, a polyurethane
and the like.
If one wished to adhere a first substrate to a
35 second substrate comprised of a polyester such as a poly-
ethylene tetraphthalate or a linear polyester such as
Mylar~ one could use a second adhesive such as an epoxy,
a urethane, or other elastomeric type systems.
If one wished to bind a first substrate to a second
40 suostrate comprised of fluorocarbons, such as pol~tetra-
fluoroethylene (PTFE), polyfluoroethylene (FEP), poly-
chlorotrifluoroethylene, polyvinyl fluoride, polymono-
chlorotrifluoroethylene, such as KE~-F~ one can use a
.
variety of second adhesives, although -th~ bon~ing strengths
are not particularly high.
If one wished to bind a first subs-trate to a second
substrate comprised of amino plastics, such as urea or
5 melamine based coinpositions, one could use the second
adhcsive of epoxy or a po]yurothane and the like.
If one wished to bind a first substrate to a second
substrate comprised of a polyether, one could use as a
seaond adhesive an epoxy or polyure-thane.
If one wished to bind a first substrate to a second
substrate comprised of a phenoxide, it should be appreciated
that it is difficult -to adhere to the substrates; however,
by employing a pre-sensitizing technique, one may employ
elastomeric systems or urethane epoxies as appropriate
15 secona adhesives.
If one wished to adhere a first substrate to a second
substrate, where the second substrate is comprised of a
phenolic resin, one may employ second adhesives such as
epoxies, epoxy phenolics, nitrile phenolics, or polyamides
20 and the like.
If one wished to bind a first substrate to a second
substrate comprised of a dial].yl phthalate, one could
employ a second adhosive such as an epoxyl polysulEide,
furanes, polyester styrenes, polyurethane, and the
25 utilization of primers may enhance the adhesion.
If one wished to adhere a first substra-te to a second
substrate comprised of silicone, one could use as a second
adhesive a silicone adhesive plus a primer.
If one wished to adhere a first substrate to a second
30 substrate comprised of an epoxy, epoxide or any epoxy
fiberglass filled material, one could use as a second
aahesive an epoxy, nitrile phenolic, an epoxy polyurethane
or vinyl phenolic.
If one wished to bind a first substrate to a second
35 substrate comprised of polyester and laminates thereof,
one could use as a second adhesive epoxies, phenolics or
polyesters.
I one wished to bind a first substrate to a sccond
substrate comprised of ionomers, such as Surlyn ttrademark
40 of DuPont for ionomer resins), one would employ.as a
second adhesive an epoxy or polyurethane.
If one wished -to bind a first substrate to a second
substrate comprised of an alkyd, one wou~a employ as a
second adhesive an epoxy, nitrile, neoprene os polyurethane.
'~
If one wished to adhere a flrst substrate to a second
substrate comprised of a polyallomer, such as a polyallomer
copolymer of propylene and ethylene, one could employ
second adhesives which are similar to the adhesives fox
5 polyethylene and polypropylene.
It is to be appreciated that the adhesives that have
been described above are well known in the art and can be
formulated from well known techniques. See, for example,
the following:
U.S. 3,639,137 teaches a metal fastener coated wi-th
a pressure-activatable encapsulated sealant system where
the substra~e has a curing agent attached thereto on top
of which is a pressure-rupturable capsule that has a
sealant therein. The sealant that is employed is primarily
15 an adhesive of the liquid polysulfide type con-taining a
corrosion resistant compound therein. The fastening
system that is described is generally of the threaded
bolt or rivet type system.
U.S. 2,907,682 teaches an adhesive type tape
20 containing pressure-rupturable capsules with adhesives
of two dissimilar types. Similarly, is U.S. 2,988,460
which teaches microscopic pressure-fracturable capsules
which is a heat sensitive material, tha-t is, that -the
fractured capsules will not release -the adhesive until
25 heated above 100F. In a similar fashion, see U.S.
2,9~8,461 which teaches similar capsules containing
chlorinated rubber and phthalates and chlorinated diphenyl.
U.S. 2,986,477 is guite similar to the -460 and
-461 patents except that it teaches a tacky adhesive
30 comprised of isobutylene polymer.
U.S. 3,663,269 teaches a wall covering that has a
coating of dry encapsulated adhesive which is a heat-
activatable adhesive of the acetate acrylic type.
U.S. 3,565,247 teaches a pressure-sensitive adhesive
35 tape containing a multiplicity of microscopic closed cells
which is formed by a blowing agent thereby foaming the
adhesive. The technique is useful in a fabrication of
aircraft skins from individual aluminum panels, enabling
the manufacturer to insure that pressure will be maintained
40 in the cabins of the planes traveling at high altitudes.
U.S. 3,578,482 relates to the screen coating of a
profusion of pressure-rupturable capsules whose walls are
elastic and readily distorted during their coating through
~S .~.
-13-
a screen onto a substrate, bu-t which are subsc~uently
hardened while on the substrate itself.
U.S. ~,039,705 teaches an anaerobic pressure-
sensitive adhesive stock, such as sheets and self-wound
5 tapes, from which an adhesive layer includlng an anacrobic
resin system can be completely transferred to one substrate
to be bonded to another and cured upon the exclusion of
oxygen. The patent teaches at Column 3, Line 20 and
ollowing, tha-t if the anaerobic pressure-sensitive
10 adhesive system contains free transition metal ions, then
at least the peroxy initiator may be encapsulated in
microspheres which, upon rupture and upon the exclusion
of oxygen, will initiate cure.
U.S. 2,800,457 in general teaches the preparation of
15 oil-containing microscopic capsules of complex hydrophilic
colloid material and to a method of making them by
coacervation.
U.S. 2,785,083 relates to a method of applying an
adhesive to sheet material wherein the adhesive is a
20 silicate glass solution which is applied -to cellulosic
surface materials. The technique is par-ticularly
advantageous to the application of the invention in the
manufacture of plywood.
U.S. 3,592,722 teaches a slidable adhesive laminate
25 which contains a pressure sensitive adhesive layer, a
layer of vinyl filml a layer of release material covering
the exposed surface of the adhesive layer and a backing
sheet. As pressure is applied, the release dots are
fractured so that the adhesive makes contact wi~h the
30 surface,
U.S. 3,750r728 teaches the use of pressure sensitive
adhesive strips in wood millwork wherein the adhesive is a
hot melt adhesive or a pressure sensitive adhesive.
U.S. 3,808,088 relates to a spray process for the
35 deposition of spots of adhesive latexes containing
carboxylic. The spots are discrete droplets of the
adhesive material which is sprayed onto the substrate.
U.S. 3,813,279 tcaches elastic foam carpet underlay
which is encapsulated within a plastic bubble which is a
thin flexible impervious sheet of polyethylene, also having
a thin l~yer of saran so that hermetically sealed would be
foam rubber in a certain amount of water.
. ~ ......................................................... .
7~
-14-
U.S. 3,908,052 teaches liquid crystal display devices
which are sealed in polyethylene ma-terials.
Turning now to a dcscription of the drawings, Fig. 1
shows the adhesive assembly 20 of the present invention
5 having a first adhesive 22 and a second adhesive 24
separated by the barrier means 26. Because the invention
is concerned with a double-backed adhesive, Fig. 2 shows
that the adhesive assembly can havc removable layers 28
and 30 on both sides o the adhcsive assembly. The
10 removable layer generally is in a peelable type ma-terial,
such as paper, thin plastic film or coating, such as
polyethylene, polypropylene, a nylon, Mylar~and the like.
The invention is concerned with a variety of ways
of retaining the adhesives on the opposite sides of the
15 impervious barrier. FigO 4 shows a liquid adhesive 32,
which i5 the first adhesive, and the second adhesive 34
being on the opposite side of the impervious barrier 26.
The adhesives are encapsulated within Eilm coat 36 and 36'
for the first and second adhesive means respectively.
20 Alternatively, the fil~ coat could be an encapsulation
technique where particulate materials in the area oE .01
microns to 100 microns are encapsulated in a known
technique as described above or in a double-walled
microcapsule as described in U.S. 4,076,774 or in plastic
25 embodiments as described abvve. The key point, however,
is that due to the particular nature of the adhesive a
variety of means for holding the adhesive on opposite
sides of the barrier means may be used. For example,
Fig. 4 shows that the adhesive or any of its consti-tuent
30 componen-ts are in the liquid state as contrasted with
Fig. 5 where the adhesive 38 is in the solid state but
incorporated within the film 36 and 36'.
Fig. 6 is a preferred embodiment that relates to
the adhesive assembly of the present invention wherein an
35 anaerobic adhesive 32 which is in the liquid state is
retained in a microencapsulated form by means of film 36
or by means of the plastic bubbles as described above.
The impervious barrier separates the second adhesive which
is preferably in this embodiment as a spongy adhesive mass.
40 In general, utilizing the adhesive assembly of Fi~. 6, a
curing agent would be applied to the substrate and then
the anaerobic adhesive 32 of Fig. 6 would be pressed
againsk the substrate~ In this process, the bubbles or
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the capsules would be burst, the air would be expelled
between the impervious barrier and the metal subst~ate
and the ana~robic composition would be cured.
The spongy surface 24 of Fig. 6 is on the backside
5 of the impervious barrier. The spongy material could be
a pressure sensitive adhesive, generally within about 1 to
about 10 mils in thic~ness, preferably 3 to 5 mils in
thickness. Suitable sponyy Jnasses would be a neoprcne
sponge adhesive, a polyethylene sponge adhesive, a
10 urethane sponge adhesive and the like.
It should be appreciated that any and all oE the
adhesives described above may employ other components
therein to make them stable to the environment and to
ultraviolet light and may also contain other desirable
15 components, such as dyes, colorants, pigments and the
like. It is well known to add W stabilizers and anti-
oxidants to stabilize the adhesive mass.
The adhesive assembly of Fig. 7 is very similar to
the adhesive assembly of Fig. 6 except that the adhesive 32
20 may be of a solid type and that the pressure sensitive
adhesive mass 24 may contain as a protective covering 30
a roll or sheet of paper as described above.
The adhesive àssem~ly described in Figs. 6 and 7
can be used in those situations requiring a quick bonding
25 of a relatively stiff item such as an au-tomo-tive name
plate to a surface to which it fits poorly. To effect the
close fit required, it is proposed that the double-coated
barrier tape shown in Figs. 6 and 7 with the adhesive on
the name plate side of the barrier be of a thick spongy
30 adhesive nature itself or consist of a foam elastomeric
spongy mass with an adhesive coating, while the o-ther
side of the barrier contains or carries the anaerobic
adhesive applied just before making the bond or applied
in the form of a microencapsulated adhesive as described
35 above. Upon asse~bly by pressing on the name plate
usually by a fixture or a mechanical roller, a close fit
between the anaerobic coated barrier sheet and the adhering
surface is assured with the inequalities taken up by the
spongy mass between the other side of the barrier sheet
and the name plate. The mechanical pressing breaks up
the encapsulation of the adhesive present with the close
it obtained excluding the air and assuring curing of
the anaerobic adhesive.
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~ nother alternative is that shown in Fig. 7 wherein
the anaerobic adllesive could be the first adhesive 32
enclosed within the plastic bubbles or microencapsulated
within particulate substances as described above.
5 Attached to the anaerobic adhesive would be the inert
impervious barrier 26 which in turn is attached to a
spongy foam or other type layer to which is attached the
second adhesive 24. This spongy layer 25 is introduced
at this point in order to facilitate handling character-
10 is-tics of the substrate. This type of adhesive assembly
allows sufficient "give" as the adhesive assembly is
being applied to the desired substrate.
Turning to Fig. 8, there are a variety of adhesive
configurations that could be employed. Fig. 8 shows tha-t
15 on bo-th sides of the impervious barrier 26 is a spongy
layerO The top layer 22 in -this case can be a silicone
or urethane adhesive caulk. Such silicone adhesives may
be obtained from Dow Corning or other suppliers. Attached
to the impervious barrier could be a foam or spongy layer
20 to which is attached the adhesive 24. The foam or spongy
layer can be prepared in a well known manner. In the
configuration shown in Fig. 8, the impervious barrier 26
may act more as a carrier because of the nature of silicon
adhesives. The barrier can also act as an ultraviolet
25 barrier to prevent the degradation of the silicon sealant.
Frequently, the composition such as that shown in Fiq. 8
may be used to adhere glass windows to a metallic
substrate on one side ana a plastic substrate on the other
side. It is to be appreciated -that the adhesives as
30 described above could be used depending upon the plastic
substrate one wishes to adhere a second substrate thereto.
For example, one may wish to have a fiberglass reinforced
polyester substrate adhered to glass. This may be
accomplished by employing an epoxy cement or sealant or
35 adhesive on one side and have the silicone adhesive on
the other side. It should be kept in mind that a spongy
layer such as that shown in Fig. 8 would be desirable in
order to impart flexibility to a glass assembly preventing
building up of high stresses due to differences in
40 coefficient of expansion when the assembly is subjected
to cold temperatures. Fig. 9 shows the adhesive assembly
of Fig. 8 except containing peelable backing 28 and 30,
such as paper.
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It is to bc appreciated that the adhesive assembly
of the présent invention disclosed in Figs. 1 and 2 may
be sold as a unit. Alternativcly~ they may be sold to
manufacturers of side body moldings. In this situation,
5 Figs. 3 and lO show that the side body molding 40 is
comprised of poLyvinyl chloride or other type materials
such as Surlyn~or polyester 42 encased within a metal
extrusion 44 having a ~.ylar~coating (not shown). See
U.S. 3,745,056. The PVC 42 is adhered to first adhesive
10 member 22 to which is attached the impervious barrier 26
and to which is attached the second adhesive layer 24.
Again, a plas-tic or paper roll or covering 30 would be
attached to the second adhesive 24 in order to make the
side body molding handleable. After the paper covering 30
15 is removed from the side body molding of Fig. 10, it is
then applied as best shown in Fig. 3 where the adhesive
assembly 20 is shown in perspective as it is about to be
attached to the automotive door 46. Adhesive 24 could be
any adhesive that preferably binds or adheres to metal
20 which ls the door substrate, while adhesive 22 would
preerably be one that adheres best to a ~VC or other
type plastic of which the side body molding 40 is
comprised.
~ deck lid 50 is shown in Figs, 11 and 12 comprising
25 a top member 52 and a bottom member 54 secured by mcans oE
the adhesive assembly 20 best shown in Fig. 12. It has
been found that the top and bottom members of the deck
lid are comprised of dissimilar materials and, therefore,
it is highly desirable that the first adhesive 22 in
30 adhesive assembly 20 be one that adheres best to the
upper deck lid component 52, while the second adhesive 2g
would be one that preferentially binds with the metallic
portion 54. In a similar fashion, a multi-component hood
could be assembled with desirable adhesives.
Fig. 13 is a window assembly 60 which is comprised
of a roof member 62 to which is attached a top support 64
and a bottom support member 66. The window 68 is fixedly
retained within the upper and lower sections 64 and 66
respectively. The upper member 64 has a synthetic plastic
40 member 70 used to retain the window in position. The
adhesive assembly 20 is inserted between the plastic
member 70 and the glass 68. In the insertion of the glass
in the lower member 66, the adhesive assembly is used as
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follows: ~ strip of adhesive assembly is appl:ied to a glass frame 68
so tha-t it engages the periphery oE the qlass Erame in a U-shaped
capaci-ty. Inserting the glass into the window assembly, -the adhesive
assembly 20 is also placed along the periphery of -the -top portion of
the glass. From the inside of the vehicle the glass is then inserted
into the U-shaped portion 72 of the lower member 68 thereby retaining
the glass in the recep-tacle and the top portion is then snapped into
position using adhesive assembly 20 coming into contact wi-th the
plastic member 70.
It, therefore, can be seen that the adhesive tha-t is used
to secure the plastic could be one type of adhesive, such as the
adhesives described above depending upon the plastic, while the other
side of the adhesive assembly would contain an adhesive that would
preferably adhere to the glass and have high tensile sheer strength,
such as a silicone adhesive, with or without a spongy foam layer as
described above, or other type adhesives. Additionally, the adhe.sive
that may be used to retain the glass could be a butyl rubher tape such
as that is made commercially available by PPG. The tape is soft enough
to easily deform when glass is pressed into place, and it accommocla-tes
~0 the poor fit between g`Lass surface and a sheet metal. For higher
strength, a po:LysulEide rubber adhesive may be employed such as that
sold by Thikol Corpora-tion. It has been found desirable tha-t an amino
silane ~manufactured by Goodrich or ~nion Carbide) wiped onto the glass
surface would assure maximum adhesion to the glass prior to the
application of the polysulfide rubber.
Alternatively, a high streng-th urethane caulk may be used.
The material is a one component caulk which is extruded onto the primer
coated glass and cures by absorption of moisture from the airO A
glass primer is used with the adhesive urethane caulk, which is an
aliphatic urethane containing suitable pigments and antioxidants to
give good resistance to ultraviolet rays from the sunO Other
adhesives such as epoxies could also be used to adhere the glass,
but reasonable softness is needed to prevent locali~ed overloading
and breakage of the glass due to impact or s-tresses induced by
differences in coefficient of expansion between the Eilled epoxy and
the glass and the body steel.
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'l'h-ree classes of adhes:ive asserllblies are c3eneral:Ly
considered desirable:
1. The firs-t adhesive is comprised of an anaerobic
adhesive (preferahly retained in bubhles of a plas-tic film
or encapsula-ted) and the second adhesive is comprised oE a
spongy adhesive mass;
2. The first adhesive is comprised oF an anaerobic
adhesive (preferably retained in bubbles of a plas-tic film
or encapsulated) and the second adhesive is comprised of a
foam or spongy layer wi-th an adhesive layer atop the spongy
layer; and
3. The first aclhesive is comprised oE a silicone
or urethane adhesive and the second adhesive is corrlpr~sed
oE a foam or spongy layer wi-th an adhesive layer atop t:he
spongy layer.
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