Note: Descriptions are shown in the official language in which they were submitted.
METHOD FOR FOLIAGE AND OT_~ER PLANT MATERIAL
PRESERVATION AND TOPICA. COLOR
APPLICATION TO .SAME
Bac]cqround of the Illvention
1.Field o~ the Invent~on
This invention rela-tes to preservat:ion o~
Poliaye or l.;ke materials derived from ~reshly
harves-ted plan-ts, eithe.r under cultivation or from
indigenous wild sources, by pressure injection with a
humectant. Such materials are intended for decorative
utilization, to be ofEered for sale through the Eloral
trades industry.
2. Information Disclosure Statement
The preservation and rendering natural in
appearance of various plant materials for decorative,
scientific, or display purposes of an aesthetic nature
have been previously described in a variety of U.S.
patents. Various parallel but unli]ce claims have been
offered in other U.S. patents. Bridgeman et al U.S.
Patent No. 2,057,413 describes a process for
preserving living plants, cuttings, roots, bulbs and
the like by coating with an aqueous emulsion of
carnauba wax and an oleic acid salt.
In Dux U.S. Patent No. 2,026,~73, ruscus,
lready bleaahed and dyed, is softened by soaking 2-5
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minutes in an emulsion of ylycerin and sulphonated
vegetable oil.
Dux U.S. Patent No. 2,083,191 discloses a method
for bleaching and/or dyeing foliage by submerglny in
ethyl or methyl alcohol at e.levated pressure and
temperature. The alcohol can be used only for 4-6
batches because wa-ter displaced from the oliaye
dilutes the alcohol to below 172 prooE, too low for
proper bleachiny. This is true despite replenishment
of alchohol ahsorbed by the foliage.
l~orupp et al IJ.S. Patent No. 1,484,656 describes
a process for producing decoratlve oliage. Cut
plants are first dried, and then softened in a a~ueous
mixture of ylycerin and formalin. After the plant
surfaces are again dried, paint and/or varnish is
applied to seal the glycerin within the treated plant.
Complete pre-drying is essential to adhesion o the
paint or varnish to the foliage.
In Romero-Sierra et al U.S. Patent No's.
4,278,7~5 and 4,328,256, plant tissues are preserved
with their natural color fixed by immersion in a
complex solution containing (a) water, (b) an alchohol
exchange medium, (c) preservatives, and (d) buffers,
mordants and modifiers.
Sheldon et al U.S. Patent 3,895,140 describes a
process for preserving cut green foliage by extracting
the normal fluidr therefrom and imbioing a polyol,
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e.g. glycerin, in place thereof, at 140-250F. The
preserved foliage may be dyed by soaking in pigment
containing glycerin solutions.
It has been set forth in U.S. Patent No.
4,287,222 to Robinson that fresh foliage material or
other plant materials of a slightly dehydrated nature
can be preserved by the injection under pressure o~
humectants belonging to the polyol class o~ materials,
suah as glycerin, ethylene glycol, and various
polyethylene glycols. Most specifically, its claims
demand that the density of such humectant material
should fall within the speciEic gravity range of 1.10
and 1.16. Commensurate with such preservation
; techniques is the coloring of such materials by the
direct combination of compatible dyes with the
humectant agent, which are likewise forced under
pressure in the plant materials. Subsequently, after
apporopriate duration of treatment with both humectant
and dye, the plant material is withdrawn, rinsed in
cold water, and dried to a natural state. It has been
our experience, in fact, in evaluating the Robinson
claims that no dye, out of fourteen classes of dyes
involving at least one hundred combinations of dye
materials, retained the desired stay-fastness in the
plant foliage. In our tests, the specific dyes cited
in the patent failed to achieve the desired result.
Moreover, with the exception of the basic green-l
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class of dyes, none of the dyes was unlformly absorbed
in-to the material so as to render a natural color. No
dye likewise was found which provided in the end
result a stay-fastness of any signiEicant duration.
Finally, under no circumstances were we able to
demonstrate consistency in preservation which resulted
in the desired natural conEiguration, teix-ture and
structural retention of foliage with any combin~-tion
of glycerol water. At glycerol concentrations
specified in the Robinson patent, and even at
concentrations as low ais those with a specific gravity
of 1.08, extensive swelling and rupture of the plant
tissue cells was observed by frozen section
microscopic analysis. The ylycerol humec-tant
subsequently escaped the foliage structure by
evaporation and biodegradation. The so-called
preserved foliage rapidly curled, dried and
decomposed.
SUMMARY OF THE INVENTION
In developing alternative methods, we have
observed that numerous mitigating factors contribute
to the behavior of natural plant material, including
foliage, under humectant pressure treatment. These
include the freshness and development stage of
foliage, the type of foliage to be utilized and most
critical for uniform large scale preparation of
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preserved materials, the nature o~ the humectant.
Accordingly, a present objective of this invention is
a method for treating freshly harvested plant
materials, specifically foliage materials, which does
not entail any prior process of denaturing such
foliage materials by bleaching, the addition of
chemica.l additives, or any process other than optional
cleaning of the foliage by simple water-surEactant
wash prior to its preservation. Even such washing may
be omitted i~ the foliage is free of any surface
contaminants. The objective is to yield as an end
result a material that has long term shelf life and
long term use for decorative or ornamental purposes,
as well as educational, expositional, and sentimental
purposes. More specifically, an objective is to
produce a treated and coated material which has a
minimum shelf life of six months at 60-90F (16-
32C) and 50 percent relative humidity. More
preferably, a shelf life of at least one year is
desired. Because the prime harvest season is
: relalatively short, foliage is generally treated for
preservation and stored for later color application.
Thus, the treated but unsealed and/or uncolored
material will preferably have a shelf life of at lea~t
;25 four months. However, the scope of the method does
not require that the terminal appearance of the
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foliage is to be absolutely natural and lifelike,
although the process described within will in fact
meet such qualifications. lt is possible by the
present invention to generate foliage having virtually
any color, whether natural or exotic in nature,
dependent only on availability of the requisite
colored coating formula-tion. Thus, foliage of
numerous colors, as well as foliage having a colorless
appearance, can be formulated and prepared to have the
configuration of living foliage. The terminal
objective of the present invention is to in fact
provide a process at a high level of performance
conducive to large scale manufacturing production of
said materials. Whereas the mere preservation of the
foliage material may not involve a specific dexterity
related to artistic considerations, the coloration of
the material by application of surface coatings and
its texturing to natural color does involve the
aesthetic judgment of artistic color texturing.
However, the materials involved in application of such
artistic texturing are formulations of commercially
available materials designed to achieve specific
aesthetic effects.
In summary, this invention is a method for
preserving natural plant materials, including cut
foliage, to enhance their appearance and decorative
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use .
A batch of the plant materials is ~irst immersed
in a starting volume of ethylene glycol having a
specific yravity of 1. 0~ to 1.10 at a pressure oE
about ~ - 30 psig (~bout 0. 21 - 2 .1 kg/cm2 gauge) for
a period o~ four hours to five d~y~ Thi~ range of
specific gravity corra~ponds approximately to 2~-77
percent ethylene glycol. The plant Eluids are
partially exchany~d wi~h ethyl~n~ glycol, producing
treated plant materlals containing ethylene ylycol of
specific gravity 1.025 - ~.10. The lower value of
speci~ic gravity, i.e. 1.025, corresponds to
approximately 19 percent ethylene glvcol.
The treate~d materials are withdrawn from the
pressurized immersion in the spent ethylene glycol and
washed to remove excess ethylene y]ycol from their
surface. The materials are then drled to the touch
for use or further treatment.
The spent ethylene glycol is restored to its
starting volume by adding ethylene glycol having a
concentration no lower than specific gravity 1.03.
PreEerably, virgin ethylene glycol is used. The
restored humectant is reused to treat additional
batches of plant materials according to this process.
The use of fungicides, bactericides, dyes,
buffers, moxdants, and/or modifiers in the exchange
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medium is avoided.
Following treatment with ethylene glycol, the
plant materials may be topica:Lly coated by one of
several methods.
In one method, the maeria;Ls are first dipped in
a hydrophilic polymeric subcoating sealer. The sealed
materials may then be topically tinted, if desired, by
dip-coating or spraying with a blend of pigment in a
water dispersible adhesive or polymeric medium.
Alternatively, the foliage materials may be
sealed and tinte~ in a single step, for example with a
blend o~ hydrophilic polymer and pigment.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Preserva-tion and Permanency Retention of I -
Folia~e Structure
This invention comprises a method which demands
as an essential consideration the utilization o~
ethylene glycol in the specific gravity range from
1.10 to as low as 1.03. No other humectant
composition has been found to be suitable to meet the
same quality of product as that to be obtained from ;~t
ethylene glycol. The best results are obtained in a
specific gravity range of 1~05 - 1.10, but operational
product can be obtained for material of a specific t~
gravity down to as low as 1.03. Optimum results,
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however, are ob-tained for the above specific gravity
ranye of 1.05 to 1.10, as measured at 20C. The
exemplary preservation then involves the bundling of
freshly cut foliage which has not been precoated in
any way by any agent. Most specifically, prohibition
is demanded against the utilization of any other
chemical agents, such as fungicides or interim
preservatives often utilized to coat foliage. Such
materials should all be excluded from material to be
utilized for preservation. It is often advantageous
to remove any surEace contamination of foreign matter,
e.g. dust or dirt adhering to said foliage by a brief
washing with cold wa-ter, with or without detergent~
At the same time, however, certain foliages which have
been desiccated to a considerable degree may likewise
be preserved, as long as their structural integrity
was retained following desiccation. Thus, up to about
three pounds of all such foliage per gallon of
ethylene glycol (0.36 kg per liter ethylene ylycol)
are inserted into a large immersion pressure vessel
and ethylene glycol is subsequently added to the same
vessel. Alternatively, the humectant is placed in the
vessel first.
To the ethylene glycol may be added an
antifoaming agent in order to suppress foaming or gas
entrainment during the pumping of ethylene ~lycol
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preservative~humectant in a continuous operation
process. Antifoam agents having a silicone base are
preferred, although other types may also be
satisfactory. The antifoam agent of choice is a
silicone defoamer marlufactured by Dow-Corning Company
of Midland, Michigan. The specific serial yrade and
product line is Anti-Foam DB-llOOA. For two hundred
gallons (750 liters) o~ ethylene ylycol, approximately
thre.e ounces (85 grams) of the foaming agent is added.
This need not be recharged except after ex-tensive
reuti].ization of the ethylene glycol so as to preserve
foam suppressions. In one embodiment, the immersion
vessel containing ethylene glycol and fresh foliage is
then sealed and external pressure of air or other
insert gas is applied.
While this method is satisfactory for some
materials, most foliage species are more uniformly
treated in a shorter time period by expressly
eliminating gas from the pressure tanX. In the
absence of vigorous agitation, gas bubbles adhere to
foliage surfaces and prevent penetration of humectant
into the foliage.
Therefore, in the preferred embodiment, the
humectants are introduced with a strong flow from the
bottom of the vessel to wash out all traces of gases
clinging to the foliage surfaces and the gases
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entrained in the humectant. ~s the liquid flow is
continued and essentially all gas bubbles are purged
from the pressure vessel, the outflow at the top of
the vessel is closed and hydrostatic pumping of
humectant is continued until the desired internal
pressure is achieved. Other methods of pressuriziny
the vessel may alternatively be used, provided no gas
is introduced into the vessel, and the foliage is
treated in humectant essentially free of gases. We
10 have observed that for many species, elimination of
yas bubbles enables the production of a high quality,
uniformly preserved material in a much shorter time.
For most product lines, good penetration and
preservation with ethylene glycol is thus achieved in
15 treatment periods as short as four hours. More woody
foliage and foliage having a dense structure or
massive texture may require longer periods of pressure
soaking (eight to twelve hours being typical).
In addition, the elimination of entrained gas by
20 this method also reduces the ef~ects of foliaye
maturity and post-harvest age upon the required
treatment time. Thus, a uniform~ relatively brief
treatment period may be used to ~reat a wide variety
of materials without regard to such factors as
25 maturity or post-harvest age.
From a commercial standpoint~ it is advantageous
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to minimize the processing time without sacrificing
quality. We have found that, depending on the
particular plant material and operation temperature,
an immersion pressure of 3 - 30 psig (0.21 - 2.1
kg/cm2 gauge pressure) produces the best results in a
short processing time and at the lowest cost.
The rake of absorption of the humectant and
curing of the foliage is directly proportional -to
freshness of Eoliage, temperature oE ethylene ylycol,
and incrementally related to pressure. The specific
pressure ranye is not critical per se. a minimum,
however, of approximately 3 psig (0.21 kg/cm2 gauge)
to a maximum of approximately 30 psig (2.1 kg/cm2
gauge) produces sakisfactory results. In fact, the
preservation and the humectant absorption of the
foliage may be done entirely without pressure, but
requires considerably longer duration for absorption
of the humectant. The optimum temperature range is
from 70F (21C) to approximately 105nF (41C), and
the best results are achieved with the freshest
foliage. Light leaf foliages are readily preserved
under such treatment for a period of 4-48 hours.
~eavier wooded foliages, such as leather leaf fern,
require a minimum of 48 hours of such pressure
treatment. Heavy wooded foliages, leather leaf fern
being a good example, and other examples such as
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heather or palms of various lcinds, may in fact be
improved in quality of natural characteristic by
subsequently withdrawing from the pressuxe treatment
process and soaking for an additional period of up to
one week at atmospheric pressure in ethylene glycol of
specific gravity 1.05 or higher. Preferably, ethylene
glycol of specific gravity between 1.07 and 1.10 ls
used. During the pressure treatment, and durlng
atmospheric coaking, the bulk materials are preferably
periodically or continuously ayitated in order to
expel any adhering or entrained air-gas bubbles from
the foliage matrix. This may be done, for example, by
tipping, turning, or rolling the immersion tank to
achieve liquid movement through the foliage.
It is most convenient to withdraw the ethylene
glycol in large quantity from the pressure tank by an
efficient surge pump. The antifoam agent will
suppress all foaming during transfer. Likewise,
loading of such tanks is best achieved with a high
volume surge pump. During such pressure treatment
with ethylene glycol, most o the green coloration of
chlorophyll is lost from the foliage structure and the
~oliage assumes an off-gray to a grayish-tan
coloration.
Freshly withdrawn foliage is stacked in piles on
racks from which excess ethylene glycol is drained
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into a catch tank. Su~sequently, the foliage is
washed with cold water to which has been added only a
very small amount of a nonionic deteryent of any
variety, or a blended surfactant such as castile soap,
e.g. Lux'U soap. Once surface adhesion of ethylene
glycol has been removed, the foliaye is shaken free of
excess wetting due to water and hung to air dry to a
state equivalent to that of natural nonwetted foliage.
The required time for ~rying is inversely proportional
to the velocity of air movement within the racked
foliage. The drying time may be reduced by increasiny
air circulation through the hung foliage and/or by a
slight elevation of temperature. Heavily structured
foliage, such as leather leaf fern or various palms,
may on occasion require a second washing due to a
depressurizing blead-out of the humectant ethylene
glycol from the material. Subsequent topical
coloration of the preserved foliage demands that the
bulk of ethylene glycol be cleaned from the foliaye
surface. Therefore, the number of washings required
to bring the foliage to a surface clean condition
varies. Excessive surface ethylene glycol is readily
apparent by appearance and feel. Strictly speaking,
the dried foliage surface is not free of ethylene
glycol. In all cases, a very thin layer of humectant
remains at the foliage surface because oE capillary
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action.
Despite dilution ~lith plant moisture, the
ethylene glycol recovered from the preservation
process may be reutili~ed in effect indefin~tely
without any apparent degracla-tion. The only
requirement is that additional ethylene glycol having
a specific gravi.ty no lower than 1.03 must be added
back to the used ethylene glycol to bring the total
volume baclc to the starting quantities. PrePerably,
virgin ethylene glycol is used. We have observed
reutilization of a crude batch of ethylene glycol by
the incremental readdition of virgin ethylene glycol
for over eighty consecutive preservation runs without
loss in product quality. Thus, purification of the
ethylene glycol, e.g. by distillation is rarely if
ever required. Depending on foliage, anywhere from
five to fifteen percent of the original ethylene
glycol is taken up from a bath-volume ra-tio of three
pounds foliage per gallon (0.36 kg per liter). During
such reuse of the ethylene glycol, its specific
gravit~ rpaidly falls from the initial starting value
of 1.10 to incremental values significantly below l.lo
for example, to 1.07 or 1.0~, or even 1.03.
For some foliage lines it is often advantageous
to allow the material to cure for one wee~ to two
weeks prior to its subsequent utilization. ~lowever,
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light grained foliage such as sprengeri or plumosus
dry quickly and leave very little residual humectant
and may be carried on to the coloration step almost
immediately.
In the event that foliage need not be colored
for its end use, it may be utilized in its preserved
form in a tannish-gray appearance. It slowly changes
over a period of four to five days Erom a tan gray to
an amber brown color. If exposed to sunlight for
varying durations, e.g., 20-100 hours the colvration
bleaches to a pale buckskin tan. It is the intent of
this invention to market such tan colored foliaye
under the color lahel of "Buckskin." Most foliages so
exposed to sunlight achieve the "Buckskin" colora-tion
within a period of four to five days for an eight hour
day of direct sunlight exposure.
The plant material which may be processed by the
above invention is most extensive and includes, but is
not specifically limited to the following. However,
for commercial purposes, the following bear specific
note: sprengeri, plumosus, tree fern, ming, plumosus
stringers, marsh grass and peopper grass are preserved
in two days preservation time. Deer foot moss,
Spanish moss, reindeer moss, and other such mosses are
preserved in one day preservation time. Various
ferns, including leather leaf fern, sword fern,
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~lorida flat fern, and all other such ferns, are
preserved in two to three days, followed by optimal
results obtained from an additlonal week of soakiny in
ethylene glycol at atmospheric pressure. Maynolia and
Palmetto likewise require the same treatmenk as
leather leaf fern. Sparkle berry, aspidistra, Florida
huckleberry, and any other variety of huckleberries;
ivies of all types, including large ivy, grape ivy,
small ivy, and ivie~ relat~sd to the mistletoe
varieties, can be treated in three days without
additional soaking at atmospheric pressure. Florida
ruscus, coon tie fern, West Coast huckleberry, West
Coast Salal, bear grass, tipi fern, champas, cypress,
small Florida bamboo, medium bamboo and large bamboo
require three days preservation time without
additional soaking. All varieties of pines, spruces
and first, including Frasier fir, ~ustrian pine,
Florida shortleaf pine, white pine, black spruce,
Hamilton spruce, two hemlocks, and all other
evergreens, require three days of treatmen-t. The
preceding is but a partial list of plant materials
which have been processed successfully through the
utilization of the present invention. Other foliages
are amenable to the same process as described or with
only minor variations. The treatment time may vary,
depending on the production schedule and plant foliage
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quality.
z. Application of Lifelike Natural Green Coloran_
and Other Colorants
The desirable color and hue may be applied to
the preserved plant material by topical-dip
application oE an acrylic base subcoating, ~ollowed by
a tinting applied under pressure spraying.
Alternatively, a one-step topical coating may be
applied, saving time and expene~e. A wide variety of
colors and hues may be applied without restriction to
the nature of foliage. The critical faator in the two
step process is tha-t an appropriate underlayment is
first applied to the foliage followed by a very light
tinting to bring the foliage to the desired hue. In
the case of green or natural appearance the
formulation is subsequently described. ~or purposes
of example, alternate colorations will likewise be
; described. The practice in general follows in such
fashion: The plant material, such as a single leaf or
multiple bunches of sprigs, having previously been
washed of all surface hemectant, is air dryed,
generally above 70F (21C), to the touch. This
material is dipped into an hydrophilic base coating
which totally masks any underlaying color of the
foliage and adheres to the foliage surface despite the
layer of ethylene glycol. During the preservation
process, the natural chlorophyll green color of the
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~oliaye has been destroyed due to dehydration,
chemical degradation, or photo fading. Once the base
coating has been dip applied and dried, the primary
color tonent is applied under pressure spray. The
critical feature to be achieved is a coating o~ high
integrity, high retentiveness t no tackiness, and
luster or texture comparable to natural foliage. IE
alternate~ shades, colors, or hues are re~uire~, these
may be achieved without intent to duplicate or
simulate natural appearanae.
The following is an exemplary ~ormulatlon for a
natural chartreuse green foliage blend. The ~irst to
be described is the base coating which is applied by
dip to the foliage material. This does not exclude
numerous other possible combinations which may result
in satisfactory product quality. The base coating
achieves its ~ilming and sealing properties from an
acrylic-glue blend underlayment. The acrylic
underlayment utilized within the exemplary process is
manufactured by McWorter Chemical Corporation,
Carpentersville, Illinois, and marketed under the
trade name oE Aquo-~ac~ 607 or 609 series. Likewise,
the exemplary pigments utilizad for the application of
appropriate colorants are marketed by Val-Spar
Manufacturing, Rockville, Illinois, and marketed under
the Tint-EZE~ label. Desired green color combinations
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are obtained ~rom the four component listing of
constituents. These include: Pthalogreen-623, Organic
Yellow-611, Titanium White-600, and Lamp Black-691.
In the suhsequent tinting process the base media can
be any variety of water dispersable adhesive or
polymeric media which binds well to the acrylic
underlayment and like the base coat imparts sealant
properties upon the foliage. In our proce6s optimal
results have been obtained wlth one oE two alternative
materials. These include a formalclehyde based
adhesive manuEactured by H. B. F'uller Company of
Minneapolis, Minnesota, Adheisve X-3801; or
alternatively, an antitranspirant manufactured by
Agro-K Corporation of Minneapolis, Minnesota, mar]ceted
under the label of Envy-Antitranspirant~ The
preparation of stock solutions o~ base colorants and
tinting agent involve the following:
A. Base Coating Colorant Combination - Green.
Four cups (0.95 liter) of the Pthalogreen-
623, two cups (0.47 liter) of Organic
Yellow-611, and one cup (0.24 liter) of
Titanium White-600, are blended with seven
cups (1.656 liter) of water to form a
dispersed paste. To this dispersed paste
is mixed two gallons (7.57 liters) of the
Aquo-Mac~ 607 or 609.
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B. Stock Solution Base Colorant - Yellow.
Five cups (1.18 liters) of Oryanic Yellow-
611 is likewise blended with five cups
(1.18 liters) of water to produce a
dispersant-paste. This is likewise blended
with two gallons (7.57 liters) of Aquo-Mac'~
607 or 609. Usiny the above stock blends,
the mixture designed as the dipping coat is
then formulated as Pc~llows: Seven quarts
(1.656 liters) of the green piyment stock,
_, are mixed with six quarts (1.42 liters)
of the yellow piyment stock, B, and added
to two gallons (7.57 liters) of 50:50
aqueous Adhesive 3081, or two yallon~ (7.57
liters) of 50:50 a~ueous Envy-
Antitranspirant~. After efficient blending
the total mixture is then diluted with
twenty gallons ~75.7 liters) of methyl
alcohol. This then constitutes the base
dip material. In the event that foliage is
being utilized which is very nonuniform in
color due to the preservation process, or
due to bleach out of background colorants
due to the preservation process or sun
exposure, trace amounts of Lamp Black-691
are then blended to obtain depth of tone.
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On most occasions, no Lamp Black need be
added. The amounts wh:ich are added in
exceptional cases constitute quantities in
the vicinity of a tablespoon (15 mL) or
less. If a heavier application of coating
in the base coating dip process i8 desired,
then lesser ~uantities of methanol are
utilized. Likewise, lighter coveracJe may
be obtained by usiny a higher dilution of
methanol.
The pigment toning material which is applied as
a spray blend to base coated foliage is prepared by
utilizing one part oE yellow pigment blend B to four
parts of pure methanol. To diminish the intensity of
15 the yellow and to render it more o~ a chartreuse green
color, small amounts of the green pigment base A are
. subsequently added. ThUs a typical ~ormulation would
; involve one gallon (3.78 liter) o~ pigment B, four
gallons (15.14 liters) methanol, and one-half cup
(0.12 liter) of pigment blend A.
The actual application of colorant to foliage is
a simple direct procsss. The foliage as individual
sprigs or as loosely tied bundles is dipped into the
base coat blend and swished through this media.
Entrained or adhering air bubbles are so purged from
the foliage surPace. Tbe foliage is then shaken to
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drain any excessive film of the colorant base coat
blend and immediate:ly hung to dry in an inverted or
upriyht configuration which allows good passage oE air
provided by natural air movement or enhanced by ~an
circulation. At 70F (21~C) and 50~ relative
humidity, the base coat dries on most foliages to a
state of low-tackiness within five to ten minutes. An
addi.tional one-half hour of curing is recommended
prior to subsequent toning. Toning, however, may be
delayed indefinitely.
In this example, the natural tone blend of
yellow is applied by one of two methods utilizing a
commercial spray painting meachanism, but may be
obtained with any nature of air-assisted, air brush,
film application spray gun. Thus, utilizing the blend
of toner containing pigment B, methanol, and small
amounts of pigment A, a Binks-Vantage~ BB-2 Gun fitted
with a nozzle size of 0.015 inch (0.38 mm) i5 fed
through a paint pot reservoir of 15 - 35 psig (1.05-
2.45 kg/cm2 gauge) within a well ventilated sparkfree
paint booth. Individual bunches of foliage are toned
to aesthetic standards depending upon individual bunch
size and foliage type ov~r two to ten second
durations. Individual operators develop varying
proficiencies of application of toner. The ~inks
series mechanisms involve a fixed paint application
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spray cone and operate at variable air assisted
pressure. Alternatively, utilizing the same toner
blend, an air-over-fluid standard paint gun with pain-t
feed ~rom pressure pot will prove functional. Any
S spray gun possessing variabl~e flow and variable
pattern parameters, and preferably having an external
paint mix mechanism, provides satisfactory results.
Immediately a~ter spraying, the toned ~oliage
bundles are laid on ~lat racks, or they can be
directly hung. Within seconds a~ter application the
toner has dried to insiynificant tackiness so that
individual bundles of ~oliage or individual sprigs o~
foliage do not adhere to each other or disrupt the
finish by contact. However, at 70 (21C) an
additional thirty minutes of drying time on such flat
racks is allowed prior to packaging. Alternatively,
the toned foliage bundles or individual sprigs may be
attached to a mobile conveyor in a heated, 110F
(43C), air drying tunnel and within less than three
minutes the material exits the tunnel, ready for
packaging. Individual bundles are bagged in
polypropylene clear bags according to shipment scale
design and twist-tie sealed.
As described in the above example, the coating
so applied renders the foliage natural and lifelike in
color and inhibits transpiration of entrained
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humectants. Its shelf life under the conditions of
production are significantly improved due to the
application of the base coating and its sealant
components of adhesive or anki-transpirant such as
outlined above. Numerous other possible combinations
of antitranspirants or sealing adhesives are feasible
for this process.
Foliage which is to be rendered bleached of
color due to sun bleaching after preservation in
ethylene glycol is likewise dipped with a sealant.
The preferred sealant blend is a combination involving
the Fuller Adhesive X-3801 or Agro-K Corporation Envy-
Antitranspirant~ blended with twice the volume of
Aquo-Mac~ 607 or 609 Acrylic Media and subsequently
diluted with an equal volume of water. This in turn
i5 then diluted with ten parts by volume of methanol.
The total milky dispersant blend is utilized as a dip
on the buckskin line of foliage and allowed to air dry
in identical fashion ko the pigment application base
coat. No additional colorant need be added. However,
if pure white foliage is to be produced, such a
transparent base coat is subsequently oversprayed with
any variety of Tikanium White-600 tone coatings by
spray application. A typical tone coating by spray
applications would involve a blend of one cup ~0.24
liter) of Titanium White-600 dispersed in one cup
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(0.24 liter) of water which in turn is added to one
gallon (3.78 liter) of Aquo-Mac and one-half gallon
(1.89 liter) of Antitranspirant or Adhesive 3801 and
diluted with ten gallons (37.8 liters) of methanol.
White toning is applied in similar fashion to that
described for the application of the natural
chartréuse green toning color.
The above are simple examples; numerous other
possible color combinations may be applied using
various varieties and classes of pigments. Thus, for
example, foliage may be produced of a red, pink,
yellow, blue, gold, silver, orange, or any other
natural or unnatural blend of colors.
Although the two-step process of sealing and
tinting described thus far works well with all types
of foliage materials, most foliage types may be
effectively sealed and tinted in a single step with a
hydrophilic blend of polymer and pigment. Other
possible components may include extenders,
dispersants, thickeners, solvents, antifoam agents and
pH control agents. This topical coating is most
easily applied as a dip-coat, but it may also be
applied by spraying. The hydrophilic nature of the
blend is most critical to ensure adhesion to the
effectively wet foliage surface having ethylene glycol
adhering to it.
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The following exemplary one-step Formulation A
renders preserved foliage natural in color and general
appearance, and uses a green pigment latex which
provides uniform coverage and a depth of tone which
masks all decolorization effects resulting from the
preservation process. The polymer latex vehicle is
used to disperse and overlay the foliaye in a film.
For this purpose, we have found that vinyl
acetate/hydroxyethyl acrylate copolymers having an
average range of molecular weights of 30,000 are the
preferred filming agents.
Formulation A for Latex Green_~a~e Coat
Inqredient Ran e Percent by Weiaht Function
Chrome Green (Cr203) 10.0 - 30.0 Pigment
Water Cround Mica 1.50 - 5.00 Extender
Sodium Polyphosphate 0.50 - 1.00 Dispersant
Sodium Carboxymethyl
Cellulose 0.30 - 0.70 Thickener
Methocel~ Antifoam 0.02 - 0.10 Antifoam
Ammonia t0.88 H20
solution) 0.01 - 0.07 Alkalinity
control
Butylacetate 2 ~ 3 Coalescing
solvent
Vinylacetate/
Hydroxyethyl
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Acrylate/Acrylic Acid
45:45:10 Copolymer
(50% solids in H2O
dispersion) 30.0 - 45.0 Film former
Water 30.0 - 45 0
100. 00
This formulation effectively masks the unnatural
faded greyish-green appearance of the foliage
resulting from preservation with humectant ethylene
glycol. The chrome green pigment pleasingly matches
the natural color of many foliages. Other pigments
are used to achieve whatever tint is desired.
Additional artistic effects may be obtained by
further steps of spraying or dip-coating.
Another example of an effective hydrophilic one-
step blend is shown as Formulation B, which is in the
form of a water latex dispersed emulsion. The
formulation is colorless without added pigment.
Pigment is added to the formulation to obtain
coloration, and is selected to achieve the desired
aesthetic effect in the final coated foliage
materials.
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Formulation ~ ~or Latex Emulsion Base Coat-
Colorle~s for Pigment Blends
Inqredient Ranqe Percent by Weiqht Function
Pigment - inert
and variable in
blends
(not part of wt%)
Talc or
Water ground mica 7.0 - 15.0 Extender
Tamol~ 731 1.50 - 2.50 Surfactant
(Rohm and Hass)
Methocel~ Antifoam 0.10 - 0.30 Antifoam
Hydroxyethyl
Cellulose 0.20 - 0.50 Thickener
Butylacetate1.00 - 3.00 Coalescing
Solvent
Ammonia (0.88 H20
Solution) 0.02 - 0.07 Alkalinity
Control
Vinylacetate/Vinyl
"Versatate"~
55:45 Copolymer
(52~ solids in H20
dispersion)40.0 - 60.0 Film Former
Water 25.0 - 40.0
100.00
The indicated percentage component ranges are
exemplary only, and are not intended to be limiting.
Furthermore, all of the listed components in
Formulation A and B need not be used in a particular
blend. For example, an alkalinity control agent is
not always necessary.
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Following the application oE Formulations A or B
or similar blends, foliage may be enhanced in
aesthetic e~fect by further steps of spraying or dip-
coating with a wide variety of colored or clear
coating materials.
Plant materials treated according to the present
invention retain the flexibility of their freshly cut
state. The strength is retained or enhanced,
resulting in a long shelf life and a long useful life
for decorative, scientific or display purposes.
Furthermore, dust and grime adhering to the plant
materials as a result of storage or exposition may be
easily removed by washing with cool or cold water,
optionally containing a weak nonionic detergent or
castile soap, to restore the materials to a clean,
aesthetically attractive state.
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