Note: Descriptions are shown in the official language in which they were submitted.
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IM~ROVED APPARATUS FOR PREPARING
STRIPED SHEET MATERIAL CONTINUOUSLY
This invention relates to an apparatus for continuous-
ly producing striped sheet material and more particularly pertains
to the apparatus for the manufacture of plastic sheet material
having substantially parallel abutting stripes of a wide variety
of shapes and colors and various combinations o same. The
present invention is particularly adaptable to the production of
thermosetting plastic sheet material having integral, substantially
parallel abutting colored stripes. The thermoset plastic sheet
produced by this process can be and preferably is reinforced with
fibers and can be either opaque or translucent with either opaque
or translucent colored stripes. The strips produced in this
invention are always narrower than the width of the plastic sheet
material and will contrast in appearance with the next adjacent
stripe in at least one respect in regard to color, translucency,
or opaqueness, etc. The adjacent stripes m~st be different in
color, translucency, etc. from the next adjacent stripe.
The apparatus of this invention relating to the pro-
duction of stripes in plastic sheet material is an improvement
over the apparatus described in our U.S. Patent No. 3, 716, 431.
According to the present invention, striped sheets or
plates comprising a polymeric resin are produced continusously
by a process wherein a curable synthetic resin which may be in the
form of a liquid or paste containing one or more polymerizable or
curable monomeric compounds is passed between moving surfaces
which are substantially parallel in the direction of the movement
and have subgtantially no relative motion, and the monomeric
constituents of said liquid or paste are polymerized between said
surfaceg by the action of heat, light, or other type of radiant
energy, with or without the application of pressure.
The continuou~ production of sheet material, and
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particularly plastic sheet material, if ~urther described in U.S.
2,784,763, for instance. In this prior art process a composite
sheet material is produced by moving lo~gitudinally a lower surface
film or web, depositing on this web a heat settable liquid resin~,
placing in the liquid resin stranded reinforcing material, dis-
placing the air in the reinforcing material with liquid resin,
then covering the mixture of liquid resin and reinforcing material
with an upper film or web, applying pressure to the upper web
and lower web to consolidate the mixture of liquid resin and rein-
forcing material and thus forming a composite sheet, moving thecomposite sheet longitudinally through a heating zone causing the
resin to set and during the movement through said heating zone
engaging the opposite surfaces of the composite sheet and shaping
it into a desired form in a longitudinal direction.
U.S. Patent No. 2,927,623 describes an apparatus for
continuously producing a composite sheet of reinforced plastic
material. The apparatus of this patent operates by feeding
through the machine a carrier surface vheet of cellulose film
such as cellophane onto which a measured quantity of settable
resin in liquid form is deposited and spread evenly with a doctor
blade. The edge portions of the sheet are raised so as to confine
the resin to the central portion of the sheet. Chopped strands
of fibrous material are fed onto the resin and simultaneously
compacted and pressed into the resin by a plurality of threads
extending lengthwise of the sheet. As the loose fiber is held
compacted by such threads, a cover surface sheet is laid on the
resin and fiber mi~ture, the opposite edges of the surface film
are glued together to form a flat tube containing the resin and
fiber mixture, and such composite sheet it passed between rolls to
squeeze out the air and establish the thickness of the sheet. The
~heet thus formed is then passed through slots of fixed width during
setting of the resin, which pre~erably is expedited by passing the
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sheets through an oven. After resin has set, the longitudinal
edges of the continuous sheet may be trimmed, and the sheet which
is composed of chopped strands of fibrous material such as glass
fiber embedded in a matrix of cured synthetic resin cut into
desired lengths.
U.S. Patent No. 3,077,000 describes an improvement
for preparing longitudinally contoured sheet material described in
U.S. Patent No. 2,784,763, comprising an apparatus for providing
transversely contoured, continuously formed sheet material.
Lines, stripes and different designs have been placed
upon sheet objects by stencils, printing and various other means.
There are some materials upon which printing is unsatisfactory
and stencils are not adaptable. Patterns can be painted or other-
wise coated onto the surface of a panel after the panel is produc-
ed but such a process is an expensive additional operation and
usually produces a pattern which can easily be worn or chipped off
the panel. Panels can also be made with an inserted paper or
other inserted sheet material on which there is a printed pattern.
The inserted sheet material is expensive, the process for inserting
it is expensive, and lack of complete soaking and integration into
the plastic ~nel permits water absorption and blooming.
It is desirable to provide means whereby abutting
colored stripes may readily be placed upon continuously formed
sheets of reinforced plastic material by flowing paint, lacquer
or the like through abutting restricted openings onto one or both
of the upper and lower webs and partially curing the abutting
stripe or stripes thus formed before addition of the curable resin
and fibers to the sheet forming apparatus.
The primary object of this inven~ion is the provision
of a striping apparatus in which the size, number, color and
arrangement of the stripes may be adjusted readily and closely
abutting parallel stripes can readily be produced. Another
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object isto provide an easily assembled striping apparatus which
is of a simple and economical construction.
Thus, in accordance with the present teachings,
an improvement is provided in an apparatus for continuously
producing a plastic sheet of predetermined cross-section, which
comprises means for providing a moving flexible carrier web, means
for depositing liquid resin on the carrier web, means for de-
positing fibrous-reinforcing material onto the liquid resin
and lowering the reinforcing material into the liquid resin,
means for placing a flexible cover web on the liquid resin and
reinforcing material, forming means of predetermined cross-
section, means to pull the flexible webs with the partially
cured resin therebetween through the forming means and curing
means disposed adjacent to the forming means to substantially
completely cure the resin while it is been moved through
the curing means. The improvement in such apparatus comprises
the inclusion of at least three adjacent puddle rails removably
and slidably disposed to ride on the moving carrier web the
forward end of said puddle rails abutting a knife coater
located just above the carrier web with means for continuously
supplying contrasting liquid striping materials between the
puddle rails onto the surface of the carrier web.
Our apparatus produces a multiple striped pattern
created by a dyed or pigmented resin system, which pattern is
chemically bonded with the panel resin and is integral within
the panel. This pattern cannot be chipped off the panel, nor
will it flake off because it is an integral part of the panel.
Internal blooming or separation of the pattern cannot occur.
The first step in the striping process is that of
depositing, by means of our striping apparatus more completely
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described herein, at least two coatings of contrasting color or
- opaqueness having a definite controlled thickness and specific
controlled width onto the carrier sheet and/or the cover sheet
such that they form abutting, contrasting stripes longitudinally
with the direction of formation of the panel. A plurality of such
abutting stripes can be used to form a variety of geometric patterns
in the finished panel. Special forms of our striping apparatus
deposit the initial coating on the carrier sheet. These stripers
are assembled to incorporate side-retention knife means as well
as forward metering or doctoring means for the production of each
stripe.
The striping apparatus of this invention is provided
for applying at least two abutting stripes of at least two
contrasting liquid materials, supplied from liquid sources, onto
a web member having relative movement in a predetermined direction
with respect to a web-engaging surface of the striping apparatus
comprising at least three puddle rails abutting at right angles
to a knife coater, the puddle rails being adjusted to ride on the
web member surface to form areas of web surface between adjacent
puddle rails and the knife coater in which the liquid materials
can be deposited to form stripes as the liquid material passes
through the knife coater with the movement oi the web material,
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preferably the outboard p le rails being angled outwardly at
their downstream ends with respect to the direction of relative
movement of the web and applicator to prevent or minimize trans-
verse leakage of the liquid material.
The thickness of the stripes applied in this manner
depends primarily upon the setting of the knife coater or doctor-
ing blade in relation to the surface of the web, viscosity of the
liquid stripe material, and the speed of movement of the web.
An illustrative doctor blade setting is one that would provide a
gap of between 0.001-0.100 inch, through whi~h the liquid stripe
material flows.
The puddle rails and doctor blade combination device
may be maunted in a~y suitable manner and the distance between
adjacent puddle rails can be varied and any number of puddle rails
may be used in a given operation.
The general characteristics of the apparatus and
process of the present invention will be further illustrated in
the accompanying drawings wherein:
Figure 1 is a side elevation view partly in section
of the apparatus of this invention.
Figure 2 is a top perspective view partly in section
of the forward part of the apparatus of this invention.
Figure 3 is a partial to~ plan view partly in aection
of the strrping apparatus of this inve~fion.
Figure 4 is a sectional view taken on line 4-4 of
Figure 3.
Figure 5 is a sectional view taken on line 5-5 of
Figure 3.
Figure 6 is a sectional view taken on line 6-6 of
Figure 3.
Figure 7 is a sectional view taken on line 7-7
of Pigure 3.
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Figure 8 is a sectional view taken on line 8-8 in
Figure 1.
Figure ~ is a sectional view taken on line 9-9
in Figure 1.
Figure 10 is an end elevation view partly in section
of one striper of the apparatus.
Figure 11 is a side elevation view partly in section
of the strpper of Figure 10.
Figure 1 is a cross-sectional over-all view of the
striping and panel-forming apparatus including the lower carrier
sheet 1 which is unrolled from roll 2 and travels in a plane along
table 3. The carrier sheet 1 may be paper or a plastic of a
character which may be stripped from the finished composite
sheet and conveniently may be a cellulose film such as Cellophane~.
If the surface carrier sheet material is shrunk by heat as celloph-
ane is it can be passed through a heating zone before material
is placed on it. In this zone heat may be supplied by lamps 4
of the infrared type. On the forward moving lower carrier sheet
1 abutting stripes of colored liquid curable material are contin-
uously deposited from between at least three pud~dle rails 5. Thecolored liquid stripes are preferably composed of contrasting dye-
or pigment-containing heat curable liquids or pastes of controlled
viscosity which are continuously fed between the puddle rails 5
from one or more reservoirs 6 through a conduit 7. A typical
liquid stripe material is made up of 70 parts by weight of
neopentyl glycol-orthophthalic-maleic polyester compounded with
styrene, butyl methacrylate and ultraviolet absorber, 30 parts
by weight of propylene glycol-orthophthalic-maleic polyester
compounded with styrene and ultraviolet absorber and modified to
; 30 reduce sensitivity to air inhibition on curing, 8 parts by weight
of a plasticizer, 1 part of silica aerogel, 1 part silicone
resin, 4-9 parts pigment, 0.4 part t-butyl perbenzoate and 0.3
1~4;~615
part methyl ethyl ketone peroxide. The colored stripes are then
at least partially cured with a heat curing means such as an
infrared heater 8 so that it becomes insoluble and no longer will
flow. It is necessary in this step to gel the stripe material
enough so that it will not intermix and flow when it contacts
the basic panel resin or into the adjacent abutting stripe
material and preferably the stripe material is not completely
cured until it is co-cured with the basic panel resin. Next there
is deposited on the forwardly moving carrier 1 from a spreading
means such as a trough 9 a measured quantity of polymerizable
resin such as a liquid unsaturated polyester composition. A
typical liquid polyester is composed of 100 parts by weight of
propylene glycol-orthophthalic-maleic polyester, compounded with
styrene and methyl methacrylate monomers and an ultraviolet
absorber, 10 parts of hydrated aluminu~ oxide, 0.75 part of
titanium dioxide, O.9 part of benzoyl peroxide and 0.3 part of
cumen hydroperoxide. The fibrous reinforcing component of the
plastic sheet can be a continuous web of fibers 10 such as that
prepared by continuously chopping glass fibers and randomly
depositing them on an endless belt in a plenum chamber 11 as is
well known in the art. The fiber mat 10 is drawn by the belt 12
and is usually in the form of a loose stack which is distributed
uniformly acDoss the width of the belt and distributed onto the
layer of resin and abutting stripes being carried by the lower
sheet 1. If desired, tensioning threads 13 as more fully described
in U.S. Patent No. 2,927,623 may be used and are drawn by roller
14 over the upper side of the pile of fibers carried by sheet 1 to
press the fibers down intothe liquid polyester to a uniform
thickness. A cover sheet or web 15 which is preferably of the
same material as carrier sheet 1 is dispensed from a roll 16
between pinch roll~ 17 and 17~ and can be preheated by heating
means such as an infrared lamp 18. Stripes may be deposited on
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the cover sheet 15 by employing the apparatus and procedure just
described for doing this on the carrier sheet 1. Thus, stripes
can be deposited on either carrier sheet 1, cover sheet 15, or
both; and when stripes are produced on both, they may be arranged
in or out of register in the final cured sheet material. The
surface of the web 15 becomes the under surface of the cover sheet
as it passes between pinch rolls 17 and 17!. Means are used to
squeeze the air from the composite sheet structure thus formed
as is more fully described in U.S. Patent No. 2,927,623. The
composite sheet, composed of a flattened tube of the two edge-
sealed surface sheets containing the fibers, resin and threads,
passes through a forming oven 19 where it is formed and cured.
During its passage through the oven the sheet may be formed into
a c~oss-sectional shape of any desired shape. This operation can
be carried out by passing the sheet between ~o~m~g members or dies
as is more fully described in U.S. Patent No. 2,927,623. When the
finished composite sheet emerges from the oven it may be cut ~
the desired width by edge trim saws 20 and to the desired length
by a traveling saw 21 after which the several sheet sections 22
are conveyed to a stacking area. If desired, means also may be
provided after oven 19 for stripping the carrier and cover sheets
from the finished composite sheet said sheet having the glass fibers
disposed beneath the surface of the cured synthetic resin matrix.
Forward movement of the sheet material through the apparatus of
Figure ls is effected slowly and uniformly by cooperating endless
track~, endless tread belts, draw rolls or other pulling means
well known to those skilled in the art and more fully described
in U.S. Patent No. 2,784,763. The pulling means is preferably
located between the saws 20 and 21.
Pigure 2 is a top perspective view showing somewhat
diagrammatically the apparatus for initially forming the stripes
and forming the composite sheet, parts being broken away. The
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puddle rails 5 float on the lower carrier sheet 1 as the carrier -
sheet passes over the smooth, flat table surface 3. The flow of
liquid striping material from the reservoir 6 to the area on the
carrier web 1 between puddle rails 5 can be controlled by a
metering valve means 24. The wide stripe 23 and narrower stripe
23' are deposited on the lower carrier sheet 1 and are not yet
cured by heat but are su~ficiently viscous to hold their shape.
The puddle rails 5 are restrained from forward longitudinal
movement by a suitable doctor blade 25 which is secured at each
of its ends to the sides of the table 3 by means of a bracket 26.
In Figure 3, which is a top sectional view taken above
three puddle rails, the stripes 23 and 23' appear and puddle rail
5' is preferably held at a slight angle against the doctor blade
25.
The stripe process is carried out by depositing a
coating of a definite controlled thickness and specific controlled
width onto the lower carrier sheet or upper cover sheet, or both,
so that at least two longitudinal abutting stripes are continuous-
ly formed on the sheet. ~he plurality of stripes can be used to
form any variety of parallel geometric patterns in the sheet.
Figure 6 shows stripes 23 and 23' as they are produced
just downstream of the doctor blade.
Figure 7 shows stripes 23 and 23' which have flowed
together just prior to being partially cured.
Figure 8 shows stripes 23 and 23' which have been
partially cured and sandwiched between carrier web 1 and contin-
uous web of fibers 10.
Figùre 9 ~hows the completed panel structure just
before final curing. The panel structure includes the lower
carrier web 1, the stripes 23 and 23', the resin impregnated
continuous web o~ fibers 10 and the upper carrier web 15.
Figure 10 shows a rod 27 with slidable clamping
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devices 28 on which are secured the puddle rails 5.
Figure 11 shows a side view of the same part of the
apparatus as is shown in Figure 10.
The invention includes the production of striped,
fiber-reinforced polyester structures wherein a mixture, consist-
ing essentially of tl~ at least one organic linear polymeric
ester containing recurring ethylenic unsaturation, t2) at least
one addition-polymerizable ethylenically unsaturated organic
monomer, and (3) reinforcing fibers, is subjected to additional
polymerization conditions e~fective to produce a striped, cured,
fiber-reinforced polyester structure.
Unsaturated polymeric esters suitable for use in the
invention for both the sheet forming resin and the strip material
include those prepared by condensing under p~lymerizing conditions
either ~1~ an ethylenically unsaturated dicarboxylic acid with a
diol containing no ethlylenic unsaturation or t2~ a dicarboxylic
acid containing no ethylenic unsaturation with an ethylenically
unsaturated diol, or most commonly, ~3~ a mixture of ethylenically
unsaturated dicarboxylic acids and dicarboxylic acids containing
no ethylenic unsaturation with a diol containing no ethylenic
unsaturation. Stable diacylchlorides, diesters or anhydrides of
the dicarboxylic acids which are available can be and are often
substituted in whole or in part ~or the acid.
Among the ethylenically unsaturated dicarboxylic acids
and derivaties thereof which are commonly employed can be mentioned
fumaric acid, maleic acid and its anhydride, citraconic acid,
me~aconic acid, itaconic acid and endomethylene tetrahydrophthalic
acid. Among ~he dicarbo~ylic acids and derivatives thereof
containing no ethylenic unsaturation which are commonly employed
can be mentioned phthalic acid and its anhydride, adipic acid,
sebacic acid, ispphthalic acid, ter~phth~lia acidj malonic-acid
and glutaric acid~
A frequently employed ethylenically unsaturated diol
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is 2-butene-1, 4-diol, while among the commonly employed diols
containing no ethylenic unsaturation can be mentioned ethylene
glycol, propylene glycol, diethylene glycol and dipropylene
~lycol. As will be obvious to thoee skilled in the art, varying
the proportions and nature of the ethylenically saturated and
unsaturated reactants in these condensations affects the number
of carbon-to-ca~bon double bonds in a given polymer chain length
available for cross-linking by addition polymerization means.
Among ~he addition polymerizable compounds most
commonly employed as cross-linking agents in combination with the
above-described polyesters can be mentioned styrene, diallyl
phthalate, methyl methacrylate and triallyl cyanurate. Other
ethylenically unsaturated cross-linking agents more or less fre-
quently employed in these operations include alpha-methyl styrene,
divinyl benzene, vinyl toluene, allyl diglycolate, methyl acrylate,
ethyl acrylate, ethyl methacrylate, vinyl acetate, acrylonitrile,
diallyl maleate, vinyl phenol and allyl carbamate. Frequently
re than one of the above cross-linking agents is employed in the
same mixture, depending on the properties desired in the final
structure and its ultimate use. In general their physical charact-
eristics are such that these resins produce a broad, transparent
or translucent product by polymerization, but in order to provide
toughness and strength, fibrous reinforcing material is preferably
embedded in such resins. In a sheet four feet wide, eight feet
long and one-sixteenth of an inch thick, for ins~ance, thrrty
- percent by weight of the sheet can be reinforcing material and
seventy percent resin, although the proportions of resin and fiber
can be varied considerably.
A polymerization catalyst may be incorporated into the
unsaturated polymeric ester of this invention. Suitable polymer-
ization catalysts are peroxides such as benzoyl peroxide, acetyl
peroxide, t-butyl peroxide, di-t-butyl peroxide, methyl ethyl
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ketone peroxide, lauryl peroxide, cumene hydroperoxide, cyclo-
hexane peroxide and the like: azo compounds such as azobisisobut-
yronitrile and the like. Accelerators or promoters such as cobalt
naphthenate, phenyl phosphinic acid, p-toluene sulfonic acid,
and some tertiary amines such as dimethyl sniline, are also
frequently employed. The polymerization or curing reaction of
the monomeric compound can also be initiated by radiant energy
such as light, X-rays, or nuclear radiation which may or may not
be used in con~unction with chemical initiators and activators
which are all well known to those skilled in the art.
~ he resin preferred for use in the manufacture of sheet
material produced by the present process is one of low viscosity
which will readily impregnate the reinforcing material and on
exposure to heat will set into a hard, dense, infusible state.
For transparency a clear, light-stable resin is desirable. For
decorative purposes a light colored resin which may be tinted by
the addition of pigments or dyes is desirable. For clarity a
resin which has an index of refraction closely matching that of
the reinforcing material is desirable. All these characteristics
may be found in a family of resins-called "p~lyesters" which are
well known to be settable by the process of polymerization.
Reinforcing fiber is preferably additionally incorpor-
ated into the unsaturated polyester mixture. Any suitable rein-
forcing fiber may be employed, such as, for example, asbestos,
nylon, cellulosic and the like mineral and organic fibers. Glass
reinforcing fibers are preferred, particularly from the strength-
versus-cost standpoint. Fibrous glass is availa~le for reinforcing
structures in the form of cloth, yarns, mats, rovings, milled
fiber~, parallel strands, surfacing mats and loose fibers. The
~election of the particular form in ~hich the glass fibers are to
be used and the qua~tity thereof in proportion to the other
ingredients in the mixture permits wide latitude and is a further
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163 4Z615
means of varying the properties of the final structure, in
addition to varying the proportions and ~pecific nature of the
polyester and cross-linking agents, respec~ively.
Glass mat is composed of a number of layers of glass
fiber bundles, crossing at random and banded loosely together
with resin. Glass cloth or other woven fibers may also be used
; in the apparatus to manufacture reinforced resin sheet.
Fillers such as pigments, clays, mica, silica, talc,
etc., can be incorporated into the unsaturated polyester-fiber
mixture prior to curing.
The material used for the surface elements or upper
and lower carrier webs should be thin, nonporous, inexpensive and
sufficiently strong to carry the resin and reinforcing fiber
material entirely through the sheet forming apparatu~ without being
ruptured. It has been found that cellulose film, that is Celloph-
ane ,meets these requirements, although it is entirely feasible to
u~e other materials such as cellulose acetate film, polyvinyl .
chloride film, vinyl chloride/vinyl acetate copolymer film and
polyethylene film for instance, which like Cellophane will part
from the resin sheet, or polyester film and polyvinyl fluoridefilm
more f~lly described in U.S. Patents Nos. 3,284,277 and 3,257,266
which will adhere to the resin and become an integral part of the
finished sheet imparting weather stability and other desirable
properties to the sheet. Endless belts of a material such as
stainless ste~l can be used for surface elements in the process
of the present invention.
Stripping or release agents, ~or instance surface
active agents, may be applied to the carrier webs or incorporated
into the monomeric compounds to facilitate the separation of the
polymerized, finished composite sheet from the moving surfaces.
It will be apparent that the motion of the moving
~urfaces, while remaining substantially parallel, may, with
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advantage, be so arranged that the surfaces~are brought slightly
closer together in passing through the region in which polymer-
ization is taking place. In this way it is possible fo follow
up the shrinkage of the polymerizing mass, that is the sheet.
During its passage through the oven the sheet may be
formed into any desired cross-sectional shape. This forming
operation is accomplished by passing ~he sheet between forming
members or dies of complemental contour. Pairs of these members
may be located a few feet apart and the width of the members ia
the direction of travel of the sheet may be of the order of one
inch. The lower member are fixedly mounted and the upper member
of each pair can be raised and lowered by suitable mechanism.
The novel striped sheet material embodied herein is
useful in a wide variety of ways, particularly as a material-in
the construction of walls, room dividers, doors, sky lights, privacy
fences, patio covers, windows, and the like.
It is to be understood, however, that while the
invention as herein described is concerned with a continuous length
of sheet material that various modifications might be made ~ven
to the extent of treating individual pieces of material by the
method and essential means shown without departing from the point
of the invention.
It is todbe understood, also, that while we have
herein shown and described particular embodiments of our invention
that changes in form and construction may be made within the scope
of the appended claims.
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