Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relates to improvements in the
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preparation of ~ilms for use in three-dimensional radio-
graphy and, more particularly, to apparatus and a method for
forming a composite film formed from two films and having a
photographic emulsion on one face and a number of lenticu-
lations on the opposite face.
In U.S. Patents 2,218,227 and 2,562,078, dis-
closures are given about several ways of lenticulating a
photographic film. In the first patent, a thermoplastic
film is heated and passed over a lenticulating drum so that
lenticulations can be formed in one face of the film. The
film is of unitary construction and has a photographic
emulsion on the opposite face thereof. The disadvantage
associated with this technique is that the emulsion is
adversely affected by the presence of the heat applied to
the film. Moreover, the particular film involved, cellulose
acetate, is not dimensionally stable in the presence oE
heat.
The second patent mentioned above describes the
use of a solvent to soften one face of a film, such as
cellulose acetate, before it is moved onto a lenticulating
drum so that lenticulations can be formed in the softened
face of the film. A disadvantage with the technique of this
patent is that the softening of the film by the solvent has
an adverse effect on the emulsion because the cellulose
acetate film is not dimensionally stable, thereby causing
variations in the thickness of the emulsion applied to one
face of the L ilm.
Present day photographic film for X-ray, color and
black and white photographs is typically formed by applying
a photosensitive emulsion to one face of a rilm of a polyester
base material. Such material has very good dimensional
stability; however, it becomes less so when subjected to
heat and it must be heated to be softened sufficiently to
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permit lenticulations to be formed in one of its faces.
Moreover, such lenticulations will be deformed or lost
unless the material is chilled in the impression mold which
forms the lenticulations. Also, the heat which must be
applied to do the molding warps and disfigures the emulsion.
Thus, while polyester based material is highly suited for
use as photographic film, it is not suitable for receiving
lenticulations on one of its faces.
A need has arisen to provide a photographic film
with lenticulations so that the film can be readily exposed
and de~eloped, and the photographic image on the film can
readily be viewed through the lenticulations already applied
thereto so as to obtain a three-dimensional effect. Since
the polyester based material, the typical base for photo-
graphic film, cannot be adequately lenticulated and because
cellulose acetate can readily be lenticulated at room
temperature, it is desirable to have a simple apparatus and
method for forming a composite film which satisfies the
foregoing need.
The present invention is directed to apparatus and
a method for lenticulating a first of two films and lamina-
ting the two films together either before or after the first
film has been lenticulatedO Thus, one of the films which is
coated with a photographic emulsion can be bonded to a
clear, flexible plastic film which is easily lenticulated so
as to form a composite film which avoids the problems
mentioned above with respect to the lenticulating of poly~
ester based photographic film.
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To this end, the apparatus includes a support
having means for lenticulating a first film at one face
thereof and means for laminating a second film to the
opposite face of the first film either before or after the
lenticulation of the first film, the second film having a
photographic emulsion on the face opposite to the face
bonded to the first film. After lamination of the two films
together, the bonding agent between the films is allowed to
set to a permanent condition so that the resulting composite
film has lenticulations on one face and photographic emul-
sion on the opposite face.
More specifically, the invention is apparatus for
forming a photographic film with lenticulations thereon
comprising: a support; means on the support for holding a
1~ supply of a first flexible, plastic film of a material
capable of heing sofened by a solvent; a lenticwlating drum .
rotatably mounted on the support for engaging the first film
at one face thereof for forming lenticulations in the face
after the latter has been softened by a solvent; means
adjacent to the drum for applying solv~nt to said one face
of the first film to soften said face sufficiently to allow
it to be lenticulated when it engages said drum; means on
the support for holding a second flexible film with one face
of the second film having a photographic emulsion thereon;
means on the support for guiding the opposite face of the
second film into face-to-face engagement with the opposite
face of the first film; means adjacent to the path of travel
of the second film for applying a cement to said opposite
face of the second film, whereby the opposite faces of the
films become bonded together when they engage each other and
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the films form a composite film; and means on the support
for receiving the composite after the same has been formed.
In a further aspect the invention is a metho~ ~or
forming a composite film having lenticulations on one face
thereof and a photographic emulsion on the opposite face
comprising: moving a first flexible film along a first path;
applying a solvent to one face of the first film to soften
the same; lenticulating said one face when the same has been
softened; moving a second film along a second path of travel
towards said first path with the second film having a
photographic em~llsion on one fa~e thereof; moving the
opposite faces of the two films into contact with each
other; bonding the two films together when said opposite
faces thereof are in contact to form a composite film; and
]5 advancing the composite film to a station spaced from the
point at which the films move into contact with each other.
The invention is illustrat~d by example in the
accompanying drawings, which are an illustration of one
embodiment of the apparatus of the invention.
In these drawings:
Figure 1 is a side elevational view of the appara-
tus of this invention;
Figure 2 is a crosssectional view taken along line
2-2 of Figure l;
Figure 3 is an enlarged, cross-sectional view of a
portion of the apparatus, showing the elements which len-
ticulate one film and bond the two films together;
Figure 4, which is on the first sheet of drawings,
is an enlarged, fragmentary, crosssectional v:iew of the film
or sheet after it has been lenticulated by the appara-tus;
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and
Figure 5, which is on the first sheet of drawings,
is an enlarged, fragmentary, cross-sectional view of the
lenticulating roller of the apparatus.
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The apparatus for lenticulating and laminating of
the present invention is broadly denoted by the numeral 10
and includes a frame-like support 12 having a pair of
generally parallel side members 14 and 16 disposed above a
floor or other surface by a number of legs 18. As shown in
Figure 1, members 14 and 16 are generally horizontal;
however, they can possibly be inclined without departing
from the scope of the invention.
Apparatus 10 includes a first film supply roller
10 20 near one end 22 of support 12. Roller 20 is adapted to
receive a flexible film or sheet 24 would on the roller,
film 24 being the material to be lenticulated. For purposes
of illustration, this film is of cellulose acetate, a clear,
flexible plastic material, having a thickness of about 10
mils.
Roller 20 is mounted by a shaft 26 in any suitable
manner between side members 14 and 16 for rotation relative
to support 12. For purposes of illustration, shaft 26 and a
number of the other shafts yet to be described are coupled
by ~earing blocks, such as bearing blocks 28, secured to
respective side membe.rs 14 and 16.
Film 24 is movable off roller 20 and beneath an
idler roller 30 spaced from roller 20 and disposed between
members 14 and 16 as shown in Figure 2. From idler 30, film
2~5 24 is movable beneath a second idler 32 and then over and
partially about a pressure roller 34 which bears against a
lenticulating drurn 36. The pressure e~e.rted by roller 34
against drum 36 can be adjusted by adjusting a pair o~
screws 38 engaging bearing blocks 40 shiEtably mounted in
any suitable manner on respective side members 14 and 16.
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Lenticulating drum 36 is provided with an outer
surface o~ the type shown in Figure 5. To this end, such
outer surface includes a series of annular recesses 42 which
are in side-by-side relationship so that ~he resulting
lenticulation on one face of film 24 is as shown in Figure
5. To assist in lenticulating film 24, it is softened by
applying a small amount of solvent to the face to be len-
ticulated. Thus, means 46 is provided for depositing a
small amount of the solvent, such as acetone, to the upper
longitudinal region 52 at the junction of roller 34 and drum
36 as shown in Figure 3. The solvent contacts this face of
the film and is just enough to soften the film to a small
depth so that the face is readily molded by the outer
surface of dr~m 36 to thereby form lenticulations 44 shown
in Figure 4. For purposes of illustration, means 46 comprises
a feeder tube containing acetone 48 which drips from a lower
opening or series of openings S0 into region 52.
As film 24 passes beneath and partially about drum
36, it is lenticulated since it is moldable due to contact
with the solvent. The lenticulations remain in the face of
film 24 as the film leaves drum 36 and moves upwardly along
an inclined path in the direction of arrow 54 (Figure 1).
Near the point of where film 24 leaves drum 36, a
second film or sheet 56 of a suitable photographic film,
such as X~ray film, color film, or ~lack and white film, the
latter being either negative or positive, moves into control
with and is bonded to the ~ace of film 24 which is not
lenticulated. To this end, a supply roller 58 containing
film 56 in roll form is provided between members 14 and 16.
Film 56, after leaving roller 58, passes down and partially
about an idler 60 but then upwardly toward, over and par-
tially about a second idler 62, then downwardl~ and benea-th
and partially about a pressure roller 64 which presses film
56 into intimate contact with the unlenticulated face o~
film 24. Film 56 has an emulsion side which is kept out of
contact with film 24. This emulsion side can be covered by
a paper belt (not shown) to p~otect it.
A mass of flowable cement contained in a trough 66
below members 14 and 16 is transferred by a transfer roller
68 to the opposite side of film 56 as the film is moved
beneath and about pressure roller 64. This cement is used
to bond film 56 to film 24 when they come into intimate
contact with each other at a region denoted by the numeral
70 (Figure 1). The cement is wiped from roller 68 by a
doctor blade to obtain the desired thickness on film 56.
The bonding of films 24 and 56 form a composite
sheet 72 which is then moved upwardly along an inclined path
and about a roller 74 at the upper end of a frame 76 com-
~0 prised of a number of upright channel members 78 as shown inFigures 1 and 2. The length of the path from drum 36 to
roller 74 is sufficient to cause setting of the cement and
thereby the permanent bonding of sheets 24 and 56 together.
Typically, the composite film mo~es under tension during the
dryin~ period a~ a speed of about 1 foot per minute to
assure sufficient setting time for a good bond. After
passing over roller 74, the composite sheet passes down-
wardly and then is wound onto a roller 80 by means of which
it can be taken off apparatus 10 and put into use or stored
for subsequent use.
Means is provided for rotating drum 36, roller 68
and roller 80. For purposes of illustration, a single drive
motor 82 is shown below members 14 and 16 on support 12. A
first belt and pulley assembly 84 couples the drive shaft 86
of the motor with shaft 88 of drum 36. A second belt and
pulley assembly 90 couples drive shaft 86 with shaft 92 and
roller 68. A third belt and pulley assembly 94 couples
drive shaft 86 with shaft 96 of roller 80.
Drum 36 can have any desired number of recesses 42
formed therein. The number of recesses can be in the range
of 100 to 1,000 per inch and typically, the radius of
curvature of each recess 42 is selected to be approximately
one-third of the thickness of the film.
By virtue of the practice of the present inven-
tion, a thin film of transparent cellulose acetate may be
bonded (laminated~ to polyester film base at normal room
temperatures. The sensitive emulsion of the polyester film
may be protected by a paper belt (not shown) held in contact
with the polyester film while the latter is being first
coated with the cement from trough 66 and then bonded to the
cellulose acetate film by pressure and contact. While the
cellulose acetate sheet has been shown and described as
being lenticulated before the bonding of film 56 thereto, it
is to be understood that the lenticulating operation can be
done ~fter the two films are bonded together. In the latter
case, the various rollers, idlers and drums 36 would be
arranged so that the lenticulations would be formed while
the cement bonding the two films together ls setting or
after the cement has set.
The laminating and lenticulating may be performed
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continuously in the present invention. In this way, a
relatively large amount of material can be processed in a
minimum of time.
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