U.S. patent application number 11/336993 was filed with the patent office on 2006-06-08 for production apparatus of multilayer coating film.
This patent application is currently assigned to FUJI PHOTO FILM CO., LTD.. Invention is credited to Shuichi Endo, Atsushi Kodou, Kazuhiko Nojo, Tomonari Ogawa.
Application Number | 20060121202 11/336993 |
Document ID | / |
Family ID | 19191192 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060121202 |
Kind Code |
A1 |
Endo; Shuichi ; et
al. |
June 8, 2006 |
Production apparatus of multilayer coating film
Abstract
A method for forming multiple coating layers produces a coating
construction that has flexibility corresponding to the number of
layers of multiple coating layers, by which a multilayer coating
film can be produced with small film thickness without adherence of
dust to a film surface, a drying fault such as unevenness induced
by drying-wind on the film surface, or a coating fault such as a
level variation and a streak. The multilayer coating film has a
coating surface state of high quality with coating thickness
deviation of 3% or less. In the method, a belt-like substrate is
continuously fed. A coating/drying step follows, with multiple
steps performed in a single unit. A plurality of coating layers are
formed by sequentially performing the coating/drying step by
multiple units. Finally, the belt-like substrate with the multiple
coatings is continuously wound.
Inventors: |
Endo; Shuichi;
(Fujinomiya-Shi, JP) ; Nojo; Kazuhiko;
(Fujinomiya-Shi, JP) ; Ogawa; Tomonari;
(Fujinomiya-shi, JP) ; Kodou; Atsushi;
(Fujinomiya-Shi, JP) |
Correspondence
Address: |
YOUNG & THOMPSON
745 SOUTH 23RD STREET
2ND FLOOR
ARLINGTON
VA
22202
US
|
Assignee: |
FUJI PHOTO FILM CO., LTD.
MINAMI-ASHIGARA-SHI
JP
|
Family ID: |
19191192 |
Appl. No.: |
11/336993 |
Filed: |
January 23, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10341245 |
Jan 14, 2003 |
|
|
|
11336993 |
Jan 23, 2006 |
|
|
|
Current U.S.
Class: |
427/372.2 ;
118/65; 118/66; 118/67 |
Current CPC
Class: |
B05D 7/584 20130101;
G02B 1/11 20130101; F26B 13/12 20130101; G02B 1/10 20130101; B05D
7/586 20130101; B05D 2252/02 20130101; F26B 13/10 20130101 |
Class at
Publication: |
427/372.2 ;
118/065; 118/066; 118/067 |
International
Class: |
B05C 11/00 20060101
B05C011/00; B05C 13/02 20060101 B05C013/02; B05D 3/02 20060101
B05D003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 15, 2002 |
JP |
2002-006152 |
Claims
1. A method for forming a multiple coating layers, comprising:
continuously feeding a belt-like substrate; performing a
coating/drying step in which following steps (i) to (iv) are
performed in a single unit; (i) introducing the belt-like substrate
into a casing and continuously transferring the belt-like substrate
to a coating zone; (ii) forming a single coating layer by applying
a coating solution onto the belt-like substrate while performing
the continuous transferring; (iii) drying the single coating layer
while performing the continuous transferring; and (iv) leading the
belt-like substrate out of the casing; forming a plurality of
coating layers by sequentially performing the step of
coating/drying by a plurality of units, each of which is the single
unit, arranged a number of times being equal to a number of the
plurality of coating layers; and continuously winding the belt-like
substrate on which the multiple coating layers are formed.
2. The method for forming a multiple coating layers according to
claim 1, further comprising: forming a down flow of clean air by
exhausting a clean air blown from an air inlet port formed at a
ceiling surface of the casing through an exhausting port formed at
a bottom surface of the casing.
3. The method for forming a multiple coating layers according to
claim 2, wherein in transferring the belt-like substrate in at
least one of the steps of (i) introducing, (ii) forming, and (iv)
leading, the belt-like substrate is transferred in a box-shaped or
tube-shaped transfer path case provided in the casing along the
transfer path, and a part of clean air, which is blown from the air
inlet port at a ceiling surface, is introduced from an air
introduction port formed at inlet port side of the transfer path
case and the part of clean air is exhausted through an air exhaust
port formed at exhaust side of the transfer path case.
4. The method for forming a multiple coating layers according to
claim 3, wherein an inside pressure of the transfer path case is
kept higher than an outside pressure.
5. The method for forming a multiple coating layers according to
claim 3, wherein a plurality of pass rollers are placed in the
transfer path case along the transfer path, and only a roller shell
portion of the plurality of pass rollers is enclosed by the
transfer path case.
6. The method for forming a multiple coating layers according to
claim 4, wherein a plurality of pass rollers are placed in the
transfer path case along the transfer path, and only a roller shell
portion of the plurality of pass rollers is enclosed by the
transfer path case.
Description
[0001] This application is a division of co-pending application
Ser. No. 10/341,245, filed on Jan. 14, 2003, the entire contents of
which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a production apparatus of a
multilayer coating film, and particularly to a production apparatus
of a multilayer coating film which produces function films such as
a wide view angle film and an antireflection film that are used for
liquid crystal displays.
[0004] 2. Description of the Related Art
[0005] Recently, various kinds of function films such as a wide
view angle film and an antireflection film are widely used for a
liquid crystal display. This function film needs to have a small
film thickness, no adherence of dust to a coating surface, no
coating fault such as a level variation and a streak, and no drying
fault such as unevenness on the surface induced by drying-wind, and
it further needs to have a high quality coating surface with a
coating thickness deviation of 3% or less. The function film
comprises multiple coating layers, and the multiple coating layers
are made by applying coating solutions with organic solvents a
plurality of times to a flexible substrate (hereinafter referred to
as a web).
[0006] Since the above-described high quality is demanded, the
function film with the high quality coating surface cannot be
efficiently produced with an ordinary coating device. For example,
with a coating device equipped with one coater and a dryer, a web
has to be repeatedly passed through the coating device as many
times as the number of layers to perform multilayer coating, thus
causing the disadvantage that a large variation occurs to the
quality, and production efficiency becomes extremely low. Only in
terms of quality, it is considered to perform multilayer coating
with a spattering device, but the production speed is extremely low
with 1 m/min, and the production cost is too high, thus making it
difficult to be adopted. There is a multilayer coating apparatus
for performing multilayer coating by placing a plurality of sets of
coating devices including coaters and dryers in layers, where a web
is continuously transferred from the coating device on the upper
layer to the coating device in the lower layer to perform
multilayer coating. However, the multilayer coating apparatus is
limited to three layer coating at the maximum in terms of
operability because a delivery device and a winder for the web
should not be far from the coater. This apparatus has the
disadvantage that a burden of cleaning the coating devices, an
operation of passing the web through the devices and the like is
too large, and too much loss of time concerning the maintenance is
required.
[0007] From the viewpoint of efficient multilayer coating, a
gravure printing apparatus having three sets to ten sets or more at
the maximum of coaters and dryers for one printing apparatus is the
most efficient apparatus.
[0008] However, in the gravure printing apparatus, it is difficult
to build a preferable and flexible coating construction
corresponding to the number of layers of the multiple coating
layers, and the gravure printing apparatus is insufficient as a
multilayer coating film production apparatus for a function film
which is demanded to have the above-described high quality in terms
of coating, drying, dust prevention and handling. Accordingly, the
fact is that there is no production apparatus of the multilayer
coating films, especially, no preferable production apparatus of
the multilayer coating films which efficiently produces high
quality function films such as wide view angle films and
antireflection films used for liquid crystal displays.
SUMMARY OF THE INVENTION
[0009] The present invention is achieved in view of the
above-described circumstances, and has its object to provide a
production apparatus of a multilayer coating film preferable for
producing various kinds of function films such as a wide view angle
film, and an antireflection film, since it is capable of easily
building a coating construction with flexibility according to the
number of layers of the multiple coating layers, and is capable of
producing a multilayer coating film with small film thickness,
without adherence of dust to the film surface, a drying fault such
as unevenness induced by drying-wind on the film surface, and a
coating fault such as a level variation and a streak, and further
with a high quality coating surface state with a small coating
thickness deviation.
[0010] In order to attain the aforementioned object, the present
invention is directed to an apparatus for producing a multilayer
coating film in which a plurality of coating layers are formed on a
web, comprising: a production chamber; a delivery device and a
winder of the web which are placed on a floor surface of the
production chamber; and a plurality of coating devices which are
arranged between the delivery device and the winder of the web, a
number of the plurality of coating devices being equal to a number
of the plurality of coating layers, each of the plurality of
coating devices being constructed to be a unit by integrally
incorporating at least a feed roller for transferring the web along
a transfer path, a coater provided at the transfer path to form one
of the plurality of coating layers on the web, and a dryer for
drying the one of the plurality of coating layers inside a casing
having an inlet port and an outlet port for the web.
[0011] According to the present invention, the coating device is
constructed as a unit which makes it easy to provide a plurality of
the same devices and combine it with other devices by integrally
incorporating at least the feed roller, the coater and the dryer in
the casing, and the coating device is given a unit function as an
independent device, whereby the production apparatus of the
multilayer coating film can be constructed by only suitably placing
as many coating devices as the number of layers of the multiple
coating layers which are formed on the web between the delivery
device and the winder. This makes it possible to build the
production apparatus of the multilayer coating film which
corresponds to production of the multilayer coating film with any
number of layers with one transfer from the delivery of the web to
the winding. Accordingly, the production efficiency can be
improved, and the production cost can be reduced.
[0012] Preferably, the production apparatus of the multilayer
coating film further comprises: a dust removing device which is
constructed as a unit by integrally incorporating at least a feed
roller for transferring the web along a transfer path, and a dust
remover provided at the transfer path to remove dust on the web
inside a casing having an inlet port and an outlet port for the
web; a heat treatment device which is constructed as a unit by
integrally incorporating at least a feed roller for transferring
the web along a transfer path, and a heat treatment machine
provided at the transfer path to thermally treat the web inside a
casing having an inlet port and an outlet port for the web; and a
surface inspection machine which is constructed as a unit by
integrally incorporating at lease a feed roller for transferring
the web along a transfer path, and a surface inspection machine
provided at the transfer path to inspect a coating surface state of
the web, wherein: the dust removing device is placed between the
delivery device and the plurality of coating devices; and the heat
treatment device and the surface inspection device are placed in
order from an upstream side in a transfer direction of the web
between the plurality of coating devices and the winder.
[0013] According to the present invention, a series of function
film production route from delivery of the web to winding is
formed. Accordingly, the production apparatus of the multilayer
coating film, which produces a function film such as a wide view
angle film and an antireflection film, is easily constructed. By
providing a UV treatment machine for performing UV treatment for
the coating layer after drying at the position after the dryer, the
apparatus can suitably correspond to the case in which the cured
resin contained in the coating solution is a UV cure resin, and in
the case in which it is a thermosetting resin.
[0014] Concerning handling of the web which is important to prevent
the coating fault such as a level variation and a streak, the feed
roller is provided at each device to make tension of the web cut at
each device. Hence, even if tension variation occurs to one of the
devices, an adverse influence of the tension variation is not given
to the devices before and after the device.
[0015] Concerning dust prevention, which is important to prevent
dust adhering to the film surface, a fan filter unit is provided at
an air inlet port formed at a ceiling surface of a casing of each
device, an air exhaust port is formed at a bottom surface of the
casing, and clean air blown into the casing from the fan filter
unit is exhausted from the air exhaust port. As a result, a down
flow of clean air can be formed in the casing of each device, and
cleanliness inside the casing can be improved. In addition, the fan
filter unit is provided at each casing, and therefore cleanliness
according to the treatment of each device such as dust removing,
coating, surface inspection and the like can be formed inside the
casing.
[0016] Further, a transfer path in each device is enclosed by a
transfer path case, which has an inlet port and an outlet port for
the web and has an air introduction port and an air exhaust port,
along the transfer path, and clean air is supplied into the air
introduction port. As a result, the transfer path in which the web
is exposed to dust the most easily can be made a slim transfer path
case with a small volumetric capacity, which is corresponding to
the transfer path, therefore making it possible to prevent the wind
speed of the clean air supplied into the transfer path case from
decreasing, and a dead zone where clean air does not flow from
occurring. As a result, dust prevention for the web can be
performed with a small amount of clean air, and an air amount
supplied into the casing can be reduced, and the total air amount
can be made small.
[0017] As for the dryer important to prevent a drying fault such as
unevenness induced by drying-wind on the film surface, the dryer is
divided into three or more drying zones along the transfer
direction of the web, a supply device which supplies dry air and an
exhaust device are provided at each drying zone, and
micro-differential pressure gauges to perform static pressure
management between the dry zones are provided. As a result, it is
possible to individually set the dry air amount and temperature and
relative humidity for each drying zone, and a drying condition
corresponding to a film surface strength of the coating layer can
be selected, thus making it possible to prevent unevenness induced
by drying-wind. By performing static pressure management between
the drying zones, coming and going of drying air from and to each
of the zones can be eliminated as much as possible, the precision
of set condition of each zone can be enhanced.
[0018] The coater which is important to form a suitable layer for
each layer in the multiple coating layer is any one of a direct
gravure coater, a reverse coater, a kiss coater, a microgravure
coater, a bar coater, and an extrusion coater, and the coater is
provided to be replaceable. As a result, even when the coating
condition of each layer constructing a multilayer, for example,
kinds of solution, coating amount, coating method (kind of coater)
differ, the apparatus can easily correspond to it.
[0019] Further, the coater inside the coating device is placed to
be located on a floor surface of the casing of the coating device
or near the floor surface. As a result, since all of the delivery
device, coater, and the winder can be arranged on the same floor,
operability in attaching required a raw roll of the web to the
delivery machine, winding handling of the multilayer coating film
being the produced product to the winder, replacing operation of
the coater, transportation of the coating solution and the like
according to the types of the multilayer coating film to be
produced can be extremely improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The nature of this invention, as well as other objects and
advantages thereof, will be explained in the following with
reference to the accompanying drawings, in which like reference
characters designate the same or similar parts throughout the
figures and wherein:
[0021] FIG. 1 is an entire block diagram of a production apparatus
of a multilayer coating film of the present invention;
[0022] FIG. 2 is a block diagram of a coating device constructed as
a unit;
[0023] FIGS. 3(a), 3(b) and 3(c) are explanatory views explaining
switching of coaters;
[0024] FIG. 4 is an explanatory view explaining a dancer
roller;
[0025] FIG. 5 is a side sectional view explaining a dryer;
[0026] FIG. 6 is an explanatory view explaining relationship
between a nozzle plate and a backup roller of the dryer;
[0027] FIG. 7 is a sectional side view explaining a dust prevention
measure for a transfer path; and
[0028] FIG. 8 is a sectional front view explaining the dust
prevention measure for the transfer path.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] A preferred embodiment of a production apparatus of a
multilayer coating film according to the present invention will be
explained in detail below with reference to the attached
drawings.
[0030] FIG. 1 is a block diagram of an entire production apparatus
of a multilayer coating film according to the present invention and
is an example of the production apparatus which produces function
films such as a wide view angle film and an antireflection film.
The apparatus in FIG. 1 is constructed to produce a multilayer
coating film of five layers.
[0031] As shown in FIG. 1, the production apparatus 10 is entirely
housed in a production chamber 12, and clean conditioned air is
supplied into the production chamber 12 from an air conditioner
(not shown) through an air duct 13. A floor surface 14 of the
production chamber 12 is formed by a grating floor, and an
underfloor space 16 is formed under the floor surface 14.
Consequently, the conditioned air supplied into the production
chamber 12 flows down inside the production chamber 12 to the
underfloor space 16 from the floor surface 14 and is discharged
through an exhaust duct 18.
[0032] Inside the production chamber 12, a delivery device 22 for
letting out a web 20 wound like a roll, a dust removing device 24
which removes dust on the web 20 and is constructed as a unit, five
coating devices 26 which form coating layers on the web 20 in order
and are constructed as units, a heat treatment device 28 which
thermally treats the coating layers formed by coating on the web 20
and is constructed as a unit, a surface inspection device 30 which
checks whether there are a coating fault and a drying fault such as
level irregularity, streak, and unevenness induced by drying-wind
on a surface of the coating layers and is constructed as a unit,
and a winder 32 which rolls a product of the produced multilayer
coating film around on a core, are laterally placed in line from
the left end side to the right end side in FIG. 1. This constructs
a route of a series of function film production of: delivery of the
web 20.fwdarw.feeding into the first device.fwdarw.(dust
removal).fwdarw.(the first coating.fwdarw.drying.fwdarw.UV
treatment).fwdarw.intermediate feeding between the
devices.fwdarw.(the second coating.fwdarw.drying UV
treatment).fwdarw.intermediate feeding between the devices.fwdarw.
. . . .fwdarw.(the fifth coating.fwdarw.drying.fwdarw.UV
treatment).fwdarw.heat treatment.fwdarw.surface
inspection.fwdarw.feeding out of the device winding. In FIG. 1,
five of the coating devices 26 are shown, but the coating devices
26 as many as the number of layers of the multiple coating layers
to be formed are placed.
[0033] The dust removing device 24 is constructed by integrally
including at least a feed roller 36 for transferring the web 20
along a transfer path and a dust remover 38 provided at the
transfer path in a casing 34 having an inlet port and an outlet
port of the web 20. The dust remover 38 is not especially limited,
if only it can effectively remove dust from the web 20, and an air
dust removing method and an ultrasonic wave cleaner can be suitably
used. As the feed roller 36, a nip method of transferring the web
20 by nipping it with two rollers, or a suction method of
transferring the web 20 by sucking it to a roller can be suitably
used. The dust removing device 24 arrests dust of the web 20 at a
time just before the first coating is applied, and as to dust
prevention after the dust removing device 24, a static electricity
eliminator (not shown) is placed as necessary to prevent dust from
adhering to the web 20, or dust prevention is performed by cleaning
air blowing into the production chamber 12 and a transfer path case
98 (see FIGS. 7 and 8) covering the transfer path, which will be
described later.
[0034] As shown in FIGS. 1 and 2, the coating device 26 is
constructed by integrally including at least a feed roller 36 for
transferring the web 20 along the transfer path, a dancer roller 37
which is provided at the transfer path and eliminates a tension
variation of the web 20, a coater 40 which forms one coating layer
on the web 20, and a dryer 42 which dries the coating layer, in the
casing 34 having an inlet port 34a and an outlet port 34b of the
web 20. In this case, if a UV treatment device 43, which performs
UV (ultraviolet ray) treatment for the coating layer after drying,
is provided, the apparatus can correspond to the case in which a
cured resin contained in the coating solution is a UV cured resin
and the case in which it is a thermosetting resin as necessary.
[0035] The coater 40 is constructed to be switchable to any one of
a direct gravure coater, a reverse coater, a kiss coater, a
micro-gravure coater, a bar coater, and an extrusion coater so that
the kind of the coater 40 can be changed according to a coating
method and coating conditions of each layer of the multiple coating
layers, for example, the kind of a coating solution, coating
amount, tension of the web 20, drying temperature, air flow and so
on. Of the above coaters, as to three types of coaters which are
the direct gravure coater, the reverse coater, and the kiss coater,
pass rollers 44 placed at an upstream side and a downstream side of
the coater are made swingable in the A-B direction in FIG. 3(a)
around swing devices 46, and an impression roller 50 is constructed
to be movable in the C-D direction in FIG. 3(a) with a moving
device 52 so that an printing roller 48 rotatable forwardly and
reversely and the impression roller 50 can move close to or away
from each other as shown in FIG. 3(a). The swing devices 46 and the
moving device 52 are made to be operated with an operating panel
54. According to this structure, it is preferable to perform
switching of the direct gravure coater in FIG. 3(a), the kiss
coater in FIG. 3(b) and the reverse coater in FIG. 3(c) by
one-touch control on the operating panel 54. As for three types of
coaters which are the micro-gravure coater, the bar coater, and the
extrusion coater, it is preferable to unitize a set of coater
device and make it possible to attach and detach the entire device
to and from the casing 34.
[0036] Since coating of high quality with coating thickness
deviation being 3% or less without coating fault such as level
variations and streak is demanded in production of the function
film such as a wide view angle film and antireflection film, it is
preferable to construct the coating device 26 as follows.
[0037] In the case of the coater 40 using the printing roller 48
and the impression roller 50, the rotational speed variations of
the printing roller 48 and the impression roller 50 are made 0.2%
or less. For this purpose, it is preferable to use an AC vector
inverter motor, a planetary roller reducer, a form flexible joint,
and high precision bearing in a driving system. As the feed roller
36, a nip type and a suction type can be suitably used as the dust
removing device 24.
[0038] In the case of any kind of coater 40, it is preferable to
make the variation ratio of the transferring speed of the web 20 to
be 0.5% or less. For this purpose, it is preferable to adopt a
sectional drive method, and it is suitable to provide the feed
roller 36 at an end of a downstream of the transfer path of the web
20 at each coating device 26. Consequently, the feed rollers 36 are
individually driven to make it possible to transfer the web 20 to
the coating devices 26, and the tension in the transfer direction
of the web 20 is cut for each coating device 26, therefore making
it possible to prevent a tension variation occurring to one of the
coating device 26 from being consecutively transmitted to the other
coating devices 26. In the driving system for the feed rollers 36,
it is preferable to use an AC vector inverter motor, a planetary
roller reducer, a form flexible joint and a high precision
bearing.
[0039] Further, it is suitable to place the dancer roller 37 at an
upstream side of the coater 40. This not only makes it possible to
eliminate the transfer speed variation and the tension variation of
the web 20 in each of the coating devices 26, but also makes it
possible to prevent the transfer speed variation and the tension
variation of the web 20 in the coating device 26 at the upstream
side from influencing on the coating device 26 at the downstream
side. As the dancer roller 37, the one with the construction as
shown in FIG. 4 can be suitably used. In the dancer roller 37, a
swing plate 60, which swings in the E-F direction around a shaft
58, is placed under a plurality of pass rollers 56 fixedly placed,
and a plurality of moving rollers 62 are rotatably supported in a
longitudinal direction of the swing plate 60. The web 20 is
alternately passed around the pass rollers 56 and the moving
rollers 62. Consequently, if there is the transfer speed variation
and/or the tension variation in the web 20, the swing plate 60
swings in the E-F direction, and the variation is thereby
eliminated.
[0040] Harmony of the transfer speed and the tension of the web 20
between the plurality of coating devices 26 may be attained by
controlling the feed rollers 36 and the dancer rollers 37 as
follows. Namely, the feed roller 36 of the coating device 26 at the
uppermost stream position out of the plurality of coating devices
26 placed between the delivery device 22 and the winder 32 is made
a reference roller to control the transfer speed of the web 20, and
the feed rollers 36 of the second coating device 26 and the
following coating devices 36 are controlled with a speed signal
derived from the reference roller as the reference. The dancer
roller 37 of the coating device 26 at the uppermost stream position
out of the plurality of coating devices 26 is made as the reference
dancer roller, and the dancer rollers 37 of the second coating
device 26 and the following coating devices 26 are controlled with
a positional signal showing a swing amount of the reference dancer
roller 37 as the reference. In this case, as the dancer roller 37,
the large-capacity dancer roller 37 is preferable. This is to
control a long-period variation that has a large influence on the
coating fault, though ignoring a short-period variation of the
tension variation to some extent.
[0041] As shown in FIG. 5, in the dryer 42, a device casing 64 is
formed into an arch shape, and is divided into three dry zones 42A,
42B and 42C by partition plates 69 having passage ports 66 for the
web 20, and an air supply fan 68 for supplying dry air and an
exhaust fan 70 for exhausting air are provided at each of the dry
zones 42A, 42B and 42C. Each of an air supply duct 72 and an
exhaust duct 74, which are provided with the air supply fan 68 and
the exhaust fan 70, is provided with a damper device 76, and by
controlling the damper opening degree, supply and exhaust air
amounts in each of the dry zones 42A, 42B and 42C are individually
controlled. As a result, it is possible to control dry temperature
and relative humidity, and air quantity independently for each of
the dry zones 42A, 42B and 42C, and dry conditions corresponding to
the film surface strength of the coating layer formed on the web 20
can be set. Accordingly, the drying fault such as unevenness
induced by drying-wind on the coating surface during drying can be
prevented.
[0042] In the device casing 64, a number of backup rollers 78 are
arranged on an arch line along the transfer path of the web 20, and
an arch-shaped nozzle plate 80 is placed at an opposite side of the
backup rollers 78 across the web 20. An air supply chamber 82 is
formed in a space enclosed by the nozzle plate 80 and the device
casing 64, and an arch-shaped supply side current plate 84 which is
parallel with the nozzle plate 80 is placed in the air supply
chamber 82. Further, an air suction chamber 88 is formed in a space
enclosed by an arch-shaped suction plate 87 and the device casing
64 at an opposite side of the air supply chamber 82 across the
backup rollers 78, and an arch-shaped suction side current plate 90
is placed inside the air suction chamber 88. A number of holes are
formed in a punched metal form in the suction plate 87 and the
current plates 84 and 90, and dry air supplied into the device
casing 64 by the supply air fan 68 is formed into a laminar flow
from the air supply chamber 82 to the air suction chamber 88 by the
action of the current plates 84 and 90 at the supply side and the
suction side. As a result, disturbance of dry air at the coating
layer surface can be prevented, and therefore drying fault such as
unevenness induced by drying-wind can be further reduced.
[0043] As shown in FIG. 6, the nozzle plate 80 is formed into a
continuous corrugated plate form, which is parallel with the backup
rollers 78 (in a direction perpendicular to the sheet of FIG. 6)
and has alternating raised portions 80A and recessed portions 80B,
and nozzle holes 80C are provided in the raised portions 80A. As
known from FIG. 6, the backup rollers 78 and the raised portions
80A are constructed to be placed to face each other, so that dry
air, which is blown from the nozzle holes 80C, blows against the
backup rollers 78. As a result, the web 20 transferred on the
backup rollers 78 is pressed against the backup rollers 78 to be
gripped securely, and therefore flapping of the web 20 and
occurrence of a scratch on the web 20 by a slip can be
prevented.
[0044] Further, as shown in FIG. 5, micro-differential pressure
gauges 86 for managing static pressure differences are provided
between the respective adjacent dry zones 42A, 42B, and 42C, and
according to measurement values of the micro-differential pressure
gauges 86, air supply and exhaust amount is managed so that the
static pressure of each of the dry zones 42A, 42B and 42C becomes
the same. Consequently, air of the adjacent dry zones 42A, 42B and
42C does not go back and forth via the passage ports 66 for the web
20, which are formed at the partition plates 69, and therefore
drying condition for each of the dry zones 42A, 42B and 42C can be
set with high precision.
[0045] The heat treatment device 28 is constructed by integrally
incorporating at least a heat treatment machine 51 for thermally
treating the coating layer inside the casing 34 having an inlet
port and an outlet port for the web 20 as shown in FIG. 1. As the
heat treatment machine 51, for example, a machine with a method of
heating the web 20 to be transferred by supplying hot air into the
casing 34 can be suitably used as shown in FIG. 1, but the heat
treatment machine 51 is not limited to this. In FIG. 1, the feed
roller 36 is not provided in the heat treatment device 28, but it
may be provided therein.
[0046] The surface inspection device 30 is constructed by
integrally incorporating at least the feed roller 36 for
transferring the web 20 along the transfer path, and a surface
inspection machine 55, which is provided at the transfer path and
inspects the state of the coating surface of the coating layer,
inside the casing 34 having an inlet port and an outlet port for
the web 20 as shown in FIG. 1. Since the surface inspection device
30 is constructed as the device having an independent function, an
optional number of them can be placed at an optional position of
the production apparatus 10, and by placing it in front of the
winder 32 as shown in FIG. 1 and carrying out the following usage,
the surface inspection of each layer of the multiple coating layers
can be performed with one surface inspection device 30. Namely, at
the time of starting operation of the production apparatus 10, or
when a defect in coating and the like is found in an end product,
coating and surface inspection are performed for each layer from
the coater 40 at the upstream side, then if this is acceptable,
coating and surface inspection are performed for the following
coaters 40 in order, and the final coating and surface inspection
are performed. As a result, it can be determined which layer has
the coating defect. During normal operations, the surface
inspection device 30 is used for surface inspection of the end
products.
[0047] Next, a dust prevention measure on the transfer path of the
above-described devices 24 to 30 is explained with the example of
the coating device 26 in FIG. 2.
[0048] As shown in FIG. 2, air inlets 92 are formed in a ceiling
surface of the casing 34, and a plurality of fan filter units 96
are provided in a space 94 in the ceiling (see FIG. 1) of the
casing 34, which corresponds to the air inlets 92. The conditioned
air is supplied to the space 94 in the ceiling from the air
conditioner (not shown). The fan filter unit 96 is a unit in which
a fan 96A and a HEPA filter 96B are integrally incorporated, and
the number of the fan filter units 96 provided can be easily
increased or decreased according to cleanliness demanded according
to the kind of the unit. Meanwhile, an air exhaust port 97 is
formed in the bottom surface of the casing 34, and the casing 34 is
placed on the floor surface 14 formed by the grating floor, whereby
the casing 34 is allowed to communicate with the underfloor space
16 (see FIG. 1). As a result, the conditioned air which is supplied
to the space 94 in the ceiling is further purified in the HEPA
filter 96B and blown into the casing 34, flows down inside the
casing 34, then flows into the underfloor space 16 from the floor
surface 14, and is exhausted through the exhaust duct 18.
[0049] The transfer path from the inlet port 34a to the outlet port
34b of the casing 34 is enclosed by a box-shaped or tube-shaped
transfer path case 98 along the transfer path. An air introduction
port 100 and air exhaust ports 102 are formed at the transfer path
case 98, and the air introduction port 100 is connected to one of
the fan filter units 96. The parts enclosed by the transfer path
case 98 are an area around the dancer roller 37, an area around the
coater 40, an area around the UV treatment machine 43, and an area
around a passage 104 from the UV treatment machine 43 to the outlet
port 34b.
[0050] FIGS. 7 and 8 show the passage 104 part from the UV
treatment machine 43 to the outlet port 34b in detail, wherein a
number of pass rollers 106 which transfer the web 20 are arranged
in a vertical direction, and the tube-shaped transfer path case 98
is provided along this passage 104. As a result, as known from FIG.
8, the passage 104 is formed to be a doubly enclosed structure by
the casing 34 and the transfer path case 98. As shown in FIG. 8,
the relationship between the casing 34 and the transfer path case
98, and a pass roller 106 is constructed so that roller journal
portions 110 supported by bearings 108 fixed to the inner wall
surface of the casing 34 are placed outside the transfer path case
98, and only a roller shell portion 112 of the pass roller 106 and
the web 20 are enclosed by the transfer path case 98. In this
manner, out of the pass roller 106, only the roller shell portion
112 with which the web 20 is in contact is enclosed by the transfer
path case 98, whereby the transfer path case 98 can be made slim
and small in volumetric capacity corresponding to the passage 104,
and therefore a wind speed of clean air supplied into the transfer
path case 98 can be maintained and dead zone where clean air does
not flow can be prevented from occurring. The bearings 108 and the
roller journal parts 110 where dust easily occurs and dust easily
settles are located outside the transfer path case 98, whereby
cleanliness inside the transfer path case 98 can be kept further
higher. In such construction, gaps 114 not to hinder rotation are
formed between the transfer path case 98 and the roller journal
parts 110. However, a flow of air from an inside of the transfer
path case 98 to an outside thereof always occurs through the gaps
114, and therefore dust which occurs at the bearings 108 and the
roller journal parts 110 do not enter the transfer path case 98.
Further, as shown in FIG. 8, a plurality of micro-differential
pressure gauges 116 for detecting pressure difference between the
inside and the outside of the transfer path case 98 are provided
inside and outside the transfer path case 98, and according to the
detection result of the micro-differential pressure gauge 116, the
inside pressure of the transfer path case 98 is kept higher than
the outside pressure, whereby it is made further possible that air
in the casing 34 side does not enter the transfer path case 98.
Further, it is more preferable to provide a micro-differential
gauge 118 for detecting the pressure difference between an inside
and an outside of the casing 34 to keep the inside pressure of the
casing 34 higher than the outside pressure.
[0051] The above-described dust prevention measure of the transfer
path is the explanation of the transfer path of the passage 104
part from the UV treatment machine 43 to the outlet port 34b, and
it is suitable to construct the dancer roller 37, the coater 40 and
the UV treatment machine 43 so that the drive parts where dust
easily occurs are placed outside the transfer path case 98 and
perform pressure management with the micro-differential pressure
gauges 116 and 118.
[0052] As explained thus far, according to the production apparatus
of the multilayer coating film of the present invention, coating
construction with flexibility according to the number of layers of
the multiple coating layers can be easily constructed, and the
multilayer coating film with small film thickness, without dust
attaching to the film surface, dry fault such as unevenness induced
by drying-wind on the film surface and coating fault such as level
variation and a streak, and further with coating surface state with
high quality with coating thickness deviation of 3% or less can be
produced. Accordingly, the present invention is preferable to
produce various kinds of function films such as wide view angle
films and antireflection films.
[0053] It should be understood, however, that there is no intention
to limit the invention to the specific forms disclosed, but on the
contrary, the invention is to cover all modifications, alternate
constructions and equivalents falling within the spirit and scope
of the invention as expressed in the appended claims.
* * * * *