U.S. patent application number 10/254884 was filed with the patent office on 2003-06-05 for coating film, and method and apparatus for producing the same.
This patent application is currently assigned to Matsushita Electric Industrial Co., Ltd.. Invention is credited to Ebisawa, Mitsuo, Mino, Norihisa, Ogawa, Kazufumi, Oono, Yoshiaki.
Application Number | 20030104129 10/254884 |
Document ID | / |
Family ID | 17117005 |
Filed Date | 2003-06-05 |
United States Patent
Application |
20030104129 |
Kind Code |
A1 |
Mino, Norihisa ; et
al. |
June 5, 2003 |
Coating film, and method and apparatus for producing the same
Abstract
A compound represented by a general formula (1) ABXn (where A is
a carbon-containing group; B is at least one element selected from
Si, Ge, Sn, Ti and Zr; X is a hydrolyzable group; and n is 1, 2 or
3), for example, a chlorosilane compound having a fluorocarbon
group, is measured in an amount required for one time application,
and dropped from a nozzle on a surface of a substrate having an
active hydrogen on the surface, and simultaneously it is rubbed
with a coater made of a sponge or a nonwoven fabric, etc.
Furthermore, it is rubbed with a coater made of a sponge or a
nonwoven fabric, etc. while blowing a dry warm air, and an
elimination reaction is caused between the active hydrogen on the
surface of the substrate and the hydrolyzable group of the
compound. Thus, the compound is covalently bonded to the substrate.
The molecules of the is silane compound also are polymerized with
one another to be fixed. Thus can be provided a coating film and a
method and an apparatus for producing the same, in which: an amount
of a liquid required for forming a film is decreased even when the
substrate has an irregular shape and a large size; it is not
necessary to be concerned for the pot life of a coating solution;
the substrate is manipulated easily; and cost is low.
Inventors: |
Mino, Norihisa; (Nara-shi,
JP) ; Ebisawa, Mitsuo; (Kyoto, JP) ; Oono,
Yoshiaki; (Nabari-shi, JP) ; Ogawa, Kazufumi;
(Nara, JP) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Matsushita Electric Industrial Co.,
Ltd.
Kadoma-shi
JP
|
Family ID: |
17117005 |
Appl. No.: |
10/254884 |
Filed: |
September 24, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10254884 |
Sep 24, 2002 |
|
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|
09636225 |
Aug 10, 2000 |
|
|
|
6485785 |
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Current U.S.
Class: |
427/346 ;
427/355 |
Current CPC
Class: |
B05C 9/14 20130101; B05C
1/02 20130101; C04B 41/009 20130101; B82Y 40/00 20130101; B05D
3/0486 20130101; C03C 17/30 20130101; B82Y 30/00 20130101; C03C
17/28 20130101; B05C 1/06 20130101; B05D 1/185 20130101; B05D 5/08
20130101; C04B 41/84 20130101; C04B 41/4933 20130101; C04B 41/009
20130101; C04B 35/10 20130101 |
Class at
Publication: |
427/346 ;
427/355 |
International
Class: |
B05D 003/12 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 1999 |
JP |
11-244322 |
Claims
What is claimed is:
1. A method for producing a coating film using a compound (1)
represented by a general formula (1) ABXn (where A is a
carbon-containing group; B is at least one element selected from
Si, Ge, Sn, Ti and Zr; X is a hydrolyzable group; and n is 1, 2 or
3) as a raw material, comprising: measuring the compound (1) in an
amount required for one time application on a surface of a
substrate having an active hydrogen on the surface, and supplying
it to the surface of the substrate at each time of application; in
an atmosphere having a water vapor concentration of more than
0.0076 kg/M.sup.3, bringing the compound (1) into contact with the
surface of the substrate, causing an elimination reaction between
the active hydrogen on the surface of the substrate and the
hydrolyzable group in parts of the molecules of the compound (1),
thereby covalently bonding the parts of the molecules of the
compound (1) to the surface of the substrate, as well as
polymerizing parts of the molecules of the compound (1) with one
another using water molecules present in the atmosphere.
2. The method according to claim 1, wherein at least one solvent
not having an active hydrogen is further added to the compound
(1).
3. The method according to claim 1, further comprising washing the
substrate and the coating film formed on the substrate after the
steps shown in claim 1.
4. The method according to claim 1, wherein A in the formula (1) is
at least one organic group selected from hydrocarbon groups,
fluorocarbon groups, and fluorocarbon-hydrocarbon groups.
5. The method according to claim 1, wherein X in the formula (1) is
at least one selected from an isocyanate group, an alkoxyl group,
and halogen atoms.
6. The method according to claim 1, wherein the group having an
active hydrogen formed on the surface of the substrate is at least
one selected from --OH, --NH.sub.2, >NH and --COOH groups.
7. The method according to claim 1, wherein the chemical reaction
is an isocyanic acid elimination reaction, an alcohol elimination
reaction, or a halogenohydrogen elimination reaction.
8. The method according to claim 1, wherein the formed coating film
has a thickness of at least 1 nm but not more than 0.5 .mu.m.
9. The method according to claim 1, wherein the substrate is at
least one selected from glass, metals, metal oxides, ceramics,
polymer compounds, and composites thereof.
10. The method according to claim 1, wherein the substrate is a
product made from an inorganic oxide as a raw material, and is at
least one selected from glass products including glass sheets and
mirrors, ceramic products, enameled products, and composites
thereof.
11. The method according to claim 1, wherein the water vapor
concentration is in a range of 0.077 to 0.0168 kg/m.sup.3.
12. The method according to claim 1, wherein the compound (1) is
brought into contact with the surface of the substrate by
impregnating a porous material with the compound (1) and bringing
it into contact with the surface of the substrate, and wherein the
porous material is at least one selected from resin foams, woven
fabrics, knitted fabrics, nonwoven fabrics, and fiber
aggregates.
13. The method according to claim 1, wherein means for bringing the
compound (1) into contact with the surface of the substrate is
rubbing a body impregnated with the compound (1) on the surface of
the substrate, while supplying a solution containing the compound
(1) on the surface of the substrate.
14. The method according to claim 1, wherein after bringing the
compound (1) into contact with the surface of the substrate, a body
impregnated with the compound (1) is rubbed on the surface of the
substrate, while blowing a dry warm air to the surface of the
substrate.
15. A method for producing a coating film, comprising: applying a
coating solution containing a silane-based compound having at least
one reactive group selected from at least halogen atoms, an alkoxyl
group, and an isocyanate group, to a surface of a substrate having
an active hydrogen on the surface; causing an elimination reaction
between the active hydrogen on the surface of the substrate and the
reactive group of the silane-based compound, thereby covalently
bonding the silane-based compound to the surface of the substrate,
wherein the method comprises: conveying the substrate into a
chamber in which a water vapor concentration in an atmosphere is
maintained at more than 0.0076 kg/m.sup.3; measuring a coating
solution containing the silane-based compound and at least one
solvent not having an active hydrogen in an amount required for one
time application (a required amount), and supplying it to a coating
device present in the chamber at each time of application;
spreading and rubbing the coating solution uniformly on the surface
of the substrate with the coating device; then changing the
atmosphere in the chamber and increasing a concentration of the
silane-based compound, thereby accelerating an elimination reaction
between the reactive group in parts of the molecules of the
silane-based compound and the active hydrogen on the surface of the
substrate, and thereby covalently bonding the silane-based compound
to the surface of the substrate; then removing the solvent, and
wherein polymerizing parts of the molecules of the silane-based
compound with one another using water molecules present in the
atmosphere also occurs.
16. The method according to claim 15, wherein when accelerating the
elimination reaction, the coating device is operated so that a
liquid containing the silane-based compound is further brought into
contact with the surface of the substrate.
17. The method according to claim 15, wherein when changing the
atmosphere in the chamber and increasing the concentration of the
silane-based compound, at least one treatment selected from
changing a temperature in the chamber, changing a gas flow rate in
the chamber, and changing a temperature of the substrate, is
carried out.
18. The method according to claim 15, wherein the solvent not
having an active hydrogen is at least one selected from hydrocarbon
compounds, siloxane-based compounds, and halogenated
hydrocarbons.
19. The method according to claim 15, wherein the coating device
comprises a body in a form that makes it impregnated with the
coating solution.
20. The method according to claim 19, wherein the body of the
coating device in a form that makes it impregnated with the coating
solution is a porous material, and wherein the porous material is
at least one selected from resin foams, woven fabrics, knitted
fabrics, nonwoven fabrics, and fiber aggregates.
21. The method according to claim 15, wherein when spreading the
coating solution uniformly on the surface of the substrate using
the coating device, the substrate is fixed, and the coating device
is rotated or moved in at least one direction selected from a
longitudinal direction and a transverse direction.
22. The method according to claim 15, wherein the process of
spreading the coating solution uniformly on the surface of the
substrate and the process of accelerating the elimination reaction
between the reactive group of the silane-based compound in an
amount required for one time application and the active hydrogen on
the surface of the substrate are carried out in two independent
chambers.
23. The method according to claim 15, wherein means for bringing
the silane-based compound into contact with the surface of the
substrate is rubbing a body impregnated with the silane-based
compound on the surface of the substrate, while supplying a
solution containing the silane-based compound to the surface of the
substrate.
24. The method according to claim 15, wherein after bringing the
silane-based compound into contact with the surface of the
substrate, a body impregnated with the silane-based compound is
rubbed on the surface of the substrate, while blowing a dry warm
air to the surface of the substrate.
25. An apparatus for producing a coating film, comprising: a device
for transporting a substrate from an inlet to an outlet in a
chamber, a device for measuring a coating solution containing a
silane-based compound and at least one solvent not having an active
hydrogen in an amount required for one time application, and
supplying it to a coating device present in the chamber at each
time of application; a coating device for applying and spreading
the coating solution uniformly, and for accelerating an elimination
reaction between the reactive group of the silane-based compound in
an amount required for one time application and the active hydrogen
on the surface of the substrate; a device for controlling and
maintaining a water vapor concentration in an atmosphere in the
chamber at more than 0.0076 kg/m.sup.3; and a device for removing
the solvent in the coating solution.
26. The apparatus according to claim 25, wherein the device for
transporting the substrate in the chamber is of a belting system or
a roller system.
27. The apparatus according to claim 25, wherein the device for
supplying the coating solution containing the silane-based compound
and the solvent on the surface of the substrate is of a nozzle
system or a spray system.
28. The apparatus according to claim 25, wherein the coating device
comprises a body in a form that makes it impregnated with the
coating solution.
29. The apparatus according to claim 25, wherein the body of the
coating device in a form that makes it impregnated with the coating
solution is a porous material, and wherein the porous material is
at least one selected from resin foams, woven fabrics, knitted
fabrics, nonwoven fabrics, and fiber aggregates.
30. The apparatus according to claim 25, wherein the coating device
is rotated or moved in a longitudinal direction and/or a transverse
direction.
31. The apparatus according to claim 25, wherein a coating device
for spreading the coating solution uniformly on the surface of the
substrate is different from a coating device for increasing the
concentration of the silane-based compound and accelerating the
elimination reaction between the reactive group of the silane-based
compound at least in an amount required for one time application
and the active hydrogen on the surface of the substrate.
32. The apparatus according to claim 25, wherein a chamber in which
the coating solution is spread uniformly on the surface of the
substrate and a chamber in which the elimination reaction between
the reactive group of the silane-based compound in an amount
required for one time application and the active hydrogen on the
surface of the substrate is accelerated are two independent
chambers.
33. The apparatus according to claim 25, wherein the device for
bringing the silane-based compound into contact with the surface of
the substrate rubs a body impregnated with the silane-based
compound on the surface of the substrate, while supplying a
solution containing the silane-based compound to the surface of the
substrate.
34. The apparatus according to claim 25, wherein after bringing the
silane-based compound into contact with the surface of the
substrate, a body impregnated with the silane-based compound is
rubbed on the surface of the substrate, while blowing a dry warm
air to the surface of the substrate.
35. A coating film characterized in that: the film is transparent;
the film has a thickness of 1 nm to 0.5 .mu.m; the film has a
durability of at least five times for an abrasion resistance test
in which a mixture of sugar and soy source (1:1 by weight ratio) is
applied, heated at a high temperature of 300.degree. C. for 20
minutes, and cooled, then a fouling baked and adhered can be
removed by rubbing with a wet cloth by hand; parts of the molecules
of the film are covalently bonded to a surface of a substrate via
at least one element selected from Si, Ge, Sn, Ti and Zr; and parts
of the molecules of the film are polymerized with one another.
36. The coating film according to claim 35, wherein the substrate
is at least one selected from glass, metals, metal oxides,
ceramics, resins, porcelains, enamel, and composites thereof.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a coating film (hereinafter
also referred to as "an organic thin film"), and a method and an
apparatus for producing the same, in which a compound having a
hydrolyzable group, e.g. a silane-based compound, is chemically
bonded to a surface of a substrate.
BACKGROUND OF THE INVENTION
[0002] Traditionally, methods of forming organic thin films have
been developed. Typical examples of conventional technologies for
forming organic thin films are bar coating, dipping, etc. According
to these methods, a film having a thickness on the order of at
least tens of micrometer is formed. Furthermore, these methods
control the thickness of the film on the order of about micrometer,
and are not suitable for controlling the film thickness on the
order of nanometer. Spin coating is an example of a more
controllable method than these methods, and is often used to form
devices having a minute structure such as semiconductors. According
to this method, formation of a film having a thickness of about one
to several micrometers can be realized, and also the thickness of
the film can be controlled easily. However, because the organic
thin film produced by this method is not bonded integrally to a
substrate, the film may peel off easily. In the manufacture of
semiconductor devices, such an ease of peeling is required, and
this method is utilized.
[0003] On the other hand, it already has been proposed to form a
molecular film by applying a chlorosilane-based compound, which has
a chlorosilyl group at an end of a molecule containing an alkyl
group or a fluoroalkyl group, to a surface of glass or the like
having an active hydrogen on the surface, and covalently bonding it
to the surface by a hydrogen chloride elimination reaction.
[0004] As conventional technologies, there are methods in which a
substrate is immersed in a coating solution containing a
chlorosilane-based compound (JP 1-70917A, EP 0492545A). In another
example, a method in which a chlorosilane-based compound as a gas
is brought into contact with a surface of a substrate and reacted
has been proposed. Also, when using an alkoxysilane-based compound,
a method in which an aqueous solution thereof is prepared and
hydrolyzed to form a coating film has been proposed (Research
Report of Tokyo Metropolitan Industrial Center, No. 22, pages 57-60
(1993)). Furthermore, a more specific example is a method in which
a molecular film is formed by roll coating (JP 10-180179 A).
[0005] The conventional immersion method is excellent when the
shape of the object to be coated is not flat but is irregular. In
this case, a film can be formed on the irregular surface, as a
liquid reacts along the surface. However, in the immersion method,
a large amount of liquid is required for immersion, and
manipulations for removing and inserting a substrate are necessary.
Thus, the operation becomes complex and requires a large amount of
time, resulting in a high cost. Furthermore, because a
chlorosilane-based compound reacts with water easily, its short pot
life is a problem. Moreover, in the immersion method, because the
chlorosilane-based compound is brought into contact with the entire
substrate and reacted, the method is inconvenient when the
substrate has a surface which is not desirable to be coated with
the chlorosilane-based compound.
[0006] Furthermore, in the method in which a chlorosilane-based
compound as a gas is brought into contact with a surface of a
substrate and reacted, it is difficult to form a uniform molecular
film. The same problem also occurs when using an alkoxysilane-based
compound or an isocyanate silane-based compound. Furthermore, when
using an aqueous solution of an alkoxysilane-based compound, film
thickness is increased, and irregularity in film thickness is
generated easily. The same applies to the case when using an
isocyanate silane-based compound.
[0007] More specifically, the method in which a film is formed by
roll coating has solved conventional problems in the immersion
method, such as amount of liquid, complex operation, long
operational time, dealing with a surface not needed to be coated,
etc. However, it has a problem in that the object to be coated must
be a flat plate. Moreover, there has not been any method in which
an organic thin film having a thickness on the order of not more
than submicrometer is produced at a low cost.
DISCLOSURE OF THE INVENTION
[0008] In order to solve the above-mentioned conventional problems,
it is an object of the present invention to provide a coating film
and a method and an apparatus for producing the same, in which an
amount of a liquid required for forming a film is decreased even
when an object (substrate) to be coated with the film is not a flat
plate but has an irregular shape and a large size; it is not
necessary to be concerned over the pot life of a coating solution;
the substrate is manipulated easily; and cost is low.
[0009] In order to accomplish the above-mentioned object, the
present invention provides a first method for producing a coating
film using a compound (1) represented by a general formula (1) ABXn
(where A is a carbon-containing group; B is at least one element
selected from Si, Ge, Sn, Ti and Zr; X is a hydrolyzable group; and
n is 1, 2 or 3) as a raw material, comprising: measuring the
compound (1) in an amount required for one time application (a
required amount) on a surface of a substrate having an active
hydrogen on the surface, and supplying it to the surface of the
substrate-at each time of application; in an atmosphere having a
water vapor concentration of more than 0.0076 kg/m.sup.3, bringing
the compound (1) into contact with the surface of the substrate,
causing an elimination reaction between the active hydrogen on the
surface of the substrate and the hydrolyzable group in parts of the
molecules of the compound (1), thereby covalently bonding the parts
of the molecules of the compound (1) to the surface of the
substrate, as well as polymerizing parts of the molecules of the
compound (1) with one another using water molecules present in the
atmosphere.
[0010] Next, the present invention provides a second method for
producing a coating film, comprising: applying a coating solution
containing a silane-based compound having at least one reactive
group selected from at least halogen atoms, an alkoxyl group and an
isocyanate group to a surface of a substrate having an active
hydrogen on the surface; causing an elimination reaction between
the active hydrogen on the surface of the substrate and the
reactive group of the silane-based compound, thereby covalently
bonding the silane-based compound to the surface of the substrate,
wherein the method comprises: conveying the substrate into a
chamber in which a water vapor concentration in an atmosphere is
maintained at more than 0.0076 kg/m.sup.3; measuring a coating
solution containing the silane-based compound and at least one
solvent not having an active hydrogen in an amount required for one
time application (a required amount), and supplying it to a coating
device present in the chamber at each time of application;
spreading and rubbing the coating solution uniformly on the surface
of the substrate with the coating device; then changing the
atmosphere in the chamber and increasing a concentration of the
silane-based compound, thereby accelerating an elimination reaction
between the reactive group in parts of the molecules of the
silane-based compound and the active hydrogen on the surface of the
substrate, thereby covalently bonding the silane-based compound to
the surface of the substrate; then removing the solvent, as well as
polymerizing parts of the molecules of the silane-based compound
with one another using water molecules present in the
atmosphere.
[0011] Next, an apparatus for producing a coating film of the
present invention comprises: a device for transporting a substrate
from an inlet to an outlet in a chamber; a device for measuring a
coating solution containing a silane-based compound and at least
one solvent not having an active hydrogen in an amount required for
one time application (a required amount) and supplying it to a
coating device present in the chamber at each time of application;
a coating device for applying and spreading the coating solution
uniformly, and for accelerating an elimination reaction between the
reactive group of the silane-based compound in an amount required
for one time application and the active hydrogen on the surface of
the substrate; a device for controlling and maintaining a water
vapor concentration in an atmosphere in the chamber; and a device
for removing the solvent in the coating solution.
[0012] Next, a coating film of the present invention is
characterized in that: the film is transparent; the film has a
thickness of 1 nm to 0.5 .mu.m; the film has a durability of at
least five times for an abrasion resistance test in which a mixture
of sugar and soy source (1:1 by weight ratio) is applied, heated at
a high temperature of 300.degree. C. for 20 minutes, and cooled,
then a fouling baked and adhered to the film can be removed by
rubbing with a wet cloth by one's hand; parts of the molecules of
the film are covalently bonded to a surface of a substrate via at
least one element selected from Si, Ge, Sn, Ti and Zr; and parts of
the molecules of the film are polymerized with one another.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic diagram of a rotational coating
film-forming apparatus according to Example 4 of the present
invention.
[0014] FIG. 2 is a perspective view showing a coating method
according to Example 4 of the present invention.
[0015] FIG. 3 is a perspective view showing a coating method
according to Example 4 of the present invention.
[0016] FIG. 4 is a schematic diagram of a cross section of a
substrate and a coating film formed on the substrate according to
Example 4 of the present invention.
[0017] FIG. 5 is a schematic diagram of a coating device according
to Example 5 of the present invention.
[0018] FIG. 6 is a schematic diagram of a coating device according
to Example 5 of the present invention.
[0019] FIG. 7 is a perspective view showing a coating method
according to Example 6 of the present invention.
[0020] FIG. 8 is a perspective view showing a coating method
according to Example 7 of the present invention.
[0021] FIG. 9 is a perspective view showing a coating method
according to Example 8 of the present invention.
[0022] FIG. 10 is a perspective view showing a coating method
according to Example 9 of the present invention.
[0023] FIG. 11 is a perspective view showing a coating method
according to Example 10 of the present invention.
[0024] FIG. 12 is a flow diagram showing a mechanism of a repair
system for ceramic and glass products according to Example 11 of
the present invention.
[0025] FIG. 13 is a schematic diagram of a product-repair system
according to Example 11 of the present invention.
[0026] FIG. 14 is a diagram showing a mechanism of film repairing
according to Example 11 of the present invention.
[0027] FIG. 15 is a diagram showing a vehicle loaded with a
film-repairing apparatus according to Example 11 of the present
invention.
[0028] FIG. 16 is a diagram showing the film-repairing apparatus in
the vehicle according to Example 11 of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] In the present invention, when using a chlorosilane compound
as the silane-based compound, a hydrogen chloride elimination
reaction occurs as the elimination reaction. When using an
alkoxysilane compound, an alcohol elimination reaction occurs as
the elimination reaction. And when using an isocyanate compound, an
isocyanic acid elimination reaction occurs as the elimination
reaction.
[0030] Furthermore, in the above-mentioned method, it is preferable
that the silane-based compound contains an alkyl group or a
fluoroalkyl group. Particularly, when containing a fluoroalkyl
group, it has improved water repellency, oil repellency, and
anti-fouling property, etc., and thus it is preferable.
[0031] Furthermore, in the above-mentioned method, it is preferable
that the coating device is operated so that a liquid containing the
silane-based compound is further brought into contact with the
surface of the substrate in the step of increasing the
concentration of the silane-based compound and accelerating an
elimination reaction between the reactive group of the silane-based
compound at least in an amount required for one time application
and the active hydrogen on the surface of the substrate.
Accordingly, the elimination reaction can be ensured better, and a
final organic thin film of a high density can be formed.
[0032] Furthermore, in the above-mentioned method, it is preferable
that the solvent is removed either by changing the atmosphere in
the chamber or by operating the coating device, or by both.
Accordingly, the concentration of the coating solution can be
increased, so that probability of occurrence of the elimination
reaction may be increased further.
[0033] Furthermore, in the above-mentioned method, it is preferable
that the atmosphere in the chamber is changed by changing the
temperature in the chamber, changing the gas flow rate in the
chamber, or changing the temperature of the substrate, or by a
combination of these measures.
[0034] Furthermore, in the above-mentioned method, it is preferable
that the solvent not having an active hydrogen is at least one
selected from hydrocarbon compounds, siloxane based compounds, and
halogenated hydrocarbons. If the solvent has an active hydrogen, it
will react with the silane-based compound.
[0035] Furthermore, in the above-mentioned method, it is preferable
that the coating device comprises a body in a form that makes it
impregnated with the coating solution. Thus, the coating device can
absorb excess of the coating solution, so that the coating solution
can be applied in a required minimum amount to the surface of the
substrate. Furthermore, it is preferable that the body of the
coating device in a form that makes it impregnated with the coating
solution is a porous material, such as a resin foam, a woven
fabric, or a nonwoven fabric. Particularly, by using a flexible
material, substrates of various forms can be handled.
[0036] Furthermore, in the above-mentioned method, it is preferable
that the step of spreading the coating solution uniformly on the
surface of the substrate is carried out by fixing the substrate,
and rotating the coating device or moving it in longitudinal and
transverse directions, or conducting both simultaneously. Thus,
substrates of various forms can be handled with flexibility.
[0037] Furthermore, in the above-mentioned method, it is preferable
that the coating device for spreading the coating solution
uniformly on the surface of the substrate is different from the
coating device for increasing the concentration of the silane-based
compound and accelerating the elimination reaction between the
reactive group of the silane-based compound at least in an amount
required for one time application and the active hydrogen on the
surface of the substrate. Accordingly, production efficiency can be
doubled.
[0038] Furthermore, in the above-mentioned method, it is preferable
that the step of spreading the coating solution uniformly on the
surface of the substrate and the step of accelerating the
elimination reaction between the reactive group of the silane-based
compound in an amount required for one time application and the
active hydrogen on the surface of the substrate are carried out in
two independent chambers. The atmospheres in the chambers in these
two steps are different, so that productivity of an organic thin
film can be increased significantly by providing two chambers with
different atmospheres, rather than changing the atmosphere in the
chamber in each step.
[0039] Next, the apparatus of the present invention includes a
device for transporting a substrate from an inlet to an outlet in a
chamber; a device for dropping a coating solution containing a
silane-based compound and a solvent on a surface of the substrate;
a coating device for applying and spreading the coating solution
uniformly, in which an elimination reaction between a reactive
group of the silane-based compound in an amount required for one
time application and an active hydrogen on the surface of the
substrate is accelerated; a device for controlling and maintaining
a water vapor concentration in an atmosphere in the chamber; and a
device for removing the solvent in the coating solution.
[0040] In the above-mentioned apparatus, it is preferable that the
device for transporting the substrate in the chamber is of a
belting system or a roller system.
[0041] Furthermore, in the above-mentioned apparatus, it is
preferable that the device for dropping the coating solution
containing a silane-based compound and a solvent on a surface of
the substrate is of a nozzle system or a spray system.
[0042] Furthermore, in the above-mentioned apparatus, it is
preferable that the device for controlling and maintaining the
water vapor concentration in the atmosphere controls and maintains
it in the range of more than 0.0076 kg/m.sup.3.
[0043] Furthermore, in the above-mentioned apparatus, it is
preferable that the coating device comprises a body in a form that
makes it impregnated with the coating solution.
[0044] Furthermore, in the above-mentioned apparatus, it is
preferable that the body in a form that makes it impregnated with
the coating solution of the coating device is a porous material,
such as a resin foam, a woven fabric, or a nonwoven fabric.
[0045] Furthermore, in the above-mentioned apparatus, it is
preferable that the coating device is rotated or moved in the
longitudinal and transverse directions, or both rotated and moved
simultaneously.
[0046] Furthermore, in the above-mentioned apparatus, it is
preferable that the coating device for spreading the coating
solution uniformly on the surface of the substrate is different
from the coating device for increasing the concentration of the
silane-based compound and accelerating the elimination reaction
between the reactive group of the silane-based compound at least in
an amount required for one time application and the active hydrogen
on the surface of the substrate.
[0047] Furthermore, in the above-mentioned apparatus, it is
preferable that the chamber in which the coating solution is spread
uniformly on the surface of the substrate, and the chamber in which
the elimination reaction between the reactive group of the
silane-based compound in an amount required for one time
application and the active hydrogen on the surface of the substrate
is accelerated, are two independent chambers.
[0048] Furthermore, in the above-mentioned apparatus, it is
preferable that the device for removing the solvent in the coating
solution from the surface of the substrate is of at least one
selected from gas blowing, heating evaporation, and evaporation
under reduced pressure.
[0049] In the above, it is preferable that at least the surface of
the portion of the substrate on which the organic thin film is to
be formed is covered with a material comprising glass, a metal, a
plastic, or a metal oxide.
[0050] In the above, it is preferable that a group having an active
hydrogen is exposed on a surface of the plastic.
[0051] In the above, it is preferable that the group having an
active hydrogen is exposed on a surface of the plastic by oxygen
plasma treatment, corona discharge treatment, ozone oxidation
treatment, or ultraviolet oxidation treatment.
[0052] In the above, it is preferable that the substrate is at
least one selected from glass, metals, metal oxides, ceramics,
polymer compounds, and composites thereof.
[0053] In the above, it is preferable that the substrate is a
product made from an inorganic oxide as a raw material, and is at
least one selected from glass products including glass sheets and
mirrors, ceramic products, enameled products, and composites
thereof In the present invention, a siloxane bond may be formed
between the substrate and the silane-based compound, and a coating
film having a thickness of at least 1 nm but not more than 1 .mu.m
may be formed on the substrate.
[0054] In the present invention, it is preferable that the
silane-based compound contains an alkyl group or a fluoroalkyl
group. Specifically, as a compound having a fluoroalkyl group,
fluoroalkylsilane compounds represented by a general formula
C.sub.nF.sub.2n+1(CH.sub.2).sub.2SiCl.su- b.3 (n is a positive
integer of 1 to 30) such as heptadecafluoro-1,1,2,2-t-
etrahydrodecyltrichlorosilane are available.
[0055] Furthermore, as the solvent in which the chlorosilane-based
compound is dissolved, solvents not having an active hydrogen that
is reactive with the chlorosilane-based compound may be used. For
example, with respect to the above-mentioned fluoroalkylsilane
compound, hydrocarbon based solvents, halogenated hydrocarbon based
solvents, alkylsiloxane based solvents, silicone oil solvents, and
the like may be used. As specific examples of these respective
solvents, hydrocarbon based solvents include petroleum solvents
represented by a general formula C.sub.nH.sub.2n+2 (where n is a
positive integer) or C.sub.nH.sub.2n such as terpene oil.
Halogenated hydrocarbon based solvents include those represented by
a general formula C.sub.nH.sub.2n-m+2X.sub.m (where n is a positive
integer; m is a positive integer; X is a halogen) such as
octadecafluorooctane. As alkylsiloxane based solvents, linear
silicone solvents represented by a general formula
R.sup.1(R.sup.2R.sup.3SiO).sub.nR.sup.4 (where n is a positive
integer; R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are alkyl groups)
such as hexamethyldisiloxane, cyclic silicone solvents represented
by a general formula (R.sup.1R.sup.2SiO).sub.n(where n is a
positive integer; R.sup.1 and R.sup.2 are alkyl groups) such as
octamethylsiloxane, or arbitrary mixtures of these preferably may
be used.
[0056] As a method in which an organic thin film is formed by
bringing a solution containing the above-mentioned
chlorosilane-based compound into contact with a surface of a
substrate, a coating solution only in a determined amount required
for one time application is dropped on a surface of a substrate,
and the coating solution is spread uniformly on the surface of the
substrate with a coating device. At this time, it is preferable
that the water vapor concentration is maintained within the range
of more than 0.0076 kg/m.sub.3 but not more than 0.0203 kg/m.sub.3.
Under this condition, the chlorosilane-based compound may cause an
elimination reaction with an active hydrogen of a hydroxyl group
etc. on the surface of the substrate, and also molecules of the
chlorosilane-based compound cause an elimination reaction with one
another to be polymerized due to the presence of water, so that it
is firmly bonded to the surface of the substrate. As a result, a
coating film excellent in abrasion resistance and durability can be
formed.
[0057] Furthermore, it is possible to accelerate an elimination
reaction between the reactive group of the silane-based compound at
least in an amount required for one time application and the active
hydrogen on the surface of the substrate by changing the atmosphere
around the substrate, increasing the concentration of the
silane-based compound, and using the coating device, and then
remove the solvent. At this time, molecules of the
chlorosilane-based compound also cause an elimination reaction with
one another to be polymerized due to the presence of water in the
atmosphere, and are bonded firmly to the surface of the
substrate.
[0058] The following compounds are examples of the silane-based
compound that may be used in the present invention:
[0059] (1) CH.sub.3(CH.sub.2).sub.rSiY.sub.pCl.sub.3-p
[0060] (2)
CH.sub.3(CH.sub.2).sub.sO(CH.sub.2).sub.tSiY.sub.pCl.sub.3-p
[0061] (3)
CH.sub.3(CH.sub.2).sub.uSi(CH.sub.3).sub.2(CH.sub.2).sub.vSiY.s-
ub.pCl.sub.3-p
[0062] (4) CF.sub.3COO(CH.sub.2).sub.wSiY.sub.pCl.sub.3-p
[0063] where p is an integer of 0 to 2; r is an integer of 1 to 25;
s is an integer of 0 to 12; t is an integer of 1 to 20; u is an
integer of 0 to 12; v is an integer of 1 to 20; and w is an integer
of 1 to 25; furthermore, Y is a hydrogen, an alkyl group, an
alkoxyl group, a fluorine-containing alkyl group, or a
fluorine-containing alkoxyl group.
[0064] Furthermore, the following (5) to (11) are specific examples
of adsorptive compounds:
[0065] (5) CH.sub.3CH.sub.2O(CH.sub.2).sub.15SiCl.sub.3
[0066] (6)
CH.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15SiCl-
.sub.3
[0067] (7)
CH.sub.3(CH.sub.2).sub.6Si(CH.sub.3).sub.2(CH.sub.2).sub.9SiCl.-
sub.3
[0068] (8) CH.sub.3COO(CH.sub.2).sub.15SiCl.sub.3
[0069] (9) CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCl.sub.3
[0070] (10) CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2SiCl.sub.3
[0071] (11) CF.sub.3(CF.sub.2).sub.7C.sub.6H.sub.4SiCl.sub.3
[0072] Furthermore, instead of the above-mentioned chlorosilane
type silane-based compounds, isocyanate type silane-based compounds
in which isocyanate groups are substituted for all chlorosilyl
groups, e.g. the following (12) to (16), may be used:
[0073] (12) CH.sub.3(CH.sub.2).sub.rSiY.sub.p(NCO).sub.3-p
[0074] (13) CF.sub.3(CH.sub.2).sub.rSiY.sub.p(NCO).sub.3-p
[0075] (14)
CH.sub.3(CH.sub.2).sub.sO(CH.sub.2).sub.tSiY.sub.p(NCO).sub.3--
p
[0076] (15)
CH.sub.3(CH.sub.2).sub.uSi(CH.sub.3).sub.2(CH.sub.2).sub.vSiY.-
sub.p(NCO).sub.3-p
[0077] (16) CF.sub.3COO(CH.sub.2).sub.wSiY.sub.p(NCO).sub.3-p
[0078] where p, r, s, t, u, v, w and Y are the same as the
above.
[0079] Instead of the above-mentioned adsorptive agents, adsorptive
compounds specified in the following (17) to (23) also may be
used:
[0080] (17) CH.sub.3CH.sub.2O(CH.sub.2).sub.15Si(NCO).sub.3
[0081] (18)
CH.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15Si(-
NCO).sub.3
[0082] (19) CH.sub.3(CH.sub.2).sub.6Si(CH.sub.3).sub.2(
CH.sub.2).sub.9Si(NCO).sub.3
[0083] (20) CH.sub.3COO(CH.sub.2).sub.15Si(NCO).sub.3
[0084] (21)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(NCO).sub.3
[0085] (22)
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2Si(NCO).sub.3
[0086] (23) CF.sub.3(CF.sub.2).sub.7C.sub.6H.sub.4Si(NCO).sub.3
[0087] Furthermore, as the silane-based compound, materials
generally represented by SiY.sub.k(OA).sub.4-k (where Y is the same
as the above; A is an alkyl group; and k is 0, 1, 2 or 3) may be
used. Among these, substances represented by a formula
CF.sub.3(CF.sub.2).sub.n(R).sub.qSiY.- sub.p(OA).sub.3-p (where n
is an integer of at least 1, preferably 1 to 22; R is an alkyl,
vinyl, ethynyl or aryl group, or a substituent containing a silicon
or oxygen atom; q is 0 or 1; Y, A and p are the same as the above)
are used, so that a more excellent anti-fouling coating film can be
formed. However, it is not limited to these substances, and for
example, CH.sub.3(CH.sub.2).sub.rSiY.sub.p(OA).sub.3-p and
CH.sub.3(CH.sub.2).sub.sO(CH.sub.2).sub.tSiy.sub.p(OA).sub.3-p,
CH.sub.3(CH.sub.2).sub.uSi(CH.sub.3).sub.2(CH.sub.2).sub.vSi.sub.p(OA).su-
b.32-p and CF.sub.3COO(CH.sub.2).sub.wSiY.sub.p(OA).sub.3-p (where
p, r, s, t, u, v, w, Y and A are the same as the above) also may be
used.
[0088] Furthermore, as more specific examples of the silane-based
compound, the following (24) to (47) may be used:
[0089] (24) CH.sub.3CH.sub.2O(CH.sub.2).sub.15Si(
CH.sub.3).sub.3
[0090] (25)
CF.sub.3CH.sub.2O(CH.sub.2).sub.15Si(OCH.sub.3).sub.3
[0091] (26)
CH.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15Si(-
OCH.sub.3).sub.3
[0092] (27)
CH.sub.3(CH.sub.2).sub.6Si(CH.sub.3).sub.2(CH.sub.2).sub.9Si(O-
CH.sub.3).sub.3
[0093] (28) CH.sub.3COO(CH.sub.2).sub.15Si(OCH.sub.3).sub.3
[0094] (29)
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2Si(OCH.sub.3).sub.3
[0095] (30)
CF.sub.3(CF.sub.2).sub.7C.sub.6H.sub.4Si(OCH.sub.3).sub.3
[0096] (31)
CH.sub.3CH.sub.2O(CH.sub.2).sub.15Si(OC.sub.2H.sub.5).sub.3
[0097] (32)
CH.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15Si(-
OC.sub.2H.sub.5).sub.3
[0098] (33)
CH.sub.3(CH.sub.2).sub.6Si(CH.sub.3).sub.2(CH.sub.2).sub.9Si(O-
C.sub.2H.sub.5).sub.3
[0099] (34)
CF.sub.3(CH.sub.2).sub.6Si(CH.sub.3).sub.2(CH.sub.2).sub.9Si(O-
C.sub.2H.sub.5).sub.3
[0100] (35)
CH.sub.3COO(CH.sub.2).sub.15Si(OC.sub.2H.sub.5).sub.3
[0101] (36)
CF.sub.3COO(CH.sub.2).sub.15Si(OC.sub.2H.sub.5).sub.3
[0102] (37) CF.sub.3COO(CH.sub.2).sub.15Si(OCH.sub.3).sub.3
[0103] (38)
CF.sub.3(CF.sub.2).sub.9(CH.sub.2).sub.2Si(OC.sub.2H.sub.5).su-
b.3
[0104] (39)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(OC.sub.2H.sub.5).su-
b.3
[0105] (40)
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2Si(OC.sub.2H.sub.5).su-
b.3
[0106] (41)
CF.sub.3(CF.sub.2).sub.7C.sub.6H.sub.4Si(OC.sub.2H.sub.5).sub.-
3
[0107] (42) CF.sub.3(CF.sub.2).sub.9(CH.sub.2).sub.2Si(O
CH.sub.3).sub.3
[0108] (43)
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2Si(OCH.sub.3).sub.3
[0109] (44)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCH.sub.3(OC.sub.2H.s-
ub.5).sub.2
[0110] (45)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCH.sub.3(OCH.sub.3).-
sub.2
[0111] (46)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(CH.sub.3).sub.2OC.s-
ub.2H.sub.5
[0112] (47)
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(CH.sub.3).sub.2CH.s-
ub.3
[0113] In the following, specific examples of the method for
producing an organic thin film, the apparatus for producing an
organic thin film, and the organic thin film according to the
present invention are described.
EXAMPLE 1
[0114] A glove box made of a transparent vinyl chloride was
prepared, and was provided with a temperature sensor and a humidity
sensor. The water vapor concentration in the glove box was
controlled constantly by measuring the temperature and relative
humidity in the glove box. The glove box had a construction in
which dry air was introduced from a dry air generator as needed
through a pipe so as to control the water vapor concentration. It
also had a construction in which air passed through a humidifier
was introduced as needed through a pipe.
[0115] In the glove box, a glass sheet of 5 cm square, a vial
containing an agent of octadecyltrichlorosilane (produced by
Shin-Etsu Chemical Co., Ltd.) only in a required amount, and a
glass container to contain the agent were placed. It was ensured
that the temperature in the glove box was stable in the range of 25
to 27.degree. C. for 15 minutes, and the relative humidity in the
glove box was stable in the range of 50 to 56% for 15 minutes.
These ranges of the temperature and relative humidity indicate that
the water vapor concentration is stable in the range of 12 g to 15
g per cube meter.
[0116] Under this condition, one's hand was inserted in the glove
box to put the agent in the glass container, and the glass sheet
was immersed in the agent in the glass container. After immersing
it for one minute, the glass sheet was taken out, and a surface of
the glass sheet was rubbed with a waste (cloth) in the glove box to
wipe off excess solution, dirt, etc. Then, the glass sheet was
taken out of the glove box. The glass sheet retained its
transparency. Furthermore, although the glass sheet before
treatment was wet well with water, the glass sheet after the
above-mentioned treatment exhibited water repellency when immersed
in water and pulled out, and water fell as if flowing. Thus, it was
concluded that an organic thin film had been formed by a reaction
of octadecyltrichlorosilane at least in an amount required for one
time application with the substrate.
EXAMPLE 2
[0117] The same type of experiment as in Example 1 was carried out
in an atmosphere having a high water vapor concentration of 20.3 g
per m.sup.3. A phenomenon on a surface of a glass sheet suggesting
a formation of an organic thin film was confirmed in the same way
as in Example 1.
EXAMPLE 3
[0118] In a clean booth controlled for temperature at 20.degree.
C..+-.2.degree. C. and for relative humidity at 50%.+-.5%, an
organic thin film was formed using a substrate in which a slide was
subjected to aluminum evaporation and further to sputtering with
silicon dioxide. In these controlled ranges of temperature and
humidity, the water vapor concentration ranged from 7.0 g to 11.0 g
per cube meter. A solution of 1% 18-nonadecenyltrichlorosilane
(produced by Shin-Etsu Chemical Co., Ltd.) in anhydrous hexane
(produced by Wako Pure Chemical Ind., Ltd.) was prepared, and the
solution was applied to the substrate with a brush. After five
minutes, the surface of the substrate was rubbed with a nonwoven
fabric containing anhydrous hexane. Using this substrate, an
infrared absorption spectrum was measured by reflection method. As
a result of spectrum analysis, two spectra resulting from CH.sub.2
stretching vibrations were observed near 2900 cm.sup.-1 and 2850
cm.sup.-1, and a spectrum resulting from a CH stretching vibration
of an alkene was observed near 1650 cm.sup.-1. As a result, it
appeared that 18-nonadecenyltrichlorosilane caused a hydrogen
chloride elimination reaction on the surface of the substrate to
form a film. Furthermore, the surface energy was 33 mN/m, and it
was estimated that an organic compound different from a silicon
oxide had been formed on the surface of the substrate.
[0119] Moreover, the system for controlling the water vapor
concentration as shown in Example 1 is a very simple, laboratory
one, and it has a satisfactory construction in which a gas having a
controlled water vapor concentration is introduced.
[0120] Furthermore, when a dry gas and a humid gas are introduced
separately into a place in which a reaction is caused (referring to
the glove box in this example) as in this example, in order to
avoid a localized water vapor concentration outside of the
controlled range, a pre-chamber in which humidities of gases to be
introduced are adjusted may be provided. Particularly, when the
glove box has a small size, it is preferably provided with a
pre-chamber.
[0121] Furthermore, in Example 1, although excess agent, dirt etc.
were removed from the surface by rubbing with a cloth (waste), if
excess agent can be removed naturally, for example, by controlling
viscosity of the agent or using an agent that can be evaporated
easily, rubbing on the surface is of course unnecessary. Moreover,
if there is any measure to drain a liquid from the agent using an
air gun etc., rubbing on the surface also is unnecessary. The same
also applies to Example 3.
EXAMPLE 4
[0122] This example describes a method and an apparatus
for,producing a coating film, using a rotational coating
film-forming apparatus as an example of an apparatus for producing
a coating film of the present invention.
[0123] FIG. 1 is a schematic diagram of a rotational coating
film-forming apparatus. In FIG. 1, a substrate is moved from left
to right, and during the process a coating film is formed on a
surface of the substrate.
[0124] In a chamber 1, air was supplied constantly through an air
flow pipe 2 as shown by an arrow A so as to control and maintain
the water vapor concentration in the chamber 1 in the range of
higher than 0.0076 kg/m.sup.3. A belt conveyor 3 was provided at an
inlet for a substrate. An enamel plate 4 as a substrate to be
coated with an organic thin film was placed on the belt conveyor 3,
and automatically it was introduced into the chamber as shown by an
arrow B. Then, the enamel plate 4 was positioned on a support
5.
[0125] FIG. 2 is a perspective view showing selectively a
rotational coating section in FIG. 1. A nozzle 6 connected to a
container for supplying a coating solution was moved as shown by an
arrow C, and a coating solution was measured in an amount required
for one time application, for example, in an amount of 0.6 ml to
0.8 ml per a plate with a diameter of 20 cm. The measured coating
solution, which is described below, was dropped on the enamel plate
4 at each time of application. The coating solution comprised a
solution in which one weight part of
heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane was
dissolved in 100 weight parts of a cyclic silicone oil, both of
which agents were produced by Shin-Etsu Chemical Co., Ltd.
[0126] Then, an axis 7a of a coating device was rotated, and a
surface of the enamel plate 4 was rubbed uniformly with a nonwoven
fabric 7b. Thus, the coating solution was applied on the entire
surface of the enamel plate 4. In the case of a plate with a
diameter of 20 cm, application of the coating solution on the
entire surface was able to be completed in several seconds.
[0127] Next, the enamel plate was transported by a belt conveyor 8
and sent to another chamber 9. In the chamber 9, a warm air was
supplied through an airflow pipe 10 as shown by an arrow D, and the
temperature in the chamber was maintained at higher than room
temperature. The enamel plate 11 sent to the chamber 9 was
positioned on a support 13, and the coating device 12a was rotated,
so that a surface of the enamel plate was rubbed uniformly with a
nonwoven fabric 12b. The coating solution spread uniformly on the
enamel plate by this operation caused an elimination reaction with
a vitreous component on the surface of the enamel plate. As a
result, as shown in FIG. 2, an organic thin film 16 covalently
bonded to an enamel plate 15 was formed. The solvent in the coating
solution was removed using the atmosphere in the chamber 9, and
only the organic thin film 16 remained on the enamel plate 15.
[0128] Next, the enamel plate 11 was discharged from the chamber 9
by a belt conveyor 14 as shown by an arrow E. Thus, a finished
product of the enamel plate 15, in which an organic thin film was
formed on a surface, was obtained.
[0129] Moreover, although the agent was dropped directly on the
enamel plate in this example, the same film also was able to be
formed by dropping the agent to a nonwoven fabric and causing it to
be absorbed by the nonwoven fabric, followed by rotating the axis
of the coating device as shown in FIG. 3.
Comparative Example 1
[0130] To confirm the effect of the method of the present
invention, a film having a siloxane bond was produced by a
conventional method. The role of maintaining the water vapor
concentration has been described in the above example, while the
cases in which the water vapor concentration was not maintained
also have been exemplified.
[0131] Using the same
heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosila- ne (1 weight
%) as in the above example as a chlorosilane-based compound, and
using octamethylcyclotetrasiloxane as a solvent, the
above-mentioned mixed solution was prepared in a vat. The
atmosphere provided in the vat containing the solution was
maintained for its water vapor concentration to be in the
above-mentioned range, and the same enamel plate as in Example 1
was immersed in the solution. The immersion was carried out for 15
minutes, and then air-drying of the solvent was performed for 15
minutes.
[0132] The state of the surface of the glass sheet after completing
the film forming was measured by dropping water and using an angle
formed by a water drop and the glass sheet (a contact angle).
[0133] Table 1 below shows results of comparison between Example 1
and Comparative Example 1.
1TABLE 1 Production Method Conventional Production Item of
Comparative of Example 1 Method (Comp. Example 1) Evaluation
(Rotational Coating) (Immersion) Measured Contact 110 110 Angle
(degree) Visual Inspection of No Adhered Material White Material
Was Appearance Adhered Amount of Solution 0.75 1800 (g) Time for
Forming a 20 seconds 30 minutes Film
[0134] Table 1 shows a comparison between the case in which a film
was formed on an enamel plate by the method shown in the example
and the case in which a film was formed on the same enamel plate by
the method shown in the comparative example, with respect to
contact angle, visual inspection of appearance, amount of solution
prepared, and time for forming a film. Both of the contact angles
of the formed films were 110 degree, and the states of the surfaces
were the same. On the other hand, in the conventional method,
because the specified condition of water vapor concentration after
immersion was incomplete, many adhered white materials were
generated on the glass sheet according to visual inspection of
appearance. However, in the method of the present invention, such
an adhered material was not confirmed.
[0135] Furthermore, according to the method of the present
invention, the amount of the solution of the chlorosilane-based
compound used per one enamel plate was 0.75 g. In the conventional
method, because the solution was prepared in an amount required for
immersing the enamel plate, 1800 g of the solution, which was 2400
times larger than the amount in the present invention, was
required. In the conventional method, the solution after preparing
a film on a first substrate contains enough chlorosilane-based
compound to form a film, so that of course a film can be formed
when a second substrate is immersed in that solution, and films can
be formed on a plurality of substrates. Thus, it cannot be
generally said that an amount exceeding 2000 times is required.
However, although a film can be formed with a proper amount of the
solution at each time according to the method of the present
invention, it is necessary to prepare as much as 1800 g of the
solution in this example of the conventional immersion method, even
when a film is to be formed on a single substrate. Thus, the method
of the present invention is more excellent than the conventional
method to form a film depending on the requirements for each
production. Accordingly, the cost required for forming a film can
be reduced. Moreover, the method of the present invention is also
more excellent than the conventional method in terms of storability
of the solution, etc.
[0136] Furthermore, there was an obvious difference in the time for
forming a film. In the example of the present invention, a film was
able to be formed on a single enamel plate in 20 seconds, and
moreover, it was confirmed that the film was free of problems in
visual inspection of appearance. On the other hand, in the
conventional immersion method, 30 minutes was required to form a
film, and this was 90 times longer than the time required in the
present invention. Also, the quality of the formed product was not
very good. Thus, there is also a large difference in the number of
films formed per unit time, and this also shows that the present
invention is excellent in reducing the cost of forming a film.
[0137] Another difference between the method of the present
invention and the conventional immersion method is that while a
film is formed on one side of a substrate in the present invention,
a film is formed on both sides in the conventional method. If it is
necessary to form a film only on one side by the conventional
method, measures must be taken in advance to cover the side not
needed to be coated, so that no reaction of forming a film may
occur on that side. Moreover, when effect on only one side is
sufficient, because films are formed on both sides in the
conventional method, an excess film is formed on an unneeded side,
and the cost of forming a film is doubled.
COMPARATIVE EXAMPLE 2
[0138] As a comparative example, a roll coating method is
mentioned. JP-10-180179 A shows details of this method. The roll
coating method is very excellent to form a film on a flat plate.
However, if the substrate is not a flat plate as shown in Example
1, the roll coating method cannot be used. This indicates an
obvious difference.
Comparative Durability Test
[0139] Durability was evaluated for the enamel plate coated with an
organic thin film as produced in Example 1, and an enamel plate
produced in an atmosphere having a water vapor concentration of
less than 0.0076 kg/m.sup.3. As an example of a fouling, a mixture
of sugar and soy source (1:1 by weight ratio) was applied to the
enamel plate coated with an organic thin film, heated to a high
temperature of 300.degree. C. for 20 minutes and cooled, and then
the fouling baked and adhered to the enamel plate was removed by
rubbing it with a wet cloth by one's hand. This was because wiping
off with one's hand was the most practical measure to remove a
fouling. The operation was repeated until the fouling was not able
to be removed, and the number of repeated cycles was counted. Table
2 shows the result.
2TABLE 2 Water Vapor Concentration (kg/m.sup.3) 0.0021 0.0060
0.0076 0.0150 0.0169 0.0203 Number of 0 2 6 8 6 5 Possible Fouling
Removal Evaluation X X .largecircle. .circleincircle. .largecircle.
.largecircle.
[0140] In Table 2, .circleincircle. indicates at least 8 times of
possible fouling removal (determined as the best durability and
abrasion resistance with practicability); .largecircle. indicates
at least 5 but less than 8 times of possible fouling removal
(determined as good durability and abrasion resistance with
practicability); and .chi. indicates less than five times of
possible fouling removal (determined as poor durability and
abrasion resistance without practicability).
[0141] As a result of this test, it was evident that durability was
poor in the cases of low water vapor concentrations, and a sharp
increase in durability was confirmed with a borderline at about
0.0076 kg/m.sup.3 of water vapor concentration. Thus, the organic
thin films formed with a water vapor concentration of higher than
0.0076 kg/m.sup.3 did not peel off, and exhibited very good
abrasion resistance as thin films. Moreover, in this environmental
test, it was impossible to produce an atmosphere having a water
vapor concentration of higher than 0.0203 kg/m.sup.3.
[0142] As mentioned above, the organic thin film formed on a
substrate by the method of the present invention was free of a
white adhered material, and had more durability than a film formed
by the conventional method.
[0143] When the enamel plate obtained as in the above was used as a
heat cooking plate in a microwave or electronic oven, a fouling was
able to be wiped off easily. Moreover, it also had durability and
was very useful.
EXAMPLE 5
[0144] A coating device shown in FIG. 5 was placed in a room
(chamber) in which a water vapor concentration in air was
controlled and maintained in the range of more than 0.0076
kg/m.sup.3. For perfect operation, the coating device was provided
with a cover 18 and an air supply pipe 19 for supplying air having
an adjusted water vapor concentration, particularly in a section
for forming an organic thin film, so that an artificial increase in
the water vapor concentration was inhibited. A glass sheet 20
having a bend in part (for example, a glass sheet having a bend
extending upward only at the right lower angle is illustrated in
FIG. 5) was set in the coating device by hand. The glass sheet was
not placed horizontally as in Example 1, but was placed in an
obliquely vertical direction. A nozzle 21 extended from a side, and
the same coating solution as in Example 1 was dropped from the
nozzle 21 on a surface of the glass sheet. At the same time, the
coating solution was spread uniformly on the surface of the glass
sheet with a sponge coater 22 attached to a crossarm extending from
a side. The nozzle and the sponge coater were simultaneously moved
up and down and right and left in concert as shown by an arrow in
FIG. 5, spreading the solution uniformly on the glass sheet while
dropping it. The sponge coater was rotated to enable easy spreading
of the coating solution. The sponge coater dealt with the bend of
the glass sheet by deforming, and made it possible to coat the bend
smoothly.
[0145] Next, as shown in FIG. 6, a dryer 23 having an opening for
blowing a dry warm air and a sponge coater 24 different from the
above sponge coater were used to form an organic thin film. A glass
surface of the glass sheet 20 applied with a coating solution was
rubbed with the sponge coater, and at the same time a dry warm air
was applied thereto so as to form an organic thin film. The dryer
23 having an opening for blowing a dry warm air and the sponge
coater 24 were simultaneously moved up and down and right and left
in concert as shown by an arrow in FIG. 6. Then, the glass sheet 20
was removed by one's hand.
[0146] According to this device and the method for forming an
organic thin film, an organic thin film comprising mainly carbon
fluoride was able to be formed on a special shaped glass sheet
having a bend in part (e.g. a windshield glass of an
automobile).
[0147] Although two chambers were used in Example 1, the treatment
can be performed with one chamber, if the water vapor concentration
can be controlled and maintained, and if the atmosphere does not
change when warm air required in the next step is supplied.
[0148] Furthermore, although warm air was used in Example 1, the
change of the atmosphere in the chamber also can be accomplished by
changing the gas flow rate or the temperature of the substrate. In
the case of changing the gas flow rate, it can be accomplished by
providing a nozzle near the coating device and supplying air or the
like from the nozzle. In the case of changing the temperature of
the substrate, it can be accomplished by providing the support with
a heating device to increase the temperature of the substrate. Of
course, it also may be carried out by other measures.
[0149] Furthermore, although a method in which the water vapor
concentration in the entire room is controlled and maintained is
shown in Example 5, because a change from people coming in and out
cannot be dealt with in practice, the cover was provided. The cover
was necessary only in this example, and it is not required if the
water vapor concentration in the entire room can be controlled with
more precision.
[0150] Furthermore, although the coating solution was supplied by
dropping it with a nozzle in Examples 1 and 5, it also can be
supplied as a spray or a mist.
[0151] As mentioned above, according to the present invention, a
film can be formed on an irregular shaped substrate of a large
size, and productivity can be improved considerably compared to the
conventional immersion method, so that production cost can be
reduced considerably. Thus, it has a large industrial value.
EXAMPLE 6
[0152] FIG. 7 is a schematic diagram of a rotational coating
film-forming apparatus of one example of the present invention.
When forming an organic thin film on an inner surface of a hollow
ceramic substrate 30 having a bottom, which is called a cocotte (a
soup container), an organic thin film can be formed on the inner
surface by using a sponge wiper 31 contacting the inner surface and
rotating the wiper with a rotational axis 32. When the hollow
substrate is long in shape, an organic thin film can be formed by
moving the rotational axis 32 up and down to move the wiper 31 up
and down. Moreover, in the process of forming an organic thin film
shown in FIG. 7, the water vapor concentration is controlled and
maintained in the range of more than 0.0076 kg/m.sup.3. When
applying an agent to a substrate of such a shape, it is preferable
that the agent is supplied by causing it to be absorbed by the
wiper as shown in Example 1.
EXAMPLE 7
[0153] FIG. 8 is a schematic diagram of a rotational coating
film-forming apparatus of one example of the present invention.
When forming an organic thin film on an outer surface of a
cylindrical substrate 33, such as a soup container or a glass
tumbler as in Example 6, an organic thin film can be formed on the
outer surface by using a cylindrical sponge wiper 34 contacting the
outer surface and rotating the wiper with a rotational axis 35.
When the outer surface is long, a uniform organic thin film can be
formed by moving the rotational axis 35 up and down to move the
wiper 34 up and down as shown in FIG. 8. When applying an agent to
a substrate of such a shape, it is preferable that the agent is
supplied by causing it to be absorbed by the wiper as shown in
Example 1. Moreover, in the process of forming an organic thin film
shown in FIG. 8, the water vapor concentration is controlled and
maintained in the range of more than 0.0076 kg/m.sup.3.
EXAMPLE 8
[0154] A case in which an organic thin film of the present
invention is formed on a flat plate is described. As shown in FIG.
9, an organic thin film can be formed by using a sponge wiper 40
corresponding to the length of one side of a flat plate 41 and
dropping an agent on the flat plate 41 or onto the wiper, and then
moving the wiper 40 on the flat plate 41 as shown by an arrow in
FIG. 9. Other conditions are the same as in Example 1.
EXAMPLE 9
[0155] A case in which an organic thin film of the present
invention is formed on a flat plate is described. As shown in FIG.
10, a uniform organic thin film can be formed by dropping an agent
on a flat plate 42 or onto the wiper, and then moving the flat
plate 42 while rotating a sponge wiper 43 with a rotational axis
44, or moving the rotational axis 44 back and forth and right and
left. Other conditions are the same as in Example 1.
EXAMPLE 10
[0156] A case in which an organic thin film of the present
invention is formed on a flat plate 45 having a swelling at its
periphery as shown in FIG. 11 (a cooking tray for restaurant) is
described, among cases in which an organic thin film of the present
invention is formed on a flat plate. A uniform organic thin film
can be formed by using a sponge wiper 46 as shown in FIG. 11, whose
end is curved corresponding to the swelling of the plate, and a
rotational axis 47 capable of moving back and forth and right and
left as shown by an arrow in FIG. 11. Furthermore, an organic thin
film also can be formed by moving the flat plate 45 back and forth
and right and left, instead of moving the rotational axis 47 back
and forth and right and left as in Example 9. Other conditions are
the same as in Example 1.
EXAMPLE 11
[0157] FIG. 12 shows a flow diagram to explain the following
example.
[0158] A restaurant-managing company A owns ceramic and glass
products for food and drink (plates (101) are exemplified here),
which has been processed for a water repellent surface treatment.
Because these products has generated irregularity in the surface
treatment, the company A decides to proceed to repair the surface
treatment of these products on the next regular holiday. The
company A transmits a request for repair treatment to a water
repellent surface treatment company B through the Internet work 103
as an information transfer system, using a personal computer 102 as
an information transmitter. The company B receives the request from
the company A using a personal computer 104, which is an
information receiver present in the company B. The company B also
can obtain information on the location and method of contact of the
company A, and contents of the articles for treatment (e.g. date of
the latest treatment, number and materials of the articles owned by
the company A, content of the surface treatment, etc.) using a
personal computer 105, which is an information processing mechanism
present in the company B. The company B also prepares to send a
product-repair system 106 to the company A on the date specified by
the company A.
[0159] The company B provides the product-repair system 106 owned
by the company B on the date and at the location specified by the
company A. The company carries out a surface treatment of the
plates 101, which are representative examples of the ceramic and
glass products for food and drink requested for treatment by the
company A. Then, right after the treatment, the company B delivers
the products to the company A.
[0160] Furthermore, although the Internet has been described as an
example of an information transfer system, as long as the same
function can be realized, other methods such as a simple
information transfer system using a telephone line etc. also may be
used.
[0161] Furthermore, although a personal computer also has been
described as an example of an information transmitter, as long as
the same function can be realized, a digital phone or a digital
facsimile etc. also may be used as an information transmitter.
[0162] Furthermore, although a personal computer has been described
as an example of an information receiver, as long as the same
function can be realized, a digital phone or a digital facsimile
etc. also may be used as an information receiver.
[0163] Furthermore, when there is a function of selecting and
providing information on the address etc. of the source of the
transmitted information and the articles, it is not necessary to
use a personal computer as shown in the example. Therefore,
large-sized computers, mechanical information selectors, data
cards, and the like also can be used as an information processing
mechanism for substitute.
[0164] FIG. 13 is a scheme of a product-repair system, which
comprises a temperature and humidity controlling device 111 and a
chlorosilane-based material reaction device 112, and further
provided with a product-for-repair supplying device 113 and a
product-after-repair collecting device 114. The product-for-repair
supplying device 113 has a mechanism for conveying a product for
repair, which is usually of a belting system. A product for repair
can be put in the chlorosilane-based material reaction device 112
by conveyance. The chlorosilane-based material reaction device
comprises a rubbing film-forming structure, a material-supplying
structure, an exhauster and a ventilator. The product-after-repair
collecting device 114 is of a belting system, and can collect
products after repair by conveyance. The temperature and humidity
controlling device controls the temperature and humidity of the
entire product-repair system, and particularly controls strictly
the temperature and humidity in the vicinity of the
chlorosilane-based material reaction device.
[0165] Furthermore, although the product-for-repair supplying
device 113 and the product-after-repair collecting device 114 have
been described as being of a belting system, a roller system or a
chuck system also may be employed as needed.
[0166] Furthermore, although a rubbing system has been exemplified
in the chlorosilane-based material reaction device 112, when the
device has a mechanism for spreading an agent uniformly on a
substrate such as a spray system or a roll system, such may be
substituted.
[0167] Referring to FIG. 14, a film-forming mechanism of a rubbing
system is described in detail. A ceramic plate 121 for a surface to
be repaired (a plate is herein exemplified as a substrate) is
placed on a carrier belt 122, moved under an agent-dropping nozzle
123, and a chlorosilane-based material is dropped from the nozzle
123. The dropped chlorosilane-based material is spread uniformly by
rotating a rotational jig 124 for application and reaction (the
portion of the jig contacting the plate is surrounded with a
cloth). At this time, a hydroxyl group having an active hydrogen is
exposed in a portion in which a film is peeled and the plate
substrate is bared. The hydroxyl group and the chlorosilane group
of the material cause a hydrogen chloride elimination reaction to
generate a chemical bonding with the substrate, so that a film of
the material is formed on the portion in which a hydroxyl group is
exposed. On the other hand, in a portion in which a film still
remains, because a hydroxyl group having an active hydrogen is not
exposed, the agent is put on the plate without causing a reaction
between the material and the plate.
[0168] In the next step, excess of the material is wiped out with a
cloth similarly surrounding a rotational jig 125 for wiping. At
this time, the material put on the plate without causing a reaction
is wiped out with this cloth, and repair is completed.
[0169] Furthermore, it is also possible to form a new film after
peeling the entire film prior to the film-forming treatment. In
this case, an agent for peeling the film is required. When the film
has been formed using a chlorosilane-based material, an alkaline
solution is suitably used for the peeling, and a turbid solution
containing an abrasive also may be used to remove the film. When
the film has been formed using a material other than a
chlorosilane-based material, it can be removed easily with an
organic solvent etc. Then, the above-mentioned film-forming
treatment is carried out.
[0170] FIG. 15 is a scheme of a vehicle 131 loaded with a
film-repairing apparatus. FIG. 16 is a representative schematic
diagram of the film-repairing apparatus in the vehicle 131. The
vehicle loaded with a film-repairing apparatus can repair a film
using a chlorosilane-based material, and is in a form of a vehicle,
which is movable.
[0171] The film-repairing apparatus loaded on the vehicle 131
comprises a temperature and humidity controlling device and a
chlorosilane-based material reaction device 141, and further
comprises a product-for-repair supplying device 142 and a
product-after-repair collecting device 143. The chlorosilane-based
material reaction device illustrates the film-forming system shown
in FIG. 14 as an example.
[0172] Thus, according to the present invention, ceramic and glass
products, which need repair of a surface treatment, can be repaired
in a short time at a low cost. Therefore, the contribution of the
present invention is significant.
[0173] Finally, it is understood that the invention may be embodied
in other specific forms without departing from the spirit or
essential characteristics thereof The embodiments disclosed in this
application are to be considered in all respects as illustrative
and not restrictive, so that the scope of the invention being
indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are intended to be embraced
therein.
* * * * *