U.S. patent application number 09/892530 was filed with the patent office on 2001-11-08 for chemically adsorbed film and method of manufacturing the same.
Invention is credited to Mino, Norihisa, Ogawa, Kazufumi, Ohtake, Tadashi.
Application Number | 20010038916 09/892530 |
Document ID | / |
Family ID | 12687350 |
Filed Date | 2001-11-08 |
United States Patent
Application |
20010038916 |
Kind Code |
A1 |
Ohtake, Tadashi ; et
al. |
November 8, 2001 |
Chemically adsorbed film and method of manufacturing the same
Abstract
A highly dense chemically adsorbed film is formed by repeating
the alternate process of adsorption reaction and washing.
Adsorption reaction is directed by contacting the substrate
surface, which has or is given an alkali metal or a functional
group, with a chemical adsorbent, having halosilyl or alkoxysilyl
groups at the end of molecules. An unreacted chemical adsorbent is
then washed away from the substrate surface. The alternate
treatment of adsorption reaction and washing is repeated, thereby
covalently bonding a chemically adsorbed film to the substrate
surface. As a result, a chemically adsorbed film is formed in which
stem molecules are directly or indirectly covalently bonded to the
substrate surface via at least one element chosen from the group
consisting of Si, Ge, Sn, Ti, Zr, S or C and graft molecules are
covalently bonded to at least one element chosen from Si, Ge, Sn,
Ti, Zr, S or C via at least one bond chosen from --SiO--, --GeO--,
SnO--, --TiO--, ZrO--, --SO.sub.2--, --SO-- and --C--.
Inventors: |
Ohtake, Tadashi; (Osaka,
JP) ; Mino, Norihisa; (Osaka, JP) ; Ogawa,
Kazufumi; (Osaka, JP) |
Correspondence
Address: |
Peter J. Davis
Morrison & Foerster LLP
Suite 5500
2000 Pennsylvania Avenue, N.W.
Washington
DC
20006-1888
US
|
Family ID: |
12687350 |
Appl. No.: |
09/892530 |
Filed: |
June 28, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09892530 |
Jun 28, 2001 |
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08306517 |
Sep 15, 1994 |
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6277444 |
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08306517 |
Sep 15, 1994 |
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08021120 |
Feb 23, 1993 |
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Current U.S.
Class: |
428/411.1 |
Current CPC
Class: |
B05D 1/185 20130101;
Y10T 428/261 20150115; Y10T 428/31504 20150401; B82Y 40/00
20130101; Y10T 428/31663 20150401; B82Y 30/00 20130101 |
Class at
Publication: |
428/411.1 |
International
Class: |
B32B 009/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 2, 1992 |
JP |
4-044289 |
Claims
We claim:
1. A chemically adsorbed film comprising stem molecules and graft
molecules, wherein said film is applied to a substrate surface,
wherein stem molecules are directly or indirectly covalently bonded
to said substrate surface using at least one element chosen from
the group consisting of Si, Ge, Sn, Ti, Zr, S or C, and wherein
graft molecules are covalently bonded to at least one element
chosen from the group consisting of Si, Ge, Sn, Ti, Zr, S or C
using at least one bond chosen from the group consisting of
--SiO--,--GeO--, --SnO--, --SnN--, --TiO--, -ZrO--, --SO.sub.2--
and --C--.
2. The chemically adsorbed film according to claim 1, wherein
covalent bonding between said stem molecules and said substrate
surface employs at least one bond chosen from the group consisting
of --SiO--, --SiN--, --GeO--, --GeN--, --SnO--, --SnN--, --TiO--,
--TiN--, --ZrO-- and --ZrN--.
3. The chemically adsorbed film according to claim 1, wherein the
stem molecules or graft molecules additionally comprise a
hydrocarbon chain, a fluorocarbon chain, an aromatic group, or a
heterocyclic group.
4. The chemically adsorbed film according to claim 1, wherein an
unsaturated bond is present in stem or graft molecules.
5. The chemically adsorbed film according to claim 1, said
chemically adsorbed film comprising a monomolecular chemically
adsorbed built-up film.
6. A method of manufacturing a chemically adsorbed film, whereby
graft molecules are bonded to stem molecules, comprising: (1)
providing a substrate surface, wherein said surface comprises
active hydrogens or an alkali metal, and contacting said surface
with chemical admolecules, wherein said admolecules contain
functional groups shown in formula [A] or formula [B]; promoting a
dehydrochlorination or alcohol elimination reaction, thereby
covalently bonding said chemical admolecules into stem molecules;
removing unreacted chemical admolecules; reacting the substrate
surface with water and substituting one or more members of the
group consisting of a halogen group and an alkoxyl group with a
hydroxyl group; wherein Formula [A] comprises the designation --AXm
where X represents halogen, A represents Si, Ge, Sn, Ti, Zr, S or
C, and m represents 2 or 3; further wherein Formula [B] comprises
the designation --A(Q)m where Q represents an alkoxyl group, A
represents Si, Ge, Sn, Ti, Zr, S or C, and m represents 2 or 3; and
(2) contacting said substrate surface with chemical admolecules
containing at least one functional group chosen from the group
consisting of formulas [C], [D], [E], [F], or [G], thereby
promoting a dehydrochlorination, water elimination or alcohol
elimination reaction, and removing unreacted chemical admolecules
and reacting the substrate surface with water; wherein Formula [C]
comprises the designation --AX.sub.n where X represents halogen, A
represents Si, Ge, Sn, Ti, Zr, S or C, and n represents 1, 2 or 3;
further wherein Formula [D] comprises the designation --A(Q).sub.n
where Q represents an alkoxyl group, A represents Si, Ge, Sn, Ti,
Zr, S or C, and n represents 1, 2 or 3; further wherein Formula [E]
comprises the designation --SO.sub.2X where X represents halogen;
further wherein Formula [F] comprises the designation --SOX where X
represents halogen; further wherein Formula [G] comprises the
designation >N--CHO or --OCHO.
7. The method of manufacturing a chemically adsorbed film according
to claim 6, wherein unreacted chemical admolecules are removed by a
nonaqueous solution.
8. The method of manufacturing a chemically adsorbed film according
to claim 6, wherein stem or graft molecules are reacted with
water.
9. The method of manufacturing a chemically adsorbed film according
to claim 6, wherein a chemical adsorbent having
trichlorosilane-based ends is used as a stem or graft molecule.
10. The method of manufacturing a chemically adsorbed film
according to claim 6, wherein a condensation reaction is promoted
by contact with stem or graft molecules in a dehydrochlorination or
alcohol elimination reaction.
11. The method of manufacturing a chemically adsorbed film
according to claim 6, wherein said stem or graft molecules comprise
a hydrocarbon chain, a fluorocarbon chain, an aromatic group or a
heterocyclic group.
12. The method of manufacturing a chemically adsorbed film
according to claim 6, wherein an unsaturated bond is contained in
said stem or graft molecules.
Description
FIELD OF THE PRESENT INVENTION
[0001] The invention relates to a chemically adsorbed film and
method of manufacturing the same; more particularly, the invention
relates to a chemically adsorbed film and its method of
manufacture, in which the molecules are, as a whole, densely
connected to the substrate surface by chemically bonding graft
molecules to chemically adsorbed stem molecules.
BACKGROUND OF THE INVENTION
[0002] Conventional methods used for manufacturing chemically
adsorbed film include the procedure mentioned, for example, on page
92, volume 102 of the Journal of American Chemical Society (J.
Sagiv et al., Journal of American Chemical Society, 92, 102 (1980))
and page 851 of the sixth volume of Langmuir (K. Ogawa et al.,
Langmuir, 6, 851 (1990)). In this method, a chemically adsorbed
film is manufactured by a dehydrochlorination reaction between
groups exposed on a substrate surface, such as dehydroxyl groups,
and a chlorosilane-based surface active material. The adsorption
reaction is carried out for many hours until it reaches the point
of saturation adsorption. To form one chemically adsorbed film, an
adsorption reaction, a washing and a rinsing are performed
once.
[0003] However, the above-noted method is limited in improving film
density; the number of functional groups of the group itself sets
an upper limit on the site number for the adsorption reaction of
chemically adsorbed material. As a result, based on the above-noted
method, there is a problem that film density can not be improved
even by significantly lengthening the time for adsorption
reaction.
[0004] The method of building up chemical admolecules on a
chemically adsorbed film (U.S. Pat. No. 4,673, U.S. Pat. No.
4,992,300) is also known as a conventional method. However, it is
difficult to increase the density of molecules on the substrate
surface using this method.
SUMMARY OF THE INVENTION
[0005] An objective of the invention is to provide a chemically
adsorbed film with improved film density, while detailing its
method of manufacture, thereby solving the above-noted
problems.
[0006] To accomplish the above objective, the chemically adsorbed
film of this invention is formed by a direct or indirect covalent
bonding of stem molecules to the substrate surface via at least one
element chosen from Si, Ge, Sn, Ti, Zr, S or C. Graft molecules are
covalently bonded to at least one element chosen from Si, Ge, Ti,
Zr, S or C via at least one bond chosen from --SiO--, --GeO--,
--SnO--, TiO--, ZrO--, --SO.sub.2--, --SO-- and --C--.
[0007] In the above-noted composition, it is preferable that direct
or indirect covalent bonding between stem molecules and the
substrate surface employs at least one bond chosen from the
following: --SiO--,--SiN--, --GeO--, --GeN--, --SnO--, --SnN--,
--TiO--, --TiN--, --ZrO-- and --ZrN--.
[0008] In the above-noted composition, it is preferable that a stem
or graft molecule contains a hydrocarbon chain, a fluorocarbon
chain, an aromatic group or a heterocyclic group.
[0009] In the above-noted composition, it is preferable that an
unsaturated bond is included in a stem or graft molecule.
[0010] In the above-noted composition, it is preferable that a
chemically adsorbed film is a monomolecular chemically adsorbed
built-up film.
[0011] The method of manufacturing a chemically adsorbed film of
the invention, which is the method of bonding graft molecules to
stem molecules, comprises the following procedures:
[0012] (1) directly or indirectly contacting the chemical
admolecules, containing functional groups as shown in formula [A]
or formula [B] at the end of molecules, with the substrate surface,
which either has or is given an active hydrogen or alkali metal on
the surface, thereby covalently bonding the chemical admolecules,
stem molecules, to the substrate surface by condensation
reaction;
[0013] removing unreacted chemical admolecules;
[0014] reacting the substrate surface with water, thereby
substituting the halogen or alkoxyl group, or both, to a hydroxyl
group.
[0015] Formula [A] is provided as seen below:
--AXm
[0016] where X represents halogen, A represents Si, Ge, Sn, Ti. Zr,
S or C, m represents 2 or 3.
[0017] Formula [B] is represented by:
--A(Q)m
[0018] where Q represents an alkoxyl group, A represents Si, Ge,
Sn, Ti, Zr, S or C, m represents 2 or 3.
[0019] The method additionally comprises contacting the substrate
surface with chemical admolecules containing at least one
functional group at the end of molecules, chosen from formulas [C]
through [G], thereby creating a condensation reaction;
[0020] removing unreacted chemical admolecules;
[0021] reacting the substrate surface with water.
[0022] Formula [C] is designated:
--AXn
[0023] where X represents halogen, A represents Si, Ge, Sn, Ti, Zr,
S or C, n represents 1, 2 or 3.
[0024] Formula [D] is designated:
--A(Q)n
[0025] where Q represents an alkosyl group, A represents Si, Ge,
Sn, Ti, Zr, S or C, n represents 1, 2 or 3.
[0026] Formula [E] is designated:
--SO.sub.2X
[0027] where X represents halogen.
[0028] Formula [F] is represented by:
--SOX
[0029] where X represents halogen.
[0030] Formula [G] is denoted by:
>N--CHO or --OCHO
[0031] In the above-noted composition, it is preferable that
unreacted chemical admolecules are removed by a nonaqueous
solution.
[0032] In the above-noted composition, it is preferable that either
liquid water or steam is used in the process of reacting stem or
graft molecules with water.
[0033] In the above-noted composition, it is preferable that the
chemical adsorbent, which contains trichlorosilane-based ends, is
used as stem or graft molecules.
[0034] In the above-noted composition, it is preferable that the
condensation reaction due to the contact with stem or graft
molecules is a dehydrochlorination, alcohol elimination or water
elimination reaction.
[0035] In the above-noted composition, it is preferable that a
hydrocarbon chain, a fluorocarbon chain, an aromatic group or a
heterocyclic group is included in stem or graft molecules.
[0036] In the above-noted composition, it is preferable that an
unsaturated bond is included in stem or graft molecules.
[0037] Based on this invention, the density of a chemically
adsorbed film is improved by increasing the number of admolecules.
More specifically, the number of admolecules can be increased by
the rise in the site number, which is promoted by introducing graft
molecules to the roots of stem molecules. In addition, it is
possible that graft molecules are directly bonded to the
substrate.
[0038] Based on the preferable composition of the invention, direct
or indirect covalent bonding of stem molecules to the substrate
surface employs at least one bond chosen from --SiO--, --SiN--,
--GeO--, --GeN--, --SnO--, --SnN--, --TiO--, --TiN--, --ZrO-- and
--ZrN--, thus allowing a molecular adsorption film to become
chemically stable.
[0039] In a preferable composition of the invention--with an
unsaturated bond in the hydrocarbon chain of stem or graft
molecules--it is possible to polymerize stem and/or graft molecules
or to introduce another molecule after the formation of a
chemically adsorbed film. It is preferable that the unsaturated
bond is the double bond of carbon-carbon (C.dbd.C), the double bond
of carbon-nitrogen (C.dbd.N), the triple bond of carbon-carbon
(C.ident.C), the triple bond of carbon-nitrogen (C.ident.N) or the
like.
[0040] Furthermore, a preferable composition of the invention is a
chemically adsorbed film and a monomolecular chemically adsorbed
built-up film, whereby a film with increased molecular density is
formed.
[0041] In the method of manufacturing a chemically adsorbed film of
the invention, said film with improved film density efficiently may
be formed by increasing the number of admolecules, which is made
possible by increasing the site number. Moreover, this method can
reduce the reaction time.
[0042] According to a preferable composition of the invention, the
unreacted chemical admolecules are removed by a nonaqueous
solution, and a film with a thickness at an angstrom or nanometer
level is uniformly formed over the substrate surface.
[0043] In a preferable composition of the invention, stem or graft
molecules are reacted with liquid water or steam, a halogen atom
can be substituted for a hydroxyl group quite efficiently.
[0044] The above-noted method of using the chemical adsorbent with
trichlorosilane ends as the stem or graft molecules is quite
practical, providing a high adsorption reaction.
[0045] A preferable composition of the present invention comprises
a condensation reaction due to the contact with stem or graft
molecules in a dehydrochlorination, alcohol elimination or water
elimination reaction, whereby a high reaction rate is possible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] FIG. 1 is a model view, enlarged to a molecular level,
showing the substrate of one example according to the
invention.
[0047] FIG. 2 is a model view, enlarged to a molecular level,
showing the chemically adsorbed monomolecular film of the example
according to the invention.
[0048] FIG. 3 is a model view, enlarged to a molecular level,
showing another chemically adsorbed monomolecular film of the
example according to the invention.
[0049] FIG. 4 is a model view, enlarged to a molecular level,
showing the chemically adsorbed monomolecular film of another
example according to the invention.
[0050] FIG. 5 is a model view, enlarged to a molecular level,
showing another chemically adsorbed monomolecular film of the
example according to the invention.
[0051] FIG. 6 is a model view, enlarged to a molecular level,
showing the chemically adsorbed monomolecular film of another
example according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0052] The method of manufacturing a chemically adsorbed film of
the invention comprises fixing a chemical adsorbent to a substrate
and chemically adsorbed film by repeating the alternate process of
adsorption reaction and washing. Particularly, even in case the
first adsorption reaction process is not completely directed
without reaching the stage of unsaturated adsorption, the number of
--OH groups is increased. This result is obtained by removing
unreacted molecules with a nonaqueous solvent and by washing the
substrate, which has only scattered admolecules on its surface,
with water. After the second adsorption reaction, more than two
admolecules are found where only one admolecule was originally
contained. In this process, the distance between admolecules is
decreased mutually and uniformly, thereby increasing the film
density.
[0053] However, if the time spent for the adsorption reaction is
too short, the adsorbed molecules will be scattered over the
substrate at wide distances from one another. As a result, the
admolecules can bend, become parallel to the substrate, or cover
the original sites for adsorption. In order to prevent such
undesirable results, more than several minutes are required for the
adsorption reaction.
[0054] Under standard reaction conditions, however, it is quite
likely that the reaction rate is too fast to enable control of the
time for adsorption reaction. In this case, the association or
collision rates between the reactive groups of the chemical
adsorbent and the active hydrogen groups of a substrate can be
reduced by lowering the temperature of the reaction or the
concentration of adsorbent; as a result, the time for the reaction
is extended and thus becomes quite manageable.
[0055] In this invention, a chemical adsorbent may be provided as
recited below:
[0056] a molecule in which a halosilyl group as shown in formula
[C] is bonded to the end of molecule--containing a hydrocarbon
chain, a fluorocarbon chain, an aromatic ring, a heterocyclic ring,
metal or the like;
[0057] a molecule in which an alkoxysilyl or aldehydesilyl group as
shown in formula [D] is bonded to the end of molecule--containing a
hydrocarbon chain, a fluorocarbon chain, an aromatic ring, a
heterocyclic ring, metal or the like;
[0058] a molecule in which at least one functional group chosen
from halogenated sulfonyl groups as shown in formulas [E] and [F]
and an aldehyde group as shown in formula [G] is bonded to the end
of molecules--containing a hydrocarbon chain, a fluorocarbon chain,
an aromatic ring, a heterocyclic ring, metal or the like.
[0059] However, it is preferable that halosilyl group is either
dihalosilyl or trihaloxilyl group. Similarly, alkoxysilyl group
should be either dialkoxysilyl or trialkoxysilyl group. In terms of
reactivity, Cl is prefered to Br or I as a halogen. However, a
similar-chemically adsorbed film can be formed even with Br or
I.
[0060] When the adsorption reaction is carried out more than once,
the kind of chemical adsorbent can be changed each time. In spite
of the fact that the film density is affected by the change of
adsorbent, the density can be controlled in many cases.
[0061] The increase or control of film density is applicable not
only to the case of forming one film on the substrate but to
forming a multilayer film on the existing chemically adsorbed
film.
[0062] The following can be used as chemical adsorbents in this
invention:
[0063] (1) trichlorosilane-based surface active materials
including
[0064] CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCl.sub.3,
[0065] CF.sub.3CH.sub.2O(CH.sub.2).sub.15SiCl.sub.3,
[0066]
CF.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15SiC.sub.-
3,
[0067]
CF.sub.3(CH.sub.2).sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2-
).sub.9SiCl.sub.3,
[0068]
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2-
).sub.9SiC.sub.3,
[0069] CF.sub.3COO(CH.sub.2).sub.15SiCl.sub.3, or
[0070] CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2SiCl.sub.3
[0071] (2) monochlorosilane-based surface active materials, whose
lower alkyl groups are substituted, or dichlorosilane-based surface
active materials including
[0072]
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCl.sub.n(CH.sub.3).sub.3--
n,
[0073]
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2SiCl.sub.n(C.sub.2H.sub.5).-
sub.3-n,
[0074]
CF.sub.3CH.sub.2O(CH.sub.2).sub.15SiCl.sub.n(CH.sub.3).sub.3-n,
[0075]
CF.sub.3CH.sub.2O(CH.sub.2).sub.15SiCl.sub.n(C.sub.2H.sub.5).sub.3--
n,
[0076]
CF.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15SiCl.sub-
.n(CH.sub.3).sub.3-n,
[0077]
CF.sub.3(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2).sub.15SiCl.sub-
.n(C.sub.2H.sub.5).sub.3-n,
[0078]
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2-
).sub.9SiCl.sub.n(CH.sub.3).sub.3-n,
[0079]
CF.sub.3(CF.sub.2).sub.7(CH.sub.2).sub.2Si(CH.sub.3).sub.2(CH.sub.2-
).sub.9SiCl.sub.n(C.sub.2H.sub.5).sub.3-n,
[0080]
CF.sub.3COO(CH.sub.2).sub.15SiCl.sub.n(CH.sub.3).sub.3-n,
[0081] CF.sub.3COO(CH.sub.2).sub.15SiCln
(C.sub.2H.sub.5).sub.3-n,
[0082]
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2SiCl.sub.n(CH.sub.3).sub.3--
n, or
[0083]
CF.sub.3(CF.sub.2).sub.5(CH.sub.2).sub.2SiCl.sub.n(C.sub.2H.sub.5).-
sub.3-n,
[0084] where n represents 1 or 2.
[0085] In particular, trichlorosilane-based surface active
materials, in which adjacent molecules form siloxane bonds, are
preferable for obtaining a stronger chemically adsorbed film.
[0086] Moreover, CF.sub.3(CF.sub.2) CH.sub.2CH.sub.2SiCl.sub.3
(where n represents an integer, preferably between about 3 and 25)
is preferable since it is balanced with the dissolution property,
chemical adsorption property, water- and oil-repelling property,
and anticontamination property or the like. By incorporating an
unsaturated bond into an alkyl or alkyl fluoride chain, a bridge
formation can be formed by irradiation with an electron beam at
only about 5 Mrads, after formation of a chemically adsorbed film;
as a result, the hardness of the film can be improved.
[0087] Trichlorosilane-based surface active materials, such as the
following: CH.sub.3(CH.sub.2).sub.18SiCl.sub.3,
CH.sub.3(CH.sub.2).sub.15- SiCl.sub.3,
CH.sub.3(CH.sub.2).sub.10SiCl.sub.3) CH.sub.3(CH.sub.2).sub.25-
SiCl.sub.3 or the like, and monochlorosilane-based materials, whose
lower alkyl groups are substituted, or dichlorosilane-based surface
active materials, such as the folowing:
CH.sub.3(CH.sub.2).sub.18SiCl.sub.n(CH.s- ub.3).sub.3-n,
CH.sub.3(CH.sub.2).sub.18SiCl.sub.n(C.sub.2H.sub.5).sub.3-n- ,
CH.sub.3(CH.sub.2).sub.15SiCl.sub.n(CH.sub.3).sub.3-n,
CH.sub.3(CH.sub.2).sub.10SiCl.sub.n(CH.sub.3).sub.3-n,
CH.sub.3(CH.sub.2).sub.25SiCl.sub.n(C.sub.2H.sub.5).sub.3-n or the
like, are included as chlorosilane-based surface active materials
containing alkyl groups. CH.sub.3(CH.sub.2).sub.nSiCl.sub.3 (where
n represents an integer, preferably between about 3 and 25) is most
preferable among these for the dissolution property of the
solvent.
[0088] In order to achive a high adsorption density, a linear
chlorosilane-based surface active material is preferred. However,
as said active material applied in this invention, the alkyl
fluoride or hydrocarbon groups of the material can be diverged, or
the silicons at the ends of the material can be substituted by
alkyl fluoride or hydrocarbon groups, expressed as the formulas
including R.sup.2SiCl.sub.2, R.sup.3SiCl, R.sup.1R.sup.2SiCl.sub.2
or R.sup.1R.sup.2R.sup.3SiCl, where R, R.sup.1, R.sup.2 and R.sup.3
represent alkyl fluoride or hydroxyl groups.
[0089] A nonaqueous solvent used for this invention is preferably
chosen from the following solvents:
[0090] fluoric solvent such as 1,1-dichloro, 1-fluoroethane;
1,1-dichloro, 2,2,2-trifluoroethane; 1,1-dichloro,
2,2,3,3,3-pentafluoropropane; 1,3-dichloro,
1,1,2,2,3-heptafluoropropane or the like;
[0091] hydrocarbon-based solvent such as hexane, octane,
hexadecane, cyclohexane or the like;
[0092] ethers solvent such as dibutylether, dibenzylether or the
like;
[0093] esters solvent such as methyl acetate, ethyl acetate,
isopropyl acetate, amyl acetate or the like.
[0094] Acetone, methyl ethyl ketone or the like can be used as
ketones solvent.
[0095] Metal such as Al, Cu, stainless steel or the like, glass,
ceramics, or a group which is hydrophilic but contains a
comparatively small number of hydroxyl groups (--OH)--such as a
plastic, whose surface is hydrophilic--are included as groups which
can be used for this invention.
[0096] In employing metal as said group, it is preferable to use a
base metal such as Al, Cu or stainless steel since chemical
adsorption is promoted between the hydrophilic groups on the
substrate surface and chlorosilyl groups in this invention.
[0097] If a material, such as plastic, does not have an oxide film
on its surface, the surface must become hydrophilic beforehand by
introducing to it carboxyl and hydroxyl groups. The introduction of
such groups can be directed by treating the surface.with 100 W
under a plasma atmosphere, containing oxygen, for 20 minutes, or by
corona treatment. However, in case of nylon and polyurethane resin,
which have imino groups (>NH) on their surfaces, such treatment
is not necessary; a dehydrochlorination reaction is promoted
between the hydrogens of the imino groups (>NH) of the substrate
and the chlorosilyl groups (--SiCl) of a chemical adsorbent,
thereby creating a siloxane bond (--SiO--).
[0098] This invention can be applicable for various uses and
materials as described in the following:
[0099] (a) examples of substrates--metal, ceramics, plastic, wood,
stone (the invention being applicable even when the substrate
surface being coated with paint or the like in advance);
[0100] (b) examples of cutlery--kitchen and other knives, scissors,
engraver, razor blade, hair clippers, saw, plane, chisel, gimlet,
badkin, cutting tools, drill tip, blender blade, juicer blade,
flour mill blade, lawn mower blade, punch, straw cutter, stapler,
blade for can opener, surgical knife or the like;
[0101] (c) examples of needles--acupuncture needle, sewing needle,
sewing-machine needle, long thick needle for making tatami, syringe
needle, surgical needle, safety pin or the like;
[0102] (d) examples of products in the pottery industry--products
made of pottery, glass, ceramics or enameled products, including
hygienic potteries (such as a chamber pot, wash-bowl, bathtub,
etc.), tableware (such as a rice bowl, plate, bowl, teacup, glass,
bottle, coffee-pot, pots and pans, earthenware mortar, cup, etc.),
flower vases (such as a flower bowl, flowerpot, small flower vase,
etc.), water tanks (such as a breeding cistern, aquarium water
tank, etc.), chemistry apparatus (such as a beaker, reacter vessel,
test tube, flask, culture dish, condenser, stirring rod, stirrer,
mortar, vat, syringe), roof tile, tile, enameled tableware,
enameled wash bowl, and enameled pots and pans;
[0103] (e) examples of mirrors--hand mirror, full-length mirror,
bathroom mirror, washroom mirror, mirrors for automobile (back and
side mirrors), half mirror, mirror for show window, mirrors for
department store or the like;
[0104] (f) examples of molding parts--die for press molding, die
for cast molding, die for injection molding, die for transfer
molding, die for vacuum molding, die for blow forming, die for
extrusion molding, die for inflation molding, die for fiber
spinning, calender processing roll;
[0105] (g) examples of ornaments--watch, jewelry, pearl, sapphire,
ruby, emerald, garnet, cat's-eye, diamond, topaz, bloodstone,
aquamarine, turquoise, agate, marble, amethyst, cameo, opal,
crystal, glass, ring, bracelet, brooch, tiepin, earrings, necklace,
glasses frames (of platinum, gold, silver, aluminium, titanium,
tin, compound metals of these elements, or stainless steel) or the
like;
[0106] (h) examples of molds for food--cake mold, cookie mold,
bread mold, chocolate mold, jelly mold, ice cream mold, oven plate,
ice tray or the like;
[0107] (i) examples of cookware--pots and pans, iron pot, kettle,
pot, frying pan, hot plate, net for grilling food, tool for
draining off oil, plate for making takoyaki or the like;
[0108] (j) examples of paper--photogravure paper, water and oil
repellent paper, paper for posters, high-quality paper for
pamphlets or the like;
[0109] (k) examples of resin--polyolefin (such as polypropylene,
polyethylene, etc.), polyvinylchloride, polyvinylidenechloride,
polyamide, polyimide, polyamideimide, polyester, aromatic
polyester, polystyrene, polysulfone, polyethersulfone,
polyphenylenesulfide, phenolic resin, furan resin, urea resin,
epoxide, polyurethane, silicon resin, ABS resin, methacrylic resin,
ethylacrylate resin, ester resin, polyacetal, polyphenyleneoxide or
the like;
[0110] (l) examples of household electric goods--television, radio,
tape recorder, audio goods, CD player, refrigerator, freezer, air
conditioner, juicer, blender, blade of an electric fan, lighting
equipment, dial plate, hair drier for perm or the like;
[0111] (m) examples of sporting goods--skis, fishing rod, pole for
pole vault, boat, sailboat, jet skis, surfboard, golf ball, bowling
ball, fishing line, fishing net, fishing float or the like;
[0112] (n) examples of vehicle parts;
[0113] (1) ABS resin--lamp cover, instrument panel, trimming parts,
and protector for a motorcycle,
[0114] (2) cellulose plastic--markings for automobile, and steering
wheel,
[0115] (3) FRP (Fiber Reinforced Plastics)--bumper, and engine
cover,
[0116] (4) phenolic resin--brake,
[0117] (5) polyacetal--wiper, wiper gear, gas valve, carburetor
parts,
[0118] (6) polyamide--radiator fan,
[0119] (7) polyarylate (polycondensation polymerization by
bisphenol A and pseudo phthalic acid)--direction indicator lamp (or
lens), cowl board lens, relay case,
[0120] (8) polybutylene terephthalate--rear end, front fender,
[0121] (9) poly amino-bismaleimide--engine parts, gear box, wheel,
suspension drive system,
[0122] (10) methacrylate resin--lamp cover lens, meter panel and
cover, and center mark,
[0123] (11) polypropylene--bumper,
[0124] (12) polyphenylene oxide--radiator grill, wheel cap,
[0125] (13) polyurethane--bumper, fender, instrument panel, and
fan,
[0126] (14) unsaturated polyester resin--body, gas tank, heater
housing, meter panel,
[0127] (o) examples of stationary goods--fountain pen, ballpoint
pen, mechanical pencil, pencil case, binder, desk, chair, book
shelf, rack, telephone base, ruler, draftsman's outfit or the
like;
[0128] (p) examples of building materials--roof materials (such as
ceramic tile, slate, tin such as used in galvanized iron plate,
etc.), outer wall materials (such as wood including processed wood,
mortar, concrete, ceramic sizing, metallic sizing, brick, building
stone, plastic material, metallic material including aluminium,
etc.), interior materials (such as wood including processed wood,
metallic material including aluminium, plastic material, paper,
fiber, etc.) or the like;
[0129] (q) examples of stone materials--granite, marble or the
like, used for building, building material, works of art, ornament,
bath, gravestone, monument, gatepost, stone wall, sidewalk, paving
stone, etc.
[0130] (r) examples of musical instruments and audio
apparatus--percussion instruments, string instruments, keyboard
instruments, woodwind instruments, brass instruments or the like,
more specifically, drum, cymbals, violin, cello, guitar, koto,
piano, flute, clarinet, shakuhachi, horn, etc., and microphone,
speaker, earphone or the like.
[0131] (s) others--high voltage insulator with good water, oil and
contamination-repelling properties, including thermos bottles,
vacuum apparatus, insulator for transmitting electricity, spark
plugs or the like.
[0132] The method of manufacturing a chemically adsorbed film of
the invention will now be explained specifically in the following
examples 1-3.
EXAMPLE 1
[0133] Adsorption solution A was prepared by dissolving 1% by
weight of a chemical adsorbent, n-nonadecyl trichlorosilane, into
the mixed solvent of hexadecane, carbon tetrachloride and
chloroform at a weight ratio of 80:12:8 respectively.
[0134] Glass substrate 1, as a hydrophilic group, was prepared as
shown in FIG. 1. After being washed with a nonorganic solvent, the
substrate was dipped in adsorption solution A for five minutes. Due
to this treatment, a dehydrochlorination reaction was promoted
between the Si--Cl groups of n-nonadecyl trichlorosilane and the
--OH groups of glass substrate 1, thereby forming a chemically
adsorbed film on the substrate as shown in formula [1]. 1
[0135] A chemically adsorbed monomolecular film 2 as shown in FIG.
2, which had only a few horizontal bonds since the --OH groups were
unaffected, was formed after washing the substrate with a
nonorganic solvent for 15 minutes and with chloroform for another
15 minutes. This monomolecular film was firmly connected to the
substrate, and had excellent water-repelling properties.
[0136] The formation of the film was confirmed by obtaining
particular signals for this structure at 3680 (reversion: Si--OH),
2930-2840 (reversion: CH.sub.3, --CH.sub.2--), 1470 (reversion:
--CH.sub.2--), and 1080 (reversion: Si--O)cm.sup.-1 by Fourier
Transform Infrared Spectral (FTIR) measurement.
[0137] As a next step, a readsorption reaction was directed. The
substrate with the formed monomolecular film was dipped and held in
a newly prepared adsorption solution A for one hour. The substrate
was then washed with a nonorganic solvent for 15 minutes and with
water for another 15 minutes, thereby promoting a
dehydrochlorination reaction between Si--Cl groups of n-nonadecyl
trichlorosilane and --OH groups at the root of monomolecular film
3. As a result, a chemically adsorbed film was formed on glass
substrate 1 as shown in FIG. 3.
[0138] According to FTIR measurement, the particular signals for
this structure at 2930-2840 (reversion: CH.sub.3, --CH.sub.2--),
1470 (reversion: --CH.sub.2--), 1080 (reversion: Si--O)cm.sup.-1
were stronger than the signals obtained after the first reaction.
This result confirmed the increase of admolecules. The absorption
wave number, measuring the asymmetric stretching vibration of
methylene, declined from 2929 cm.sup.-1 after the first adsorption
reaction to 2921 cm.sup.-1 after the second reaction. It is
generally known that such decline in wave number occurs when the
distance between molecules with a long chain alkyl part decreases.
In fact, the absorption wave number of certain material decreases
as the material changes from a gaseous body to a liquid body and
then to a solid body. Therefore, confirmation was obtained that the
film density increased due to the decrease in distance between the
molecules--the composition of the film--after the readsorption
reaction.
EXAMPLE 2
[0139] Adsorption solution B was prepared by dissolving 1% by
weight of a chemical adsorbent, n-nonadecenyl trichlorosilane, into
a mixed solvent of hexadecane, carbon tetrachloride and chloroform
at a weight ratio of 80:12:8, respectively. As a hydrophilic group,
glass substrate 1 was prepared. After being washed with organic
solvent, the substrate was dipped and held in adsorption solution B
for five minutes. As a result, a dehydrochlorination reaction was
promoted between Si--Cl of n-nonadecenyl trichlorosilane and OH of
glass substrate 1, thereby forming a chemically adsorbed film on
the substrate as shown in formula [2]. 2
[0140] After washing the substrate with a nonaqueous solvent for 15
minutes and with chloroform for another 15 minutes, chemically
adsorbed monomolecular film 5 as shown in FIG. 4, which had few
horizontal bonds since --OH groups were unaffected, was formed.
This monomolecular film was firmly connected to the substrate, and
possessed good water-repelling properties.
[0141] Signals were obtained for this structure at 2930-2840
(reversion: --CH.sub.2--), 1470 (reversion: --CH.sub.2--), 1080
(reversion: Si--O)cm.sup.-1 by FTIR measurement, thereby confirming
the formation of the film.
[0142] A readsorption reaction was directed as in the following
procedures:
[0143] dipping and holding the substrate formed with the
monomolecular film in a newly prepared adsorption solution B;
[0144] washing the substrate with a nonaqueous solvent for 15
minutes and with water for another 15 minutes.
[0145] A dehydrochlorination reaction was then promoted between
Si--Cl of n-nonadecyl trichlorosilane and --OH groups of glass
substrate 1, thereby forming a chemically adsorbed film on the
substrate as shown in FIG. 5.
[0146] The particular signals obtained by FTIR measurement at
2930-2840 (reversion: --CH.sub.2--), 1470 (reversion:
--CH.sub.2--), 1080 (reversion: Si--O)cm.sup.-1 for this structure
were strengthened compared with the signals obtained from the first
adsorption reaction, thereby confirming an increase of admolecules.
Moreover, the absorption wave number of assymmetric stretching
vibration of methylene declined from 2928 cm.sup.-1 after the first
adsorption to 2921 cm.sup.-1 after the second adsorption.
[0147] As in example 1, after the readsorption reaction, the
distance between molecules of the film became shorter, and the film
density was increased.
EXAMPLE 3
[0148] Adsorption solution C was prepared by dissolving 1% by
weight of a chemical adsorbent, 14-bromotetradecyl trichlorosilane,
into a mixed solvent of hexadecane, carbon tetrachloride and
chloroform at a weight ratio of 80:12:8, respectively.
[0149] A chemically adsorbed film shown in FIG. 2 was formed
through the following procedures as detailed in example 2:
[0150] promoting the first adsorption by dipping and holding glass
substrate 1 in adsorption solution A;
[0151] washing the substrate with a nonaqueous solution,
chloroform, and then with water, thereby forming the film. This
monomolecular film was firmly fixed to the substrate, and had a
good water-repelling property. As in example 1, the formation of
the film was confirmed by obtaining particular signals by FTIR
measurement.
[0152] Readsorption was directed as in the following
procedures:
[0153] dipping and holding the substrate formed with monomolecular
film 3 in a newly prepared adsorption solution C for one hour;
[0154] washing the substrate with a nonaqueous solvent for 15
minutes and with chloroform for another 15 minutes.
[0155] As a result, a dehydrochlorination reaction was promoted
between Si--Cl of 14-bromotetradecyl trichlorosilane and OH of
glass substrate 1 or at the root of monomolecular film 3, thereby
forming chemically adsorbed film 7 on the substrate as shown in
FIG. 6.
[0156] Stronger signals at 2930-2840 (reversion: CH.sub.3,
--CH.sub.2--), 1470 (reversion: --CH.sub.2--), 1080 (reversion:
Si--O)cm.sup.-1 were obtained by FTIR measurement after the second
adsorption reaction. The creation of an additional particular
signal at 1440 (reversion: Br--C)cm.sup.-1 was also confirmed after
the second adsorption. Absorption wave number by the asymmetric
stretching vibration of methylene declined from 2928 cm.sup.-1
after the first adsorption to 2922 cm.sup.-1 after the second
adsorption. As in other examples, it was confirmed that the
distance between the molecules became shorter and the film density
was increased.
[0157] Although a chemical adsorbent containing halosilyl groups
was used for examples 1-3, the same results could be obtained by
using an adsorbent having alkoxysilyl groups or the like.
[0158] For the first adsorption reaction, a chemical adsorbent
comprises a functional group shown in formula [A] or formula [B].
From the second repetition onwards, however, a chemical adsorbent
contains at least one group chosen from the group consisting of
halosilyl, alkoxysilyl or functional groups shown in formulas [A]
through [G].
[0159] As explained above, a highly dense chemically adsorbed film
is formed by repeating an adsorption reaction and washing process,
and by covalently bonding a chemical adsorbent to a substrate and a
chemically adsorbed film. The density of the adsorbed film, in
addition, can be controlled by varying the time for adsorption
reaction, the number of repetitions, and the kind and combination
of chemical adsorbents.
[0160] The invention may be embodied in other specific forms
without departing from the spirit or essential characteristics
thereof. The present embodiment is to be considered in all respects
as illustrative and not restrictive, 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.
* * * * *