U.S. patent application number 12/523591 was filed with the patent office on 2010-02-25 for composition and dental material.
This patent application is currently assigned to Kuraray Medical Inc.. Invention is credited to Ai Hinamoto, Hiroshige Ishino, Naoki Nishigaki, Koichi Okada, Takahiro Sekiguchi, Mariko Sugiura.
Application Number | 20100048762 12/523591 |
Document ID | / |
Family ID | 39635983 |
Filed Date | 2010-02-25 |
United States Patent
Application |
20100048762 |
Kind Code |
A1 |
Ishino; Hiroshige ; et
al. |
February 25, 2010 |
COMPOSITION AND DENTAL MATERIAL
Abstract
The present invention provides a composition that exhibits
excellent adhesive properties to tooth structure (particularly
dentin) when applied as a dental material. The present invention is
a composition containing a polymerizable monomer (A) having an
unconjugated carbon chain with at least four carbon atoms bonded
continuously, at least two polymerizable groups, and at least two
hydroxyl groups, and a bisacylphosphine oxide (B) represented by
the following formula (1): ##STR00001## where the respective
symbols are as defined in the specification.
Inventors: |
Ishino; Hiroshige; (Okayama,
JP) ; Sekiguchi; Takahiro; (Okayama, JP) ;
Okada; Koichi; (Okayama, JP) ; Nishigaki; Naoki;
(Okayama, JP) ; Hinamoto; Ai; (Okayama, JP)
; Sugiura; Mariko; (Okayama, JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, L.L.P.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
Kuraray Medical Inc.
Kurashiki-shi
JP
|
Family ID: |
39635983 |
Appl. No.: |
12/523591 |
Filed: |
January 16, 2008 |
PCT Filed: |
January 16, 2008 |
PCT NO: |
PCT/JP08/50439 |
371 Date: |
October 23, 2009 |
Current U.S.
Class: |
523/116 |
Current CPC
Class: |
A61K 6/30 20200101; A61K
6/30 20200101; C08F 20/10 20130101; A61K 6/30 20200101; A61K 6/887
20200101; A61K 6/30 20200101; A61K 6/887 20200101; A61K 6/887
20200101; C08F 20/28 20130101; A61K 6/30 20200101; C08L 33/04
20130101; C08F 220/26 20130101; C08L 33/04 20130101; C08L 33/26
20130101; C08L 33/04 20130101; C08L 33/04 20130101; C08L 33/26
20130101; C08L 33/26 20130101; C08L 33/26 20130101; A61K 6/887
20200101; A61K 6/887 20200101 |
Class at
Publication: |
523/116 |
International
Class: |
A61K 6/087 20060101
A61K006/087 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 17, 2007 |
JP |
2007-008420 |
Jan 17, 2007 |
JP |
2007-008421 |
Mar 20, 2007 |
JP |
2007-073603 |
Claims
1. A composition comprising a polymerizable monomer (A) having an
unconjugated carbon chain with at least four carbon atoms bonded
continuously, at least two polymerizable groups, and at least two
hydroxyl groups, and a bisacylphosphine oxide (B) represented by
formula (1): ##STR00016## in which R.sup.4 indicates an alkyl
group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy
group, an acyl group, or an acyloxy group, and R.sup.5 to R.sup.14
are each independently a hydrogen atom, a halogen atom, an alkyl
group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy
group, an acyl group, or an acyloxy group.
2. The composition according to claim 1, wherein the polymerizable
monomer (A) has a group represented by formula (2): ##STR00017## in
which G is a hydroxyl group or a polymerizable group and "*"
indicates a bond.
3. The composition according to claim 1, wherein the polymerizable
groups each are a group represented by formula (3), formula (4), or
formula (5): ##STR00018## in which R.sup.1, R.sup.2, and R.sup.3
each indicate a hydrogen atom or an aliphatic hydrocarbon group
having 1 to 10 carbon atoms and "*" indicates a bond.
4. The composition according to claim 1, wherein the polymerizable
monomer (A) is a compound represented by formula (6): ##STR00019##
in which the Gs are hydroxyl groups or polymerizable groups, n is
an integer of 2 or more, at least two of the Gs are hydroxyl
groups, and at least two of the Gs are polymerizable groups.
5. The composition according to claim 1, wherein the polymerizable
monomer (A) is a compound represented by formula (7): ##STR00020##
in which R.sup.1 denotes a hydrogen atom or an aliphatic
hydrocarbon group having 1 to 10 carbon atoms, m denotes an integer
of 2 or more, k denotes an integer of 1 or more, and the sequence
order of m units having an ester group and k units having a
hydroxyl group is arbitrary.
6. The composition according to claim 5, wherein m is 2 to 5 and k
is 1 to 5.
7. The composition according to claim 1, wherein the polymerizable
monomer (A) is a compound represented by formula (8): ##STR00021##
in which R.sup.1 denotes a hydrogen atom or an aliphatic
hydrocarbon group having 1 to 10 carbon atoms and p denotes an
integer of 2 or more.
8. The composition according to claim 7, wherein p is 2 to 4.
9. The composition according to claim 3, wherein R.sup.1 is a
hydrogen atom or a methyl group.
10. The composition according to claim 1, wherein R.sup.4 is an
alkyl group or an aryl group, and R.sup.5 to R.sup.14 are each
independently a hydrogen atom, a halogen atom, an alkyl group, or
an alkoxy group.
11. The composition according to claim 1, further comprising, as a
polymerizable monomer component, at least one polymerizable monomer
selected from the group consisting of a polymerizable monomer (C)
having one polymerizable functional group and at least one hydroxyl
group, a polymerizable monomer (D) having an acidic group, and a
crosslinkable polymerizable monomer (E).
12. The composition according to claim 1, comprising a solvent
(F).
13. The composition according to claim 1, further comprising at
least one polymerization initiator (G) selected from the group
consisting of acylphosphine oxides, water-soluble acylphosphine
oxides, thioxanthones, quaternary ammonium salts of thioxanthones,
ketals, alpha-diketones, coumarins, anthraquinones, benzoin alkyl
ether compounds, alpha-amino ketone compounds, and organic
peroxides and/or polymerization accelerator (H).
14. (canceled)
15. The composition according to claim 1, comprising a filler
(I).
16. The composition according to claim 1, wherein 0.01 to 20 parts
by mass of the bisacylphosphine oxide (B) is contained with respect
to 100 parts by mass of the whole amount of polymerizable monomer
components.
17. A dental application composition comprising the composition
according to claim 1.
18. A primer comprising the composition according to claim 17.
19. A bonding material comprising the composition according to
claim 17.
20. A composite resin comprising the composition according to claim
17.
21. A cement comprising the composition according to claim 17.
Description
TECHNICAL FIELD
[0001] The present invention relates to compositions that are
particularly suitable for dental materials and that contain
polymerizable monomers and polymerization initiators. The present
invention also relates to dental materials using the compositions,
such as dental primers, bonding materials, composite resins, and
cements.
BACKGROUND ART
[0002] When a lost part of a tooth is filled or covered with a
restorative material, generally a dental adhesive is used. A known
dental adhesive is one containing a polymerizable monomer having a
polymerizable group and a hydroxyl group. For example, WO
2004/047773 describes a dental adhesive composition characterized
by containing a polyfunctional polymerizable monomer that is an
ester compound of polyhydric alcohol having 3 to 6 carbon atoms and
a plurality of (meth)acrylic acids and that has one to two hydroxyl
groups, a monofunctional (meth)acrylate having no hydroxyl group in
the molecule, a polymerizable monomer having an acidic group in the
molecule, an organoboron compound as a curing agent, and a filling
material. This describes that the addition of a small amount of the
above polyfunctional polymerizable monomer to the composition can
improve the cure rate considerably almost without affecting the
adhesive properties of the composition, physical properties of the
cured product, or operable time. Recently, however, higher bond
strength to a tooth structure is desired, and therefore there may
be a problem in bond strength in some cases.
[0003] When such a dental adhesive is allowed to act on dentin, it
is important for the dental adhesive to have an decalcifying effect
that allows a dentin surface to be dissolved with an acidic
component, a penetration effect that allows a monomer component to
penetrate into a collagen layer of dentin, and a curing effect that
allows the monomer component thus penetrated to solidify to form a
hybrid layer (hereinafter also referred to as a "resin-impregnated
layer") with collagen.
[0004] It has been studied so far to simplify the form of
application of the dental adhesive from a three-component
three-step type in which the aforementioned decalcifying effect,
penetration effect, and curing effect are applied sequentially, to
a two-component two-step type in which the decalcifying effect and
the penetration effect are integrated, and further to a
one-component one-step type in which the decalcifying effect,
penetration effect, and curing effect are all combined together.
All the forms of application require compositions that can be used
for dental adhesives that are excellent in adhesive properties.
DISCLOSURE OF INVENTION
[0005] The present invention is intended to provide a composition
that exhibits excellent adhesive properties to a tooth structure
(particularly dentin) when it is applied as a dental material. The
present invention also is intended to provide a dental material
that is excellent in adhesive properties to a tooth structure
(particularly dentin).
[0006] The present invention that has achieved the above-mentioned
objects is a composition including a polymerizable monomer (A)
having an unconjugated carbon chain with at least four carbon atoms
bonded continuously, at least two polymerizable groups, and at
least two hydroxyl groups, and a bisacylphosphine oxide (B)
represented by formula (1):
##STR00002##
[0007] where R.sup.4 indicates an alkyl group, alkenyl group,
alkynyl group, aryl group, alkoxy group, acyl group, or acyloxy
group, and R.sup.5 to R.sup.14 are each independently a hydrogen
atom, halogen atom, alkyl group, alkenyl group, alkynyl group, aryl
group, alkoxy group, acyl group, or acyloxy group.
[0008] Preferably, the polymerizable monomer (A) includes a group
represented by formula (2):
##STR00003##
[0009] where G is a hydroxyl group or polymerizable group and "*"
indicates a bond.
[0010] Preferably, the polymerizable groups each are a group
represented by formula (3), (4), or (5):
##STR00004##
[0011] where R.sup.1 indicates a hydrogen atom or an aliphatic
hydrocarbon group having 1 to 10 carbon atoms and "*" indicates a
bond.
[0012] Preferably, the polymerizable monomer (A) is a compound
represented by formula (6):
##STR00005##
[0013] where Gs are hydroxyl groups or polymerizable groups, n is
an integer of 2 or more, at least two of the Gs are hydroxyl
groups, and at least two of the Gs are polymerizable groups. An
example of more preferable polymerizable monomers (A) is a compound
represented by formula (7):
##STR00006##
[0014] where R.sup.1 denotes a hydrogen atom or an aliphatic
hydrocarbon group having 1 to 10 carbon atoms, m denotes an integer
of 2 or more, k denotes an integer of 1 or more, and the sequence
order of m units having an ester group and k units having a
hydroxyl group is arbitrary. In this case, it is preferable that m
be 2 to 5 and k be 1 to 5.
[0015] Another example of more preferable polymerizable monomers
(A) is a compound represented by formula (8):
##STR00007##
where R.sup.1 denotes a hydrogen atom or an aliphatic hydrocarbon
group having 1 to 10 carbon atoms and p denotes an integer of 2 or
more. In this case, it is preferable that p be 2 to 4.
[0016] In the above, it is preferable that R.sup.1 be a hydrogen
atom or methyl group.
[0017] With respect to the bisacylphosphine oxide (B), it is
preferable that R.sup.4 be an alkyl group or aryl group, and
R.sup.5 to R.sup.14 be each independently a hydrogen atom, halogen
atom, alkyl group, or alkoxy group.
[0018] Preferably, depending on the embodiment, the composition of
the present invention further includes, as a polymerizable monomer
component, at least one polymerizable monomer selected from the
group consisting of a polymerizable monomer (C) having one
polymerizable functional group and at least one hydroxyl group, a
polymerizable monomer (D) having an acidic group, and a
crosslinkable polymerizable monomer (E). Furthermore, preferably,
depending on the embodiment, the composition of the present
invention includes at least one selected from the group consisting
of a solvent (F), a polymerization accelerator (H), and a filler
(I). Moreover, preferably, the composition of the present invention
further includes at least one polymerization initiator (G) selected
from the group consisting of acylphosphine oxides, water-soluble
acylphosphine oxides, thioxanthones, quaternary ammonium salts of
thioxanthones, ketals, alpha-diketones, coumarins, anthraquinones,
benzoin alkyl ether compounds, alpha-amino ketone compounds, and
organic peroxides.
[0019] Preferably, the composition of the present invention
contains 0.01 to 20 parts by mass of bisacylphosphine oxide (B)
with respect to 100 parts by mass of the whole amount of polymer
monomer components.
[0020] The composition of the present invention is suitable for
dental applications.
[0021] Furthermore, the present invention includes a dental primer,
dental bonding material, dental composite resin, and dental cement,
each of which contains the above-mentioned composition.
[0022] Since the composition of the present invention contains a
polymerizable monomer having a plurality of polymerizable groups
and hydrophilic groups as well as a polymerization initiator having
excellent performance, it is useful for the applications that
require curability and those that require hydrophilicity and it is
particularly suitable for dental applications. Dental materials
(such as a dental primer, bonding material, composite resin, and
cement) using the compositions of the present invention exhibit
excellent curability and are exceptionally excellent in adhesive
properties to tooth structures.
BEST MODE FOR CARRYING OUT THE INVENTION
[0023] First, essential components of the composition of the
present invention are described.
[0024] Polymerizable Monomer (A)
[0025] The polymerizable monomer (A) has an unconjugated carbon
chain with at least four carbon atoms bonded continuously, at least
two polymerizable groups, and at least two hydroxyl groups. For the
polymerizable monomer (A), polymerizable monomers that satisfy such
a definition can be used independently or two or more of them can
be used in combination.
[0026] The polymerizable monomer (A) has at least two polymerizable
groups. When a composition of the present invention is used for a
dental application, these polymerizable groups are polymerized and
thereby the composition is cured to be able to function as, for
example, a primer, bonding material, composite resin, or cement.
Furthermore, since the number of the polymerizable groups is two or
more, the polymerizable monomer (A) has crosslinkability.
Accordingly, the composition has high curability and the cured
product has high mechanical strength.
[0027] With respect to the polymerizable monomer (A), the
polymerizable group denotes a group including a radical
polymerizable functional group and examples thereof include a group
including a vinyl group. Particularly, from the viewpoint of
polymerization reactivity, the group represented by the following
formula (3), (4), or (5) is preferable as the polymerizable group.
Among these, from the viewpoint of ease of introduction into the
polymerizable monomer (A), a group represented by formula (3) is
most preferable.
##STR00008##
[0028] In the above formulae, R.sup.1, R.sup.2, and R.sup.3 each
indicate a hydrogen atom or an aliphatic hydrocarbon group having 1
to 10 carbon atoms and "*" indicates a bond. Examples of the
aliphatic hydrocarbon group having 1 to 10 carbon atoms include an
alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2
to 10 carbon atoms, and an alkynyl group having 2 to 10 carbon
atoms.
[0029] The alkyl group having 1 to 10 carbon atoms may be any one
of linear, branched, and cyclic, and examples thereof include a
methyl group, ethyl group, n-propyl group, isopropyl group,
cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group,
tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl
group, neopentyl group, tert-pentyl group, cyclopentyl group,
n-hexyl group, isohexyl group, cyclohexyl group, n-heptyl group,
cycloheptanyl group, n-octyl group, 2-ethylhexyl group,
cyclooctanyl group, n-nonyl group, cyclononanyl group, and n-decyl
group.
[0030] The alkenyl group having 2 to 10 carbon atoms may be any one
of linear, branched, and cyclic, and examples thereof include a
vinyl group, allyl group, methylvinyl group, propenyl group,
butenyl group, pentenyl group, hexenyl group, cyclopropenyl group,
cyclobutenyl group, cyclopentenyl group, and cyclohexenyl
group.
[0031] The alkynyl group having 2 to 10 carbon atoms may be any one
of linear, branched, and cyclic, and examples thereof include
ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 1-methyl-2-propynyl,
2-butynyl, 3-butynyl, 1-pentynyl, 1-ethyl-2-propynyl, 2-pentynyl,
3-pentynyl, 1-methyl-2-butynyl, 4-pentynyl, 1-methyl-3-butynyl,
2-methyl-3-butynyl, 1-hexynyl, 2-hexynyl, 1-ethyl-2-butynyl,
3-hexynyl, 1-methyl-2-pentynyl, 1-methyl-3-pentynyl,
4-methyl-1-pentynyl, 3-methyl-1-pentynyl, 5-hexynyl, and
1-ethyl-3-butynyl.
[0032] When the polymerizable monomer (A) is used in, for example,
dental applications, radical polymerization is performed.
Accordingly, it is preferable from the viewpoint of radical
polymerization reactivity of the final product that R.sup.1,
R.sup.2, and R.sup.3 each be a hydrogen atom or a methyl group.
Furthermore, when the polymerizable monomer (A) is used in a dental
composition, the polymerizable group may be detached from the
polymerizable monomer (A) by, for example, hydrolysis. When the
stimulativeness of the detached polymerizable group to a biological
body is taken into account, it is preferable that the polymerizable
group include a methacryloyloxy group. Therefore, it is more
preferable that R.sup.1, R.sup.2, and R.sup.3 each be a methyl
group.
[0033] The polymerizable monomer (A) includes at least two
polymerizable groups, and the at least two polymerizable groups may
be identical to or different from each other.
[0034] The polymerizable monomer (A) has at least two hydroxyl
groups. These hydroxyl groups allow the polymerizable monomer (A)
to be provided with high hydrophilicity to have high penetrability
into a collagen layer of dentin, which results in high adhesive
properties of the composition to a tooth structure.
[0035] The polymerizable monomer (A) has an unconjugated carbon
chain with at least four carbon atoms bonded continuously.
Preferably, this carbon chain composes the whole or a part of the
skeleton of the polymerizable monomer (A), and the polymerizable
groups and hydroxyl groups are bonded to the carbon chain.
[0036] An example of the polymerizable monomer (A) is a compound in
which a part of hydroxyl groups of a tetravalent or more alcohol
compound having an unconjugated carbon chain with at least four
carbon atoms bonded continuously is substituted by polymerizable
groups so that the number of each of the hydroxyl groups and the
polymerizable groups is two or more. Examples of the tetravalent or
more alcohol compound having an unconjugated carbon chain with at
least four carbon atoms bonded continuously are not particularly
limited. Preferable examples thereof include sugar alcohol,
monosaccharides, disaccharides, and trisaccharides, each of which
has 4 to 20 carbon atoms. Examples of the sugar alcohol that is
used preferably include erythritol, a sugar alcohol having 4 carbon
atoms, xylitol, ribitol, and arabinitol, each of which is a sugar
alcohol having 5 carbon atoms, mannitol, sorbitol, and iditol, each
of which is a sugar alcohol having 6 carbon atoms, and maltitol, a
sugar alcohol having 12 carbon atoms. Furthermore, glucamine, a
sugar alcohol containing an amino group, also is used preferably.
Examples of monosaccharides that are used preferably include
xylose, ribose, arabinose, and lyxose, each of which is a
monosaccharide having 5 carbon atoms, as well as glucose, mannose,
galactose, sorbose, and fructose, each of which is a monosaccharide
having 6 carbon atoms. Furthermore, glucosamine, mannosamine,
galactosamine, N-acetylglucosamine, N-acetylmannosamine, and
N-acetylgalactosamine that are monosaccharides, each of which
contains an amino group and a derivative thereof, also are used
preferably. Examples of disaccharides that are used preferably
include trehalose, sucrose, maltose, lactose, and cellobiose.
Examples of trisaccharides that are used preferably include
Coupling Sugar (registered trademark), lactosucrose, maltotriose,
and isomaltotriose. The composition of the present invention is
used preferably as a dental composition and more preferably as a
dental adhesive composition. From the viewpoint of adhesive
properties to a tooth structure (particularly dentin), it is
preferable that it have high penetrability into the tooth structure
(particularly dentin). From such a viewpoint, the carbon number of
the aforementioned alcohol compound is more preferably 4 to 15,
further preferably 4 to 9, and particularly preferably 4 to 7.
Moreover, from the same viewpoint, the number of the hydroxyl
groups of the alcohol compound is preferably 4 to 15, more
preferably 4 to 9, and particularly preferably 4 to 7. Specific
examples of preferable alcohol compounds include: erythritol,
mannitol, sorbitol, and maltitol as sugar alcohols; glucose and
glucosamine as monosaccharides; trehalose and maltose as
disaccharides; and maltotriose as trisaccharides. Among these,
erythritol, mannitol, glucose, and trehalose are further preferable
and erythritol and mannitol are particularly preferable.
[0037] Preferably, the polymerizable monomer (A) has a group
represented by the following formula (2). This group is a structure
that is characteristic to the compounds indicated above as
examples.
##STR00009##
[0038] In the above formula, G indicates a hydroxyl group or
polymerizable group and "*" indicates a bond.
[0039] With respect to the structure of the polymerizable monomer
(A), specifically, the polymerizable monomer (A) is preferably a
compound represented by formula (6).
##STR00010##
[0040] In the above formula, Gs are hydroxyl groups or
polymerizable groups, n is an integer of 2 or more, at least two of
the Gs are hydroxyl groups, and at least two of the Gs are
polymerizable groups.
[0041] In this structure, the polymerizable group or the hydroxyl
group is bonded to each carbon atom of the carbon chain, and
therefore the polymerizable groups and hydroxyl groups are
closely-located with a high density. Accordingly, when a
composition containing this polymerizable monomer (A) is applied as
a dental material, it exhibits excellent curability and adhesive
properties. Furthermore, it also has an advantage that it can be
produced easily using sugar alcohol.
[0042] From the viewpoints of curability and adhesive properties to
a tooth structure of the composition as well as availability of raw
materials, n is preferably an integer of 2 to 18, more preferably
an integer of 2 to 9, and most preferably an integer of 2 to 4.
[0043] When adhesive properties to a tooth structure of the
composition is considered important, the polymerizable monomer (A)
is preferably a compound represented by the following formula
(7).
##STR00011##
[0044] In the above formula, R.sup.1 denotes the same as described
above, m denotes an integer of 2 or more, k denotes an integer of 1
or more, and the sequence order of m units having an ester group
and k units having a hydroxyl group is arbitrary.
[0045] From the viewpoints of curability and adhesive properties to
a tooth structure of the composition as well as availability of raw
materials, m is preferably 2 to 5, more preferably 2 to 4, and most
preferably 2. Furthermore, k is preferably 1 to 5, more preferably
2 to 4, and most preferably 2. The total of m and k is preferably 3
to 18, more preferably 3 to 9, further preferably 4 to 8, and most
preferably 4.
[0046] The compound represented by formula (7) has at least three
hydroxyl groups, two of which are primary hydroxyl groups. These
primary hydroxyl groups are highly advantageous for interaction
with a tooth structure (particularly dentin). Accordingly, when a
composition containing a compound represented by formula (7) is
applied as dental applications, a composition with particularly
high adhesive properties to a tooth structure (particularly dentin)
is obtained. Moreover, since at least two groups represented by
formula (3) are included as polymerizable groups, curability also
is excellent.
[0047] Furthermore, among the compounds represented by formula (7),
compounds represented by formulae (9) and (10) are preferable from
the viewpoints of curability and adhesive properties to a tooth
structure of the composition.
##STR00012##
[0048] On the other hand, when curability of the composition is
considered important, the polymerizable monomer (A) is preferably a
compound represented by the following formula (8).
##STR00013##
[0049] In the above formula, R.sup.1 denotes the same as described
above, and p denotes an integer of 2 or more.
[0050] The compound represented by formula (8) has polymerizable
groups represented by formula (3) at the both ends of an
unconjugated carbon chain with at least four carbon atoms bonded
continuously and has particularly high polymerization performance
due to a steric factor. Accordingly, when a composition containing
a compound represented by formula (8) is applied as a dental
application, it serves as a composition with particularly high
curability. Moreover, since it has a plurality of hydroxyl groups,
it has excellent penetrability into a collagen layer of dentin as
well as excellent adhesive properties to a tooth structure.
[0051] p is preferably 2 to 4. This is because when a decomposition
product is produced by an action such as hydrolysis inside an oral
cavity, the decomposition product is a highly safe compound such as
erythritol, xylitol, sorbitol, or mannitol. Examples of compounds
in which p is 2 to 4 include erythritol di(meth)acrylate, xylitol
di(meth)acrylate, and sorbitol di(meth)acrylate. Furthermore,
erythritol di(meth)acrylate in which p is 2 is more preferable, and
when the aforementioned viewpoints of polymerizability and
stimulativeness to a biological body also are taken into
consideration, erythritol dimethacrylate represented by the
following general formula (11) is most preferable.
##STR00014##
[0052] The polymerizable monomer (A) can be obtained through
production by a known method. Specifically, for example, a
carboxylic acid having a polymerizable group (for instance, a
carboxylic acid in which a hydrogen atom is bonded to a bond of a
group represented by formula (3)) or a derivative thereof and the
tetravalent or more alcohol compound having an unconjugated carbon
chain with at least four carbon atoms bonded continuously may be
allowed to undergo an esterification reaction according to a
conventional method and this may then be purified by a separation
means such as chromatography. In order to improve the yield, the
esterification reaction may be carried out after the carboxylic
acid having a polymerizable group is converted into a derivative
such as an acid halide.
[0053] When the polymerizable monomer (A) is particularly a
compound represented by formula (7), especially a compound
represented by formula (9) or (10), it is preferable that the
polymerizable monomer (A) be produced by performing a step (a)
where using a compound in which primary hydroxyl groups of the
alcohol compound are protected beforehand, as a raw material, the
compound and carboxylic acid having a polymerizable group (in this
case, carboxylic acid in which a hydrogen atom is bonded to a bond
of a group represented by formula (3)) or a derivative thereof are
esterified, and a step (b) where the protecting groups of the
primary hydroxyl groups of the resultant ester compound are
deprotected. The derivative of the carboxylic acid having a
polymerizable group is not particularly limited but an acid halide
or acid anhydride is used preferably. When the reactivity with the
alcohol compound is taken into account, an acid halide is used more
preferably. Furthermore, among the acid halides, acid chloride is
used particularly preferably when availability and storage
stability of the compound are taken into account. The production
process including these steps allows a polymerizable monomer to be
obtained with high yield and therefore is suitable for industrial
production.
[0054] The compound in which primary hydroxyl groups of the alcohol
compound are protected beforehand can be obtained as a commercially
available product, for example,
1,2:5,6-di-O-isopropylidene-D-mannitol and
1,3:4,6-di-O-benzylidene-D-mannitol. Furthermore, it also can be
produced by carrying out a step of protecting the primary hydroxyl
groups of the alcohol compound. In a compound in which primary
hydroxyl groups of the alcohol compound are protected beforehand,
it is preferable that a part of hydroxyl groups other than the
primary hydroxyl groups be protected while a plurality of hydroxyl
groups are allowed to remain. In this manner, a structure having at
least three hydroxyl groups is obtained easily.
[0055] The step of protecting the primary hydroxyl groups of the
alcohol compound can be carried out by performing a known reaction
for introducing protecting groups.
[0056] It is advantageous to select a group that is introduced
preferentially into a primary hydroxyl group, as a protecting group
for the primary hydroxyl groups of the alcohol compound.
Furthermore, for the protecting group, it is advantageous to select
one that tends not to undergo a deprotection reaction during the
esterification reaction and tends not to allow the ester bond to be
cleaved during the deprotection reaction. From these viewpoints,
protecting groups that are used preferably are ether protecting
groups, silyl ether protecting groups, and acetal protecting
groups. Ether protecting groups that are used more preferably are a
1-ethoxyethyl ether group and triphenylmethyl ether group. Silyl
ether protecting groups that are used more preferably are a
triisopropylsilyl ether group, t-butyldimethylsilyl ether group,
and t-butyldiphenylsilyl ether group. Each of these protecting
groups can be introduced preferentially into a primary hydroxyl
group and can be deprotected under a mild acidic condition, and
therefore it has an advantage that deprotection can be achieved
without cleaving the ester bond. On the other hand, acetal
protecting groups that are used more preferably are an
isopropylidene group, cycloheptylidene group, benzylidene group,
and p-methoxybenzylidene group. When using an acetal protecting
group, it not only can be introduced preferentially into a primary
hydroxyl group but also can protect two or more hydroxyl groups
including the primary hydroxyl group at the same time. Accordingly,
the acetal protecting group is especially suitable for synthesis of
the polymerizable monomer (A). Therefore, among the ether
protecting groups, silyl ether protecting groups, and acetal
protecting groups, the acetal protecting groups are used further
preferably. Moreover, from the viewpoints that deprotection is
possible under a particularly mild acidic condition and a byproduct
produced at the time of deprotection can be removed easily, an
isopropylidene group is used particularly preferably.
[0057] The step of esterifying a compound in which primary hydroxyl
groups of the alcohol compound are protected beforehand and a
carboxylic acid having a polymerizable group or a derivative
thereof can be carried out according to a known method. For the
esterification reaction, it is important to select suitable
reaction conditions (particularly, the temperature condition and
the type of catalyst) under which a deprotection reaction tends not
to occur, with consideration given to the type of the protecting
group. Furthermore, it is important to select the reaction
conditions (particularly, the amounts of the compound in which
primary hydroxyl groups of the alcohol compound are protected
beforehand and the carboxylic acid having a polymerizable group or
a derivative thereof to be used) so that after the esterification
reaction, a plurality of ester bonds are formed and the total
number of the protected hydroxyl groups and unreacted hydroxyl
groups is at least three, in one molecule.
[0058] The step of deprotecting the protecting groups of the
primary hydroxyl groups of the resultant ester compound may be
carried out according to a known method depending on the type of
the protecting group. In this case, it is important to select
reaction conditions (particularly, the temperature condition and
the type of catalyst) under which the ester bond tends not to be
cleaved. As described above, when the ether protecting groups,
silyl ether protecting groups, and acetal protecting groups that
are preferable as the protecting group of the primary hydroxyl
group are used, all of them can be deprotected under mild acidic
conditions and therefore deprotection can be performed without
allowing the ester bond to be cleaved. Furthermore, the silyl ether
protecting groups can be deprotected with extremely high
selectivity by the use of a fluorine-containing compound such as
TBAF (tetrabutylammonium fluoride) and thus are highly useful. In
the case of deprotection under an acidic condition, for example,
mineral acids such as hydrochloric acid and sulfuric acid and
aqueous solutions thereof; organic acids such as formic acid,
acetic acid, and trifluoroacetic acid and aqueous solutions
thereof; and cation exchange resin are used preferably. Among
these, since the acidity is suitable and deprotection can be
performed with cleavage of the ester bond being prevented
efficiently, organic acids such as formic acid, acetic acid, and
trifluoroacetic acid and aqueous solutions thereof are more
preferable, and formic acid, acetic acid, and aqueous solutions
thereof are further preferable.
[0059] Since the polymerizable monomer (A) has a plurality of
polymerizable groups and a plurality of hydroxyl groups, it is
excellent in crosslinking reactivity and can interact strongly with
a compound having a hydrophilic group. Accordingly, when the
polymerizable monomer is mixed with a suitable component into a
composition, the composition thus obtained exhibits excellent
curability and adhesive properties in various applications
including dental applications. From the viewpoint of obtaining both
curability and adhesive properties to a tooth structure of the
composition in a balanced manner, compounds represented by the
aforementioned formulae (7) and (8) can be used in combination.
[0060] The amount of polymerizable monomer (A) to be added may be
determined appropriately according to the application of the
composition. Preferably, 1 to 99 parts by mass of polymerizable
monomer (A) is contained in 100 parts by mass of the whole amount
of polymerizable monomer components (other polymerizable monomer
components will be described later). When a composition in which
the amount of the polymerizable monomer (A) to be added is in such
a range is used as a dental composition, there are advantages that
penetrability into a collagen layer of dentin is excellent and bond
strength is high. When the amount of polymerizable monomer (A) to
be added is less than 1 part by mass, bond strength may be reduced
and bond durability also may be reduced. Therefore, the amount is
more preferably at least 2 parts by mass and further preferably at
least 5 parts by mass. On the other hand, the amount of
polymerizable monomer (A) to be added exceeding 99 parts by mass
results in insufficient decalcification and sufficiently high bond
strength may not be obtained. Therefore the amount is more
preferably 98 parts by mass or less and further preferably 95 parts
by mass or less.
[0061] Bisacylphosphine oxide (B) represented by formula (1)
##STR00015##
[0062] In the above formula, R.sup.4 indicates an alkyl group,
alkenyl group, alkynyl group, aryl group, alkoxy group, acyl group,
or acyloxy group, and R.sup.5 to R.sup.14 are each independently a
hydrogen atom, halogen atom, alkyl group, alkenyl group, alkynyl
group, aryl group, alkoxy group, acyl group, or acyloxy group.
[0063] The bisacylphosphine oxide (B) acts as a photopolymerization
initiator. As a result of studies made by the present inventors,
they found that when bisacylphosphine oxide (B) combined with the
polymerizable monomer (A) was used for a dental application, a
composition was obtained that was exceptionally excellent in
adhesive properties to a tooth structure. The reason why the
adhesive properties increase considerably when bisacylphosphine
oxide (B) is used in combination is surmised as follows. A
composition containing a polymerizable monomer (A) has high
penetrability into a collagen layer of dentin. However, in the
portion where this polymerizable monomer (A) has penetrated into
the collagen layer, light for initiating polymerization tends not
to reach and therefore polymerization tends not to occur.
Accordingly, it is considered that in the case of initiators used
widely such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide(TMDPO)
and camphorquinone (CQ), the cure degree is not so high in the
portion where the polymerizable monomer (A) has penetrated into the
collagen layer, and the effect of improving penetrability by the
polymerizable monomer (A) cannot be fully used. However,
conceivably, the bisacylphosphine oxide (B) makes it possible to
cure the polymerizable monomer (A) sufficiently even in the portion
where the polymerizable monomer (A) has penetrated into the
collagen layer and as a result, adhesive properties improve
surprisingly.
[0064] Alkyl groups having 1 to 10 carbon atoms are preferable as
the alkyl groups indicated with R.sup.4 to R.sup.14, and examples
thereof include a methyl group, ethyl group, n-propyl group,
isopropyl group, cyclopropyl group, n-butyl group, isobutyl group,
sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl
group, isopentyl group, neopentyl group, tert-pentyl group,
2,4,4-trimethylpentyl group, cyclopentyl group, n-hexyl group,
isohexyl group, cyclohexyl group, n-heptyl group, cycloheptanyl
group, n-octyl group, 2-ethylhexyl group, cyclooctanyl group,
n-nonyl group, cyclononanyl group, and n-decyl group.
[0065] Alkenyl groups having 2 to 10 carbon atoms are preferable as
the alkenyl groups indicated with R.sup.4 to R.sup.14, and examples
thereof include a vinyl group, allyl group, methylvinyl group,
propenyl group, butenyl group, pentenyl group, hexenyl group,
cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, and
cyclohexenyl group.
[0066] Alkynyl groups having 2 to 10 carbon atoms are preferable as
the alkynyl groups indicated with R.sup.4 to R.sup.14, and examples
thereof include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl,
1-methyl-2-propynyl, 2-butynyl, 3-butynyl, 1-pentynyl,
1-ethyl-2-propynyl, 2-pentynyl, 3-pentynyl, 1-methyl-2-butynyl,
4-pentynyl, 1-methyl-3-butynyl, 2-methyl-3-butynyl, 1-hexynyl,
2-hexynyl, 1-ethyl-2-butynyl, 3-hexynyl, 1-methyl-2-pentynyl,
1-methyl-3-pentynyl, 4-methyl-1-pentynyl, 3-methyl-1-pentynyl,
5-hexynyl, and 1-ethyl-3-butynyl.
[0067] Aryl groups having 6 to 30 carbon atoms are preferable as
the aryl groups indicated with R.sup.4 to R.sup.14, and examples
thereof include a phenyl group, o-tolyl group, m-tolyl group,
p-tolyl group, xylyl group, mesityl group, naphthyl group, and
anthracenyl group. These aryl groups further may include an alkyl
group, alkoxy group, alkenyl group, and alkynyl group.
[0068] Alkoxy groups having 1 to 10 carbon atoms are preferable as
the alkoxy groups indicated with R.sup.4 to R.sup.14, and examples
thereof include a methoxy group, ethoxy group, n-propoxy group,
isopropoxy group, cyclopropyropoxy group, n-butoxy group, isobutoxy
group, sec-butoxy group, tert-butoxy group, cyclobutoxy group, and
cyclohexyloxy group.
[0069] Acyl groups having 1 to 10 carbon atoms are preferable as
the acyl groups indicated with R.sup.4 to R.sup.14, and examples
thereof include: formyl groups; alkylcarbonyl groups having 2 to 10
carbon atoms such as an acetyl group, propionyl group, butyryl
group, isobutyryl group, valeryl group, pivaloyl group, hexanoyl
group, heptanoyl group, octanoyl group, and decenoyl group;
arylcarbonyl groups having 7 to 10 carbon atoms such as a benzoyl
group; and arylalkylcarbonyl groups having 8 to 10 carbon atoms
such as a benzylcarbonyl group.
[0070] Acyloxy groups having 1 to 10 carbon atoms are preferable as
the acyloxy groups indicated with R.sup.4 to R.sup.14, and examples
thereof include groups in which one oxygen atom is bonded to each
of the groups described above as examples of the acyl groups.
[0071] Examples of halogen atoms indicated with R.sup.5 to R.sup.14
include a fluorine atom, chlorine atom, and bromine atom. Among
these, a chlorine atom is preferable.
[0072] An alkyl group and aryl group each are preferable as
R.sup.4. A hydrogen atom, halogen atom, alkyl group, and alkoxy
group are preferable as R.sup.5 to R.sup.14. Examples of the
bisacylphosphine oxide (B) represented by formula (1) include
bis-(2,6-dichlorobenzoyl)phenylphosphine oxide,
bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide,
bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide,
bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide,
bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide,
bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide,
bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide,
bis-(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and
(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.
[0073] Preferably, 0.01 to 20 parts by mass of bisacylphosphine
oxide (B) is contained with respect to 100 parts by mass of the
whole amount of polymerizable monomer components. When the amount
of bisacylphosphine oxide (B) to be added is less than 0.01 part by
mass, polymerization may not proceed sufficiently, which may result
in a reduction in bond strength. Accordingly, it is more preferably
at least 0.05 part by mass and further preferably at least 0.1 part
by mass. On the other hand, when the amount of bisacylphosphine
oxide (B) to be added exceeds 20 parts by mass, sufficiently high
bond strength may not be obtained and further precipitation from
the composition may occur. Accordingly, it is more preferably 18
parts by mass or less, further preferably 15 parts by mass or less,
and most preferably 10 parts by mass or less.
[0074] Next, arbitrary components of the composition according to
the present invention are described. The composition of the present
invention may contain components other than the polymerizable
monomer (A) and bisacylphosphine oxide (B) depending on the
application of the composition. For instance, the composition of
the present invention may contain, as a polymerizable monomer
component other than the polymerizable monomer (A), polymerizable
monomer components such as a polymerizable monomer (C) having one
polymerizable group and at least one hydroxyl group, a
polymerizable monomer (D) having an acidic group, and a
crosslinkable polymerizable monomer (E). Furthermore, the
composition of the present invention may contain a solvent (F), a
polymerization accelerator (H), and a filler (I). Moreover, the
composition may contain at least one polymerization initiator (G)
selected from the group consisting of acylphosphine oxides,
water-soluble acylphosphine oxides, thioxanthones, quaternary
ammonium salts of thioxanthones, ketals, alpha-diketones,
coumarins, anthraquinones, benzoin alkyl ether compounds,
alpha-amino ketone compounds, and organic peroxides.
[0075] In the present invention, the phrase "the whole amount of
polymerizable monomer components" denotes the total amount of the
polymerizable monomer (A) and polymerizable monomers (C) to
(E).
[0076] In the following description, terms "monofunctional",
"bifunctional", and "trifunctional" are used and the terms
"monofunctional", "bifunctional", and "trifunctional" indicate that
one, two, and three polymerizable groups each are contained in one
molecule. Preferably, these polymerizable groups are groups that
are radical-copolymerizable with polymerizable groups of the
polymerizable monomer (A).
[0077] Polymerizable Monomer (C) Having One Polymerizable Group and
at Least One Hydroxyl Group
[0078] Preferably, the composition of the present invention
contains a polymerizable monomer (C) having one polymerizable group
and at least one hydroxyl group. When the composition of the
present invention contains a polymerizable monomer (C),
particularly when it is used as a dental composition, excellent
bond strength is obtained. Since the polymerizable monomer (C) has
a polymerizable group, not only radical polymerization can occur
but also copolymerization with another monomer can occur. The
polymerizable monomer (C) having one polymerizable group and at
least one hydroxyl group is not particularly limited. The
polymerizable group of the polymerizable monomer (C) is preferably
a group that is radical-copolymerizable with a polymerizable group
of the polymerizable monomer (A). From the viewpoint of ease of
radical polymerization, the polymerizable group of the
polymerizable monomer (C) is preferably a (meth)acrylic group or
(meth)acrylamide group. The polymerizable monomer (C) is used
preferably as a component of a dental composition. However, since
the inside of an oral cavity has a humid environment, the
polymerizable group may be detached by, for example, hydrolysis.
When consideration is given to stimulativeness of a detached
polymerizable group to a biological body, the polymerizable group
of the polymerizable monomer (C) is preferably a methacrylic group
or methacrylamide group.
[0079] The polymerizable monomer (C) has at least one hydroxyl
group and therefore has excellent hydrophilicity, and it is a
monofunctional polymer monomer having one polymerizable group.
Accordingly, when a composition of the present invention containing
a polymerizable monomer (A) and a polymerizable monomer (C) is used
as a dental composition, an effect that the penetrability into a
collagen layer of dentin is further excellent also is obtained.
[0080] Polymerizable monomers (C) can be used independently or two
or more of them can be used in suitable combination. Examples of
the polymerizable monomers (C) include
2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate,
4-hydroxybutyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate,
10-hydroxydecyl(meth)acrylate, propylene glycol mono(meth)acrylate,
glycerol mono(meth)acrylate, erythritol mono(meth)acrylate,
N-methylol(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, and
N,N-(dihydroxyethyl)(meth)acrylamide. Among these, from the
viewpoint of improving the penetrability into a collagen layer of
dentin, 2-hydroxyethyl(meth)acrylate,
3-hydroxypropyl(meth)acrylate, glycerol mono(meth)acrylate, and
erythritol mono(meth)acrylate are preferable and
2-hydroxyethylmethacrylate is particularly preferable.
[0081] The amount of polymerizable monomer (C) to be added is not
particularly limited, but it is preferable that 1 to 90 parts by
mass of polymerizable monomer (C) be contained in 100 parts by mass
of the whole amount of polymerizable monomer components. When a
composition in which the amount of polymerizable monomer (C) to be
added is in such a range is used as a dental composition, both
excellent penetrability into a collagen layer of dentin and
excellent bond strength are obtained. When the amount of
polymerizable monomer (C) to be added is less than 1 part by mass,
contribution of the polymerizable monomer (C) to penetration into a
collagen layer of dentin may not be obtained and the bond strength
may be reduced. The amount of polymerizable monomer (C) to be added
is more preferably at least 3 parts by mass, further preferably at
least 5 parts by mass, and particularly preferably at least 7 parts
by mass. On the other hand, when the amount of polymerizable
monomer (C) to be added exceeds 90 parts by mass, sufficiently high
curability cannot be obtained and therefore the mechanical strength
of the cured product may be reduced. Accordingly, the bond strength
may be reduced. The amount of polymerizable monomer (C) to be added
is more preferably 80 parts by mass or less, further preferably 75
parts by mass or less, and particularly preferably 70 parts by mass
or less.
[0082] Polymerizable Monomer (D) Having Acidic Group
[0083] Preferably, the composition of the present invention
contains a polymerizable monomer (D) having an acidic group. When a
composition containing a polymerizable monomer (D) having an acidic
group is used as a dental composition, the polymerizable monomer
(D) itself that has an acidic group has an acid-etching effect and
a primer treatment effect. Therefore, it has advantages that, for
example, pretreatments such as an acid etching treatment and a
primer treatment are not necessary. Accordingly, a combination with
a polymerizable monomer (D) having an acidic group makes it
possible to provide a bonding material that is simple to use and
has high bond strength and excellent bond durability, particularly
preferably a one-component bonding material.
[0084] Polymerizable monomers (D) having acidic groups can be used
independently or two or more of them can be used in suitable
combination. The polymerizable monomers (D) having acidic groups
are not particularly limited. Examples thereof include a
monofunctional polymerizable monomer having one carboxyl group or
an acid anhydride group thereof in the molecule, a monofunctional
polymerizable monomer having a plurality of carboxyl groups or an
acid anhydride group thereof in the molecule, and a monofunctional
polymerizable monomer having a phosphinyloxy group or phosphonooxy
group in the molecule (also referred to as a monofunctional radical
polymerizable phosphoric acid ester).
[0085] Examples of the monofunctional polymerizable monomer having
one carboxyl group or an acid anhydride group thereof in the
molecule include (meth)acrylic acid, N-(meth)acryloylglycine,
N-(meth)acryloylaspartic acid, N-(meth)acryloyl-5-aminosalicylic
acid, 2-(meth)acryloyloxyethyl hydrogen succinate,
2-(meth)acryloyloxyethyl hydrogen phthalate,
2-(meth)acryloyloxyethyl hydrogen malate, 6-(meth)acryloyloxyethyl
naphthalene-1,2,6-tricarboxylic acid, O-(meth)acryloyltyrosine,
N-(meth)acryloyltyrosine, N-(meth)acryloylphenylalanine,
N-(meth)acryloyl-p-aminobenzoic acid,
N-(meth)acryloyl-o-aminobenzoic acid, p-vinylbenzoic acid,
2-(meth)acryloyloxybenzoic acid, 3-(meth)acryloyloxybenzoic acid,
4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-4-aminosalicylic
acid, and compounds obtained by converting the carboxyl group of
these compounds into an acid anhydride group.
[0086] Examples of the monofunctional polymerizable monomer having
a plurality of carboxyl groups or an acid anhydride group thereof
in the molecule include
11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid,
10-(meth)acryloyloxydecane-1,1-dicarboxylic acid,
12-(meth)acryloyloxydodecane-1,1-dicarboxylic acid,
6-(meth)acryloyloxyhexane-1,1-dicarboxylic acid,
2-(meth)acryloyloxyethyl-3'-methacryloyloxy-2'-(3,4-dicarboxybenzoyloxy)--
propyl succinate, 4-(2-(meth)acryloyloxyethyl)trimeritate
anhydride, 4-(2-(meth)acryloyloxyethyl)trimeritate,
4-(meth)acryloyloxyethyl trimeritate, 4-(meth)acryloyloxybutyl
trimeritate, 4-(meth)acryloyloxyhexyl trimeritate,
4-(meth)acryloyloxydecyl trimeritate,
6-(meth)acryloyloxyethylnaphthalene-1,2,6-tricarboxylic acid
anhydride, 6-(meth)acryloyloxyethylnaphthalene-2,3,6-tricarboxylic
acid anhydride,
4-(meth)acryloyloxyethylcarbonylpropionoyl-1,8-naphthalic acid
anhydride, 4-(meth)acryloyloxyethylnaphthalene-1,8-tricarboxylic
acid anhydride, 9-(meth)acryloyloxynonane-1,1-dicarboxylic acid,
13-(meth)acryloyloxytridecane-1,1-dicarboxylic acid, and
11-(meth)acrylamideundecane-1,1-dicarboxylic acid.
[0087] Examples of the monofunctional polymerizable monomer having
a phosphinyloxy group or phosphonooxy group in the molecule (also
referred to as a monofunctional radical polymerizable phosphoric
acid ester) include 2-(meth)acryloyloxyethyl dihydrogenphosphate,
2-(meth)acryloyloxyethylphenyl hydrogenphosphate,
10-(meth)acryloyloxydecyl dihydrogenphosphate,
6-(meth)acryloyloxyhexyl dihydrogenphosphate,
2-(meth)acryloyloxyethyl-2-bromoethyl hydrogenphosphate, and
2-(meth)acrylamideethyl dihydrogenphosphate.
[0088] Examples of other monofunctional polymerizable monomer
having an acidic group include a monofunctional polymerizable
monomer having a sulfo group in the molecule such as
2-(meth)acrylamide-2-methylpropanesulfonic acid and
10-sulfodecyl(meth)acrylate.
[0089] The amount of polymerizable monomer (D) having an acidic
group to be added is not particularly limited but it is preferable
that 1 to 90 parts by mass of polymerizable monomer (D) having an
acidic group be contained in 100 parts by mass of the whole amount
of polymerizable monomer components. When the amount of
polymerizable monomer (D) having an acidic group to be added is
less than 1 part by mass, the acid-etching effect or primer
treatment effect may not be obtained. Therefore, the amount is more
preferably at least 2 parts by mass and further preferably at least
5 parts by mass. On the other hand, when the amount of
polymerizable monomer (D) having an acidic group to be added
exceeds 90 parts by mass, sufficiently high curability may not be
obtained and therefore the adhesive properties may be deteriorated.
Accordingly, the amount is more preferably 80 parts by mass or less
and further preferably 70 parts by mass or less.
[0090] Crosslinkable Polymerizable Monomer (E)
[0091] Preferably, the composition of the present invention
contains a crosslinkable polymerizable monomer (E). When a
composition containing a crosslinkable polymerizable monomer (E) is
used as a dental composition, it has advantages such as a further
improvement in bond strength.
[0092] Crosslinkable polymerizable monomers (E) can be used
independently or two or more of them can be used in suitable
combination. The crosslinkable polymerizable monomers (E) are not
particularly limited. Examples thereof include an aromatic
compound-based bifunctional polymerizable monomer, an aliphatic
compound-based bifunctional polymerizable monomer, and
trifunctional or higher polymerizable monomers.
[0093] Examples of the aromatic compound-based bifunctional
polymerizable monomer include
2,2-bis((meth)acryloyloxyphenyl)propane,
2,2-bis[4-(3-(meth)acryloyloxy)-2-hydroxypropoxyphenyl]propane
(commonly known as "Bis-GMA"),
2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxydipropoxyphenyl)propane,
2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)-
-propane,
2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytrie-
thoxy-phenyl)propane,
2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxy-ph-
enyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane,
2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, and
1,4-bis(2-(meth)acryloyloxyethyl)pyromeritate.
[0094] Examples of the aliphatic compound-based bifunctional
polymerizable monomer include ethylene glycol di(meth)acrylate,
diethylene glycol di(meth)acrylate, triethylene glycol
di(meth)acrylate, propylene glycol di(meth)acrylate, butylene
glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate,
polyethylene glycol di(meth)acrylate, 1,3-butanediol
di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol
di(meth)acrylate, 1,10-decanediol di(meth)acrylate,
1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, and
2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate
(commonly known as "UDMA").
[0095] Examples of the trifunctional or higher polymerizable
monomers include trimethylolpropane tri(meth)acrylate,
trimethylolethane tri(meth)acrylate, trimethylolmethane
tri(meth)acrylate, pentaerythritol tri(meth)acrylate,
pentaerythritol tetra(meth)acrylate, dipentaerythritol
tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate,
dipentaerythritol hexa(meth)acrylate,
N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]te-
tramethacrylate, and
1,7-diacryloyloxy-2,2,6,6-tetraacryloyloxymethyl-4-oxyheptane.
[0096] The amount of crosslinkable polymerizable monomer (E) to be
added is not particularly limited, but it is preferable that 1 to
90 parts by mass of crosslinkable polymerizable monomer (E) be
contained in 100 parts by mass of the whole amount of polymerizable
monomer components. When the amount of crosslinkable polymerizable
monomer (E) to be added is less than 1 part by mass, sufficiently
high bond strength may not be obtained. Therefore, the amount is
more preferably at least 2 parts by mass and further preferably at
least 5 parts by mass. On the other hand, when the amount of
crosslinkable polymerizable monomer (E) to be added exceeds 90
parts by mass, the composition may not penetrate sufficiently into
a collagen layer of dentin and thereby high bond strength may not
be obtained. Therefore, the amount is more preferably 80 parts by
mass or less and further preferably 70 parts by mass or less.
[0097] The composition of the present invention may contain a
polymerizable monomer other than the aforementioned (A), (C), (D),
and (E) as required.
[0098] Solvent (F)
[0099] Preferably, the composition of the present invention
contains a solvent (F) depending on the specific embodiment.
Examples of the solvent include water (J), an organic solvent (K),
and a mixed solvent thereof.
[0100] When the composition of the present invention contains water
(J), it exhibits both excellent bond strength and excellent bond
durability. Preferably, the content of water (J) is 6 to 2000 parts
by mass with respect to 100 parts by mass of the whole amount of
polymerizable monomer components. When the content of water (J) is
less than 6 parts by mass, the monomer may not penetrate
sufficiently into a collagen layer and the bond strength may be
reduced. On the other hand, when the content of water (I) exceeds
2000 parts by mass, the polymerizability of the monomer may be
deteriorated and both the bond strength and bond durability may be
reduced. The content of water (J) is more preferably at least 7
parts by mass and further preferably at least 10 parts by mass.
Furthermore, the content of water (J) is more preferably 1500 parts
by mass or less. Preferably, water (J) is free of impurities that
have adverse effects, and distilled water or ion exchanged water is
preferable.
[0101] Organic solvents (K) can be used independently or two or
more of them can be used in suitable combination. Examples of the
organic solvent (K) include methanol, ethanol, 1-propanol,
2-propanol, 1-butanol, 2-methyl-2-propanol, acetone, methyl ethyl
ketone, tetrahydrofuran, diethyl ether, diisopropyl ether, hexane,
toluene, chloroform, ethyl acetate, and butyl acetate.
Particularly, when both safety to biological bodies and easy
removal based on volatility are taken into consideration, the
organic solvent (E) is preferably a water-soluble organic solvent.
Specifically, ethanol, 2-propanol, 2-methyl-2-propanol, acetone,
and tetrahydrofuran are used preferably. The content of organic
solvent (K) is not particularly limited and the organic solvent (K)
may not need to be added depending on the embodiment. In an
embodiment using the organic solvent, it is preferable that 1 to
2000 parts by mass of organic solvent (K) be contained with respect
to 100 parts by mass of the whole amount of polymerizable monomer
components. The preferable amount of the organic solvent (K) to be
added varies considerably depending on the embodiment in which it
is used. Therefore, preferable amounts of organic solvents (K) to
be added according to respective embodiments are indicated together
with description of specific embodiments of the composition of the
present invention described later.
[0102] Polymerization Initiator (G)
[0103] The composition of the present invention further may contain
a polymerization initiator (G) other than the bisacylphosphine
oxide (B), preferably at least one polymerization initiator (G)
selected from the group consisting of acylphosphine oxides,
water-soluble acylphosphine oxides, thioxanthones, quaternary
ammonium salts of thioxanthones, ketals, alpha-diketones,
coumarins, anthraquinones, benzoin alkyl ether compounds,
alpha-amino ketone compounds, and organic peroxide. This
polymerization initiator (G) may be either a photopolymerization
initiator or a chemical polymerization initiator. Examples of the
photopolymerization initiator include acylphosphine oxides,
water-soluble acylphosphine oxides, thioxanthones, quaternary
ammonium salts of thioxanthones, ketals, alpha-diketones,
coumarins, anthraquinones, benzoin alkyl ether compounds, and
alpha-amino ketone compounds.
[0104] Examples of acylphosphine oxides used as the
photopolymerization initiator include
2,4,6-trimethylbenzoyldiphenylphosphine oxide,
2,6-dimethoxybenzoyldiphenylphosphine oxide,
2,6-dichlorobenzoyldiphenylphosphine oxide,
2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide,
2,4,6-trimethylbenzoylethoxyphenylphosphine oxide,
2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, and benzoyl
di-(2,6-dimethylphenyl) phosphonate.
[0105] Preferably, the water-soluble acylphosphine oxides used as
the photopolymerization initiator have alkali metal ions, alkaline
earth metal ions, pyridinium ions, or ammonium ions in the
acylphosphine oxide molecules. For instance, the water-soluble
acylphosphine oxides can be synthesized by the method disclosed in
EP 0009348 or JP 57(1982)-197289 A.
[0106] Specific examples of the aforementioned water-soluble
acylphosphine oxides include sodium monomethylacetylphosphonate,
sodium monomethyl(1-oxopropyl)phosphonate, sodium
monomethylbenzoylphosphonate, sodium
monomethyl(1-oxobutyl)phosphonate, sodium
monomethyl(2-methyl-1-oxopropyl)phosphonate, sodium
acetylphosphonate, sodium monomethylacetylphosphonate, sodium
acetylmethylphosphonate,
methyl-4-(hydroxymethoxyphosphinyl)-4-oxobutanoate sodium salt,
methyl-4-oxophosphonobutanoate monosodium salt,
acetylphenylphosphinate sodium salt, sodium
(1-oxopropyl)pentylphosphinate,
methyl-4-(hydroxypentylphosphinyl)-4-oxobutanoate sodium salt,
sodium acetylpentylphosphinate, sodium acetylethylphosphinate,
sodium methyl(1,1-dimethyl)methylphosphinate, sodium
(1,1-diethoxyethyl)methylphosphinate, sodium
(1,1-diethoxyethyl)methylphosphinate,
methyl-4-(hydroxymethylphosphinyl)-4-oxobutanoate lithium salt,
4-(hydroxymethylphosphinyl)-4-oxobutanoic acid dilithium salt,
methyl(2-methyl-1,3-dioxolan-2-yl)phosphinate sodium salt,
methyl(2-methyl-1,3-thiazolidin-2-yl)phosphonite sodium salt,
(2-methylperhydro-1,3-diazin-2-yl)phosphonite sodium salt,
acetylphosphinate sodium salt, (1,1-diethoxyethyl)phosphonite
sodium salt, (1,1-diethoxyethyl)methylphosphonite sodium salt,
methyl(2-methyloxathiolane-2-yl)phosphinate sodium salt,
methyl(2,4,5-trimethyl-1,3-dioxolan-2-yl)phosphinate sodium salt,
methyl(1,1-propoxyethyl)phosphinate sodium salt,
(1-methoxyvinyl)methylphosphinate sodium salt,
(1-ethylthiovinyl)methylphosphinate sodium salt,
methyl(2-methylperhydro-1,3-diazin-2-yl)phosphinate sodium salt,
methyl(2-methylperhydro-1,3-thiazin-2-yl)phosphinate sodium salt,
methyl(2-methyl-1,3-diazolidin-2-yl)phosphinate sodium salt,
methyl(2-methyl-1,3-thiazolidin-2-yl)phosphinate sodium salt,
(2,2-dicyano-1-methylethynyl)phosphinate sodium salt,
acetylmethylphosphinate oxime sodium salt,
acetylmethylphosphinate-O-benzyloxime sodium salt,
1-[(N-ethoxyimino)ethyl]methylphosphinate sodium salt,
methyl(1-phenyliminoethyl)phosphinate sodium salt,
methyl(1-phenylhydrazone ethyl)phosphinate sodium salt,
[1-(2,4-dinitrophenylhydrazono)ethyl]methylphosphinate sodium salt,
acetylmethylphosphinate semicarbazone sodium salt,
(1-cyano-1-hydroxyethyl)methylphosphinate sodium salt,
(dimethoxymethyl)methyl phosphinate sodium salt,
formylmethylphosphinate sodium salt,
(1,1-dimethoxypropyl)methylphosphinate sodium salt,
methyl(1-oxopropyl)phosphinate sodium salt, dodecylguanidine salt
of (1,1-dimethoxypropyl)methylphosphinate, isopropylamine salt of
(1,1-dimethoxypropyl)methylphosphinate, acetylmethylphosphinate
thiosemicarbazone sodium salt,
1,3,5-tributyl-4-methylamino-1,2,4-triazolium
(1,1-dimethoxyethyl)-methylphosphinate,
1-butyl-4-butylaminomethylamino-3,5-dipropyl-1,2,4-triazolium
(1,1-dimethoxyethyl)-methylphosphinate,
2,4,6-trimethylbenzoylphenylphosphine oxide sodium salt,
2,4,6-trimethylbenzoylphenylphosphine oxide potassium salt, and
ammonium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide.
Furthermore, examples thereof also include compounds described in
JP 2000-159621 A.
[0107] Among these acylphosphine oxides and water-soluble
acylphosphine oxides, particularly preferable ones are
2,4,6-trimethylbenzoyldiphenylphosphine oxide,
2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, and
2,4,6-trimethylbenzoylphenylphosphine oxide sodium salt.
[0108] Examples of thioxanthones or the quaternary ammonium salts
of thioxanthones that are used as the above-mentioned
photopolymerization initiators include thioxanthone,
2-chlorothioxanthen-9-one,
2-hydroxy-3-(9-oxy-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-propaneaminium
chloride,
2-hydroxy-3-(1-methyl-9-oxy-9H-thioxanthen-4-yloxy)-N,N,N-trime-
thyl-propaneaminium chloride,
2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-propaneaminium
chloride,
2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-t-
rimethyl-1-propaneaminium chloride,
2-hydroxy-3-(3,4-dimethyl-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propa-
neaminium chloride, and
2-hydroxy-3-(1,3,4-trimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethy-
l-1-propaneaminium chloride.
[0109] Among the thioxanthones or the quaternary ammonium salts of
thioxanthones, a particularly preferable thioxanthone is
2-chlorothioxanthen-9-one, and a particularly preferable quaternary
ammonium salt of thioxanthone is
2-hydroxy-3-(3,4-dimethyl-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propa-
neaminium chloride.
[0110] Examples of ketals used as the photopolymerization initiator
include benzyl dimethyl ketal and benzyl diethyl ketal.
[0111] Examples of the alpha-diketones used as the
photopolymerization initiator include diacetyl, dibenzyl,
camphorquinone, 2,3-pentadione, 2,3-octadione,
9,10-phenanthrenequinone, 4,4'-oxybenzyl, and acenaphthenequinone.
Among these, camphorquinone is particularly preferable from the
viewpoint of having the maximum absorption wavelength in the
visible light range.
[0112] Examples of the coumarin compound used as the aforementioned
photopolymerization initiator include compounds described in JP
9(1997)-3109 A and JP 10(1998)-245525 A such as
3,3'-carbonylbis(7-diethylamino)coumarin,
3-(4-methoxybenzoyl)coumarin, 3-thienoyl coumarin,
3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin,
3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin,
3-benzoylcoumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin,
3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin),
3-benzoyl-6-bromocoumarin, 3,3'-carbonylbiscoumarin,
3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin,
3-carboxycoumarin, 3-carboxy-7-methoxycoumarin,
3-ethoxycarbonyl-6-methoxycoumarin,
3-ethoxycarbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin,
7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin,
3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin,
7-dimethylamino-3-(4-methoxybenzoyl)coumarin,
7-diethylamino-3-(4-methoxybenzoyl)coumarin,
7-diethylamino-3-(4-diethylamino)coumarin,
7-methoxy-3-(4-methoxybenzoyl)coumarin,
3-(4-nitrobenzoyl)benzo[f]coumarin,
3-(4-ethoxycinnamoyl)-7-methoxycoumarin,
3-(4-dimethylaminocinnamoyl)coumarin,
3-(4-diphenylaminocinnamoyl)coumarin,
3-[(3-dimethylbenzothiazole-2-ilidene)acetyl]coumarin,
3-[(1-methylnaphtho[1,2-d]thiazole-2-ilidene)acetyl]coumarin,
3,3'-carbonylbis(6-methoxycoumarin),
3,3'-carbonylbis(7-acetoxycoumarin),
3,3'-carbonylbis(7-dimethylaminocoumarin),
3-(2-benzothiazoyl)-7-(diethylamino)coumarin,
3-(2-benzothiazoyl)-7-(dibutylamino)coumarin,
3-(2-benzimidazoyl)-7-(diethylamino)coumarin,
3-(2-benzothiazoyl)-7-(dioctylamino)coumarin,
3-acetyl-7-(dimethylamino)coumarin,
3,3'-carbonylbis(7-dibutylaminocoumarin),
3,3'-carbonyl-7-diethylaminocoumarin-7'-bis(butoxyethyl)aminocoumarin,
10-[3-[4-(dimethylamino)phenyl]-1-oxo-2-propenyl]-2,3,6,7-1,1,7,7-tetrame-
thyl 1H, 5H, 11H-[1]benzopyrano[6,7,8-ij]quinolizine-11-one, and
10-(2-benzothiazoyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl 1H, 5H,
11H-[1]-benzopyrano[6,7,8-ij]quinolizin-11-one.
[0113] Among the above-mentioned coumarin compounds, particularly
3,3'-carbonylbis(7-diethylaminocoumarin) and
3,3'-carbonylbis(7-dibutylaminocoumarin) are suitable.
[0114] Examples of the anthraquinones used as the aforementioned
photopolymerization initiator include anthraquinone,
1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone,
1,2-benzanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone,
and 1-hydroxyanthraquinone.
[0115] Examples of the benzoin alkyl ethers used as the
aforementioned photopolymerization initiator include benzoin methyl
ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin
isobutyl ether.
[0116] Examples of the alpha-aminoketones used as the
aforementioned photopolymerization initiator include
2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.
[0117] Preferably, among these photopolymerization initiators, at
least one selected from the group consisting of acylphosphine
oxides, salts thereof, alpha-diketones, and coumarin compounds is
used in combination with the aforementioned bisacylphosphine oxide
(B). This makes it possible to obtain a composition that has
excellent photocurability in visible and near-ultraviolet ranges
and sufficiently high photocurability regardless of which light
source among a halogen lamp, light-emitting diode (LED), and xenon
lamp is used.
[0118] Among the polymerization initiators (G) used in the present
invention, a chemical polymerization initiator that is used
preferably is organic peroxide. The organic peroxide used as the
chemical polymerization initiator is not particularly limited and a
known one can be used. Examples of typical organic peroxides
include ketone peroxide, hydroperoxide, diacyl peroxide, dialkyl
peroxide, peroxyketal, peroxyester, and peroxydicarbonate.
[0119] Examples of ketone peroxide used as the chemical
polymerization initiator include methyl ethyl ketone peroxide,
methyl isobutyl ketone peroxide, methylcyclohexanone peroxide, and
cyclohexanone peroxide.
[0120] Examples of hydroperoxide used as the chemical
polymerization initiator include
2,5-dimethylhexane-2,5-dihydroperoxide, diisopropylbenzene
hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, and
1,1,3,3-tetramethylbutyl hydroperoxide.
[0121] Examples of diacyl peroxide used as the chemical
polymerization initiator include acetyl peroxide, isobutyryl
peroxide, benzoyl peroxide, decanoyl peroxide,
3,5,5-trimethylhexanoyl peroxide, 2,4-dichlorobenzoyl peroxide, and
lauroyl peroxide.
[0122] Examples of dialkyl peroxide used as the chemical
polymerization initiator include di-t-butyl peroxide, dicumyl
peroxide, t-butylcumyl peroxide,
2,5-dimethyl-2,5-di(t-butylperoxy)hexane,
1,3-bis(t-butylperoxyisopropyl)benzene, and
2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne.
[0123] Examples of peroxyketal used as the chemical polymerization
initiator include
1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane,
1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane,
2,2-bis(t-butylperoxy)octane, and 4,4-bis(t-butylperoxy)valeric
acid-n-butyl ester.
[0124] Examples of peroxyester used as the chemical polymerization
initiator include alpha-cumyl peroxyneodecanoate, t-butyl
peroxyneodecanoate, t-butyl peroxypivarate,
2,2,4-trimethylpentylperoxy-2-ethyl hexanoate, t-amylperoxy-2-ethyl
hexanoate, t-butylperoxy-2-ethyl hexanoate, di-t-butylperoxy
isophthalate, di-t-butylperoxy hexahydroterephthalate,
t-butylperoxy-3,3,5-trimethyl hexanoate, t-butylperoxy acetate,
t-butylperoxy benzoate, and t-butylperoxymaleic acid.
[0125] Examples of peroxydicarbonate used as the chemical
polymerization initiator include di-3-methoxy peroxydicarbonate,
di-2-ethylhexyl peroxydicarbonate,
bis(4-t-butylcyclohexyl)peroxydicarbonate, diisopropyl
peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl
peroxydicarbonate, and diallyl peroxydicarbonate.
[0126] Among these organic peroxides, diacyl peroxide is used
preferably from the viewpoint of a comprehensive balance of safety,
storage stability, and radical production ability, and among these,
benzoyl peroxide is used particularly preferably.
[0127] The amount of polymerization initiator (G) to be added in
the present invention is not particularly limited. However, from
the viewpoint of, for example, curability of the resultant
composition, it is preferable that 0.001 to 20 parts by mass of
polymerization initiator (G) be contained with respect to 100 parts
by mass of the whole amount of polymerizable monomer components.
When the amount of polymerization initiator (G) to be added is less
than 0.001 part by mass, polymerization may not proceed
sufficiently and thereby bond strength may be reduced. Therefore,
the amount is more preferably at least 0.05 part by mass and
further preferably at least 0.1 part by mass. On the other hand,
when the amount of polymerization initiator (G) to be added exceeds
20 parts by mass, in the case where the polymerization initiator
itself has low polymerization performance, sufficiently high bond
strength may not be obtained and further precipitation from the
composition may occur. Therefore, the amount is more preferably 15
parts by mass or less and further preferably 10 parts by mass or
less.
[0128] Polymerization Accelerator (H)
[0129] Preferably, the composition of the present invention
contains a polymerization accelerator (H). Examples of the
polymerization accelerator (H) used in the present invention
include amines, sulfinic acids and salts thereof, borate compounds,
barbituric acid derivatives, triazine compounds, copper compounds,
tin compounds, vanadium compounds, halogen compounds, aldehydes,
thiol compounds, sulfite, bisulfite, and thiourea compounds.
[0130] Amines used as the polymerization accelerator (H) can be
divided into aliphatic amines and aromatic amines. Examples of
aliphatic amines include: primary aliphatic amines such as
n-butylamine, n-hexylamine, and n-octylamine; secondary aliphatic
amines such as diisopropylamine, dibutylamine, and
N-methylethanolamine; and tertiary aliphatic amines such as
N-methyldiethanolamine, N-ethyldiethanolamine,
N-n-butyldiethanolamine, N-lauryldiethanolamine,
2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine
dimethacrylate, N-ethyldiethanolamine dimethacrylate,
triethanolamine monomethacrylate, triethanolamine dimethacrylate,
triethanolamine trimethacrylate, triethanolamine, trimethylamine,
triethylamine, and tributylamine. Among these, tertiary aliphatic
amines are preferable from the viewpoint of curability and storage
stability of the composition, and particularly,
N-methyldiethanolamine and triethanolamine are used more
preferably.
[0131] Examples of aromatic amine include
N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline,
N,N-di(2-hydroxyethyl)-p-toluidine,
N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline,
N,N-bis(2-hydroxyethyl)-4-ethylaniline,
N,N-bis(2-hydroxyethyl)-4-isopropylaniline,
N,N-bis(2-hydroxyethyl)-4-t-butylaniline,
N,N-bis(2-hydroxyethyl)-3,5-di-isopropylaniline,
N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline,
N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine,
N,N-diethyl-p-toluidine, N,N-dimethyl-3,5-dimethylaniline,
N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline,
N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline,
N,N-dimethyl-3,5-di-t-butylaniline, 4-N,N-dimethylaminobenzoic acid
ethyl ester, 4-N,N-dimethylaminobenzoic acid methyl ester,
N,N-dimethylaminobenzoic acid n-butoxyethyl ester,
4-N,N-dimethylaminobenzoic acid 2-(methacryloyloxy)ethyl ester,
4-N,N-dimethylaminobenzophenone, and butyl 4-dimethylaminobenzoate.
Among these, at least one selected from the group consisting of
N,N-di(2-hydroxyethyl)-p-toluidine, 4-N,N-dimethylaminobenzoic acid
ethyl ester, N,N-dimethylaminobenzoic acid n-butoxyethyl ester, and
4-N,N-dimethylaminobenzophenone is used preferably from the
viewpoint of being capable of providing the composition with
excellent curability.
[0132] Examples of sulfinic acid and salt thereof used as the
polymerization accelerator (H) include p-toluenesulfinic acid,
sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium
p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic
acid, sodium benzenesulfinate, potassium benzenesulfinate, lithium
benzenesulfinate, calcium benzenesulfinate,
2,4,6-trimethylbenzenesulfinic acid, sodium
2,4,6-trimethylbenzenesulfinate, potassium
2,4,6-trimethylbenzenesulfinate, lithium
2,4,6-trimethylbenzenesulfinate, calcium
2,4,6-trimethylbenzenesulfinate, 2,4,6-triethylbenzenesulfinic
acid, sodium 2,4,6-triethylbenzenesulfinate, potassium
2,4,6-triethylbenzenesulfinate, lithium
2,4,6-triethylbenzenesulfinate, calcium
2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic
acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium
2,4,6-triisopropylbenzenesulfinate, lithium
2,4,6-triisopropylbenzenesulfinate, and calcium
2,4,6-triisopropylbenzenesulfinate. Sodium benzenesulfinate, sodium
p-toluenesulfinate, and sodium 2,4,6-triisopropylbenzenesulfinate
are particularly preferable.
[0133] The borate compound used as the polymerization accelerator
(H) is preferably an arylborate compound. Specific examples of
arylborate compounds that are used preferably include, as a borate
compound having one aryl group in one molecule, sodium salt,
lithium salt, potassium salt, magnesium salt, tetrabutylammonium
salt, tetramethylammonium salt, tetraethylammonium salt,
methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt,
methylquinolinium salt, ethylquinolinium salt, and butylquinolinium
salt of trialkylphenylboron, trialkyl(p-chlorophenyl)boron,
trialkyl(p-fluorophenyl)boron,
trialkyl(3,5-bistrifluoromethyl)phenylboron,
trialkyl[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron,
trialkyl(p-nitrophenyl)boron, trialkyl(m-nitrophenyl)boron,
trialkyl(p-butylphenyl)boron, trialkyl(m-butylphenyl)boron,
trialkyl(p-butyloxyphenyl)boron, trialkyl(m-butyloxyphenyl)boron,
trialkyl(p-octyloxyphenyl)boron, and
trialkyl(m-octyloxyphenyl)boron (each alkyl group is at least one
selected from the group consisting of, for example, an n-butyl
group, an n-octyl group, and an n-dodecyl group).
[0134] Examples of the borate compound having two aryl groups in
one molecule include sodium salt, lithium salt, potassium salt,
magnesium salt, tetrabutylammonium salt, tetramethylammonium salt,
tetraethylammonium salt, methylpyridinium salt, ethylpyridinium
salt, butylpyridinium salt, methylquinolinium salt,
ethylquinolinium salt, and butylquinolinium salt of
dialkyldiphenylboron, dialkyldi(p-chlorophenyl)boron,
dialkyldi(p-fluorophenyl)boron,
dialkyldi(3,5-bistrifluoromethyl)phenylboron,
dialkyldi[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron,
dialkyldi(p-nitrophenyl)boron, dialkyldi(m-nitrophenyl)boron,
dialkyldi(p-butylphenyl)boron, dialkyldi(m-butylphenyl)boron,
dialkyldi(p-butyloxyphenyl)boron, dialkyldi(m-butyloxyphenyl)boron,
dialkyldi(p-octyloxyphenyl)boron, and
dialkyldi(m-octyloxyphenyl)boron (each alkyl group is at least one
selected from the group consisting of, for example, an n-butyl
group, an n-octyl group, and an n-dodecyl group).
[0135] Examples of the borate compound having three aryl groups in
one molecule include sodium salt, lithium salt, potassium salt,
magnesium salt, tetrabutylammonium salt, tetramethylammonium salt,
tetraethylammonium salt, methylpyridinium salt, ethylpyridinium
salt, butylpyridinium salt, methylquinolinium salt,
ethylquinolinium salt, and butylquinolinium salt of
monoalkyltriphenylboron, monoalkyltri(p-chlorophenyl)boron,
monoalkyltri(p-fluorophenyl)boron,
monoalkyltri(3,5-bistrifluoromethyl)phenylboron,
monoalkyltri[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]bor-
on, monoalkyltri(p-nitrophenyl)boron,
monoalkyltri(m-nitrophenyl)boron, monoalkyltri(p-butylphenyl)boron,
monoalkyltri(m-butylphenyl)boron,
monoalkyltri(p-butyloxyphenyl)boron,
monoalkyltri(m-butyloxyphenyl)boron,
monoalkyltri(p-octyloxyphenyl)boron, and
monoalkyltri(m-octyloxyphenyl)boron (each alkyl group is one
selected from, for example, an n-butyl group, an n-octyl group, and
an n-dodecyl group).
[0136] Furthermore, examples of the borate compound having four
aryl groups in one molecule include sodium salt, lithium salt,
potassium salt, magnesium salt, tetrabutylammonium salt,
tetramethylammonium salt, tetraethylammonium salt, methylpyridinium
salt, ethylpyridinium salt, butylpyridinium salt, methylquinolinium
salt, ethylquinolinium salt, and butylquinolinium salt of
tetraphenylboron, tetrakis(p-chlorophenyl)boron,
tetrakis(p-fluorophenyl)boron,
tetrakis(3,5-bistrifluoromethyl)phenylboron,
tetrakis[3,5-bis(1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl)phenyl]boron,
tetrakis(p-nitrophenyl)boron, tetrakis(m-nitrophenyl)boron,
tetrakis(p-butylphenyl)boron, tetrakis(m-butylphenyl)boron,
tetrakis(p-butyloxyphenyl)boron, tetrakis(m-butyloxyphenyl)boron,
tetrakis(p-octyloxyphenyl)boron, tetrakis(m-octyloxyphenyl)boron,
(p-fluorophenyl)triphenylboron,
(3,5-bistrifluoromethyl)phenyltriphenylboron,
(p-nitrophenyl)triphenylboron, (m-butyloxyphenyl)triphenylboron,
(p-butyloxyphenyl)triphenylboron, (m-octyloxyphenyl)triphenylboron,
and (p-octyloxyphenyl)triphenylboron.
[0137] More preferably, from the viewpoint of storage stability,
among these arylborate compounds, a borate compound having three or
four aryl groups in one molecule is used. Furthermore, one of these
arylborate compounds can be used or two or more of them can be used
in mixture.
[0138] Examples of a barbituric acid derivative used as the
polymerization accelerator (H) include barbituric acid,
1,3-dimethylbarbituric acid, 1,3-diphenylbarbituric acid,
1,5-dimethylbarbituric acid, 5-butylbarbituric acid,
5-ethylbarbituric acid, 5-isopropylbarbituric acid,
5-cyclohexylbarbituric acid, 1,3,5-trimethylbarbituric acid,
1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-n-butylbarbituric
acid, 1,3-dimethyl-5-isobutylbarbituric acid,
1,3-dimethylbarbituric acid, 1,3-dimethyl-5-cyclopentylbarbituric
acid, 1,3-dimethyl-5-cyclohexylbarbituric acid,
1,3-dimethyl-5-phenylbarbituric acid,
1-cyclohexyl-1-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric
acid, 5-methylbarbituric acid, 5-propylbarbituric acid,
1,5-diethylbarbituric acid, 1-ethyl-5-methylbarbituric acid,
1-ethyl-5-isobutylbarbituric acid, 1,3-diethyl-5-butylbarbituric
acid, 1-cyclohexyl-5-methylbarbituric acid,
1-cyclohexyl-5-ethylbarbituric acid, 1-cyclohexyl-5-octylbarbituric
acid, 1-cyclohexyl-5-hexylbarbituric acid,
5-butyl-1-cyclohexylbarbituric acid, 1-benzyl-5-phenylbarbituric
acid, and thiobarbituric acids, as well as salts thereof
(particularly, alkali metals or alkaline earth metals are
preferable). Examples of salts of these barbituric acids include
sodium 5-butylbarbiturate, sodium 1,3,5-trimethylbarbiturate, and
sodium 1-cyclohexyl-5-ethylbarbiturate.
[0139] Examples of particularly preferable barbituric acid
derivatives include 5-butylbarbituric acid,
1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric
acid, 1-benzyl-5-phenylbarbituric acid, and sodium salts of these
barbituric acids.
[0140] Examples of the triazine compound used as the polymerization
accelerator (H) include 2,4,6-tris(trichloromethyl)-s-triazine,
2,4,6-tris(tribromomethyl)-s-triazine,
2-methyl-4,6-bis(trichloromethyl)-s-triazine,
2-methyl-4,6-bis(tribromomethyl)-s-triazine,
2-phenyl-4,6-bis(trichloromethyl)-s-triazine,
2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-methylthiophenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(2,4-dichlorophenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-bromophenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine,
2-n-propyl-4,6-bis(trichloromethyl)-s-triazine,
2-(.alpha.,.alpha.,.beta.-trichloroethyl)-4,6-bis(trichloromethyl)-s-tria-
zine, 2-styryl-4,6-bis(trichloromethyl)-s-triazine,
2-[2-(p-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine,
2-[2-(o-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine,
2-[2-(p-butoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine,
2-[2-(3,4-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine,
2-[2-(3,4,5-trimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine-
, 2-(1-naphthyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(4-biphenylyl)-4,6-bis(trichloromethyl)-s-triazine,
2-[2-{N,N-bis(2-hydroxyethyl)amino}ethoxy]-4,6-bis(trichloromethyl)-s-tri-
azine,
2-[2-{N-hydroxyethyl-N-ethylamino}ethoxy]-4,6-bis(trichloromethyl)--
s-triazine,
2-[2-{N-hydroxyethyl-N-methylamino}ethoxy]-4,6-bis(trichloromethyl)-s-tri-
azine, and
2-[2-{N,N-diallylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triaz-
ine.
[0141] Particularly preferable ones among the triazine compounds
described above as examples are
2,4,6-tris(trichloromethyl)-s-triazine in terms of polymerization
activity and 2-phenyl-4,6-bis(trichloromethyl)-s-triazine,
2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, and
2-(4-biphenylyl)-4,6-bis(trichloromethyl)-s-triazine in terms of
storage stability. One of the above-mentioned triazine compounds
may be used or two or more of them may be used in mixture.
[0142] Examples of the copper compound used preferably as the
polymerization accelerator (H) include copper acetylacetonate,
copper (II) acetate, copper oleate, copper (II) chloride, and
copper (II) bromide.
[0143] Examples of the tin compound used as the polymerization
accelerator (H) include di-n-butyltin dimalate, di-n-octyltin
dimalate, di-n-octyltin dilaurate, and di-n-butyltin dilaurate.
Particularly preferable tin compounds are di-n-octyltin dilaurate
and di-n-butyltin dilaurate.
[0144] The vanadium compound used as the polymerization accelerator
(H) is preferably one of tetravalent and/or pentavalent vanadium
compounds. Examples of the tetravalent and/or pentavalent vanadium
compounds include compounds described in JP 2003-96122 A such as
divanadium (IV) tetroxide, vanadyl (IV) acetylacetonate, vanadyl
(IV) oxalate, vanadyl (IV) sulfate,
oxobis(1-phenyl-1,3-butanedionate)vanadium (IV),
bis(maltolato)oxovanadium (IV), vanadium (V) pentoxide, sodium
metavanadate (V), and ammonium metavanadate (V).
[0145] Examples of the halogen compound used preferably as the
polymerization accelerator (H) include
dilauryldimethylammoniumchloride,
lauryldimethylbenzylammoniumchloride,
benzyltrimethylammoniumchloride, tetramethylammoniumchloride,
benzyldimethylcetylammoniumchloride, and
dilauryldimethylammoniumbromide.
[0146] Examples of aldehydes used as the polymerization accelerator
(H) include terephthalaldehyde and a benzaldehyde derivative.
Examples of the benzaldehyde derivative include
dimethylaminobenzaldehyde, p-methyloxybenzaldehyde,
p-ethyloxybenzaldehyde, and p-n-octyloxybenzaldehyde. Among these,
from the viewpoint of curability, p-n-octyloxybenzaldehyde is used
preferably.
[0147] Examples of the thiol compound used as the polymerization
accelerator (H) include 3-mercaptopropyltrimethoxysilane,
2-mercaptobenzooxazol, decanethiol, and thiobenzoic acid.
[0148] Examples of sulfite used as the polymerization accelerator
(H) include sodium sulfite, potassium sulfite, calcium sulfite, and
ammonium sulfite.
[0149] Examples of bisulfate used as the polymerization accelerator
(H) include sodium bisulfate and potassium bisulfate.
[0150] Examples of the thiourea compound used as the polymerization
accelerator (H) include 1-(2-pyridyl)-2-thiourea, thiourea,
methylthiourea, ethylthiourea, N,N'-dimethylthiourea,
N,N'-diethylthiourea, N,N'-di-n-propylthiourea,
N,N'-dicyclohexylthiourea, trimethylthiourea, triethylthiourea,
tri-n-propylthiourea, tricyclohexylthiourea, tetramethylthiourea,
tetraethylthiourea, tetra-n-propylthiourea, and
tetracyclohexylthiourea.
[0151] The amount of polymerization accelerator (H) to be added in
the present invention is not particularly limited. However, from
the viewpoints of, for example, curability of the resultant
composition, it is preferable that 0.001 to 30 parts by mass of
polymerization accelerator (H) be contained with respect to 100
parts by mass of the whole amount of polymerizable monomer
components. When the amount of polymerization accelerator (H) to be
added is less than 0.001 part by mass, polymerization may not
proceed sufficiently and bond strength may be reduced. Therefore,
the amount is more preferably at least 0.05 part by mass and
further preferably at least 0.1 part by mass. On the other hand,
when the amount of polymerization accelerator (H) to be added
exceeds 30 parts by mass, in the case where the polymerization
initiator itself has low polymerization performance, sufficiently
high bond strength may not be obtained and further precipitation
from the composition may occur. Therefore, the amount is more
preferably 20 parts by mass or less and further preferably 10 parts
by mass or less.
[0152] Filler (I)
[0153] Preferably, a filler (I) further is mixed into a composition
of the present invention depending on the embodiment. Generally,
such fillers are divided roughly into organic fillers, inorganic
fillers, and organic-inorganic composite fillers. Examples of
materials for the organic fillers include polymethylmethacrylate,
polyethylmethacrylate, a methylmethacrylate-ethylmethacrylate
copolymer, cross-linked polymethylmethacrylate, cross-linked
polyethylmethacrylate, polyamide, polyvinyl chloride, polystyrene,
chloroprene rubber, nitrile rubber, an ethylene-vinyl acetate
copolymer, a styrene-butadiene copolymer, an acrylonitrile-styrene
copolymer, and an acrylonitrile-styrene-butadiene copolymer. These
may be used independently or a mixture of two or more of them may
be used. The shapes of the organic fillers are not particularly
limited, and particle sizes of the fillers to be used can be
selected appropriately. From the viewpoints of, for example,
handling ability and mechanical strength of the resultant
composition, the mean particle size of the organic fillers is
preferably 0.001 to 50 .mu.m and more preferably 0.001 to 10
.mu.m.
[0154] Examples of materials for the inorganic fillers include
quartz, silica, alumina, silica-titania, silica-titania-barium
oxide, silica-zirconia, silica-alumina, lanthanum glass,
borosilicate glass, soda glass, barium glass, strontium glass,
glass ceramics, aluminosilicate glass, barium boroaluminosilicate
glass, strontium boroaluminosilicate glass, fluoroaluminosilicate
glass, calcium fluoroaluminosilicate glass, strontium
fluoroaluminosilicate glass, barium fluoroaluminosilicate glass,
and strontium calcium fluoroaluminosilicate glass. Similarly, these
can be used independently or two or more of them can be used in
mixture. The shapes of the inorganic fillers are not particularly
limited and particle sizes of the fillers to be used can be
selected appropriately. From the viewpoints of, for example,
handling ability and mechanical strength of the resultant
composition, the mean particle size of the inorganic fillers is
preferably 0.001 to 50 .mu.m and more preferably 0.001 to 10
.mu.m.
[0155] Examples of the shapes of the inorganic fillers include
amorphous fillers and spherical fillers. From the viewpoint of
improving the mechanical strength of a composition, it is
preferable that spherical fillers be used as the inorganic fillers.
Furthermore, in the case of using the spherical fillers, when a
composition of the present invention is used as a dental composite
resin, there also is an advantage that a composition resin with
excellent surface smoothness is obtained. In this case, the
spherical fillers are fillers in which when a photograph thereof is
taken with a scanning electron microscope (hereinafter abbreviated
as SEM), particles observed within a unit field of view are rounded
and the mean uniformity obtained by dividing the particle size in
the direction orthogonal to the maximum diameter by the maximum
diameter is at least 0.6. The mean particle size of the spherical
fillers is preferably 0.1 to 5 .mu.m. When the mean particle size
is less than 0.1 .mu.m, the filling rate of the spherical fillers
in the composition decreases and thereby the mechanical strength
may be reduced. On the other hand, when the mean particle size
exceeds 5 .mu.m, the surface areas of the spherical fillers are
reduced and a cured product with high mechanical strength may not
be obtained.
[0156] The inorganic fillers may be used after the surfaces thereof
are treated beforehand with a known surface-treating agent such as
a silane coupling agent in order to adjust fluidity of the
composition as required. Examples of such a surface-treating agent
include vinyltrimethoxysilane, vinyltriethoxysilane,
vinyltrichlorosilane, vinyltri(.beta.-methoxyethoxy)silane,
.gamma.-methacryloyloxypropyltrimethoxysilane,
11-methacryloyloxyundecyltrimethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane,
.gamma.-mercaptopropyltrimethoxysilane, and
.gamma.-aminopropyltriethoxysilane.
[0157] The organic-inorganic composite fillers used in the present
invention can be obtained as follows. That is, a monomer compound
is added to the aforementioned inorganic filler beforehand, this is
made into a paste and is then polymerized, and thereafter this is
crushed. The organic-inorganic composite filler that can be used
is, for example, a TMPT filler (obtained by mixing
trimethylolpropane methacrylate with a silica filler, polymerizing
it, and then crushing it). The shape of the organic-inorganic
composite filler is not particularly limited, and the particle size
of the filler to be used can be selected appropriately. From the
viewpoints of, for example, handling ability and mechanical
strength of the resultant composition, the mean particle size of
the organic-inorganic composite filler is preferably 0.001 to 50
.mu.m and more preferably 0.001 to 10 .mu.m.
[0158] The amount of the filler (I) to be added in the present
invention is not particularly limited, but it is preferable that 1
to 2000 parts by mass of filler (I) be contained with respect to
100 parts by mass of the whole amount of polymerizable monomer
components. The preferable amount of filler (I) to be added varies
considerably depending on the embodiment to be employed.
Accordingly, preferable amounts of the filler (I) to be added
according to the respective embodiments are indicated together with
description of specific embodiments of the composition of the
present invention described later.
[0159] In addition, for example, a pH adjuster, polymerization
inhibitor, ultraviolet absorbent, thickening agent, colorant,
antibacterial agent, and flavor may be added to the composition of
the present invention within a range that does not inhibit the
effect of the present invention.
[0160] The composition of the present invention is used suitably as
a dental composition. This dental composition can be used for
dental materials such as a primer, bonding material, composite
resin, cement (resin cement, glass ionomer cement, and
resin-reinforced glass ionomer cement), pit and fissure sealant,
and denture base resin, and particularly, it is used suitably as a
primer, bonding material, composite resin, or cement. In this case,
the composition may be used as a two component type in which the
components of the composition are divided into two.
[0161] With respect to a dental material, generally, a dental
adhesive is used when a lost part of a tooth is filled or covered
with a restorative material. Typically, the dental adhesive is
allowed to act on dentin. In this case, when such a dental adhesive
is allowed to act on dentin, it is important for the dental
adhesive to have an decalcifying effect that allows a dentin
surface to be dissolved with an acidic component, a penetration
effect that allows a monomer component to penetrate into a collagen
layer of the dentin, and a curing effect that allows the monomer
component thus penetrated to solidify to form a hybrid layer
(hereinafter also referred to as a "resin-impregnated layer") with
collagen. Generally, a bonding system in which these three steps,
"decalcifying", "penetration", and "curing", are performed
separately is referred to as a "three-step bonding system".
Basically, a product used for the penetration step is a primer, and
a product used for the curing step is a bonding material.
[0162] Recently, in order to simplify the operation process, a
product that allows the decalcifying step and the penetration step
to be performed together in one step has been developed and has
been used practically. The product is referred to as a
"self-etching primer". Generally, the bonding system using a
self-etching primer and a bonding material is referred to as a
"two-step bonding system". The polymerizable monomer (A) used in
the present invention has at least two hydroxyl groups and has high
hydrophilicity. Therefore, it easily penetrates into a collagen
layer of dentin. Accordingly, a composition of the present
invention containing a polymerizable monomer (A) can be used as a
dental primer and also can be used as a dental self-etching
primer.
[0163] Preferably, the primer using a composition of the present
invention is a composition containing a polymerizable monomer (A),
bisacylphosphine oxide (B), polymerizable monomer (D) having an
acidic group, and solvent (F). Furthermore, an embodiment
containing a polymerization accelerator (H) also is used
preferably. The amounts of the above-mentioned (A) and (D) to be
added are preferably 10 to 99 parts by mass of (A) and 1 to 90
parts by mass of (D), more preferably 15 to 98 parts by mass of (A)
and 2 to 85 parts by mass of (D), and further preferably 20 to 97
parts by mass of (A) and 3 to 80 parts by mass of (D), in 100 parts
by mass of the whole amount of polymerizable monomer
components.
[0164] Furthermore, when penetrability of a primer composition into
a tooth structure (particularly dentin) is considered important, it
is preferable that further a polymerizable monomer (C) having one
polymerizable group and at least one hydroxyl group be contained.
When the primer composition contains (A), (C), and (D), the amounts
of respective components to be added are preferably 1 to 98 parts
by mass of (A), 1 to 90 parts by mass of (C), and 1 to 90 parts by
mass of (D), more preferably 3 to 90 parts by mass of (A), 5 to 85
parts by mass of (C), and 2 to 80 parts by mass of (D), and further
preferably 10 to 80 parts by mass of (A), 7 to 80 parts by mass of
(C), and 3 to 60 parts by mass of (D), in 100 parts by mass of the
whole amount of polymerizable monomer components.
[0165] When particularly the strength of the cured product of a
primer containing a composition of the present invention is
intended to be improved, a crosslinkable polymerizable monomer (E)
further may be added. When consideration is given to penetrability
into a tooth structure (particularly dentin), the above-mentioned
(E) is preferably an aliphatic compound-based bifunctional
polymerizable monomer, more preferably ethylene glycol
di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene
glycol di(meth)acrylate, or
1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, and further
preferably triethylene glycol di(meth)acrylate, or
1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane. The amount of
the above-mentioned (E) to be added is preferably 0 to 30 parts by
mass, more preferably 1 to 25 parts by mass, and further preferably
3 to 20 parts by mass, in 100 parts by mass of the whole amount of
polymerizable monomer components.
[0166] Furthermore, the amount of bisacylphosphine oxide (B) to be
contained is preferably 0.01 to 20 parts by mass, more preferably
0.05 to 15 parts by mass, and further preferably 0.1 to 10 parts by
mass, with respect to 100 parts by mass of the whole amount of
polymerizable monomer components. In the primer containing a
composition of the present invention, the use of bisacylphosphine
oxide (B) and polymerization initiator (G) in combination also is a
preferable embodiment. In this case, the amount of (G) to be
contained is preferably 0.001 to 20 parts by mass and more
preferably 0.1 to 10 parts by mass, with respect to 100 parts by
mass of the whole amount of polymerizable monomer components.
Furthermore, the additional use of a polymerization accelerator (H)
also is a preferable embodiment and particularly amines are used
suitably. In this case, the amount of (H) to be contained is
preferably 0.001 to 30 parts by mass, more preferably 0.05 to 20
parts by mass, and further preferably 0.1 to 10 parts by mass, with
respect to 100 parts by mass of the whole amount of polymerizable
monomer components.
[0167] In the primer containing a composition of the present
invention, since the polymerizable monomer (A) has at least two
hydroxyl groups in the molecule, hydrophilicity of the composition
of the present invention can be improved and thereby penetrability
into a collagen layer of dentin can be improved. Furthermore, it is
preferable that the solvent (F) be used in the form of a mixed
solvent of water (J) and an organic solvent (K). The amount of
water (J) to be contained in the mixed solvent is not particularly
limited but is preferably at least 10 mass %, more preferably at
least 30 mass %, and further preferably at least 50 mass %.
Moreover, the organic solvent (K) may not need to be added
depending on the embodiment. The amount of the aforementioned
solvent (F) to be added is preferably 5 to 4000 parts by mass,
preferably 10 to 3000 parts by mass, and further preferably 15 to
2000 parts by mass, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components. Furthermore, when the
solvent (F) is used in the form of a mixed solvent of water (J) and
the organic solvent (K), the amounts of the aforementioned (J) and
(K) to be added are preferably 4 to 2000 parts by mass of (J) and 1
to 2000 parts by mass of (K), more preferably 8 to 1500 parts by
mass of (J) and 2 to 1500 parts by mass of (K), and further
preferably 12 to 1000 parts by mass of (J) and 3 to 1000 parts by
mass of (K), with respect to 100 parts by mass of the whole amount
of polymerizable monomer components.
[0168] The composition of the present invention is used preferably
as a bonding material. Preferably, the bonding material in the
aforementioned "two-step bonding system" is a composition
containing the aforementioned polymerizable monomer (A),
bisacylphosphine oxide (B), and filler (I). More preferably, such a
composition further contains a polymerizable monomer (C) having one
polymerizable group and at least one hydroxyl group and/or
crosslinkable polymerizable monomer (E). Furthermore, an embodiment
containing a polymerization initiator (G) and polymerization
accelerator (H) also is used preferably. The amounts of respective
components to be added are preferably 1 to 99 parts by mass of (A),
0 to 90 parts by mass of (C), and 0 to 90 parts by mass of (E) and
more preferably 2 to 96 parts by mass of (A), 1 to 80 parts by mass
of (C), and 1 to 80 parts by mass of (E), in 100 parts by mass of
the whole amount of polymerizable monomer components. As in the
case of the above-mentioned (A) used in the present invention, the
use of a compound having at least two polymerizable groups allows a
cured product to have increased mechanical strength. From such a
viewpoint, the aforementioned (E) is more preferably a
polymerizable monomer having at least two polymerizable groups, and
from a viewpoint of obtaining a cured product with particularly
high strength, it is further preferable that the aforementioned (E)
contain an aromatic compound-based bifunctional polymerizable
monomer. The use of an aliphatic bifunctional polymerizable monomer
and aromatic compound-based bifunctional polymerizable monomer in
combination as the aforementioned (E) also is a preferable
embodiment.
[0169] Furthermore, the amount of (B) to be contained is preferably
0.01 to 20 parts by mass, more preferably 0.05 to 15 parts by mass,
and further preferably 0.1 to 10 parts by mass, with respect to 100
parts by mass of the whole amount of polymerizable monomer
components. In the bonding material containing a composition of the
present invention, the use of a bisacylphosphine oxide (B) and
polymerization initiator (G) in combination also is a preferable
embodiment. In this case, the amount of (G) to be contained is
preferably 0.001 to 20 parts by mass, more preferably 0.05 to 15
parts by mass, and further preferably 0.1 to 10 parts by mass, with
respect to 100 parts by mass of the whole amount of polymerizable
monomer components. Furthermore, the additional use of a
polymerization accelerator (H) also is a preferable embodiment, and
particularly amine is used suitably. In this case, the amount of
(H) to be contained is preferably 0.001 to 30 parts by mass, more
preferably 0.05 to 20 parts by mass, and further preferably 0.1 to
10 parts by mass, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components. Moreover, the amount of
filler (I) to be added is preferably 1 to 20 parts by mass, more
preferably 2 to 17 parts by mass, and further preferably 3 to 15
parts by mass, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components.
[0170] Recently, since there are demands for further simplification
in operations, products that allow three steps of "decalcifying",
"penetration", and "curing" to be performed together in one step
also have been developed and are referred to as "one-step bonding
systems". Two typical products of the bonding material used in such
a one-step bonding system are a bonding material in which two
separate liquids of liquid A and liquid B are mixed together
immediately before use and a bonding material that is provided in
the form of one liquid from the beginning and that is a so-called
one-component one-step bonding system. Among these, the
one-component type product further simplifies the process and
therefore has a greater advantage in use. When a composition of the
present invention is used as the bonding material of the
aforementioned one-component one-step bonding system, the
composition is preferably a composition containing a polymerizable
monomer (A), bisacylphosphine oxide (B), polymerizable monomer (D)
having an acidic group, filler (I), and solvent (F), and further
preferably, such a composition further contains a crosslinkable
polymerizable monomer (E). The amounts of respective components to
be added are preferably 1 to 98 parts by mass of (A), 1 to 90 parts
by mass (D), and 0 to 90 parts by mass of (E), more preferably 2 to
94 parts by mass of (A), 2 to 80 parts by mass of (D), and 2 to 80
parts by mass of (E), and further preferably 7 to 90 parts by mass
of (A), 3 to 70 parts by mass of (D), and 7 to 70 parts by mass of
(E), in 100 parts by mass of the whole amount of polymerizable
monomer components. In the one-component one-step bonding system,
since the "penetration" and "curing" are performed at one time, the
use of a polymerizable monomer having at least two hydroxyl groups
and at least two polymerizable groups like the aforementioned (A)
is of great significance.
[0171] In the one-component one-step bonding system, when
penetrability into a tooth structure (particularly dentin) is
considered important, it is preferable that a polymerizable monomer
(C) having one polymerizable group and at least one hydroxyl group
further be contained. When the one-component one-step bonding
system contains (A), (C), (D), and (E), the amounts of respective
components to be added are preferably 1 to 95 parts by mass of (A),
1 to 90 parts by mass of (C), 1 to 95 parts by mass of (D), and 3
to 97 parts by mass of (E), more preferably 3 to 90 parts by mass
of (A), 3 to 85 parts by mass of (C), 2 to 80 parts by mass of (D),
and 5 to 80 parts by mass of (E), and further preferably 5 to 80
parts by mass of (A), 5 to 80 parts by mass of (C), 3 to 60 parts
by mass of (D), and 8 to 70 parts by mass of (E), in 100 parts by
mass of the whole amount of polymerizable monomer components.
[0172] The amount of (B) to be contained is preferably 0.01 to 20
parts by mass, more preferably 0.05 to 15 parts by mass, and
further preferably 0.1 to 10 parts by mass, with respect to 100
parts by mass of the whole amount of polymerizable monomer
components. In the one-component one-step bonding system containing
a composition of the present invention, a combined use of a
bisacylphosphine oxide (B) and polymerization initiator (G) also is
a preferable embodiment. In this case, the amount of (G) to be
contained is preferably 0.001 to 20 parts by mass, more preferably
0.05 to 15 parts by mass, and further preferably 0.1 to 10 parts by
mass, with respect to 100 parts by mass of the whole amount of
polymerizable monomer components. Furthermore, an additional use of
a polymerization accelerator (H) also is a preferable embodiment
and particularly amine is used suitably. In this case, the amount
of (H) to be contained is preferably 0.001 to 30 parts by mass,
more preferably 0.05 to 20 parts by mass, and further preferably
0.1 to 10 parts by mass, with respect to 100 parts by mass of the
whole amount of polymerizable monomer components. Furthermore, the
amount of filler (I) to be added is preferably 1 to 20 parts by
mass, more preferably 1.5 to 15 parts by mass, and further
preferably 2 to 10 parts by mass, with respect to 100 parts by mass
of the whole amount of polymerizable monomer components.
[0173] The amount of solvent (F) to be added is preferably 6 to
4000 parts by mass, more preferably 12 to 3000 parts by mass, and
further preferably 15 to 2000 parts by mass, with respect to 100
parts by mass of the whole amount of polymerizable monomer
components. The one-component one-step bonding system needs to
perform all the processes of decalcifying, penetration, and curing
with one liquid in one step. Therefore, from the viewpoint that
penetrability is considered important, it is preferable that water
(J) be contained as the solvent (F). On the other hand, from the
viewpoint that curability is considered important, it is preferable
that the bonding system contain a suitable amount of crosslinkable
polymerizable monomer (E). From the viewpoints of increasing the
solubility of the aforementioned (E) and obtaining a uniform
solution, it is preferable that an organic solvent (K) be contained
as the aforementioned solvent (F). A more preferable embodiment is
the use of the solvent (F) in the form of a mixed solvent of water
(J) and an organic solvent (K). In such an embodiment, the amounts
of the aforementioned (J) and (K) to be added are preferably 2 to
2000 parts by mass of (J) and 4 to 2000 parts by mass of (K), more
preferably 4 to 1500 parts by mass of (J) and 8 to 1500 parts by
mass of (K), and further preferably 5 to 1000 parts by mass of (J)
and 10 to 1000 parts by mass of (K), with respect to 100 parts by
mass of the whole amount of polymerizable monomer components.
[0174] The composition of the present invention is used preferably
as composite resin. When the composition of the present invention
is used as composite resin, the composition is preferably one
containing a polymerizable monomer (A), bisacylphosphine oxide (B),
crosslinkable polymerizable monomer (E), and filler (I). Generally,
the composite resin is used in the form of filling a cavity after
the cavity is formed by cutting a site of caries incidence.
Thereafter, generally, the composite resin filling the cavity is
cured through photopolymerization. Therefore, the use of the
bisacylphosphine oxide (B), a photopolymerization initiator, has
significance. Furthermore, since the composite resin that has
filled the cavity and that has been cured as described above is
subjected to occlusal pressure inside an oral cavity, high
mechanical strength is required. Accordingly, the content of the
filler (I) in the composition is preferably 30 to 2000 parts by
mass and more preferably 50 to 1500 parts by mass, with respect to
100 parts by mass of the whole amount of polymerizable monomer
components. When the content of the filler (I) is less than 30
parts by mass, mechanical strength of the cured product may be
insufficient. On the other hand, when the content of the filler (I)
exceeds 2000 parts by mass, it may become difficult to disperse the
filler (I) uniformly throughout the whole amount of polymerizable
monomer components, which may result in a composition that is
insufficient in mechanical strength and handling ability. The
amounts of respective components to be added are preferably 1 to 99
parts by mass of (A) and 1 to 99 parts by mass of (E), more
preferably 10 to 95 parts by mass of (A) and 5 to 90 parts by mass
of (E), and further preferably 15 to 90 parts by mass of (A) and 10
to 85 parts by mass of (E), in 100 parts by mass of the whole
amount of polymerizable monomer components. Furthermore, the amount
of (B) to be contained is preferably 0.01 to 20 parts by mass, more
preferably 0.05 to 15 parts by mass, and further preferably 0.1 to
15 parts by mass, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components. The combined use of the
bisacylphosphine oxide (B) and polymerization initiator (G) also is
a preferable embodiment. In this case, the amount of (G) to be
contained is preferably 0.001 to 20 parts by mass, more preferably
0.05 to 15 parts by mass, and further preferably 0.1 to 10 parts by
mass, with respect to 100 parts by mass of the whole amount of
polymerizable monomer components. Further, the additional use of a
polymerization accelerator (H) also is a preferable embodiment, and
particularly amine is used suitably. In this case, the amount of
(H) to be contained is preferably 0.001 to 30 parts by mass, more
preferably 0.05 to 20 parts by mass, and further preferably 0.1 to
10 parts by mass, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components.
[0175] Since the polymerizable monomer (A) in the present invention
has both excellent curability and penetrability into a tooth
structure, it is preferable that it be used particularly as a
self-adhesive composite resin among composite resins. When the
composition of the present invention is used as a self-adhesive
composite resin, it is preferable that the composition contain a
polymerizable monomer (A), bisacylphosphine oxide (B),
polymerizable monomer (D) having an acidic group, crosslinkable
polymerizable monomer (E), and filler (I). The amounts of
respective components to be added are preferably 1 to 95 parts by
mass of (A), 1 to 90 parts by mass of (D), and 4 to 90 parts by
mass of (E), more preferably 5 to 80 parts by mass of (A), 2 to 85
parts by mass of (D), and 6 to 85 parts by mass of (E), and further
preferably 10 to 80 parts by mass of (A), 3 to 80 parts by mass of
(D), and 8 to 80 parts by mass of (E), in 100 parts by mass of the
whole amount of polymerizable monomer components. Furthermore, when
the penetrability into a tooth structure (particularly dentin) is
considered important, it is preferable that the composition further
contain a polymerizable monomer (C) having one polymerizable group
and at least one hydroxyl group. When the self-adhesive composite
resin contains (A), (C), (D), and (E), the amounts of respective
components to be added are preferably 1 to 95 parts by mass of (A),
1 to 90 parts by mass of (C), 1 to 90 parts by mass of (D), and 3
to 90 parts by mass (E), more preferably 3 to 90 parts by mass of
(A), 3 to 85 parts by mass of (C), 2 to 85 parts by mass of (D),
and 5 to 85 parts by mass of (E), and further preferably 5 to 80
parts by mass of (A), 5 to 70 parts by mass of (C), 3 to 60 parts
by mass of (D), and 8 to 70 parts by mass of (E), in 100 parts by
mass of the whole amount of polymerizable monomer components. With
respect to the amounts of bisacylphosphine oxide (B) and filler (H)
to be added, the same amounts as those used in the aforementioned
general composite resin can be employed. Furthermore, in the same
manner as in the case of the aforementioned general composite
resin, the combined use of the bisacylphosphine oxide (B),
polymerization initiator (G), and polymerization accelerator (H)
also is a preferable embodiment. The amounts of the aforementioned
(B), (G), and (H) to be added are as described above. Moreover,
when particularly the penetrability into a tooth structure is
considered important, it also is possible to add a solvent (F), and
it is further preferable that the solvent (F) contain water (J).
The amount of solvent (F) to be added is preferably 0 to 15 parts
by mass and more preferably 1 to 10 parts by mass, with respect to
100 parts by mass of the whole amount of polymerizable monomer
components.
[0176] Furthermore, the use of a composition of the present
invention as a dental cement also is one of preferable embodiments.
Examples of preferable cements include a resin cement, glass
ionomer cement, and resin-reinforced glass ionomer cement. When the
composition of the present invention is used as a resin cement, the
composition is preferably one containing a polymerizable monomer
(A), bisacylphosphine oxide (B), crosslinkable polymerizable
monomer (E), polymerization accelerator (H), filler (I), and water
(J) to serve as a solvent (F). Such a composition further can
contain a polymerizable monomer (D) having an acidic group. The
dental cement is used suitably as, for example, a luting material
that is used in fixing a metal or ceramics dental crown restorative
material, which is referred to as an "inlay" or "crown", to a
tooth. As in the case of the aforementioned (A) used in the present
invention, when at least two polymerizable groups are included, the
resultant cured product has increased mechanical strength and can
withstand, for example, occlusal pressure. From such a viewpoint,
it is more preferable that the aforementioned (E) be a
polymerizable monomer having at least two polymerizable groups.
Furthermore, in the case of the form of usage as described above,
since many of the dental crown restorative materials have optical
opacity, it is not easy to cure the cement by only
photopolymerization. Therefore, it is preferable that a chemical
polymerization initiator be used as the aforementioned (G).
Furthermore, when polymerization is performed by using a chemical
polymerization initiator, in order to improve the reactivity
thereof, the use of amines and/or sulfinic acid and salt thereof as
the aforementioned (H) is preferable and the simultaneous use of
amines and sulfinic acid and salt thereof is more preferable. The
filler (I) used is not particularly limited.
[0177] When the cement is intended to be provided with a property
of sustained-release of fluoride, it is preferable that at least
one selected from the group consisting of fluoroaluminosilicate
glass, calcium fluoroaluminosilicate glass, strontium
fluoroaluminosilicate glass, barium fluoroaluminosilicate glass,
and strontium calcium fluoroaluminosilicate glass be used as the
filler (I), and it is more preferable that fluoroaluminosilicate
glass and/or barium fluoroaluminosilicate glass be used as the
filler (I). On the other hand, when the cement is intended to be
provided with radiopacity, it is preferable that at least one
selected from the group consisting of barium glass, strontium
glass, barium boroaluminosilicate glass, strontium
boroaluminosilicate glass, strontium fluoroaluminosilicate glass,
and barium fluoroaluminosilicate glass be used as the filler (I),
and it is more preferable that barium glass and/or barium
fluoroaluminosilicate glass be used as the filler (I).
[0178] When a chemical polymerization initiator is used, from the
viewpoint of storage stability, it is preferable that the
aforementioned (G) and (H) be stored in separate containers,
respectively. That is, in a preferred embodiment, the resin cement
is used in the form of a two component type. In a more preferred
embodiment, the resin cement is used in the form of two paste type.
Preferably, the respective pastes are stored while being separated
from each other, the two pastes are mixed together immediately
before use, and thereby chemical polymerization is allowed to
proceed to cure the mixture. The aforementioned pastes each are
prepared by mixing a liquid component of, for example,
polymerizable monomer with a filler (I) (powder) together.
Furthermore, when sulfinic acid and salt thereof are used as the
aforementioned (H), from the viewpoint of storage stability, it is
preferable that the aforementioned (D) and (H) be stored in
separate containers, respectively. Suppose that the aforementioned
two pastes are referred to as a paste A and a paste B,
respectively, an embodiment in which the paste A contains (A), (D),
(B), (G), and (I) and the paste B contains (A), (H), and (I) is
used particularly suitably.
[0179] When the composition of the present invention is used as a
dental cement, the amounts of respective components to be added are
not particularly limited. However, in 100 parts by mass of the
whole amount of polymerizable monomer components, the composition
contains preferably 1 to 98 parts by mass of (A), 0 to 90 parts by
mass of (C), 1 to 90 parts by mass of (D), and 1 to 90 parts by
mass of (E), and more preferably 2 to 96 parts by mass of (A), 0 to
85 parts by mass of (C), 2 to 85 parts by mass of (D), and 2 to 85
parts by mass of (E). When consideration is given to obtaining a
suitable setting time, the amounts of the aforementioned (B), (G),
and (H) to be added are preferably 0.01 to 20 parts by mass of (B),
0.001 to 20 parts by mass of (G), and 0.001 to 30 parts by mass of
(H) and more preferably 0.05 to 15 parts by mass of (B), 0.05 to 15
parts by mass of (G), and 0.05 to 20 parts by mass of (H), with
respect to 100 parts by mass of the whole amount of polymerizable
monomer components.
[0180] Furthermore, with respect to 100 parts by mass of the whole
amount of polymerizable monomer components, the content of (I) is
preferably 30 to 2000 parts by mass and more preferably 50 to 1500
parts by mass. When the content of (I) is less than 30 parts by
mass, mechanical strength of the cured product may be insufficient.
On the other hand, in the case where the content of (I) exceeds
2000 parts by mass, when the resin cement is used as a
two-paste-type cement, which is a preferred embodiment, the pastes
lack fluidity, which makes it difficult to carry out sufficient
mixing, and therefore the cured product may have reduced strength.
The composition of the present invention is used preferably as a
glass ionomer cement and more preferably as a resin-reinforced
glass ionomer cement. The glass ionomer cement is typically one in
which an inorganic filler such as fluoroaluminosilicate glass and
polyalkenoic acid such as polyacrylic acid are reacted with each
other through an acid-base reaction to be cured. Conceivably, the
polyacrylic acid interacts with calcium contained in hydroxyapatite
composing a tooth structure and thereby a bonding function is
exhibited. When a composition of the present invention is used as a
glass ionomer cement, particularly preferably as a resin-reinforced
glass ionomer cement, the composition is preferably one containing
(A), (B), (H), (I), (F), and polyalkenoic acid, and more preferably
one containing (A), (E), (B), (H), (I), (F), and polyalkenoic acid,
one containing (A), (C), (B), (H), (I), (F), and polyalkenoic acid,
or one containing (A), (C), (E), (B), (H), (I), (F), and
polyalkenoic acid. Such compositions further can contain (D).
[0181] The polymerizable monomer (C) having one polymerizable group
and at least one hydroxyl group to be used is not particularly
limited. As described later, from the viewpoint that an acid-base
reaction is allowed to proceed smoothly, it is preferable that the
solvent (F) contain water (J). Therefore, from the viewpoints of
maintaining the uniformity of the composition and obtaining
consistent performance, it is more preferable that a monomer with
high affinity for water (J) be used as the aforementioned (C). Such
a monomer with high affinity for water (J) is preferably
2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate,
glycerol mono(meth)acrylate, or erythritol mono(meth)acrylate and
particularly preferably 2-hydroxyethylmethacrylate.
[0182] The crosslinkable polymerizable monomer (E) to be used is
not particularly limited, but as described above, the use of a
monomer with high affinity for water (J) as the aforementioned (E)
is more preferable from the viewpoints of maintaining the
uniformity of the composition and obtaining consistent performance.
In terms of a balance between such affinity for water (J) and the
mechanical strength of the cured product, the aforementioned (E) is
preferably an aliphatic compound-based bifunctional polymerizable
monomer and more preferably triethylene glycol di(meth)acrylate,
polyethylene glycol di(meth)acrylate, neopentyl glycol
di(meth)acrylate,
1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, or
2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl) dimethacrylate
(commonly known as "UDMA").
[0183] The aforementioned polyalkenoic acid is a polymer of
unsaturated monocarboxylic acid or unsaturated dicarboxylic acid.
Specific examples of the polyalkenoic acid include homopolymers of,
for example, acrylic acid, methacrylic acid, 2-chloroacrylic acid,
2-cyanoacrylic acid, aconitic acid, mesaconic acid, maleic acid,
itaconic acid, fumaric acid, glutaconic acid, citraconic acid, and
utraconic acid, or copolymers of these unsaturated carboxylic acids
and monomers copolymerizable therewith. In the case of the
copolymers, the ratio of the unsaturated carboxylic acid unit is
preferably at least 50 mol % with respect to the total structure
unit. An ethylenically unsaturated polymerizable monomer is
preferable as the copolymerizable monomer, and examples thereof
include styrene, acrylamide, acrylonitrile, methyl methacrylate,
acrylic acid salts, vinyl chloride, allyl chloride, vinyl acetate,
and 1,1,6-trimethylhexamethylene dimethacrylate ester. Among those
polyalkenoic acids, a homopolymer or copolymer of acrylic acid or
maleic acid is preferable. When these polyalkenoic acids have a
weight-average molecular weight of less than 5,000, the cured
product of the dental cement composition may have reduced strength
and poor durability. On the other hand, when it has a
weight-average molecular weight exceeding 40,000, it may have high
consistency during mixing of the dental cement composition and
therefore may have lower operability. Accordingly, a preferable
weight-average molecular weight of the polyalkenoic acid is 5,000
to 40,000.
[0184] From the viewpoints of curability in the acid-base reaction
and the property of sustained-release of fluoride of the
composition, the filler (I) to be used is preferably at least one
selected from the group consisting of fluoroaluminosilicate glass,
calcium fluoroaluminosilicate glass, strontium
fluoroaluminosilicate glass, barium fluoroaluminosilicate glass,
and strontium calcium fluoroaluminosilicate glass, and more
preferably fluoroaluminosilicate glass and/or barium
fluoroaluminosilicate glass.
[0185] Furthermore, the solvent (F) to be used is not particularly
limited. However, from the viewpoint that an acid-base reaction is
allowed to proceed smoothly, it is preferable that the solvent (F)
contain water (J). When a mixed solvent of water (J) and an organic
solvent (K) is used as the solvent (F), the content of water (J) in
the mixed solvent is preferably at least 50 mass %, more preferably
at least 70 mass %, and further preferably at least 90 mass %. In
an embodiment in which particularly progress of the acid-base
reaction is considered important, it is particularly preferable
that the solvent (F) consist substantially of water (J) alone.
[0186] When a composition of the present invention is used as a
glass ionomer cement, particularly preferably as a resin-reinforced
glass ionomer cement, the amounts of respective components to be
added are not particularly limited. When the composition contains
(A) and (C), it contains preferably 1 to 99 parts by mass of (A), 1
to 90 parts by mass of (C), and 0 to 50 parts by mass of (D) and
more preferably 2 to 95 parts by mass of (A), 5 to 85 parts by mass
of (C), and 0 to 30 parts by mass of (D), in 100 parts by mass of
the whole amount of polymerizable monomer components. When the
composition contains (A) and (E), it contains preferably 1 to 99
parts by mass of (A), 1 to 90 parts by mass of (E), and 0 to 50
parts by mass of (D) and more preferably 2 to 95 parts by mass of
(A), 5 to 98 parts by mass of (E), and 0 to 30 parts by mass of
(D), in 100 parts by mass of the whole amount of polymerizable
monomer components. Furthermore, when the composition contains (A),
(C), and (E), it contains preferably 1 to 98 parts by mass of (A),
1 to 90 parts by mass of (C), 1 to 90 parts by mass of (E), and 0
to 50 parts by mass of (D) and more preferably 2 to 90 parts by
mass of (A), 5 to 85 parts by mass of (C), 5 to 85 parts by mass of
(E), and 0 to 30 parts by mass of (D), in 100 parts by mass of the
whole amount of polymerizable monomer components.
[0187] The combined use of bisacylphosphine oxide (B) and
polymerization initiator (G) also is a preferable embodiment. In
this case, the content of (G) is preferably 0.001 to 20 parts by
mass, more preferably 0.05 to 15 parts by mass, and further
preferably 0.1 to 10 parts by mass, with respect to 100 parts by
mass of the whole amount of polymerizable monomer components.
Furthermore, the additional use of a polymerization accelerator (H)
also is a preferable embodiment, and particularly amine is used
suitably. In this case, the content of (H) is preferably 0.001 to
30 parts by mass, more preferably 0.05 to 20 parts by mass, and
further preferably 0.1 to 10 parts by mass, with respect to 100
parts by mass of the whole amount of polymerizable monomer
components. Moreover, the content of (I) is preferably 30 to 2000
parts by mass and more preferably 50 to 1500 parts by mass, with
respect to 100 parts by mass of the whole amount of polymerizable
monomer components. When the content of (I) is less than 30 parts
by mass, mechanical strength of the cured product may be
insufficient. On the other hand, when the content of (I) exceeds
2000 parts by mass, the composition paste has lower fluidity, which
makes sufficient mixing difficult, and therefore the acid-base
reaction may not proceed smoothly. As a result, the cured product
may have reduced strength.
[0188] With respect to 100 parts by mass of the whole amount of
polymerizable monomer components, the content of solvent (F) is
preferably 7 to 500 parts by mass, more preferably 10 to 300 parts
by mass, and further preferably 20 to 100 parts by mass. When the
solvent (F) is contained in such ranges, the acid-base reaction can
proceed smoothly, and the resultant cured product has excellent
mechanical strength and excellent adhesive properties to a tooth
structure.
[0189] With respect to 100 parts by mass of the whole amount of
polymerizable monomer components, the content of the aforementioned
polyalkenoic acid is preferably 1 to 200 parts by mass, more
preferably 5 to 100 parts by mass, and further preferably 10 to 50
parts by mass. When the polyalkenoic acid is contained in such
ranges, curing through the acid-base reaction proceeds smoothly and
decay of the resultant cured product inside an oral cavity by, for
example, hydrolysis can be diminished.
[0190] As described above, since curing of a glass ionomer cement
occurs through progress of an acid-base reaction, from the
viewpoint of storage stability, it is preferable that a basic
filler (I) and polyalkenoic acid be packed in separate containers
and be used after being mixed immediately before use. The
preferable types of products to be employed include a so-called
powder-liquid type, but from the viewpoint of improving handling
ability, the form of so-called two past-type glass ionomer cement
containing two types of pastes is more preferable. In the case
where the type of product is the two paste type, when the
aforementioned two pastes are referred to as a paste A and a paste
B, respectively, an embodiment is preferable in which the paste A
contains (A), (B), (F), (I), and polyalkenoic acid and the paste B
contains (C) and (I). Furthermore, an embodiment in which the paste
A contains (A), (B), (F), (I), and polyalkenoic acid and the paste
B contains (E) and (I) also is used preferably. In addition, an
embodiment in which the paste A contains (E), (B), (I), and
polyalkenoic acid and the paste B contains (A), (G), (I), and (F)
also is used preferably. In this case, when particularly adhesive
properties are considered important, it is preferable that the
paste A further contain (D), and from the similar viewpoint, it
also is preferable that the paste B further contain (C). In all of
the embodiments, since the paste A contains polyalkenoic acid, it
is preferable that at least one selected from the group consisting
of fluoroaluminosilicate glass, calcium fluoroaluminosilicate
glass, strontium fluoroaluminosilicate glass, barium
fluoroaluminosilicate glass, and strontium calcium
fluoroaluminosilicate glass be used as the filler (I) contained in
the paste B, and it is more preferable that fluoroaluminosilicate
glass and/or barium fluoroaluminosilicate glass be used as the
filler (I). On the other hand, the filler (I) contained in the
paste A to be used is preferably one that exhibits no reactivity
with polyalkenoic acid, and particularly preferably quartz.
[0191] These dental materials can be prepared and used according to
a conventional method. These dental materials exhibit excellent
bond strength and bond durability with respect to a tooth structure
(particularly dentin). Hereinafter, the present invention is
described in further detail using examples but is not limited
thereto.
Example 1
Application to One-Step Bonding System (One-Component Bonding
Material)
(1) Production of One-Component Bonding Material
[0192] Respective components were mixed together at an ordinary
temperature and thereby a one-component bonding material
composition was produced. The composition thereof is indicated in
Table 1. The bond strength with respect to bovine teeth dentin was
measured according to the following procedure.
TABLE-US-00001 TABLE 1 One-Component Bonding Material Compositions
and Bonding Evaluation Results Ex. Ex. Ex. Ex. Ex. Ex. Ex. C. Ex.
C. Ex. C. Ex. Components 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-1 1-2 1-3
Polymerizable monomer EDMA 15 15 15 15 15 (A) XDMA 15 15 SDMA 15 15
MDMA 15 Polymerizable monomer #801 for comparison with (A) GDMA
Polymerizable monomer HEMA 15 15 15 15 15 15 15 15 15 15 (C) having
one polymerizable group and at least one hydroxyl group
Polymerizable monomer MDP 10 10 10 10 10 10 10 10 10 10 (D) having
acidic group Crosslinkable Bis-GMA 30 30 30 30 30 30 30 30 30 30
polymerizable monomer (E) Solvent (F) Distilled 15 15 15 15 15 15
15 15 15 15 water Ethanol 15 15 15 15 15 15 15 15 15 15
Polymerization initiator BAPO-1 5 5 5 5 0.5 3 (B) BAPO-2 5
Polymerization initiator TMDPO 5 5 5 (G) CQ 1 Polymerization DBB
0.9 accelerator (H) Filler (I) Inorganic 5 5 5 5 5 5 5 5 5 5 filler
1 Bond strength with After 24 24.7 22.2 22.3 23.9 22.5 22.1 24.3
18.7 16.5 17.5 respect to dentin (MPa) hours After 24.8 21.0 21.2
23.5 22.9 21.1 24.5 19.0 18.2 18.4 thermal cycles load C. Ex. C.
Ex. C. Ex. C. Ex. C. Ex. C. Ex. C. Ex. Components 1-4 1-5 1-6 1-7
1-8 1-9 1-10 Polymerizable monomer EDMA 15 15 (A) XDMA SDMA MDMA 15
Polymerizable monomer #801 15 for comparison with (A) GDMA 15 15
Polymerizable monomer HEMA 15 15 15 30 15 15 15 (C) having one
polymerizable group and at least one hydroxyl group Polymerizable
monomer MDP 10 10 10 10 10 10 10 (D) having acidic group
Crosslinkable Bis-GMA 30 30 30 30 polymerizable monomer (E) Solvent
(F) Distilled 15 15 15 15 15 15 15 water Ethanol 15 15 15 15 15 15
15 Polymerization initiator BAPO-1 5 5 5 (B) BAPO-2 Polymerization
initiator TMDPO 5 5 5 (G) CQ 2 2 Polymerization DBB 1 1 accelerator
(H) Filler (I) Inorganic 5 5 5 5 5 5 5 filler 1 Bond strength with
After 24 19.9 18.5 18.7 15.7 15.2 15.8 12.8 respect to dentin (MPa)
hours After 19.5 18.6 18.7 16.1 14.8 14.6 9.8 thermal cycles load
(The amounts of respective components added each are indicated in
the unit of parts by mass.) EDMA: erythritol dimethacrylate
[1,4-bis(methacryloyloxy)-2,3-butanediol] XDMA: xylitol
dimethacrylate [1,5-bis(methacryloyloxy)-2,3,4-pentanetriol] SDMA:
sorbitol dimethacrylate
[1,6-bis(methacryloyloxy)-2,3,4,5-hexanetetraol] MDMA: mannitol
dimethacrylate (3,4-di-O-methacryloyl-D-mannitol) #801:
1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane GDMA: glycerol
dimethacrylate [polymerizable monomer for comparative examples that
does not correspond to polymerizable monomer (A)] MDP:
10-methacryloyloxydecyldihydrogenphosphate HEMA:
2-hydroxyethylmethacrylate Bis-GMA:
2,2-bis[4-(3-methacryloyloxy)-2-hydroxypropoxyphenyl]-propane
(bisphenol A diglycidyl methacrylate) BAPO-1:
bis-(2,4,6-trimethylbenzoyl)phenylphosphine oxide BAPO-2:
bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide
TMDPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide CQ:
camphorquinone DBB: N,N-dimethylaminobenzoic acid n-butoxyethyl
ester Inorganic filler 1: "R972" manufactured by Japan Aerosil
Inc.
[0193] MDMA is a new compound and it was synthesized by the
following method.
[0194] Reference Example Synthesis of MDMA
[0195] (i) Synthesis of 1,2 :5,6-Di-O-isopropylidene-3,
4-di-O-methacryloyl-D-mannitol
[0196] After 700 mL of anhydrous pyridine was added to a 2 L
separable flask equipped with a condenser tube, 65 g of
1,2:5,6-Di-O-isopropylidene-D-mannitol (manufactured by Wako Pure
Chemical Industries, Ltd.) was added into the flask gradually and
was dissolved completely. An ice bath was set for the reaction
system and the reaction system was cooled to 0.degree. C.
Subsequently, while the temperature of the reaction system was
maintained around 0.degree. C. and the reaction system was stirred,
60 g of methacryloyl chloride (manufactured by Wako Pure Chemical
Industries, Ltd.) was dropped into the reaction system in a
nitrogen atmosphere using a dropping funnel over approximately one
hour. The dropping funnel was replaced by a glass stopper, and the
reaction system was heated to 70.degree. C. using an oil bath. This
heating was continued for eight hours. After completion of heating,
the oil bath was removed and the reaction system was then cooled to
room temperature. Subsequently, the reaction system was poured into
a beaker containing 1 L of ice water and thereby the reaction was
stopped. After the reaction was stopped, extraction was performed
five times using 1500 mL of diethyl ether. Thereafter, the
resultant organic layer was subjected to vacuum concentration using
an evaporator and thus an oily material was obtained. The oily
material was purified using silica gel column chromatography
(diluents: hexane:diethyl ether=7:3). After concentration, hexane
was added and thereby recrystallization was carried out. Thus, a
target compound was obtained. The yield amount was 36.3 g, and the
yield rate was 37%.
[0197] .sup.1H-NMR (400 MHz, CDCl.sub.3, .delta.) 1.31 (s, 6H),
1.36 (s, 6H), 1.96 (s, 6H), 3.85-3.96 (m, 4H), 4.21-4.27 (m, 2H),
5.43 (dd, 2H), 5.64 (s, 2H), 6.15 (s, 2H) (ppm).
[0198] .sup.13C-NMR (100 MHz, CDCl.sub.3, .delta.) 18.2, 25.1,
26.3, 65.5, 71.6, 74.7, 109.3, 126.6, 135.6, 166.0 (ppm).
(ii) Synthesis of MDMA (3,4-di-O-methacryloyl-D-mannitol)
[0199] 540 mL of acetic acid and 180 mL of water were added to a 2
L round-bottom flask. While the resultant acetic acid aqueous
solution was stirred, 18 g of
1,2:5,6-Di-O-isopropylidene-3,4-di-O-methacryloyl-D-mannitol
synthesized above was added gradually thereto and was dissolved
completely. The solution thus prepared was stirred for 18 hours,
with the temperature thereof being maintained at 25.degree. C.
After completion of stirring, the solution was subjected to vacuum
concentration using an evaporator and thus an oily material was
obtained. The oily material was purified using silica gel column
chromatography (diluent:ethyl acetate 100%) and was concentrated.
As a result, white crystals were precipitated. It was confirmed by
NMR that these crystals were a target compound. The yield amount
was 8.7 g and the yield rate was 60%.
[0200] .sup.1H-NMR (400 MHz, CD.sub.3OD, .delta.) 1.84 (s, 6H),
3.39 (dd, 2H), 3.51 (dd, 2H), 3.59-3.66 (m, 2H), 5.28 (d, 2H), 5.56
(s, 2H), 6.03 (s, 2H) (ppm).
[0201] .sup.13C-NMR (100 MHz, CD.sub.3OD, .delta.) 18.4, 64.2,
71.6, 73.1, 126.8, 137.4, 167.9 (ppm).
(2) Method of Evaluating Bonding to Bovine Teeth Dentin
[0202] The labial surface of a bovine mandibular incisor was ground
with #80 silicon carbide paper (manufactured by Nihon Kenshi Co.,
Ltd.) under running water, and thereby a sample with an exposed
flat surface of dentin was obtained. The sample thus obtained
further was ground with #1000 silicon carbide paper (manufactured
by Nihon Kenshi Co., Ltd.) under running water. After completion of
grinding, water on the surface was air-blown to be dried. An
adhesive tape with a thickness of about 150 .mu.m having a circular
hole whose diameter was 3 mm was attached to the smooth surface
that had been dried and thereby the adhesive area was defined.
[0203] Each one-component bonding material composition produced
above was applied into the above-mentioned circular hole using a
brush and was then allowed to stand for 20 seconds. Thereafter, the
surface thereof was air-blown with a dental air syringe and thereby
the one-component bonding material composition thus applied was
dried until it lost fluidity. Subsequently, it was irradiated with
light using a dental visible light unit "JET LITE 3000"
(manufactured by J. Morita USA) for 10 seconds. Thus, the
one-component bonding material composition that had been applied
was cured.
[0204] A dental filling composite resin (manufactured by Kuraray
Medical Inc., "CLEARFILAP-X" (trade name, registered trademark))
was applied to the surface of each resultant cured product of the
one-component bonding material compositions, and it was then
covered with a mold release film (polyester). Next, slide glass was
placed on the mold release film to press it, and thereby the
surface of the applied composite resin was smoothed. Subsequently,
the composite resin was irradiated with light for 20 seconds using
the aforementioned unit "JET LITE 3000" through the mold release
film. Thus, the composite resin was cured.
[0205] One end face (circular section) of a stainless-steel
cylindrical rod (with a diameter of 5 mm and a length of 1.5 cm)
was bonded to the surface of the resultant cured product of the
dental filling composite resin using a commercially available
dental resin cement (manufactured by Kuraray Medical Inc.,
"PANAVIA21" (trade name)). After bonding, this sample was allowed
to stand still at room temperature for 30 minutes and was then
immersed in distilled water. The resultant sample that had been
immersed in distilled water was allowed to stand still for 24 hours
inside a thermostat whose temperature was maintained at 37.degree.
C. Thus, a bonding test sample was produced. Ten bonding test
samples were produced in total, and all the samples that had been
immersed in distilled water were allowed to stand still for 24
hours inside the thermostat whose temperature was maintained at
37.degree. C. With respect to five samples out of the ten samples,
in order to evaluate the bond strength in the early bonding stage,
the bond strength was measured immediately after they were allowed
to stand still for 24 hours. With respect to the other five
samples, in order to evaluate bond durability, bond strength was
measured after 4000 thermal cycles had been performed, with one
cycle being a process for further immersing each sample in
4.degree. C. cold water and 60.degree. C. warm water alternately
for one minute.
(3) Measurement of Bond Strength
[0206] The tensile bond strengths of the above-mentioned five
bonding test samples were measured with a universal testing machine
(manufactured by Instron Inc.), with the crosshead speed being set
at 2 mm/min, and the average value thereof was taken as tensile
bond strength. The results thus obtained are indicated together in
Table 1.
Example 2
Application to Two-Step Bonding System (Two-Component Bonding
Material)
(1) Production of Primer Using Polymerizable Composition Containing
Polymerizable Monomer (A)
[0207] The respective components were mixed together at ordinary
temperature and thereby primer compositions were produced. The
compositions thereof are indicated in Table 2.
TABLE-US-00002 TABLE 2 Primer Compositions and Bonding Evaluation
Results Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Components 2-1 2-2 2-3
2-4 2-5 2-6 2-7 2-8 2-9 Polymerizable EDMA 35 35 35 35 35 monomer
(A) XDMA 35 SDMA 35 MDMA 35 35 Polymerizable GDMA monomer for ErMA
comparison with (A) Polymerizable MDP 20 20 20 20 20 20 20 20 20
monomer (D) having acidic group Polymerizable HEMA 35 35 35 35 35
35 35 35 35 monomer (C) having one polymerizable group and at least
one hydroxyl group Crosslinkable #801 10 10 10 10 10 10 10 10 10
polymerizable monomer (E) Solvent (F) Distilled water 50 50 50 50
50 50 50 50 50 Ethanol 50 50 50 50 50 50 50 50 50 Polymerization
BAPO-1 0.8 0.8 0.8 0.8 0.1 3 3 initiator (B) BAPO-2 0.8 0.8
Polymerization TMDPO initiator (G) CQ 0.8 Polymerization DBB 1
accelerator (H) Bond strength with After 24 hours 26.6 25.7 25.6
26.7 26.4 26.8 25.1 25.6 25.1 respect to dentin After thermal 26.9
25.8 25.8 26.5 26.3 25.5 24.9 26.7 25.7 (MPa) cycles load C. Ex. C.
Ex. C. Ex. C. Ex. C. Ex. C. Ex. C. Ex. Components 2-1 2-2 2-3 2-4
2-5 2-6 2-7 Polymerizable EDMA 35 35 35 monomer (A) XDMA 35 SDMA
MDMA Polymerizable GDMA 35 monomer for ErMA 35 comparison with (A)
Polymerizable MDP 20 20 20 20 20 20 20 monomer (D) having acidic
group Polymerizable HEMA 35 35 35 35 70 35 35 monomer (C) having
one polymerizable group and at least one hydroxyl group
Crosslinkable #801 10 10 10 10 10 10 10 polymerizable monomer (E)
Solvent (F) Distilled water 50 50 50 50 50 50 50 Ethanol 50 50 50
50 50 50 50 Polymerization BAPO-1 0.8 0.8 0.8 initiator (B) BAPO-2
Polymerization TMDPO 0.8 0.8 3 initiator (G) CQ 0.8 Polymerization
DBB 1 accelerator (H) Bond strength with After 24 hours 23.6 22.6
23.8 23.9 22.2 20.2 19.9 respect to dentin After thermal 23.9 22.5
24.0 22.4 21.9 20.9 20.1 (MPa) cycles load ErMA: pentaerythritol
dimethacrylate (The amounts of respective components added each are
indicated in the unit parts by mass, and the respective
abbreviations have the same meanings as described above.)
(2) Method of Evaluating Bonding to Bovine Teeth Dentin
[0208] The labial surface of a bovine mandibular incisor was ground
with #80 silicon carbide paper (manufactured by Nihon Kenshi Co.,
Ltd.) under running water, and thereby a sample with an exposed
flat surface of dentin was obtained. The sample thus obtained
further was ground with #1000 silicon carbide paper (manufactured
by Nihon Kenshi Co., Ltd.) under running water. After completion of
grinding, water on the surface was air-blown to be dried. An
adhesive tape with a thickness of about 150 .mu.m having a circular
hole whose diameter was 3 mm was attached to the smooth surface
that had been dried and thereby the adhesive area was defined.
[0209] Each primer produced above was applied into the
above-mentioned circular hole using a brush and was then allowed to
stand for 20 seconds. Thereafter, the surface thereof was air-blown
and thereby the primer thus applied was dried until it lost
fluidity. Next, the bonding material having a composition indicated
in Table 3 was applied over the tooth surface where the primer had
been applied and dried. Subsequently, it was irradiated with light
using a dental visible light unit "JET LITE 3000" (manufactured by
J. Morita USA) for 10 seconds. Thus, the primer and bonding
material that had been applied were cured.
[0210] A dental filling composite resin (manufactured by Kuraray
Medical Inc., "CLEARFIL AP-X" (trade name, registered trademark))
was applied to the surface of the resultant cured product of the
bonding material, and it was then covered with a mold release film
(polyester). Next, slide glass was placed on the mold release film
to press it, and thereby the surface of the applied composite resin
was smoothed. Subsequently, the composite resin was irradiated with
light for 20 seconds using the aforementioned unit "JET LITE 3000"
through the mold release film. Thus, the composite resin was
cured.
[0211] One end face (circular section) of a stainless-steel
cylindrical rod (with a diameter of 7 mm and a length of 2.5 cm)
was bonded to the surface of the resultant cured product of the
dental filling composite resin using a commercially available
dental resin cement (manufactured by Kuraray Medical Inc.,
"PANAVIA21" (trade name)). After bonding, this sample was allowed
to stand still at room temperature for 30 minutes and was then
immersed in distilled water. Ten bonding test samples were produced
in total, and all the samples that had been immersed in distilled
water were allowed to stand still for 24 hours inside a thermostat
whose temperature was maintained at 37.degree. C. With respect to
five samples out of the ten samples, in order to evaluate the bond
strength in the early bonding stage, the bond strength was measured
immediately after they were allowed to stand still for 24 hours.
With respect to the other five samples, in order to evaluate bond
durability, bond strength was measured after 4000 thermal cycles
had been performed, with one cycle being a process for further
immersing each sample in 4.degree. C. cold water and 60.degree. C.
warm water alternately for one minute.
TABLE-US-00003 TABLE 3 Composition of Bonding Material Components
Amount added (parts by weight) HEMA 40 Bis-GMA 40 NPG 20
Photoinitiator (TMDPO) 3 Inorganic Filler 1 5.5 Inorganic Filler 2
1.5 NPG: neopentyl glycol dimethacrylate Inorganic filler 2:
"Ar380" manufactured by Japan Aerosil Inc.
(The Other Abbreviations have the Same Meanings as Described
Above.)
(3) Bonding Evaluation Test (Evaluations of Bond Strength and Bond
Durability)
[0212] The tensile bond strengths of the above-mentioned bonding
test samples were measured with a universal testing machine
(manufactured by Shimadzu Corporation), with the crosshead speed
being set at 2 mm/min, and the average value thereof was taken as
tensile bond strength.
Example 3
Application to Dental Self-Adhesive Composite Resin
(1) Preparation of Dental Self-Adhesive Composite Resin
[0213] The inorganic particles and polymerizable monomer
compositions indicated in Table 4 were mixed together,
respectively, and thereby paste-like dental composite resins were
prepared. The bond strength with respect to dentin is indicated
together.
TABLE-US-00004 TABLE 4 Self-Adhesive Composite Resin Compositions
and Bonding Evaluation Results Ex. Ex Ex Ex Ex C. Ex C. Ex C. Ex C.
Ex C. Ex C. Ex 3-1 3-2 3-3 3-4 3-4 3-1 3-2 3-3 3-4 3-5 3-6
Polymerizable EDMA 25 25 25 25 monomer (A) MDMA 25 25 XDMA 25 SDMA
25 Polymerizable GDMA 25 monomer for #801 25 comparison with (A)
Polymerizable HEMA 25 25 25 25 25 25 25 25 50 25 25 monomer (C)
having one polymerizable group and at least one hydroxyl group
Polymerizable MDP 10 10 10 10 10 10 10 10 10 10 10 monomer (D)
having acidic group Crosslinkable Bis-GMA 40 40 40 40 40 40 40 40
40 40 40 polymerizable monomer (E) Polymerization BAPO-1 1 1 1 1 1
initiator (B) BAPO-2 1 Polymerization TMDPO 1 1 initiator (G) CQ
0.5 1 1 0.5 1 0.5 Polymerization PDE 0.5 1 1 0.5 1 0.5 accelerator
(H) Filler (I) Inorganic Filler 3 230 230 230 230 230 230 230 230
230 230 230 Inorganic Filler 4 20 20 20 20 20 20 20 20 20 20 20
Bond strength with respect to 14.3 14.5 14.1 14.1 14.6 12.3 11.5
11.9 9.3 9.7 8.1 dentin (MPa) (No Adhesive) Bending Strength (MPa)
104 105 106 108 107 100 98 95 92 101 99 PDE: ethyl
p-(N,N-dimethylamino)benzoate Inorganic filler 3: Silane-treated
barium glass powder
[0214] Barium glass (manufactured by STEC, Product Code: "Raysorb
E-3000") was crushed with a ball mill and thus barium glass powder
was obtained. The mean particle size of the barium glass powder
thus obtained was measured with a laser diffraction particle size
distribution analyzer (manufactured by Shimadzu Corporation, Type
"SALD-2100") and it was 2.4 .mu.m. The surface treatment was
performed by a conventional method using 3 parts by weight of
3-methacryloyloxypropyltrimethoxysilane with respect to 100 parts
by weight of this barium glass powder. Thus, silane-treated barium
glass powder was obtained. Inorganic filler 4: Silane-treated
colloidal silica powder
[0215] 0.3 part by weight of acetic acid and 3 parts by weight of
3-methacryloyloxypropyltrimethoxysilane were added to 100 parts by
weight of distilled water, which was then stirred. Further 50 parts
by weight of colloidal silica powder (manufactured by Japan Aerosil
Inc., Product Code: "Aerosil OX50") was added thereto, which was
then stirred for one hour. After water was removed by
lyophilization, this was heat-treated at 80.degree. C. for five
hours and thus silane-treated colloidal silica powder was
obtained.
(The amounts of respective components added each are indicated in
the unit of parts by mass, and the other abbreviations have the
same meanings as described above.)
(2) Method of Evaluating Bonding to Bovine Teeth Dentin
[0216] A bovine incisor was wet-ground with #1000 silicon carbide
paper (manufactured by Nihon Kenshi Co., Ltd.) to be smooth and
thereby an enamel surface or dentin surface was exposed.
Thereafter, water on the surface was blown away using a dental air
syringe. An adhesive tape with a thickness of about 150 .mu.m
having a circular hole whose diameter was 3 mm was attached to the
exposed enamel surface or dentin surface. Each self-adhesive
composite resin composition produced above was placed in the
circular hole and this was covered with a mold release film
(manufactured by Kuraray Co., Ltd., "EVAL" (trade name)).
Thereafter, slide glass was placed on the mold release film to
press it, and this was irradiated with light for 20 seconds using
the dental light unit (manufactured by MORITA Corp., "JET LITE
3000" (trade name)). Thus, the composite resin was cured. Next, one
end face (circular section) of a stainless-steel cylindrical rod
with a diameter of 5 mm and a length of 1.5 cm was bonded to the
cured surface using a dental resin cement (manufactured by Kuraray
Medical Inc., "PANAVIA21" (trade name)). This was allowed to stand
still for 30 minutes and thus a test piece was obtained. Five
bonding test samples were produced in total.
(3) Bonding Evaluation Test
[0217] The tensile bond strengths of the above-mentioned bonding
test samples were measured with a universal testing machine
(manufactured by Shimadzu Corporation), with the crosshead speed
being set at 2 mm/min, and the average value thereof was taken as
tensile bond strength.
[0218] From the results of Examples 1 to 3, it was proved that the
dental materials, each of which was produced using a polymerizable
composition containing a polymerizable monomer (A) and
bisacylphosphine oxide (B) of the present invention, had excellent
initial bond strength and bond durability with respect to dentin.
It should be particularly noted that as can be judged from the
results of Example 1-1 where the polymerizable monomer (A) and
bisacylphosphine oxide (B) were used in combination, Comparative
Example 1-1 where only the polymerizable monomer (A) was used,
Comparative Examples 1-7 to 1-9 where only the bisacylphosphine
oxide (B) was used, and Comparative Example 1-10 where neither the
polymerizable monomer (A) nor the bisacylphosphine oxide (B) was
used, when the polymerizable monomer (A) and bisacylphosphine oxide
(B) were used in combination, higher effect of improving adhesive
properties was obtained as compared to the total of the effect of
improving adhesive properties obtained using only the polymerizable
monomer (A) and that obtained using only the bisacylphosphine oxide
(B).
INDUSTRIAL APPLICABILITY
[0219] The composition of the present invention contains a
polymerizable monomer (A) having a plurality of polymerizable
groups and a plurality of hydroxyl groups and bisacylphosphine
oxide (B) with excellent performance and therefore is useful for
applications that require curability and those that require
hydrophilicity. This composition can be used for various
applications including dental applications. Particularly, this
composition is suitable for dental materials such as a primer,
bonding material, cement, and composite resin.
* * * * *