JP3202333B2 - Photopolymerizable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photopolymerizable composition sensitive to visible light with high sensitivity.

[0002]

2. Description of the Related Art It has been widely known that an ethylenically unsaturated compound is activated by irradiation with energy rays in the presence of a photopolymerization initiator and easily polymerizes. For example, JP-A-2-196866 discloses that a photopolymerizable composition containing a compound having a radically polymerizable unsaturated double bond in the molecule and an acylphosphine oxide compound as a photopolymerization initiator is used as a conductive filler. Is disclosed that imparts conductivity by blending the compound. However, such conventional photopolymerizable compositions exhibit excellent curability when irradiated with ultraviolet light, but generally have low sensitivity to visible light and cannot achieve a practical polymerization rate. It was the current situation.

[0003]

In recent years, the above-mentioned photopolymerizable composition is polymerized by irradiating it with visible light from the viewpoints of safety, miniaturization of an irradiation device, and high-speed polymerization. Have been tried. That is, a photopolymerizable composition that can be polymerized by irradiation with visible light has many advantages as listed below, and therefore, its commercialization is strongly desired at present. (1) Use of a dangerous ultraviolet light irradiation device can be avoided.

[0004] Since a large amount of ultraviolet light and ozone generated from an ultraviolet light irradiation device is harmful to the human body, it is necessary to take measures to completely block ultraviolet light and ozone. Workers must be protected by protective glasses, protective gloves, etc.
Therefore, the ultraviolet light irradiating device cannot be easily installed anywhere, and it is necessary to provide a light-shielding device, an exhaust device, and the like with sufficient measures for installation.

On the other hand, when a photopolymerizable composition having a high sensitivity to visible light and a high polymerization rate is used, a visible light irradiating device whose light amount is equivalent to that of a normal room light may be used. No light or ozone is generated and there is no danger,
There is an advantage that it can be installed anywhere, regardless of the installation location. (2) The irradiation device can be reduced in size, and can be built into a small device.

As described above, in the visible light irradiating apparatus, for example, only a single small fluorescent lamp for indoor lighting needs to be used as a light source, and there is no need for ancillary equipment. Advantageously, it allows for incorporation into various small devices. Therefore, the present invention can be applied to various uses in which the conventional ultraviolet light irradiation device cannot be incorporated, and the added value of the small device can be increased. (3) Polymerization by a visible laser beam is possible.

[0007] Polymerization using a visible laser beam having a large output is possible, which is an effective means for forming a precise image. In addition to the method of irradiating the entire surface with a visible laser beam through a mask, it is also possible to irradiate while scanning a visible laser beam, and a planar or three-dimensional image can be formed by these methods. (4) High speed polymerization and deep polymerization are possible.

Since ultraviolet light is easily absorbed, when molding into a thick shape, the deep portion did not polymerize. Even when polymerization was possible, long irradiation was required. In contrast,
Since the visible light reaches a deep part, a molded product can be easily obtained in a short time even in a thick shape. (5) Polymerization can be performed in a transparent mold.

[0009] Since ultraviolet light is easily absorbed by a transparent mold, it is difficult to carry out polymerization in the transparent mold. On the other hand, according to visible light, polymerization in a transparent mold becomes possible,
In addition to the fact that the polymerization in the deep part is easy as described above, a molded article having a complicated shape can be obtained. (6) It can be applied to a photopolymerizable composition containing a pigment and a dye.

When pigments and dyes are blended, the pigments and dyes absorb ultraviolet light, which makes it difficult to polymerize with ultraviolet light. However, visible light has a long wavelength and is easily transmitted to the inside.
Even in this case, polymerization is easy. (7) The polymerization can be performed by directly irradiating the human body with light.

Since ultraviolet light is harmful to the human body, it should be avoided to irradiate the human body directly. However, the use of visible light can avoid this danger. Therefore, it is suitable for use in performing polymerization on a human body by directly or indirectly irradiating light to the human body for treatment or other purposes.

As described above, a photopolymerizable composition that can use visible light as a light source is useful in many respects and is expected to be developed for various uses. However, many conventional photopolymerizable compositions cannot be polymerized by irradiation with visible light, and even when polymerizable, they have problems such as extremely low sensitivity and low polymerization rate.

An object of the present invention is to solve the above problems and to provide a photopolymerizable composition having excellent sensitivity to visible light and having a sufficient polymerization rate even when visible light is used as a light source.

[0014]

SUMMARY OF THE INVENTION The present invention provides:
(A) an ethylenically unsaturated compound (b) a photopolymerization initiator comprising at least one of an acylphosphine oxide compound and a compound represented by the following general formula (1), and (c)
A photopolymerizable composition containing an organic phosphine compound as an essential component, wherein the photopolymerization initiator and the organic phosphine compound are combined.

[0015]

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The ethylenically unsaturated compound that can be used in the present invention is not particularly limited as long as it is a compound in which an ethylenically unsaturated double bond undergoes radical polymerization upon irradiation with energy rays. Compounds, unsaturated urethane compounds, styrene compounds, butadiene compounds, and the like. In the present invention, among such ethylenically unsaturated compounds, acrylate-based compounds are particularly preferred. This acrylate-based compound may be any of monofunctional, polyfunctional, monomeric, oligomer (prepolymer), and acryloyl groups. It may have a functional group other than (methacryloyl group). Specifically, monomers such as substituted or unsubstituted aliphatic acrylates, alicyclic acrylates, aromatic acrylates and ethylene oxide-modified acrylates thereof, epoxy acrylates, urethane acrylates, polyester acrylates, polyether acrylates, polyol acrylates, alkyds Oligomers such as acrylate, melamine acrylate, silicone acrylate, and polybutadiene acrylate, and methacrylate equivalents thereof can be given.

In the photopolymerizable composition of the present invention, the higher the number of ethylenically unsaturated double bonds in the above ethylenically unsaturated compound, the higher the polymerization rate when irradiated with visible light. The polymerization rate also depends on the type and molecular skeleton of the functional group in the ethylenically unsaturated compound. For example, when an acryloyl group is used, polymerization is performed at a higher polymerization rate than when a methacryloyl group is used. Therefore, in the photopolymerizable composition of the present invention, the polymerization rate during polymerization can be freely adjusted by appropriately selecting the ethylenically unsaturated compound to be blended.

In the photopolymerizable composition of the present invention, an acylphosphine oxide compound and at least one of the compounds represented by the above formula (1), preferably an acylphosphine oxide compound, are blended as a photopolymerization initiator.
These photopolymerization initiators generate radicals upon irradiation with visible light to induce radical polymerization of the ethylenically unsaturated compound.

The above-mentioned acylphosphine oxide compound which can be used in the present invention is represented by the following general formula (2).
No. -15471. As a specific example,
2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, 2,6 -Dimethylbenzoyldiphenylphosphine oxide, 4-methylbenzoyldiphenylphosphine oxide, 4-ethylbenzoyldiphenylphosphine oxide, 4-isopropylbenzoyldiphenylphosphine oxide, 1-methylcyclohexanoylbenzoyldiphenylphosphine oxide, 2,
Methyl 4,6-trimethylbenzoylphenylphosphinate, isopropyl 2,4,6-trimethylbenzoylphenylphosphinate and the like. On the other hand, examples of the compound represented by the above general formula (1) include 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and the like. These photopolymerization initiators can be used alone or in combination of two or more.

[0020]

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In the present invention, the photopolymerization initiator is used in an amount of 0.01 to 10% by weight based on the ethylenically unsaturated compound.
More preferably, it is in the range of 0.5 to 5% by weight.
If the amount of the photopolymerization initiator is less than this range, a sufficient polymerization rate cannot be obtained, and if the amount of the photopolymerization initiator is large, the degree of polymerization of the ethylenically unsaturated compound becomes insufficient,
Moreover, the photopolymerization initiator may remain after the polymerization, and the properties of the cured product may be deteriorated.

Further, in the present invention, other photopolymerization initiators are used in addition to the photopolymerization initiator comprising at least one of the above-mentioned acylphosphine oxide compound and the compound represented by the general formula (1). You can also. Such photopolymerization initiators that can be used in combination are not particularly limited, and specifically, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2 -Hydroxy-2-methylpropane-1-
On, 4- (2-hydroxyethoxy) phenyl- (2
-Hydroxy-2-propyl) ketone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, trichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-methyl [4- (methylthio) phenyl]- 2-morpholino-1
-Propanone, benzophenone, benzyl, methyl benzoyl formate, o-benzoyl methyl benzoate, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether,
Examples include benzoin isobutyl ether, xanthone, thioxaton, 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, 2-ethylanthraquinone, tetramethyltyrium monosulfide and the like. Of these, 2-hydroxy-2-
Methyl-1-phenylpropan-1-one, 1- (4-
(Isopropylphenyl) -2-hydroxy-2-methylpropan-1-one is a preferred component as a photopolymerization initiator used in combination in the photopolymerizable composition of the present invention. In the present invention, when a photopolymerization initiator as described above is used in combination, the polymerization rate of the photopolymerizable composition decreases, and thus these photopolymerization initiators significantly impair the polymerization rate of the photopolymerizable composition. It can be appropriately compounded within a range not known.

In the present invention, the organic phosphine compound blended with the above photopolymerization initiator is represented by the following general formula (3):
A first phosphine, a second phosphine or a third phosphine represented by
Phosphine. Specifically, as the first phosphine, phenylphosphine, octylphosphine, hexadecylphosphine, or the like is used. As the second phosphine, diphenylphosphine, dioctylphosphine, di (2-chlorophenyl) phosphine, di (methoxyphenyl) phosphine, Di (pentachlorophenyl) phosphine, butylphenylphosphine, bis (phenylphosphino)
Ethane and the like as the third phosphine, triphenylphosphine, tri (p-methoxyphenyl) phosphine,
Tri (p-tolyl) phosphine, tri (m-tolyl) phosphine, trinaphthylphosphine, tri (p-chlorophenyl) phosphine, tributylphosphine, tricyclohexylphosphine, methyldiphenylphosphine, dibutylphenylphosphine, 1,2-bis (diphenyl (Phosphino) ethane, bis (diphenylphosphino) methane and the like.

In the present invention, it is more preferable to mix the second phosphine or the third phosphine.
Particularly preferred is the incorporation of a third phosphine. The reason for this is that the third phosphine itself is the most stable among the organic phosphine compounds, and when it is incorporated into the photopolymerizable composition, it becomes possible to carry out polymerization at a higher polymerization rate.

[0025]

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In the photopolymerizable composition of the present invention, the sensitivity to visible light is increased by the addition of the organic phosphine compound as described above, and the polymerization rate upon irradiation with visible light is significantly increased. Although the reason is not clear, the electronic interaction between the organic phosphine compound and the photopolymerization initiator shifts the light absorption region of the photopolymerization initiator to a longer wavelength side and increases the absorbance of visible light. It is supposed to be. Therefore, even when the irradiation amount of visible light is small, the photopolymerization initiator is decomposed to generate a sufficient amount of radicals, and as a result, the photopolymerization has high sensitivity to visible light and a sufficient polymerization rate. Composition can be obtained.

In other words, the photopolymerizable composition of the present invention has the above-mentioned excellent characteristics only because the organic phosphine compound and the photopolymerization initiator are used in combination. Even if used alone, no such properties can be obtained.

In the present invention, the amount of the organic phosphine compound is preferably 0.01 to 10% by weight, more preferably 0.5 to 5% by weight, based on the ethylenically unsaturated compound. If the compounding amount of the organic phosphine compound is out of this range, a sufficient polymerization rate cannot be obtained, and if the compounding amount of the organic phosphine compound is large, the organic phosphine compound remains after polymerization and the properties of the cured product deteriorate. There is a risk.

The photopolymerizable composition of the present invention may optionally contain additives in addition to the essential components described above. For example, an organic or inorganic filler may be blended from the viewpoint of reducing the curing shrinkage, reducing the thermal expansion coefficient, improving the dimensional stability, improving the elastic modulus, adjusting the viscosity, improving the thermal conductivity, improving the strength, improving the toughness, and the like. As such a filler, a polymer, a ceramic, a metal, or the like can be used, and the shape is not particularly limited, such as a particle shape and a fibrous shape. When blending the polymer, not as a filler, but as a polymer
It can be dissolved, semi-dissolved or microdispersed in the photopolymerizable composition as a blend or a polymer alloy. Further, a colorant such as an organic or inorganic pigment or dye may be added as an additive to the photopolymerizable composition of the present invention, and the composition may be used for paints, inks and the like. Further, in the photopolymerizable composition of the present invention, as other additives, a softener, a plasticizer, a flame retardant, a stabilizer, an antioxidant, an ultraviolet absorber, a thixotropic agent, a coupling agent, and a dispersion stabilizer. Agent, fluidity imparting agent and the like can be appropriately compounded,
It is also possible to prepare by dissolving the essential components as described above and these additives blended as required in a suitable solvent.

As described above, in the photopolymerizable composition of the present invention, desired properties can be appropriately imparted by blending the above additives, and polymerization can be performed by irradiation with visible light. It has many advantages as described above. Therefore, the photopolymerizable composition of the present invention can be applied to a wide range of applications such as molding materials, coating agents, paints, adhesives, human body-related materials, and image forming materials.

Further, the photopolymerizable composition of the present invention has a sensitivity to ultraviolet light as high as or higher than that of visible light, and has a sufficient polymerization rate. Therefore, if necessary, the photopolymerizable composition of the present invention can be polymerized by irradiating ultraviolet light. For example, in the case where a polymer product is manufactured using a visible light irradiation device and an ultraviolet light irradiation device in combination, photopolymerization is performed when visible light is used as a light source, but is not polymerized when using ultraviolet light as a light source. In the case of a composition, it is necessary to separately prepare a photopolymerizable composition having high sensitivity to ultraviolet light and use a different photopolymerizable composition for each apparatus, which complicates the process. In contrast, the photopolymerizable composition of the present invention has excellent sensitivity to both visible light and ultraviolet light, so that it is not necessary to use a different photopolymerizable composition for each device, and practically Extremely effective.

[0032]

Examples of the present invention will be described below. Example 1

100 parts by weight of bisphenol A ethylene oxide-modified (n = 2) diacrylate KAYARAD R-551 (manufactured by Nippon Kayaku) as an ethylenically unsaturated compound and 2,4,6-trimethylbenzoyldiphenyl as a photopolymerization initiator 2 parts by weight of phosphine oxide and 3 parts of triphenylphosphine as an organic phosphine compound.
The photopolymerizable composition of the present invention was prepared by blending under parts by weight of yellow light. When 10 ml of the photopolymerizable composition was placed in a transparent glass sample bottle and irradiated with light from a commercially available fluorescent lamp for indoor lighting, it was instantaneously polymerized to obtain a cured product. Example 2

As photopolymerization initiators, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2-
Hydroxy-2-methyl-1-phenylpropane-1-
A photopolymerizable composition of the present invention was prepared in exactly the same manner as in Example 1 except that 3 parts by weight of a 50% by weight mixture of ON was mixed. When 10 ml of the photopolymerizable composition was placed in a transparent glass sample bottle and irradiated with light from a commercially available fluorescent lamp for indoor lighting, it was instantaneously polymerized to obtain a cured product. Example 3

A photopolymerizable composition of the present invention was prepared in exactly the same manner as in Example 2 except that 100 parts by weight of trimethylolpropane triacrylate was added as an ethylenically unsaturated compound. 10 ml of this photopolymerizable composition was placed in a transparent glass sample bottle, and irradiated with incandescent light,
Polymerization was instantaneously performed to obtain a cured product. Example 4

Except that 2 parts by weight of 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 was added as a photopolymerization initiator, the light-emitting method of the present invention was carried out in the same manner as in Example 1. A polymerizable composition was prepared. Put 10 ml of this photopolymerizable composition in a transparent glass sample bottle,
When irradiated with light from a commercially available fluorescent lamp for indoor lighting, a cured product was obtained by rapid polymerization. The polymerization rate at this time was about 1/2 of that of Example 1. Example 5

50% by weight of 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 and 2-hydroxy-2-methyl-1-phenylpropan-1-one as photopolymerization initiators A photopolymerizable composition of the present invention was prepared in exactly the same manner as in Example 1 except that 4 parts by weight of the mixture was blended. 10 ml of this photopolymerizable composition was placed in a transparent glass sample bottle, and irradiated with light from a commercially available fluorescent lamp for indoor lighting. As a result, a cured product was obtained by rapid polymerization. The polymerization rate at this time was about 1/2 of that of Example 1. Example 6

100 parts by weight of urethane acrylate M-1210 (manufactured by Toa Gosei Chemical Co., Ltd.) as an ethylenically unsaturated compound, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-2-methyl as photopolymerization initiators 50 of -1-phenylpropan-1-one
3 parts by weight of a mixture by weight, 3 parts by weight of triphenylphosphine as an organic phosphine compound, and 20 parts by weight of titanium oxide as a colorant under yellow light to prepare a photopolymerizable composition of the present invention. . When 1 ml of the photopolymerizable composition was placed in a transparent glass sample bottle and irradiated with light from an incandescent lamp, it was instantaneously polymerized to obtain a cured product. Example 7

100 parts by weight of ethylene glycol dimethacrylate as an ethylenically unsaturated compound and 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-2-methyl-1 as photopolymerization initiators
3 parts by weight of a 50% by weight mixture of -phenylpropan-1-one, 3 parts by weight of triphenylphosphine as an organic phosphine compound, and spherical fine particles of silicone resin having a uniform particle diameter (average particle diameter 0.8 μm) as a filler. The photopolymerizable composition of the present invention was prepared by blending under 120 parts by weight of yellow light and sufficiently dispersing the filler. After defoaming the photopolymerizable composition under reduced pressure, 1 ml was placed in a transparent glass sample bottle and irradiated with light from an incandescent lamp. As a result, a cured product was obtained by instantaneous polymerization. Comparative Example 1

The same composition as in Example 1 except that 2,4,6-trimethylbenzoyldiphenylphosphine oxide was not blended was irradiated with light from a fluorescent lamp for indoor lighting in the same manner as in Example 1. It could not be polymerized and remained liquid after 24 hours. Comparative Example 2

A composition exactly the same as that of Example 1 except that triphenylphosphine was not added was used.
When irradiated with light from a fluorescent lamp for indoor lighting in the same manner as in the above, polymerization could not be carried out and the liquid remained liquid after 24 hours. Comparative Example 3

The same composition as in Example 1 except that thioxanthone was used instead of 2,4,6-trimethylbenzoyldiphenylphosphine oxide as a photopolymerization initiator. When irradiated with light from a lamp, polymerization was not possible, and the liquid remained liquid after 24 hours. Comparative Example 4

A composition exactly the same as that of Example 1 except that triphenyl phosphate was added instead of triphenylphosphine was irradiated with light from a fluorescent lamp for interior lighting in the same manner as in Example 1 and polymerized. And remained liquid 24 hours later. Comparative Example 5

A composition exactly the same as that of Example 6 except that triphenylphosphine was not added was used.
When irradiated with light from an incandescent lamp in the same manner as in the above, polymerization was not possible and the liquid remained liquid after 24 hours.

[0045]

As described in detail above, the photopolymerizable composition of the present invention has excellent sensitivity to visible light and has a sufficient polymerization rate when irradiated with both ultraviolet light and visible light. . Therefore, visible light can be used as a light source and can be applied to various uses, and its industrial value is great.

Claims (1)

(57) [Claims] (1) an ethylenically unsaturated compound (b) an acylphosphine oxide compound and a compound represented by the following general formula (1):
A photopolymerizable composition comprising: a photopolymerization initiator comprising at least one compound represented by the formula: and (c) an organic phosphine compound as essential components. Embedded image