JP4292061B2 - Stereolithography method and apparatus - Google Patents

Description

  The present invention relates to an optical modeling method and an apparatus therefor for performing modeling by photocuring a photocurable resin composition with ultraviolet rays. More specifically, the present invention provides a high-quality optically shaped object that is excellent in appearance and dimensional accuracy while suppressing the deterioration of the liquid crystal drawing mask used as a drawing mask due to ultraviolet rays and extending the life of the liquid crystal drawing mask. The present invention relates to an optical modeling method and apparatus for manufacturing with high modeling accuracy and high modeling speed with high productivity.

  In recent years, an optical modeling method and apparatus for manufacturing a three-dimensional model by curing a photocurable resin based on data input to a three-dimensional CAD has been put into practical use. This stereolithography technology includes a model for verifying the appearance design in the middle of design, a model for checking the functionality of parts, a resin mold for manufacturing a mold, a base model for manufacturing a mold, etc. It attracts attention because it can easily form such complex three-dimensional objects.

  In manufacturing a modeled object by the optical modeling method, a method using a modeling bath is widely used, and as a procedure, a liquid photocurable resin is put in the modeling bath so that a desired pattern can be obtained on the liquid surface. A spot-shaped ultraviolet laser beam controlled by a computer is selectively irradiated to be photocured to a predetermined thickness to form a cured resin layer, and the cured resin layer is moved downward in the modeling bath to form a modeling bath. The photocurable resin liquid is flowed onto the cured resin layer to form a layer of the photocurable resin liquid, and the cured resin layer is formed by irradiating the photocurable resin liquid layer with a spot-like ultraviolet laser beam. A method of forming and repeating the above steps until a three-dimensional object having a predetermined shape and size is obtained is widely adopted.

  However, in the case of the above-described conventional method using spot-shaped ultraviolet laser light, a so-called planar photocured pattern is formed by moving one spot-shaped laser light while irradiating the surface of the photocurable resin. Since it is a stippling method, it takes a long time for modeling, and there is a problem that productivity is low. Moreover, since the ultraviolet laser device used as the light source is extremely expensive, this type of optical three-dimensional modeling apparatus is made expensive.

  In order to eliminate the above-described problems of the prior art using spot laser light, a light source that is less expensive than a spot laser light irradiation device, such as a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a mercury lamp, a metal halide lamp, or a xenon lamp Using a light source such as a high-intensity discharge lamp (High Intensity Dis-charge Lamp) (HID lamp), a drawing mask is placed downstream of the light source, and the cross-sectional shape pattern to be formed is drawn through the drawing mask. A three-dimensional model is formed by repeating the process of irradiating a modeling surface made of the photocurable resin composition with a corresponding light to form a cured resin layer having a predetermined cross-sectional shape pattern corresponding to the mask image of the drawing mask. Has been developed. At that time, as a drawing mask, there is known a method of performing optical modeling using a liquid crystal drawing mask in which a plurality of minute liquid crystal shutters capable of shielding and transmitting light in a minute dot area are arranged in a line or a plane. (For example, see Patent Documents 1 to 4).

  In optical three-dimensional modeling, light is transmitted through a liquid crystal drawing mask using the above-described conventional technique for manufacturing a three-dimensional model by spotting using spot laser light and a relatively inexpensive light source such as a high-intensity discharge lamp. In any of the above-described conventional modeling techniques for forming a photocured resin layer by irradiating light onto a modeling surface made of a curable resin composition, an ultraviolet curable resin composition is used as the photocurable resin composition. In general, a resin layer photocured by ultraviolet laser light or ultraviolet light contained in light from a light source is widely used. The reasons for this are as follows: (1) UV light has a short wavelength and does not penetrate deeply into the modeling surface, making it easy to adjust the depth of penetration of the light beam into the modeling surface. (2) On the other hand, visible light and infrared rays have long wavelengths and penetrate deep into the modeling surface, so it is difficult to adjust the penetration depth of the light into the modeling surface. It is difficult to form a photocured resin layer having a predetermined thickness and a uniform thickness, and accordingly, it is difficult to produce a three-dimensional modeled article having excellent dimensional accuracy; (3) cured with ultraviolet rays In addition, when an ultraviolet curable resin composition that is not cured by visible light or infrared light is used, an optical modeling operation can be performed even in a bright place, whereas when a photocurable resin composition that is cured by visible light is used, light irradiation is performed. The part which is not done It is hardened by visible light inside and cannot be photocured to a predetermined shape pattern, and it is necessary to perform modeling work in a dark room, which is extremely inferior in handling property of the photocurable resin composition and workability at the time of modeling. (4) When a photocurable resin composition that is cured by infrared rays is used, it is difficult to form a photocured shape pattern having a predetermined sharp outline, and it is difficult to obtain a molded article having excellent dimensional accuracy. It is done.

  Among the above-described modeling techniques for forming a resin layer photocured by ultraviolet rays using an ultraviolet curable resin composition as a photocurable resin composition, photocuring was performed by irradiating the modeling surface with light through a liquid crystal drawing mask. As described above, the technology for forming the resin layer has an area that can be cured at a time, compared to the technology that forms the resin layer that is photocured by irradiating the modeling surface with spot-like ultraviolet laser light and irradiating it with a stippling method. Since it is large, it is excellent in that the modeling speed is high and an inexpensive light source can be used as compared with a laser emitting device. However, when the present inventor repeated research on the optical modeling technology for forming a resin layer photocured by ultraviolet rays using a liquid crystal drawing mask, the liquid crystal drawing mask deteriorates early due to ultraviolet rays contained in the light from the light source, In order to make the optical modeling technology using a liquid crystal drawing mask practically effective, the mask function (that is, the light shielding and translucency function in a minute dot area) is easily lost in a short period of time. It has been found that it is necessary to prevent the early deterioration of the liquid crystal drawing mask due to ultraviolet rays and to extend its life.

  The liquid crystal itself has been widely used in recent years as a liquid crystal display in personal computers, mobile phones, large televisions, and the like, and is also used in the field of liquid crystal projectors. In these applications, a light source that emits light including ultraviolet rays, such as a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, or a xenon lamp, is usually used for display by liquid crystal. Therefore, in these fields, the prevention of deterioration of the liquid crystal due to ultraviolet rays has been studied, but in these fields, the light rays used for the liquid crystal display are mainly visible rays, and ultraviolet rays are hardly used. Attempts have been made exclusively to extend the life of liquid crystals by cutting all ultraviolet rays and short-wavelength visible rays close to ultraviolet rays. As such a conventional technique, for example, for use in a liquid crystal projector or the like that cuts light having a wavelength of 430 nm or less (cuts all ultraviolet rays having a wavelength of 400 nm or less and visible light having a short wavelength of 400 to 430 nm). UV absorbing filter glass is known (see Patent Document 5).

  However, in the optical modeling technique using a liquid crystal drawing mask, as described above, from the viewpoints of the handleability and workability of the photocurable resin composition at the time of optical modeling, and the dimensional accuracy of the resulting optical modeling object, photocuring It is necessary to form a photocured resin layer having a predetermined shape pattern on the modeling surface by ultraviolet rays contained in the light from the light source, using the ultraviolet curable resin composition as the curable resin composition, and thus the light from the light source If all the ultraviolet rays contained in are cut, stereolithography itself cannot be performed. Therefore, the conventional technology (described in Patent Document 5 described above) for liquid crystal displays and liquid crystal projectors such as personal computers, mobile phones, large televisions, etc. However, it is necessary to develop a technology for improving durability against ultraviolet rays, which is peculiar to the optical modeling technology using a liquid crystal drawing mask. That is, using a liquid crystal drawing mask, an optical modeling technique for manufacturing a three-dimensional three-dimensional object using ultraviolet rays and an optical modeling technique for manufacturing a two-dimensional object (modeling pattern) (for example, using a liquid crystal drawing mask) Common to both resist technology).

  In addition, liquid crystal drawing masks tend to be deteriorated even by infrared rays having a large heating effect, although not as much as ultraviolet rays. From this point, in the optical modeling technique using a liquid crystal drawing mask, the deterioration of the liquid crystal drawing mask due to ultraviolet rays is suppressed. There is a need for the development of a technology that can prevent or suppress deterioration due to infrared rays and further extend the life of the liquid crystal drawing mask.

Japanese Patent Laid-Open No. 62-288844 Japanese Patent Laid-Open No. 3-227222 JP 7-2905789 A JP-A-8-112863 JP 2003-48749 A

An object of the present invention is to provide a UV modeling resin that uses an ultraviolet curable resin composition and uses a liquid crystal drawing mask to form a resin layer photocured by ultraviolet rays contained in light from a light source. While suppressing deterioration due to UV or infrared and infrared, and extending the durability life of the liquid crystal drawing mask, while preventing the occurrence of curing unevenness and unevenness of strength with high modeling accuracy, An object of the present invention is to provide an optical modeling method and apparatus that can be manufactured at a high modeling speed with high productivity and low cost.
In particular, the object of the present invention is to use an inexpensive light source such as a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a mercury lamp, a metal halide lamp, a xenon lamp, etc. without using an expensive ultraviolet laser device, Or, by suppressing the deterioration of the liquid crystal drawing mask due to ultraviolet rays and infrared rays, and realizing a long life of the liquid crystal drawing mask, a high-quality modeling object with high modeling accuracy and no curing unevenness and strength unevenness can be formed at high speed. It is to provide a practical technology that can be manufactured economically.

In order to achieve the above object, the present inventor has intensively studied. As a result, light modeling is performed through a process of irradiating a modeling surface made of an ultraviolet curable resin composition through a liquid crystal drawing mask and forming a photocured resin layer having a predetermined shape pattern by ultraviolet rays contained in the light. In manufacturing a product, not all of the ultraviolet rays contained in the light from the light source are used as they are for the photo-cured resin layer formation, but only using ultraviolet rays having a predetermined wavelength within a wavelength range of 300 to 390 nm. A photocuring step that forms a cured resin layer and at the same time prevents or suppresses exposure of the liquid crystal drawing mask by ultraviolet rays having a wavelength different from the ultraviolet rays having the predetermined wavelength, particularly ultraviolet rays having a wavelength shorter than the ultraviolet rays having the predetermined wavelength. It is found that the optical lithography can be performed while suppressing (reducing) the deterioration of the liquid crystal drawing mask due to ultraviolet rays and extending the life of the liquid crystal drawing mask. It was.
In addition, when the inventor prevents or suppresses exposure of the liquid crystal drawing mask by ultraviolet rays having a wavelength different from the ultraviolet rays having the predetermined wavelength, and simultaneously prevents or suppresses exposure by infrared rays, the liquid crystal drawing mask is deteriorated. It has been found that the usable life can be further extended by further suppressing and reducing the service life.

  Then, the inventor of the present invention provides a means for preventing or suppressing exposure of the liquid crystal drawing mask by ultraviolet light having a wavelength different from the predetermined wavelength used for forming the photocured resin layer. If a shielding means such as a filter that allows a predetermined amount or more of ultraviolet rays different from the predetermined wavelength to be absorbed and / or reflected is disposed on the upstream side of the liquid crystal drawing mask, the predetermined wavelength is different. It is possible to smoothly form a photocured resin layer having a desired shape pattern with ultraviolet rays of a predetermined wavelength while easily suppressing exposure of the liquid crystal drawing mask by ultraviolet rays, and an ultra-high pressure mercury lamp or a high-pressure mercury lamp is used as a light source. By ultraviolet rays (commonly called “i-line”) having a wavelength of 365 nm included in the light emitted from the ultra-high pressure mercury lamp or the high-pressure mercury lamp. In addition to forming a photocured resin layer and shielding a predetermined amount or more of ultraviolet rays having a wavelength of 340 nm or less with a shielding filter or the like disposed upstream of the liquid crystal drawing mask, the ultraviolet ray liquid crystal drawing mask is maintained while maintaining a high photocuring speed. It has been found that the optical modeling technology that can suppress deterioration more effectively and is excellent in terms of practicality and the like can be provided, and the present invention has been completed based on these various findings.

That is, the present invention
(1) Controlled through a liquid crystal drawing mask in which a plurality of minute liquid crystal shutters capable of light shielding and translucency in a minute dot area are arranged in a linear or planar manner on a modeling surface made of a photocurable resin composition After irradiating light to form a photocured resin layer having a predetermined shape pattern, a photocurable resin composition for one layer is applied on the photocured resin layer to form a modeling surface, A target three-dimensional model is a step of further forming a photocured resin layer having a predetermined shape pattern by irradiating light under control through a liquid crystal drawing mask on a modeling surface made of a photocurable resin composition. It is an optical modeling method that is repeated until it is formed, using an ultraviolet curable resin composition as a photocurable resin composition, and forming a photocured resin layer with a wavelength of ultraviolet rays contained in light from a light source In the range of 300-390 nm This is a stereolithography method characterized in that it is performed with ultraviolet rays having a predetermined wavelength and is performed while preventing or suppressing exposure of the liquid crystal drawing mask by ultraviolet rays having a wavelength different from that of the predetermined wavelength.

And this invention,
(2) Controlled through a liquid crystal drawing mask in which a plurality of minute liquid crystal shutters capable of light shielding and translucency in a minute dot area are arranged linearly or planarly on a modeling surface made of a photocurable resin composition An optical modeling method comprising a step of forming a photocured resin layer having a predetermined pattern by irradiating light, wherein the resin is photocured using an ultraviolet curable resin composition as the photocurable resin composition The layer is formed by ultraviolet rays having a predetermined wavelength within a wavelength range of 300 to 390 nm among ultraviolet rays contained in light from the light source, and exposure of the liquid crystal drawing mask by ultraviolet rays having a wavelength different from that of the predetermined wavelength. It is an optical modeling method characterized by being performed while preventing or suppressing.

Furthermore, the present invention provides
(3) At least 60% of ultraviolet rays having a predetermined wavelength within the wavelength range of 300 to 390 nm used for forming the photocured resin layer are allowed to pass upstream of the liquid crystal drawing mask, but within the wavelength range of 300 to 390 nm. Liquid crystal drawing using ultraviolet light having a wavelength different from that of the predetermined wavelength used for forming the photocured resin layer by arranging shielding means for shielding 50% or more of other ultraviolet light having a wavelength different from that of the predetermined wavelength. The stereolithography method according to (1) or (2) above, wherein the photocured resin layer is formed while preventing or suppressing exposure of the mask;
(4) The shielding means allows 60% or more of ultraviolet rays having a predetermined wavelength within a wavelength range of 300 to 390 nm used for forming a photocured resin layer to pass but the predetermined wavelength being within a wavelength range of 300 to 390 nm. The optical shaping method according to (3), which is a filter that absorbs and / or reflects 50% or more of ultraviolet light having a shorter wavelength than the ultraviolet light;
(5) While passing 60% or more of ultraviolet rays having a predetermined wavelength within the wavelength range of 300 to 390 nm used for forming the photocured resin layer on the upstream side of the liquid crystal drawing mask, 40% of light rays having a wavelength of 780 nm or more are passed. The stereolithography method according to any one of (1) to (4), wherein a shielding means for shielding the above is disposed to further prevent or suppress exposure of the liquid crystal drawing mask by light having a wavelength of 780 nm or more;
It is.

And this invention,
(6) Among the ultraviolet rays contained in the light from the light source, the ultraviolet curable resin composition is promptly used as the ultraviolet ray having the predetermined wavelength in the range of the wavelength of 300 to 390 nm for forming the photocured resin layer. The optical shaping method according to any one of the above (1) to (5), which has ultraviolet light intensity that can be cured to a high level and has a relatively small deterioration effect on the liquid crystal drawing mask.

Furthermore, the present invention provides
( 7 ) The optical shaping method according to any one of (1) to ( 6 ), wherein a high-intensity discharge lamp is used as a light source; and
( 8 ) An ultraviolet curable resin composition that is at least cured by ultraviolet light having a wavelength of 365 nm or the vicinity thereof but is not cured by visible light or infrared light having a wavelength of 400 nm or more is used as the light curable resin composition, Using a high-pressure mercury lamp, it passes 60% or more of ultraviolet light having a wavelength of 365 nm or its vicinity contained in light emitted from an ultra-high pressure mercury lamp or high-pressure mercury lamp and shields 50% or more of ultraviolet light having a wavelength of 340 nm or less. The shielding means is disposed on the upstream side of the liquid crystal drawing mask, and the photocured resin layer is formed with ultraviolet light having a wavelength of 365 nm or in the vicinity thereof while preventing or suppressing exposure of the liquid crystal drawing mask with ultraviolet light having a wavelength of 340 nm or less ( 1)-( 7 ) any stereolithography method;
It is.

And this invention,
( 9 ) Means for forming a modeling surface comprising a photocurable resin composition;
A light source that emits light including ultraviolet rays of a predetermined wavelength and ultraviolet rays of other wavelengths in the range of a wavelength of 300 to 390 nm for curing the photocurable resin composition;
A liquid crystal drawing mask in which a plurality of minute light shutters capable of shielding and transmitting light in a minute dot area are arranged in a line or a plane; and
While passing more than 60% of ultraviolet rays with a predetermined wavelength and the curing the photocurable resin composition, to absorb and / or reflect more than 50% of ultraviolet rays having a wavelength other than the predetermined wavelength, the upstream side of the liquid crystal image drawing mask Shielding means arranged on;
Is an optical modeling apparatus.

The present invention also provides:
( 10 ) The optical modeling apparatus according to ( 9 ), wherein the light source is a high-intensity discharge lamp;
( 11 ) While passing 60% or more of ultraviolet rays having a predetermined wavelength within the wavelength range of 300 to 390 nm for curing the photocurable resin composition to the upstream side of the liquid crystal drawing mask, 40% of light having a wavelength of 780 nm or more is passed. The optical modeling apparatus according to ( 9 ) or ( 10 ) above, further comprising shielding means for shielding the above; and
(12) light source is an ultra-high pressure mercury lamp or high pressure mercury lamp, but pass more than 60% of the ultraviolet radiation of a predetermined wavelength and the curing the photocurable resin composition 50% of the ultraviolet radiation of a wavelength other than the predetermined wavelength ( 9 ) The shielding means that absorbs and / or reflects the above is a filter that passes 60% or more of ultraviolet light having a wavelength of 365 nm or its vicinity and absorbs and / or reflects 50% or more of ultraviolet light having a wavelength of 340 nm or less. Any one of ( 11 ) stereolithography apparatus;
It is.

In the case of the present invention, while suppressing the deterioration of the liquid crystal drawing mask due to ultraviolet rays or the deterioration of ultraviolet rays and infrared rays and extending the durable life of the liquid crystal drawing mask, the target photocured shaped article or photocured shaped pattern, etc. Can be manufactured with high modeling accuracy, high curing speed, high productivity, and low cost while preventing the occurrence of curing unevenness and strength unevenness.
Furthermore, according to the present invention, an inexpensive light source such as a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a mercury lamp, a metal halide lamp, or a xenon lamp is used without using an expensive ultraviolet laser device as the light source. Using ultraviolet rays having a predetermined wavelength within a wavelength range of 300 to 390 nm among ultraviolet rays contained in light emitted from these light sources, while suppressing deterioration of the liquid crystal drawing mask due to ultraviolet rays or ultraviolet rays and infrared rays The above-described high-quality shaped objects, photocured shape patterns, and the like can be manufactured at a high modeling speed and economically.

The present invention is described in detail below.
In the present invention,
(1) Under control through a liquid crystal drawing mask in which a plurality of minute liquid crystal shutters capable of shielding and transmitting light in a minute dot area are linearly or planarly arranged on a modeling surface made of an ultraviolet curable resin composition After forming a photocured resin layer having a predetermined shape pattern by irradiating light, an ultraviolet curable resin composition for one layer is applied on the photocured resin layer to form a modeling surface, A target three-dimensional model is a step of further forming a photocured resin layer having a predetermined shape pattern by irradiating light under control through a liquid crystal drawing mask on a modeling surface made of an ultraviolet curable resin composition. Repetitively producing a three-dimensional model until it is formed; or
(2) A product (for example, a resist or the like) having a photocured resin layer having a predetermined shape pattern by irradiating light on a modeling surface made of an ultraviolet curable resin composition under control through the liquid crystal drawing mask described above Products).

  The above-described modeling technique (1) related to the manufacture of a three-dimensional model is generally a modeling table surface by placing a modeling table in a modeling bath filled with a liquid ultraviolet curable resin composition and lowering the modeling table. 1 layer of a liquid ultraviolet curable resin composition layer is formed, and a photocured resin layer (hereinafter referred to as “photocured layer”) having a predetermined pattern and thickness by irradiating light under control through a liquid crystal drawing mask. The molding table is further lowered to form a liquid ultraviolet curable resin composition layer for one layer on the surface of the photocured layer, and light is controlled through a liquid crystal drawing mask. Can be carried out by adopting a modeling bath method in which a step of integrally laminating and forming a photocured layer having a predetermined pattern and thickness is repeated.

  In addition, the above-described modeling technique (1) related to the manufacture of a three-dimensional model is, for example, a modeling table is arranged in a gas atmosphere, and one layer of liquid, paste, powder, or thin film is formed on the modeling table surface. After applying a UV curable resin composition of the above and irradiating light under control through a liquid crystal drawing mask to form a photocured layer having a predetermined pattern and thickness, a liquid for one layer is formed on the photocured layer surface, A step of applying a paste-form, powder-form or thin-film-form ultraviolet curable resin composition and irradiating light under control through a liquid crystal drawing mask to integrally form a photocured layer having a predetermined pattern and thickness. It is also possible to adopt a method that is repeated. In the case of this method, the modeling table or the photocuring layer is faced upward, an ultraviolet curable resin composition is applied to the upper surface, and the photocuring layer is sequentially laminated by irradiating light through a liquid crystal drawing mask. The method may be adopted, or the modeling table or photo-curing layer is placed vertically or diagonally, an ultraviolet curable resin layer is applied on the modeling table surface or the photo-curing layer surface, and light is irradiated through a liquid crystal drawing mask. A method of sequentially laminating and forming photocuring layers may be employed, or an ultraviolet curable resin layer composition may be disposed on the modeling table surface or the photocuring layer surface with the modeling table or photocuring layer disposed downward. A method may be employed in which light is irradiated through a liquid crystal drawing mask and a photo-curing layer is sequentially stacked below. In applying the ultraviolet curable resin composition to the modeling table surface or the photocured layer surface, for example, an appropriate method such as blade coating, cast coating, roller coating, transfer coating, brush coating, spray coating, etc. can be adopted. .

In addition, the modeling technique of (2) described above is, for example, an ultraviolet curable resin composition on an appropriate base material (metal, plastic, fabric, paper, ceramic, glass, wood, composite of two or more thereof). Form a layer of objects, and irradiate light under control through a liquid crystal drawing mask in which a plurality of micro liquid crystal shutters that can shield and transmit light in a micro dot area are arranged in a line or plane, It can be used to form a photocured resin layer having a predetermined shape pattern. Therefore, the modeling technique (2) can be used for the production of, for example, a resist or other product having a photocured resin layer having a predetermined shape pattern on a substrate.
Among these, this invention can be used especially effectively for the manufacturing technique of the three-dimensional molded item of said (1).

The liquid crystal drawing mask used in the present invention is a linear liquid crystal drawing mask in which a plurality of minute liquid crystal shutters capable of shielding and transmitting light in a minute dot area are arranged in a linear shape (for example, the X direction or the Y direction), or a planar shape. Any of a square or rectangular planar liquid crystal drawing mask arranged in parallel in the (X-Y direction) may be used, and among these, it is preferable to use a planar liquid crystal drawing mask from the viewpoint of modeling speed (modeling efficiency). The number of micro liquid crystal shutters (image elements) arranged on the linear liquid crystal drawing mask or the planar liquid crystal drawing mask is not particularly limited, and conventionally known ones can be used. As a liquid crystal shutter (liquid crystal display element), for example, QVGA (number of pixels = 320 dots × 240 dots), VGA (number of pixels = 640 × 480 dots), SVGA (number of pixels = 800 × 600 dots), UXGA (number of pixels) = 1024 × 768 dots), QSXGA (number of pixels = 2560 × 2648 dots), and the like, and these liquid crystal shutters have been widely sold.
Although there is some difference in the degree of deterioration of the liquid crystal drawing mask due to ultraviolet rays due to differences in the type of liquid crystal that makes up the liquid crystal drawing mask, the material of other parts that make up the liquid crystal drawing mask, the structure of the liquid crystal drawing mask, etc. In the case of the present invention, any liquid crystal drawing mask can be prevented from deteriorating and the usable life can be extended.

  In carrying out the optical modeling of the present invention, a photocured resin layer of one layer is formed by irradiating the modeling surface made of the ultraviolet curable resin composition through the liquid crystal drawing mask with the liquid crystal drawing mask stationary. It may be formed, or the mask image of the liquid crystal drawing mask is intermittently changed during the formation of the photocured resin layer for one layer, and the photocured resin layer is formed by moving the liquid crystal drawing mask to the next position. Alternatively, the liquid crystal drawing mask may be synchronized with the change of the mask image of the liquid crystal drawing mask continuously like a television image or movie when forming a photo-cured resin layer for one layer. It may be moved continuously to form a photo-cured resin layer for one layer, or two or more of the above-described methods may be adopted for stereolithography.

  In the present invention, an ultraviolet laser emitting device (for example, an Ar laser emitting device, a He-Cd laser emitting device, an LD laser emitting device, etc.) can also be used as a light source, but an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, A high-intensity discharge lamp (HID lamp) such as a xenon lamp or a halogen lamp is preferably used. Among them, as will be described later, the ultra-high pressure mercury lamp and the high-pressure mercury lamp contain ultraviolet rays having a light intensity capable of forming a photocured resin layer in a short time, and are used for forming a photocured resin layer. It is preferably used from the viewpoint that it is easy to shield ultraviolet rays of other wavelengths, and an ultrahigh pressure mercury lamp is more preferably used.

The shape, size, and number of the light source are not particularly limited, and can be appropriately selected depending on the shape and size of the liquid crystal drawing mask, the shape and size of the shape pattern of the photocured resin layer to be formed, For example, the shape may be a dot, a sphere, a rod, or a plane, or a dot or a spherical light source may be arranged in a line or a plurality of lines directly on the back side of the liquid crystal drawing mask.
In addition, the light source may be provided so as to be movable together with the liquid crystal drawing mask on the back side of the liquid crystal drawing mask, or for the purpose of improving modeling accuracy, improving modeling speed, reducing the weight of the apparatus, improving maintainability, etc. Install the light source so that it does not move to a fixed position and guide the light from the light source to the back of the liquid crystal drawing mask through an optical fiber, light guide or other light transmission means, and remove the liquid crystal drawing mask from the optical fiber, light guide or other light transmission means Therefore, the modeling surface may be irradiated with light.
Moreover, you may employ | adopt the system which condenses and raises light energy using a some light source for the improvement of modeling speed. In particular, when an optical fiber or a light guide is used, there is an advantage that a plurality of light sources can be easily condensed.

In the present invention, the ultraviolet ray contained in the light from the light source is not used as it is for the formation of the photocured resin layer, but the ultraviolet ray contained in the light from the light source has a predetermined wavelength within the range of 300 to 390 nm. Ultraviolet rays (hereinafter sometimes referred to simply as “ultraviolet rays of a predetermined wavelength”) are used for forming a photocured resin layer, and at the same time, ultraviolet rays having a wavelength different from that of the predetermined wavelength (hereinafter referred to as “other than predetermined wavelengths”). UV light is sometimes shielded upstream of the liquid crystal drawing mask, that is, before ultraviolet light other than the predetermined wavelength reaches the liquid crystal drawing mask, the liquid crystal drawing mask is exposed to ultraviolet light other than the predetermined wavelength. The formation process of the photocured resin layer is performed while preventing or suppressing the above.
Between the light emitted from the light source, ultraviolet light having a predetermined wavelength used for forming the photocured resin layer is sandwiched, and ultraviolet light having a longer wavelength than the predetermined wavelength and ultraviolet light having a shorter wavelength than the predetermined wavelength are used. If it is included, it is more preferable to prevent or suppress the exposure of the liquid crystal drawing mask by both the ultraviolet light having the long wavelength and the ultraviolet light having the short wavelength from the viewpoint of suppressing deterioration of the liquid crystal drawing mask. Depending on the energy intensity of the long wavelength ultraviolet light and the short wavelength ultraviolet light, in order to prevent more efficient deterioration of the liquid crystal drawing mask due to ultraviolet light other than the predetermined wavelength, only one ultraviolet light with high energy intensity is used. You may make it shield.

In the present invention, 60% or more, preferably 70% or more, more preferably 80% or more of the ultraviolet ray having a predetermined wavelength used for forming the photocured resin layer is allowed to pass upstream of the liquid crystal drawing mask. Is provided with a shielding means such as a filter that shields 50% or more, preferably 60% or more, of other ultraviolet rays having different wavelengths by absorption and / or reflection, and is used for forming the photocured resin layer. It is preferable to prevent or suppress the exposure of the liquid crystal drawing mask by ultraviolet rays having a wavelength different from the ultraviolet rays.
As used herein, the percentage of ultraviolet light having a predetermined wavelength used for the formation of a photocured resin layer refers to the percentage of energy of ultraviolet light that passes through the total energy (total light intensity) of ultraviolet light having a predetermined wavelength. Further, the shielding percentage of ultraviolet light having a wavelength different from the predetermined wavelength refers to the percentage of energy shielded with respect to the total energy (total light intensity) of ultraviolet light having a wavelength different from the predetermined wavelength.

  Further, as a method for suppressing exposure of the liquid crystal drawing mask by ultraviolet light having a wavelength different from the ultraviolet light having a predetermined wavelength used for forming the photocured resin layer, in addition to the above-described shielding method using a filter, the upstream side of the liquid crystal drawing mask A prism or diffraction grating is arranged on the LCD to split the light from the light source for each wavelength, and the liquid crystal drawing mask emits ultraviolet light having a wavelength different from the predetermined wavelength used for forming the photocured resin layer. The UV curable resin composition is used to form a light-cured resin layer, or UV light having a predetermined wavelength or UV light having a predetermined wavelength and visible light are passed through a liquid crystal drawing mask. It is also possible to employ a method of proceeding in a direction in which a modeling surface made of an object is present.

  The shielding means such as a filter and the spectroscopic means such as a prism and a diffraction grating may be arranged near the light source or near the liquid crystal drawing mask as long as they are upstream of the liquid crystal drawing mask. However, they may be arranged at other positions.

  As the ultraviolet ray having a predetermined wavelength used for forming the photocured resin layer, the curing wavelength of the ultraviolet curable resin composition (particularly, the type of photopolymerization initiator and photosensitizer contained in the ultraviolet curable resin composition, light Absorption wavelengths of polymerization initiators and photosensitizers, among them, the optimum absorption wavelength), UV curing characteristics of resin components, monomer components, and other components that constitute UV curable resin compositions (especially the light wavelengths that cause photocuring) It is preferable to determine in consideration comprehensively according to each situation such as the type of light source, the type of ultraviolet light contained in the light source, the spectral distribution, and the intensity thereof. In particular, as the ultraviolet ray having the predetermined wavelength for forming the photocured resin layer, the light intensity (light energy) that can quickly cure the ultraviolet curable resin composition among the ultraviolet rays contained in the light from the light source. It is preferable to use ultraviolet rays having a relatively low deterioration effect on the liquid crystal drawing mask.

In general, as the wavelength of ultraviolet rays becomes shorter, the deterioration effect on the liquid crystal drawing mask increases, the number of usable photocurable resin compositions decreases, and the number of optical parts and materials that can be used inexpensively and favorably decreases. since, in the present invention, against the formation of the photocured resin layer, of UV, utilizing an ultraviolet having a predetermined wavelength within the wavelength range of 300～390Nm. UV of the predetermined wavelength to be utilized in the present invention for the formation of the photocured resin layer is preferably a UV with a predetermined wavelength in the range of 330～390Nm, UV with a predetermined wavelength in the range of 350~390nm It is more preferable that
Therefore, the light source includes ultraviolet rays having a light intensity capable of satisfactorily curing the ultraviolet curable resin composition in the wavelength range of 300 to 390 nm, of which 330 to 390 nm, particularly 350 to 390 nm, A light source having a spectral distribution that can easily separate ultraviolet rays in the above wavelength range and ultraviolet rays of less than 300 nm (among them, ultraviolet rays of less than 330 nm, particularly less than 350 nm) with a filter or other spectroscopic device is preferably used. Specific examples of such a light source include high-intensity discharge lamps (HID lamps) such as ultra-high pressure mercury lamps, high-pressure mercury lamps, low-pressure mercury lamps, metal halide lamps, xenon lamps, and halogen lamps. Among them, an ultrahigh pressure mercury lamp or a high pressure mercury lamp is preferably used.

In the present invention, an ultra-high pressure mercury lamp preferably used as a light source has a spectral distribution comprising a plurality of peaks clearly separated from each other as shown in FIG. 1, and the high-pressure mercury lamp is also as shown in FIG. It has a spectral distribution consisting of a plurality of peaks clearly separated from each other. As shown in FIGS. 1 and 2, the light emitted from the ultra-high pressure mercury lamp and the high-pressure mercury lamp independently has a high-intensity ultraviolet peak suitable for curing the photocurable resin composition at a wavelength of 365 nm and its vicinity. And there is no other ultraviolet peak between 365 nm and 400 nm, and most of the ultraviolet light other than 365 nm is distributed in the wavelength range of 0 to 340 nm.
Therefore, using an ultra-high pressure mercury lamp or a high-pressure mercury lamp as a light source, using an ultraviolet curable resin composition that is at least cured by ultraviolet light having a wavelength of 365 nm or in the vicinity thereof and not cured by visible light or infrared light having a wavelength of 400 nm or more, Among the light emitted from these mercury lamps, a shielding means such as a filter that transmits ultraviolet light having a wavelength of 365 nm or its vicinity and light having a wavelength longer than that and blocks ultraviolet light having a wavelength of 340 nm or less is provided upstream of the liquid crystal drawing mask. By arranging it on the side, it is possible to quickly and smoothly form the photocured resin layer by passing the ultraviolet light of 365 nm or the vicinity through the liquid crystal drawing mask, and at the same time, the wavelength is shorter than that and the liquid crystal drawing mask. Most of the ultraviolet rays that have a large deterioration effect on the liquid crystal reach the liquid crystal drawing mask. Shields (cuts) before, it is possible to more effectively suppress the deterioration of the liquid crystal image drawing mask with ultraviolet.

  When comparing ultra-high pressure mercury lamps with high-pressure mercury lamps, the ultra-high pressure mercury lamp has a shorter arc length than the high-pressure mercury lamp and the lamp itself is downsized. There is an advantage that installation is easy without taking up space, and there is an advantage that the radiant energy is large in addition to that, and therefore, an ultra-high pressure mercury lamp is more preferably used.

  In the present invention, together with the ultraviolet shielding means different from the ultraviolet rays having the predetermined wavelength, 60% or more, preferably 70% or more, of the ultraviolet rays having the predetermined wavelength used for forming the photocured resin layer on the upstream side of the liquid crystal drawing mask. More preferably, 80% or more is allowed to pass, but 40% or more, preferably 50% or more, more preferably 60% or more of light having a wavelength of 780 nm or more can be shielded by absorption and / or reflection or spectroscopy. It is desirable to further dispose a filter and other shielding means to further prevent or suppress the exposure of the liquid crystal drawing mask by light rays (infrared rays, heat rays) having a wavelength of 780 nm or more. In that case, the liquid crystal drawing mask is deteriorated by ultraviolet rays. The prevention of deterioration due to infrared rays and the prevention of deterioration by infrared rays can further extend the durable life of the liquid crystal drawing mask.

  In the present invention, for the purpose of improving modeling accuracy, improving modeling speed, reducing the weight of the apparatus, improving maintainability, reducing the cost of the apparatus, and the like, the type of light source disposed on the upstream side (back side) of the liquid crystal drawing mask, Depending on the shape, number, shape and size of the liquid crystal drawing mask, etc., a means for guiding the light from the light source to the liquid crystal drawing mask satisfactorily (for example, a condensing lens, a Fresnel lens, etc.) and the liquid crystal drawing mask Means (for example, a projection lens, a projector lens, etc.) for irradiating a mask image (light image that has passed through a liquid crystal drawing mask) to a predetermined position on a modeling surface made of an ultraviolet curable resin composition with high modeling accuracy may be disposed. preferable.

  In the present invention, an ultraviolet curable resin composition that is cured by ultraviolet rays and is not cured by visible light and infrared rays is preferably used as the photocurable resin composition. The ultraviolet curable resin composition may be in any form such as liquid, paste, powder, and thin film, and is particularly preferably in the form of liquid from the viewpoint of handleability during optical modeling.

  In the present invention, as an ultraviolet curable resin composition, various oligomers conventionally used in stereolithography that is cured by ultraviolet rays, such as urethane acrylate oligomers, epoxy acrylate oligomers, ester acrylate oligomers, and polyfunctional epoxy resins; Isobornyl acrylate, isobornyl methacrylate, dicyclopentenyl acrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl acrylate, dicyclopetanyl methacrylate, bornyl Acrylate, bornyl methacrylate, 2-hydroxyethyl acrylate, cyclohexyl acrylate, 2-hydroxypropyl acrylate, pheno Acrylic compounds such as ciethyl acrylate, morpholine acrylamide, morpholine methacrylamide, and acrylamide, and various monofunctional vinyl compounds such as N-vinyl pyrrolidone, N-vinyl caprolactam, vinyl acetate, and styrene; trimethylolpropane triacrylate, ethylene oxide Modified trimethylolpropane triacrylate, ethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, dicyclopenta Nyl diacrylate, polyester diacrylate, ethylene oxide modified bisphenol A diacrylate, Polyfunctional vinyl compounds such as taerythritol triacrylate, pentaerythritol tetraacrylate, propylene oxide modified trimethylolpropane triacrylate, propylene oxide modified bisphenol A diacrylate, tris (acryloxyethyl) isocyanurate; hydrogenated bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4 -Epoxycyclohexylmethyl) A photopolymerization initiator having a photopolymerization initiating action in the wavelength region of ultraviolet rays, and one or more of various epoxy compounds such as adipate, and the like. If necessary, an ultraviolet curable resin composition containing a sensitizer or the like can be used.

  The type of light source used (particularly the spectral distribution of the light emitted from the light source in the ultraviolet wavelength region), the wavelength of the ultraviolet light used to form the photocured resin layer (predetermined wavelength), and not used to form the photocured resin layer It is preferable to adjust the curing wavelength of the ultraviolet curable resin composition by ultraviolet rays according to the wavelength of ultraviolet rays to be shielded. Adjustment of the curing wavelength by ultraviolet rays of the ultraviolet curable resin composition includes, for example, the type of photopolymerization initiator (particularly optimum ultraviolet absorption wavelength) to be blended in the ultraviolet curable resin composition, and the ultraviolet curable resin composition. This can be done by selecting the type and composition of the polymer or monomer, the type of the sensitizer, the type or composition of the other components.

  Although not limited in any way, examples of the photopolymerization initiator that can be used in the ultraviolet curable resin composition used in the present invention include isobutyl benzoin ether (optimum UV absorption 240 to 270 nm), isopropyl benzoin ether (240 to the same). 270 nm), benzoin ethyl ether, benzoin methyl ether (300-380 nm) and other benzoin ether photopolymerization initiators; 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime (250- Α-acyloxime ester photopolymerization initiators such as 400 nm); benzyl ketal photopolymerization initiators such as 2,2-methoxy-2-phenylacetophenone (250 to 350 nm) and hydroxycyclohexyl phenyl ketone (250 to 319 nm) Agent: Diethoxy Cetophenone (240-350 nm), 2,2-dimethoxy-1,2-diphenylethane-1-one (310-390 nm), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (same) 200-300 nm) and other acetophenone derivative-based photopolymerization initiators; benzophenine (240-350 nm), chlorothioxanthone (275-400 nm), 2-chlorothioxanthone (200-400 nm), isopropylthioxanthone (250-400 nm) Benzoyl-based photopolymerization initiators such as 2-methylthioxanthone (250 to 400 nm) and halogen-substituted alkyl-aryl ketone (240 to 360 nm).

  The type of light source used for stereolithography (spectral distribution in the ultraviolet region of the light emitted from the light source), the wavelength of the ultraviolet rays used to form the photocured resin layer, and the shield without using the photocured resin layer A more suitable photopolymerization initiator may be selected according to the wavelength of ultraviolet rays and the like, and blended in the ultraviolet curable resin composition. When using an ultrahigh pressure mercury lamp or a high pressure mercury lamp as a light source, forming a resin layer photocured by ultraviolet rays having a wavelength of 365 nm or the vicinity thereof, and performing optical modeling by the above-described method of shielding ultraviolet rays having a wavelength of 340 nm or less 2,2-dimethoxy-1,2-diphenylethane-1-one [eg, “Irgacure (registered trademark) 651” manufactured by Ciba Specialty Chemicals, etc.], 2-hydroxy-2-methyl-1-phenyl- It is preferable to use an ultraviolet curable resin composition containing a photopolymerization initiator such as propan-1-one [eg, “Darocur (registered trademark) 1173” manufactured by Ciba Specialty Chemicals, etc.].

  The ultraviolet curable resin composition used in the present invention may further include a leveling agent, a surfactant other than a phosphate ester-based surfactant, an organic polymer modifier, an organic plasticizer, solid fine particles, if necessary. Contains one or more fillers such as inorganic fine particles such as carbon black fine particles, polystyrene fine particles, polyethylene fine particles, polypropylene fine particles, organic polymer fine particles such as acrylic resin fine particles, and synthetic rubber fine particles. You may do it. When a filler is contained, it is possible to improve dimensional accuracy by reducing volume shrinkage during curing, improve mechanical properties and heat resistance, and the like.

Hereinafter, the present invention will be specifically described with reference to FIG. 3, but the present invention is not limited to the one shown in FIG.
FIG. 3 shows a specific example of the main part of the optical modeling apparatus used for the optical modeling of the present invention.
In FIG. 3, 1 is a light source, and 2 is an ultraviolet ray having a wavelength different from the ultraviolet ray having a predetermined wavelength used for forming a photocured resin layer (not used for forming a photocured resin layer). A filter that absorbs and removes ultraviolet rays, 3 is a filter that transmits ultraviolet rays of the predetermined wavelength and absorbs infrared rays, 4 is a rod lens, 5 is a reflecting mirror, 6 is a Fresnel lens, 7 is a liquid crystal drawing mask, and 8 is a projection lens. Reference numerals 9 and 9 denote a modeling surface made of an ultraviolet curable resin composition.

  As shown in FIG. 3, among the light rays contained in the light from the light source 1, ultraviolet rays, visible rays and infrared rays having a predetermined wavelength used for forming the photocured resin layer pass through the filter 2, while the photocured resin. Ultraviolet rays not used for forming the layer (ultraviolet rays other than the predetermined wavelength) are absorbed by the filter 2 and removed. Next, among ultraviolet rays, visible rays, and infrared rays having a predetermined wavelength that have passed through the filter 2, infrared rays (typically infrared rays having a wavelength of 780 nm or more) are absorbed and removed by the filter 3, while ultraviolet rays and visible rays having a predetermined wavelength are filtered. 3 passes through the rod lens 4 and is turned by the reflection mirror 5, and is guided to the back of the liquid crystal drawing mask 7 through the Fresnel lens 6. At this stage, ultraviolet rays and infrared rays having wavelengths other than the ultraviolet rays having a predetermined wavelength included in the light from the light source 1 are removed or the amount thereof is greatly reduced. Deterioration of the liquid crystal drawing mask 7 is prevented or suppressed. The ultraviolet ray having a predetermined wavelength guided to the back of the liquid crystal drawing mask 7 passes through the liquid crystal drawing mask 7 in a predetermined pattern corresponding to the mask image of the liquid crystal drawing mask 7, passes through the projection lens 8, and is received from the ultraviolet curable resin composition. A photocured resin layer having a predetermined shape pattern corresponding to the mask image of the liquid crystal drawing mask 7 is irradiated on the modeling surface 9 to be formed on the modeling surface 9.

  In the optical modeling apparatus shown in FIG. 3, the mask image of the liquid crystal drawing mask 7 is information stored in advance in a computer corresponding to the shape pattern, structure, size, etc. of the optical modeling object for manufacturing. Correspondingly, among the plurality of minute liquid crystal shutters arranged on the liquid crystal drawing mask 7, the liquid crystal shutter positioned at a position where light should pass is opened so as to allow light to pass therethrough, and is positioned at a position where light should be shielded. The liquid crystal shutter is closed to prevent the passage of light, and such an operation is designed to be repeated until a photocured resin layer having a predetermined cross-sectional shape is formed (when manufacturing a three-dimensional model). .

In the stereolithography apparatus shown in FIG. 3, the filters 2 and 3 are disposed in the vicinity of the light source 1, but the present invention is not limited thereto, and may be disposed in the vicinity of the back surface of the liquid crystal drawing mask 7, for example. Alternatively, they may be arranged at other positions between the light source 1 and the liquid crystal drawing mask 7.
In the stereolithography apparatus shown in FIG. 3, the light from the light source 1 is guided to the liquid crystal drawing mask 7 through the rod lens 4, the reflecting mirror 5, and the Fresnel lens 6. 3 may be passed directly through the Fresnel lens 6 to the liquid crystal drawing mask 7 as it is.
Further, the arrangement order of the filters 2 and 3 may be reversed, or only the filter 2 excluding ultraviolet rays other than a predetermined wavelength may be arranged without arranging the filter 3 excluding infrared rays.

  The liquid crystal drawing mask 7 is not particularly limited, and a liquid crystal drawing mask having an appropriate shape can be adopted according to the shape and dimensions (particularly the cross-sectional shape and dimensions thereof) of the optically shaped object to be manufactured. The liquid crystal drawing mask 7 may be, for example, a square, a rectangle, or other shapes.

<< Test Example 1 >> [Endurance test of liquid crystal drawing mask against ultraviolet rays]
(1) The apparatus shown in FIG. 4 was used in order to conduct a durability test against ultraviolet rays of the liquid crystal drawing mask. In the apparatus of FIG. 4, reference numeral 1 denotes a light source [super-high pressure mercury lamp “YLT-MX200” manufactured by WILT; output 200 W], and 2 transmits ultraviolet light having a predetermined wavelength, but ultraviolet light having a shorter wavelength than that. Filter removed by absorption [“UTF-50S-34U” manufactured by Sigma Koki Co., Ltd .; UV transmittance (wavelength of i-line) of 365 nm and near UV transmittance of 80% or more, UV light shielding rate (absorption rate) of 340 nm ) About 50%, shielding rate (absorption rate) of ultraviolet light with wavelength of 320 nm or less is almost 100%], 3 is an infrared absorption filter [“KG 1” manufactured by Melles Griot; ultraviolet light (i-line) with wavelength of 365 nm and ultraviolet light nearby. Transmittance of 90% or more, shielding rate (absorption rate) of light with a wavelength of 800 nm is about 50%, shielding rate (absorption rate) of infrared ray with a wavelength of 1000 nm or more is almost 100%], 7 Indicates a liquid crystal drawing mask (VGA liquid crystal manufactured by Casio Computer Co., Ltd.), and 10 indicates a quartz fiber [made by Welty, diameter: 5 mm] for guiding light from the light source 1.

(2) Using the apparatus shown in FIG. 4, the spectrum shown in FIG. 1 is adopted under the condition that the irradiation intensity of ultraviolet rays with a wavelength of 365 nm used for forming a photocured resin layer becomes 1900 mJ / sec on average. When light from a light source 1 (super high pressure mercury lamp) having a distribution is continuously irradiated onto the liquid crystal drawing mask 7 through the quartz fiber 10, the filter 2 and the filter 3, the cumulative irradiance of ultraviolet light having a wavelength of 365 nm is 9400 J / cm ² . Even when it reaches, the liquid crystal drawing mask 7 can perform light-shielding and translucency driving (on-off driving) in a minute dot area as normal, and the cumulative irradiation illuminance of ultraviolet light having a wavelength of 365 nm is 12000 J / cm ² . when the reached was, finally, the driving of the light shielding and light transmitting in a minute dot area (oN - oFF driving) is impossible defective portion (area of approximately 25 mm ²⁾ of the liquid crystal draw It occurred in the mask surface.

(3) In the apparatus shown in FIG. 4, the filter 2 (the filter that absorbs and removes ultraviolet light having a wavelength shorter than 365 nm) is removed from the apparatus (without use), and the other conditions are the same as in (2) above. When the deterioration test by the ultraviolet rays of the liquid crystal drawing mask 7 was carried out, when the cumulative irradiation illuminance of the ultraviolet rays with a wavelength of 365 nm reached 2300 J / cm ² , the light shielding and the translucent driving ( A defective part (area of about 25 mm ² ) that cannot be turned on and off occurs on the liquid crystal drawing mask surface, and when the test is continued as it is, the area of the defective part reaches a cumulative irradiance of 7000 J / cm ² . expanding at the time of the in 75 mm ^2, it expanded significantly to the 125 mm ² at the time the cumulative irradiance reached 12000J / cm ^2.

(4) As is clear from the comparison of the results of (2) and (3) above, in the above (2), the filter 2 is used to form ultraviolet rays (wavelength 365 nm and its vicinity) used for forming a photocured resin layer. Of the other wavelengths (ultraviolet rays shorter than 365 nm) are cut to prevent exposure of the liquid crystal drawing mask 7 by ultraviolet rays shorter than 365 nm. Compared with the above (3) in which irradiation was performed while exposing the liquid crystal drawing mask 7 to ultraviolet light having a wavelength of 365 nm and the vicinity thereof and ultraviolet light having a shorter wavelength without using the filter 2 by performing the irradiation. The life of the liquid crystal drawing mask 7 is greatly extended.

Example 1
(1) Optical stereolithography was manufactured using the optical modeling apparatus shown in FIG.
In the stereolithography apparatus of FIG. 3, the same light source 1, filter 2, filter 3 and liquid crystal drawing mask 7 as those used in Test Example 1 were used. In addition, the rod lens 4 is “YLT-IRL25” manufactured by YELTY, the reflection mirror 5 is “cold mirror” manufactured by Koshin Kogyo Co., Ltd., and the Fresnel lens 6 is a Fresnel lens and projection lens manufactured by this special optical resin company. 8 used “EL-Nikkor” manufactured by Nikon Corporation. As the ultraviolet curable resin composition, “CPX-1000” [curing sensitivity: 2.5 mJ; ultraviolet curing wavelength: 365 nm; containing Irgacure (registered trademark) 651 as a photopolymerization initiator] was used.
(2) Using the optical modeling apparatus of FIG. 3 shown in (1) above, projection size onto the modeling surface 9 made of an ultraviolet curable resin composition = 40 mm × 30 mm, light energy intensity 2 on the modeling surface 9 Repeat the operation of forming a photocured resin layer by irradiating the modeling surface with light under the conditions of 0.5 mW / cm ² , irradiation time of 1 sec and irradiation depth of 0.1 mm, and length × width × height = A three-dimensional model having a size of 22 mm × 32 mm × 25 mm was manufactured (optical modeling time 1 hour).
(3) The three-dimensional structure obtained by the above (2) has a good appearance and excellent dimensional accuracy.

The stereolithography method and apparatus of the present invention prevents or suppresses deterioration of the liquid crystal drawing mask due to ultraviolet rays or ultraviolet rays and infrared rays, greatly extending the usable life of the expensive liquid crystal drawing mask, It is effective for economically producing a high-quality optically shaped object excellent in accuracy, mechanical properties, etc. at a high modeling speed, with high productivity, and at a lower cost than conventional ones.
The stereolithography method and apparatus of the present invention can be effectively used for the production of various three-dimensional models ranging from small to large.
In the case of the method and apparatus of the present invention, models for precision parts, electrical / electronic parts, furniture, building structures, automotive parts, various containers, castings, molds, mother molds, etc., complex models Parts for designing simple heat transfer circuits, parts for analysis and planning of heat transfer behavior of complex structures, other various three-dimensional objects with complicated shapes and structures, and planar photocured resin layers such as lithographs Can be manufactured smoothly with high modeling speed and dimensional accuracy.

It is a figure which shows the spectral distribution of the light radiated | emitted from an ultra high pressure mercury lamp. It is a figure which shows the spectral distribution of the light radiated | emitted from a high pressure mercury lamp. It is a figure which shows an example of the optical modeling apparatus of this invention. It is a figure which shows the test apparatus used by Test Example 1 (deterioration test by the ultraviolet-ray of a liquid crystal drawing mask).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 2 Filter for absorbing and removing ultraviolet rays having a wavelength different from the ultraviolet ray having a predetermined wavelength used for forming a photocured resin layer 3 Filter for absorbing and removing infrared rays 4 Rod lens 5 Reflecting mirror 6 Fresnel lens 7 Liquid crystal drawing Mask 8 Projection lens 9 Modeling surface made of UV curable resin composition 10 Quartz fiber

Claims (12)

Light is irradiated under control through a liquid crystal drawing mask in which multiple micro liquid crystal shutters that can block and transmit light in a micro dot area are arranged in a linear or planar manner on a modeling surface made of a photocurable resin composition Then, after forming a photocured resin layer having a predetermined shape pattern, a photocurable resin composition for one layer is applied on the photocured resin layer to form a modeling surface, and the photocurability A target three-dimensional model is formed by further irradiating light on the modeling surface made of the resin composition under control through a liquid crystal drawing mask to further form a photocured resin layer having a predetermined shape pattern. The optical shaping method is repeated until the formation of a photocured resin layer using an ultraviolet curable resin composition as a photocurable resin composition, and a wavelength of 300 to 390 nm of ultraviolet rays contained in light from a light source. predetermined wave is in the range of Optical modeling method is the ultraviolet the predetermined wavelength and performing while preventing or suppressing the exposure of the liquid crystal image drawing mask according to different UV wavelengths and performs the ultraviolet. Light is irradiated under control through a liquid crystal drawing mask in which multiple micro liquid crystal shutters that can block and transmit light in a micro dot area are arranged in a linear or planar manner on a modeling surface made of a photocurable resin composition And forming a photocured resin layer having a predetermined shape pattern by using an ultraviolet curable resin composition as the photocurable resin composition. Is performed with ultraviolet light having a predetermined wavelength within the wavelength range of 300 to 390 nm among the ultraviolet light contained in the light from the light source, and the exposure of the liquid crystal drawing mask by ultraviolet light having a wavelength different from that of the predetermined wavelength is prevented or suppressed. An optical modeling method characterized by being performed. More than 60% of ultraviolet rays having a predetermined wavelength within the wavelength range of 300 to 390 nm used for forming the photocured resin layer are allowed to pass upstream of the liquid crystal drawing mask , but the predetermined wavelength within the wavelength range of 300 to 390 nm. The liquid crystal drawing mask is exposed to ultraviolet light having a wavelength different from that of the predetermined wavelength used for forming the photocured resin layer by arranging shielding means for shielding 50% or more of other ultraviolet light having a wavelength different from that of the ultraviolet light. The optical modeling method according to claim 1, wherein a photocured resin layer is formed while preventing or suppressing UV. The shielding means allows 60% or more of the ultraviolet light having a predetermined wavelength in the range of 300 to 390 nm used for forming the photocured resin layer to pass through the ultraviolet light having the predetermined wavelength in the range of 300 to 390 nm. The stereolithography method according to claim 3, which is a filter that absorbs and / or reflects 50% or more of ultraviolet rays having a short wavelength. While passing 60% or more of ultraviolet rays having a predetermined wavelength within the wavelength range of 300 to 390 nm used for forming a photocured resin layer, the liquid crystal drawing mask is shielded from 40% or more of light rays having a wavelength of 780 nm or more. The optical modeling method according to any one of claims 1 to 4, further comprising: a shielding unit that performs the prevention and further prevents or suppresses exposure of the liquid crystal drawing mask by light having a wavelength of 780 nm or more. The ultraviolet ray having the predetermined wavelength in the range of 300 to 390 nm for forming the photocured resin layer rapidly cures the ultraviolet curable resin composition among the ultraviolet rays contained in the light from the light source. The optical modeling method according to any one of claims 1 to 5, wherein the optical shaping method has a light intensity capable of being reduced and has a relatively small deterioration effect on a liquid crystal drawing mask. Optical modeling method according to any one of claims 1 to 6 using a high intensity discharge lamp as a light source. As the photocurable resin composition, an ultraviolet curable resin composition that is at least cured by ultraviolet light having a wavelength of 365 nm or in the vicinity thereof but is not cured by visible light or infrared light having a wavelength of 400 nm or more is used. A shielding means for passing 60% or more of ultraviolet light having a wavelength of 365 nm or in the vicinity thereof contained in light emitted from an ultra-high pressure mercury lamp or a high-pressure mercury lamp and shielding 50% or more of ultraviolet light having a wavelength of 340 nm or less. arranged on the upstream side of the liquid crystal image drawing mask, while preventing or suppressing the exposure to wavelength 340nm UV light below the liquid crystal image drawing mask, claim the photocured resin layer formed by ultraviolet rays having a wavelength of 365nm or near 1-7 optical modeling method according to any one of. Means for forming a shaped surface comprising a photocurable resin composition;
A light source that emits light including ultraviolet rays of a predetermined wavelength and ultraviolet rays of other wavelengths in the range of a wavelength of 300 to 390 nm for curing the photocurable resin composition;
A liquid crystal drawing mask in which a plurality of minute light shutters capable of shielding and transmitting light in a minute dot area are arranged in a line or a plane; and
While passing more than 60% of ultraviolet rays with a predetermined wavelength and the curing the photocurable resin composition, to absorb and / or reflect more than 50% of ultraviolet rays having a wavelength other than the predetermined wavelength, the upstream side of the liquid crystal image drawing mask Shielding means arranged on;
An optical shaping apparatus comprising: The optical modeling apparatus according to claim 9 , wherein the light source is a high-intensity discharge lamp. The upstream side of the liquid crystal drawing mask allows 60% or more of ultraviolet rays having a predetermined wavelength within a wavelength range of 300 to 390 nm to cure the photocurable resin composition to pass, but shields 40% or more of light rays having a wavelength of 780 nm or more. a shielding means for further arranged, an optical modeling apparatus according to claim 9 or 10. Light source is an ultra-high pressure mercury lamp or high pressure mercury lamp, but pass more than 60% of the ultraviolet radiation of a predetermined wavelength and the curing the photocurable resin composition absorbs more than 50% of ultraviolet rays having a wavelength other than the predetermined wavelength and / or reflecting shielding means, one of the claims 9 to 11 which is a filter that absorbs and / or reflects more than 50% of the and wavelength 340nm following the light was passed through more than 60% of the UV wavelength 365nm or near the The optical modeling apparatus of Claim 1.

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