JP2007313509A - Laser beam lithographic method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam lithographic method which enables the manufacture of molded products having various shapes and structures without the need to mold extra components such as a support part and with excellent molding cycle. <P>SOLUTION: This laser beam lithographic method comprises the step of providing a resin composition for laser beam lithography, which causes a reversible and rapid sol-gel phase transition upon any physical change of the composition, and imparting "any physical change" to the resin composition to allow the resin composition to rapidly gel and, in this state, exposing the surface of the resin composition to light in a plotting way. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical modeling method for forming a three-dimensional model using a photocurable component.

  As the name suggests, the stereolithography method scans the liquid photocurable resin sequentially with laser light without using a mold at all, cures and laminates the resin in layers, and finally three-dimensional molding (Yoji Marutani et al., "Optical modeling method-3D plotter with laser", Nikkan Kogyo Shimbun). According to this method, for example, a skull model created by using the result of CT scan, a molded product having a shape that could not be produced by the conventional extrusion molding method or other plastic molding methods can be freely used. Can be produced. In recent years, the rapid modeling (rapid prototyping) has attracted attention both in Japan and overseas, and the stereolithography has become one of the typical modeling techniques.

  Here, the optical modeling method will be described more specifically. According to the optical modeling method, the surface of the resin composition for optical modeling method including the photocurable component is subjected to drawing light irradiation to perform the drawing. By repeating the operation of forming the corresponding cured resin layer, a three-dimensional shaped object formed by stacking a plurality of the cured resin layers is formed. For this reason, the three-dimensional shape to be modeled is analyzed using a computer or the like, and a sliced one of the three-dimensional shape is created and stored as a plurality of slice shape data. According to the above, a three-dimensional shaped article is formed by sequentially irradiating the surface of the resin composition for stereolithography with an ultraviolet laser, etc., and sequentially curing the resin composition to form a cured resin layer. Will be molded.

  For example, in Japanese Patent Laid-Open No. 56-144478, a liquid photocurable resin is accommodated in a container, and the surface of the photocurable resin is selected by scanning an exposure means provided on the upper part of the container. By irradiating light to form a cured resin layer, supplying one layer of photocurable resin on the cured resin layer to form a liquid resin layer, and selectively irradiating the surface with light A new cured resin layer is laminated integrally on the previously formed cured resin layer so as to be continuous therewith, and further, the supply of the photocurable resin and the light irradiation are repeated a predetermined number of times, A method for forming a shaped object is disclosed.

  However, in the method disclosed in Japanese Patent Laid-Open No. 56-144478, the uncured portion is in a liquid state, and therefore the uncured portion does not have the mechanical strength to support the cured portion. Therefore, for example, when forming a shaped object whose upper part is larger than the lower part, the upper part is likely to be deformed such as warping, and is composed of a plurality of discontinuous parts. Cannot be molded. In these cases, the support part for supporting the large upper part and the connecting part for maintaining the gap between the parts are formed excessively, and the supporting part or the connecting part is removed from the obtained preform. This requires a complicated process. Furthermore, it is composed of a plurality of discontinuous parts, such as a structure in which two or more gears engaged with each other are held in a box in a state where they can be driven, and smooth driveability to one or more of the parts However, there is a restriction that the manufacturing of the structure requiring the above is practically impossible.

As a method for overcoming the above problem, Japanese Patent Laid-Open No. 9-70897 discloses a stereolithography method that utilizes the cooling and solidification phenomenon of a photosensitive resin at room temperature or lower. In this method, a photosensitive resin that is liquid at room temperature is spread in layers, the spread layer is cooled below the freezing point of the photosensitive resin to form a solidified layer, and then a predetermined portion of the solidified layer is formed. A series of steps consisting of irradiating light to form a cured resin layer is repeated a predetermined number of times. According to this method, it is not necessary to mold the support portion and the connecting portion, and it is possible to manufacture a structure having a drive portion.
JP 56-144478 A JP-A-9-70897

  In the method disclosed in JP-A-9-70897, it is necessary to sufficiently reduce the viscosity of the resin by heating in advance in order to develop the photosensitive resin into a layer having a desired uniform thickness, After the development, in order to develop sufficient solidification strength in the photosensitive resin layer, it is necessary to sufficiently cool the layer over the entire surface, for example, by blowing liquid nitrogen. For this reason, the time required for a series of operations for forming a cured resin layer for one layer must be long. This tendency becomes more prominent as the number of operations is repeated, and the time required for completion of the shaped object becomes extremely long.

  The present invention has been made in view of the problems as described above, and the object thereof is excellent without requiring molding of extra parts such as support parts, etc., in various shapes and structures. Another object of the present invention is to provide an optical modeling method that can be manufactured in a molding cycle. Another object of the present invention is to produce a model having various shapes and structures by an optical molding method without requiring molding of extra parts such as a support part and an excellent molding cycle. An object of the present invention is to provide a resin composition for stereolithography that makes it possible.

  In order to solve the problems as described above, the stereolithography method according to the present invention is characterized by using a resin composition for stereolithography that rapidly causes a sol-gel phase transition. The resin composition for stereolithography is characterized by containing a resin component that causes a sol-gel phase transition when combined with a photocurable component.

[Optical modeling method according to the present invention]
More specifically, the present invention provides the following (A1) stereolithography.

  (A1) By repeating the operation of forming a cured resin layer corresponding to the drawing by performing drawing-like light irradiation on the surface of the resin composition for optical modeling method containing the photocurable component, the cured resin layer becomes An optical modeling method for forming a three-dimensional modeled object formed by stacking a plurality of layers, and the resin for optical modeling method that causes reversible and rapid sol-gel phase transition due to some physical change as the resin composition for optical modeling method Using the composition, the resin composition for stereolithography is rapidly gelled by applying the “some physical change”, and in this state, the surface is drawn on the surface of the resin composition for stereolithography. An optical modeling method comprising a step of performing simple light irradiation. In addition, “resin composition for optical modeling method causing reversible and rapid sol-gel phase transition due to some physical change” has a function of “reversibly and rapidly causing sol-gel phase transition due to some physical change” described later. It can be produced by including a reversible rapid phase change resin component having a resin composition.

  The stereolithography method (A1) includes any of the stereolithography methods (A2) to (A7) below.

  (A2) By repeating the operation of forming a cured resin layer corresponding to the drawing by performing drawing-like light irradiation on the surface of the resin composition for photofabrication method containing the photocurable component, the cured resin layer becomes An optical modeling method for forming a three-dimensional modeled object formed by stacking a plurality of layers, and the resin for optical modeling method that causes reversible and rapid sol-gel phase transition due to some physical change as the resin composition for optical modeling method Using the composition, the resin composition for stereolithography is rapidly gelled by applying the “some physical change” and directly on the surface of the resin composition for stereolithography in the gelled state. An optical modeling method comprising a step of drawing a predetermined mask pattern and performing light irradiation on the mask pattern.

  (A3) An n-th resin layer is formed by supplying one layer of a resin composition for stereolithography containing a photocurable component and causing a sol-gel phase transition reversibly and rapidly due to some physical change. A step of gelling the nth resin layer by some physical change, a step of drawing a predetermined mask pattern directly on the surface of the gelled nth resin layer, After the mask pattern is drawn, the nth resin layer is irradiated with light from above the mask pattern, and the nth resin layer is photocured along the mask pattern. Forming the n-th cured resin layer by the step, and supplying one layer of the resin composition for stereolithography on the n-th cured resin layer formed by this step. ) Forming a resin layer of the first layer Optical modeling method which is characterized the door.

  (A4) The stereolithography method according to any one of (A1) to (A3), wherein the “some physical change” is a temperature change.

(A5) Any of (A1) to (A4) above, wherein the resin composition for stereolithography contains a urethane acrylate, ester acrylate, epoxy acrylate, or epoxy photocurable resin as a photocurable component. The described stereolithography.

(A6) The optical modeling according to any one of (A1) to (A5), wherein the resin composition for optical modeling method contains a photocurable component, a syndiotactic polymethacrylic acid ester, and an isotactic polymethacrylic acid ester. Law.

(A7) The optical molding method according to (A6), wherein the resin composition for optical modeling method contains a photocurable component, syndiotactic polymethyl methacrylate, and isotactic polymethyl methacrylate.

[Photocurable components used in stereolithography]
The photocurable component used in the stereolithography includes what is also called a photosensitive resin, and is widely used as a resist during etching in a semiconductor manufacturing process, for example.

  In the optical modeling method according to the present invention, as a photocurable component, an oligomer having one or more functional groups in the molecule that can react with light irradiation to form a crosslinked structure, and one similar functional group in the molecule. Monomers having the above or both are used. Examples of the oligomer include radical polymerization photocurable resins such as unsaturated polyester resins, acrylic resins and ene / thiol resins, and cationic polymerization photocurable resins such as epoxy resins (of course. In addition, for example, a novolak resin mixed with a sulfonic acid ester of diazonaphthoquinone as a photosensitizer can also be used. Among these, acrylic resins, particularly ester acrylates, urethane acrylates, and epoxy acrylates are suitable as oligomers contained in the resin composition for optical modeling methods according to the present invention. Examples of the monomer include radical polymerizable monomers such as acrylic esters and methacrylic esters, and cationic polymerizable monomers such as epoxy-containing compounds. Among these, radically polymerizable monomers are preferred from the viewpoints of curing speed and physical properties after curing.

  The resin composition for stereolithography according to the present invention may contain a small amount of a photosensitizer (such as a nitro compound, a quinone, or a ketone) so that the photoreaction occurs quickly. The resin composition for stereolithography according to the present invention contains a filler (reinforcing agent), a plasticizer, a stabilizer, a colorant, a flame retardant, an antioxidant, or an antistatic agent. Also good.

  Here, the resin composition that can be used as the resin composition for stereolithography according to the present invention or the resin composition suitable as the resin composition for stereolithography according to the present invention is as follows.

  (B1) A photocurable component that is cured by light irradiation, and a rapid phase change resin component that has a function of rapidly causing a phase transition from a sol to a “gel that can be differentiated from a photocured part” by some physical change. And a resin composition for stereolithography.

  (B2) A resin for optical modeling, comprising a photocurable component that is cured by light irradiation, and a reversible rapid phase transition resin component that has a function of causing a sol-gel phase transition reversibly and rapidly due to some physical change. Composition.

  (B3) The resin composition for stereolithography according to (B2), wherein the “some physical change” is a temperature change.

  (B4) The stereolithography according to (B2) or (B3) above, wherein the reversible rapid phase transition resin component is a mixture of syndiotactic polymethacrylate and isotactic polymethacrylate Legal resin composition.

  (B5) The resin composition for stereolithography according to (B4), wherein the reversible rapid phase transition resin component is a mixture of syndiotactic polymethyl methacrylate and isotactic polymethyl methacrylate.

  (B6) The (B2), (B3), (B4) or (B5), wherein the photocurable component is a urethane acrylate, ester acrylate, epoxy acrylate, or epoxy photocurable resin ) Resin composition for stereolithography.

  In the present invention, the following “usage” concept is also included in the scope.

  (B7) A method of using a reversible rapid phase transition resin having a function of reversibly and rapidly causing a sol-gel phase transition due to a temperature change for producing a resin composition for stereolithography.

  (B8) The resin composition for stereolithography according to (B7), wherein the reversible rapid phase transition resin is a mixture of syndiotactic polymethacrylate and isotactic polymethacrylate. Usage for manufacturing.

  (B9) The reversible rapid phase transition resin is a mixture of syndiotactic polymethyl methacrylate and isotactic polymethyl methacrylate. Usage for.

[Definition etc.]
Regarding the “rapid phase change resin component”, “a rapid phase change resin component having a function of causing a phase transition from a sol to a“ gel that can be differentiated from a photocured part ”by some physical change”, or , “Reversible rapid phase transition resin component having a function of causing reversible and rapid sol-gel phase transition due to some physical change”, and when the rapid phase transition resin component is mixed with a photocurable component, Due to the physical interaction with at least a part of the photocurable component, the state of “glass transition” as observed in ordinary resins is not observed, but “phase transition from sol to gel” or “from gel It is a component that expresses the property that the phase transition to sol occurs rapidly. More specifically, for example, a normal resin gradually softens from the glass transition temperature (Tg) as the temperature is raised. ”Is a temperature, the resin composition containing the rapid phase transition resin component and the photocurable component does not exhibit a“ glass transition ”state even when the temperature is gradually increased. (Therefore, the glass transition temperature is not observed), and at a specific temperature (Tp), the viscosity rapidly decreases and sol is formed (FIG. 1).

  Here, "some physical change" means something like temperature change or light irradiation. In the case of "temperature change", the temperature change from high temperature to low temperature is also the temperature change from low temperature to high temperature. Both changes are included.

  “A gel that can be differentiated from a photocured part” means that, for example, when immersed in a certain solvent, the photocured part does not dissolve while the gelated part that is not photocured dissolves. Means the case.

  In this specification, “component” means an element necessary for realizing the optical modeling method in the entire resin composition for optical modeling method, and the element (ie, “component”) is a pure substance. It may also be a mixture.

  “Drawing light irradiation” is performed in accordance with a slice pattern formed by slicing a three-dimensional shape of a molded product to be created. In the present invention, the resin composition for the optical modeling method is made corresponding to the slice pattern. A method comprising irradiating light from above a mask pattern directly formed on an object, via a mask pattern (for example, a negative film) corresponding to a slice pattern provided separately from a resin composition for stereolithography This is performed by a method comprising irradiating light and a method comprising scanning a laser beam corresponding to the slice pattern.

  “Irradiated light” to be used for light irradiation is light including a specific wavelength that can photocure the resin composition for optical modeling method to be used for optical modeling method. Ultraviolet rays, visible rays, and the like are used, but in many cases, ultraviolet rays are used. When light is irradiated after the mask pattern is directly drawn on the resin, there is no distance between the mask and the resin surface, so there is no need to consider the spread of light. Therefore, the “irradiation light” used in this case does not need to be parallel light as long as it has a predetermined intensity capable of photocuring the resin composition for stereolithography.

  The material for forming the “mask pattern” may reflect or absorb the “irradiation light” as long as it can block the “irradiation light” used for light irradiation. The material for directly forming the “mask pattern” on the resin is preferably a liquid in consideration of the convenience of application, but in some cases, it may be a solid such as a powder. Also good.

  As described above, according to the present invention, it is possible to manufacture a model with various shapes and structures without forming an extra part such as a support part and in an excellent molding cycle. An optical modeling method is provided.

  In addition, according to the present invention, it is possible to manufacture a model with various shapes and structures by an optical molding method without requiring molding of extra parts such as a support part and in an excellent molding cycle. A resin composition for stereolithography is provided.

  Speaking of the case of adopting a method of irradiating light from above a mask pattern directly formed on a resin composition for stereolithography, since ordinary photocurable components are photocured by ultraviolet rays, ultraviolet light blocking is performed. The layer is drawn directly on the exposed surface of the resin composition, and after light irradiation, the resin composition is further supplied and laminated thereon. For this purpose, the ultraviolet light blocking layer must be fixed to the exposed surface and have a thickness (about several microns) that does not affect the accuracy in the height direction.

  As a result of the inventors searching for what satisfies such conditions, and through repeated trial and error, an ink jet recording method that is currently used in ink jet printers that are generally distributed as printers for personal computers is used. It has been found suitable to employ. In the case of adopting the ink jet recording method, instead of ink, a component obtained by dispersing a component that blocks ultraviolet light (ultraviolet light blocking component) such as ultrafine titanium oxide may be used.

  In addition, as an ultraviolet light blocking component, not only an inorganic material such as the above ultrafine titanium oxide, but also an organic compound that absorbs ultraviolet rays such as polyglycidyl methacrylate can be used. Other UV light blocking components include 2-hydroxybenzophenone UV inhibitors, triazole UV inhibitors, salicylic acid derivative UV inhibitors, acrylonitrile derivative UV inhibitors, and other intramolecular rearrangements by absorbing UV light. It is also possible to use a compound that is stabilized by the formation of a chromophore or an auxiliary chromophore in an aromatic derivative.

[Resin Composition for Stereolithography According to the Present Invention]
If the method of irradiating light from the top of the mask pattern directly formed on the resin composition for stereolithography in the stereolithography according to the present invention is adopted, the ultraviolet light shielding to the resin composition for stereolithography is performed. It is also necessary to consider the fixability of the components. In addition, supply is performed under the temperature at the time of supply so that the step of supplying the resin composition for optical modeling method further proceeds smoothly on the photocured resin composition for optical modeling method. However, those skilled in the art can easily make such adjustments by appropriately controlling the amount and type of monomers classified as photocurable components. Can be done. When the resin composition for stereolithography is one that undergoes a phase transition rapidly due to a temperature change, the phase transition temperature (Tp in FIG. 1) is slightly higher than room temperature (for example, within a range of 50 to 100 ° C.). The temperature of the

  As a reversible rapid phase transition resin component having a function of causing a sol-gel phase transition reversibly and rapidly due to a temperature change, it has a function of causing a phase transition from sol to gel as the temperature decreases. Syndiotactic polymethacrylates such as syndiotactic polymethyl methacrylate, syndiotactic polyisobutyl methacrylate, syndiotactic polybenzyl methacrylate, syndiotactic polymethacrylic methacrylate, and isotactic polymethyl methacrylate Mixtures composed of tactic polymethacrylic acid esters are known (for example, JP-A-4-6562, JP-A-4-225209, JP-A-6-332176, JP-A-7-281426, JP-A-8-2816 9 JP, J.SPEVACEK and B.SCHNEIDER, AGGREGATION OF STEREOREGULAR POLY (METHYL METHACRYLATES), etc. Advances in Colloid and Interface Science, 27 (1987) 81-150). In addition, when using a mixture composed of syndiotactic polymethacrylic acid ester and isotactic polymethacrylic acid ester as a reversible rapid phase transition resin component, a photocurable component constituting the resin composition for stereolithography, Suitable relative amounts in syndiotactic polymethacrylates and isotactic polymethacrylates are: photocurable component type, syndiotactic polymethacrylate type and stereoregularity, isotactic polymethacrylate Since it depends on conditions such as the type and stereoregularity, it is preferable to determine experimentally as appropriate.

  Further, reversible rapid phase transition resin components that cause a phase transition from a sol to a gel with an increase in temperature are also known (JP-A-9-192469, JP-A-9-227329, JP-A-10-77201, JP-A-10-101518, JP-A-11-169703).

[Optical modeling process]
According to the stereolithography method according to the present invention, one layer of the resin composition for stereolithography method is extruded onto a predetermined lift and solidified (gelled), and drawn on the surface of the solidified composition. By repeating selective light irradiation and repeating the process of extruding one layer of the resin composition for stereolithography onto the cured layer (for example, after extruding and solidifying, the solidification A process of drawing a mask pattern directly on the surface of the composition in a finished state, then photocuring, and further extruding one layer of the resin composition for stereolithography onto the cured layer while leaving the mask pattern repeat). Then, after all the three-dimensional shapes to be formed are photocured, the uncured gel portion is removed to finally obtain a three-dimensional shape to be modeled.

  Here, the resin composition for stereolithography includes a rapid phase transition resin component having a function of rapidly causing a phase transition from a sol to a “gel that can be differentiated from a photocured portion” by some physical change. When the resin composition for stereolithography is used and the phase transition of the resin composition is an irreversible phenomenon, the uncured gel portion can be removed using a predetermined solvent or the like. On the other hand, when a resin composition for stereolithography containing a reversible rapid phase transition resin component having a function of causing reversible and rapid sol-gel phase transition due to some physical change is used, the physical change is imparted. By making the uncured gel part into a sol and making it flowable, the gel part can be removed (for example, when the temperature rapidly raises the phase transition from gel to sol) Can be heated to form a sol and flowable). Here, when the gel portion is removed as a sol, the sol may be removed by swelling or dissolving in a solvent, and after the removal, the obtained three-dimensional model may be washed with a solvent. Good. In addition, after an uncured part is removed, further curing may be performed by further irradiating light to the obtained three-dimensional structure, and physical properties such as strength may be improved.

  Hereinafter, preferred embodiments of the present invention will be described. In addition, in the modeling method according to the present invention, it is important that the photocurable component and the rapid phase transition resin component contained in the resin composition for optical modeling method have the function, and have the function. As long as it does not depend on the type of substance, it is clear that the modeling method according to the present invention is not limited to the type of resin composition for optical modeling method used in this example. Moreover, in the resin composition for stereolithography according to the present invention, each component only needs to be included in an amount and manner capable of exhibiting a function for carrying out the modeling method according to the present invention. The resin composition for stereolithography is not limited to the composition ratio used in this example.

  In this example, a prototype system was designed and manufactured in order to confirm its usefulness and effectiveness (FIG. 2). In this prototype system, as a resin composition for stereolithography, a composition that is in a gel state at room temperature and changes to a sol state at about 80 ° C. (urethane acrylate UV curable resin: syndiotactic polymethyl methacrylate: isotactic) Tic polymethyl methacrylate = 75: 16.7: 8.3 (weight ratio)) was used. And when supplying this resin composition for optical modeling methods, a certain amount of the composition stored as a sol state under conditions of 80 ° C. or higher was extruded onto an elevator and supplied in a plane by a recoater.

  When it did in this way, the composition supplied on the elevator gelatinized in about 30 second under normal temperature conditions. Then, a mask pattern made of an ultraviolet light blocking layer was drawn on the surface of the composition transformed to the gel state using an inkjet head, and exposed to an ultraviolet lamp. Further, while leaving the mask pattern, one layer of the resin composition for optical modeling method was extruded onto the layer subjected to the light irradiation treatment. And the target shape was obtained by repeating this. After completion of modeling, the resulting block in the gel state is heated in a solvent such as toluene to which ultrasonic vibration is applied at about 80 ° C. for about 3 hours to remove the end-cured resin, and finally post-exposure is performed. I went and got a model.

  The above process will be described more specifically with reference to FIG. 2 as follows.

  Here, since the resin after the supply in the above (3) changes to a gel state in a short time of about 0.5 to 1 minute, the step (4) is facilitated as described above. . According to the above table, after the above (5) is performed, the elevator is further lowered, and the steps (3) to (5) are repeated as many times as necessary without removing the mask pattern. , Removing the uncured resin, and finally post-exposure to obtain a shaped article.

  The procedure of the stereolithography method according to this example is basically the same as the procedure disclosed in Japanese Patent Laid-Open No. 9-70897, but as described above, using the rapid phase transition resin component. The difference is that a mask pattern is directly drawn on a resin composition that has been gelled (solidified) by phase transition.

  And, since the mask is directly drawn on the exposure surface, there is an advantage that there is little error in the cured shape due to the spread of ultraviolet light, and the ultraviolet light blocking layer (n layers of ultraviolet light) drawn in each layer and left as it is. The blocking layer (mask pattern)) further has an advantage of blocking the transmitted light from the layer ((n + 1) layer) thereabove and completely suppressing the excessive growth in the depth direction.

  This will be described in more detail with reference to FIG. 3. When attempting to form a three-dimensional solid as shown in FIG. 3A, one layer of the resin composition for optical modeling is extruded. First, a lower three-stage part is produced by repeating the process of irradiating light without a mask and curing the resin three times (FIG. 3B). Then, when the uppermost part is an n layer, one layer of the resin composition for optical modeling method is extruded on the n layer to form an (n + 1) layer, and the (n + 1) layer is solidified (gelled). (FIG. 3 (C)), a mask pattern 21 is directly drawn on a part of the (n + 1) layer (FIG. 3 (D)). (FIG. 3E). Then, since the lower side of the mask pattern 21 is shielded by the mask pattern 21, no photocuring occurs, and only the exposed portion 22 is photocured (FIG. 3E).

  Then, without removing the mask pattern 21, one layer of the resin composition for optical modeling method is extruded from above to form the (n + 2) th resin layer (FIG. 3F). Next, when light is irradiated from above the (n + 2) layer in this state, the irradiation light cannot pass through the mask pattern 21 even though it passes through the (n + 2) layer, and is below the mask pattern 21 in the (n + 1) layer. The portion is not photocured (FIG. 3G). For this reason, it is possible to completely suppress the excessive growth in the depth direction (in this example, the excessive growth with respect to the (n + 1) layer), which is regarded as a problem in general stereolithography. Therefore, the (n + 2) layer can be completely photocured in a state where the portion below the mask pattern 21 in the (n + 1) layer is not photocured and no excessive growth occurs on the (n + 1) layer. (FIG. 3 (H)).

  Returning to the process of FIG. 3, the part of the state of FIG. 3 (H) is immersed in a predetermined solvent, and when the temperature is raised, the portion of the (n + 1) layer under the mask pattern 21 that is not photocured. Becomes a sol and dissolves in the predetermined solvent to form a cavity 24, and a three-dimensional solid as shown in FIG. 3A is formed.

  In this case, the mask pattern 21 drawn thereon is also removed together with the (n + 1) layer portion under the mask pattern 21 that is not photocured. And the bottom surface 23 of the (n + 2) layer after these are removed becomes substantially flat. This is an epoch-making thing in the optical modeling method in which control in the depth direction is difficult and basically only the uneven bottom surface can be produced.

  In addition, the present inventors have already succeeded in modeling a gear body as shown in (1) of FIG. 2, and it was confirmed that high-resolution modeling can be performed in the XY axis direction and the depth direction. . Furthermore, the present inventors have actually made a pair of gears in the non-assembleable sample in which two gears mesh with each other using a prototype system similar to the above (the one shown in FIG. 2 (1)). We have also experimented with modeling such a thing, and succeeded in freely rotating the two gears after post-processing. In addition, the conventional method succeeds in modeling two opposing plates with a clearance of 100 μm in the height direction by drawing a mask on the upper surface of the layer corresponding to the bottom of the overhanging portion where excess growth occurs. did.

  In addition, for example, as shown in (1) of FIG. 2, the gear portion and the frame portion are not separable, and cannot be assembled starting from separate members. However, it is an advantage of the conventional optical modeling method that such a device can be manufactured integrally, and this advantage is not lost in the optical modeling method according to the present invention.

  As described above, according to the optical modeling method according to the present invention, it is confirmed that a high degree of freedom and high-resolution modeling in the height direction can be realized while taking advantage of the conventional optical modeling method. It was.

  Summarizing the above, it can be said that the following effects can be obtained according to the optical modeling method according to this embodiment.

1. A resin composition based on a glass transition that has been conventionally known by causing a component that rapidly causes a sol-gel phase transition by some physical change when mixed with a photocurable component in a resin composition for stereolithography. Compared with the stereolithography method using the solidification phenomenon of an object, the time required for the cooling process is shortened, and the time required for the entire stereolithography operation can be greatly reduced. In addition, since the cooling facility can be reduced in size and weight, the stereolithography apparatus can be reduced in size and price.

2. Since the uncured part is a gel, it has moderate strength, so it does not require molding of extra parts such as a support part and a connecting part, and has a complicated shape such as a structure with a drive part. The range of application of the optical modeling method is widened, for example, it becomes possible to manufacture a modeled structure.

3. Since a component (rapid phase transition resin component) that does not directly participate in the photocuring reaction is added to the resin composition for photofabrication method, the dimensional stability before and after photocuring increases, and the resulting molded product Dimensional accuracy can be improved.

4). Unlike beam scanning, uniform light exposure with a uniform cross section can be performed by parallel light exposure via an ultraviolet light blocking layer drawn directly on the surface of the resin layer. Further, the exposure time for each layer is constant.

5. The ultraviolet light blocking layer enables high-accuracy additive manufacturing by controlling the exact curing depth of each layer and avoiding excessive curing.

6). By increasing the ultraviolet light reflectivity of the ultraviolet light blocking layer, it becomes possible to bring uneven exposure in one layer closer to a uniform state.

It is a figure for demonstrating operation | movement and a function of a rapid phase change resin component. It is a figure for demonstrating the optical shaping method which concerns on an Example. It is a figure for demonstrating the effect of this invention.

Explanation of symbols

21 mask pattern 22 part exposed from mask pattern 23 lower surface of (n + 2) layer 24 cavity

Claims (1)

By repeating the operation of forming a cured resin layer corresponding to the drawing by irradiating the surface of the resin composition for optical modeling method containing the photocurable component with drawing light, a plurality of the cured resin layers are laminated. An optical modeling method for forming a three-dimensional model,
Using the resin composition for stereolithography that causes a sol-gel phase transition reversibly and rapidly due to some physical change as the resin composition for stereolithography,
The resin composition for stereolithography is rapidly gelled by applying the “some physical change”, and in this state, the surface of the resin composition for stereolithography is irradiated with drawing light. An optical modeling method characterized by including a process.

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