JPH08174680A - Optical shaping method - Google Patents

Abstract

PURPOSE: To obtain a laminate reduced in surface roughness by forming the N-th cured layer to draw up the same on the surface of a photosensitive resin soln. and curing the photosensitive resin soln. stagnated at the difference-in-level part of the N-th and (N--1)-th cured layers to draw down the same to the forming position of the (N+1)-th layer. CONSTITUTION: After the N-th cured layer 7 is formed, a base plate 3 is raised to draw up a laminate 10 so that the cured layer 7 appears on the surface of a photosensitive resin soln. 4 and the photosensitive resin soln. 4 stagnated at the difference-in-level part of the N-th cured layer 7 and the (N-1)-th cured layer 8 is irradiated with light 5 according to the shape of the cured layer 8 to be cured. As a result, a laminate free from difference in level is obtained. Next, the base plate 3 is sunk to lower than laminate 10 to the forming position of the (N+1)-th 9 layer to place the photosensitive resin soln. 1 on the N-th cured layer 7 in the thickness corresponding to one layer. Next, the (N+1)-th cured layer 9 is formed by the irradiation with light to be bonded to the N-th cured layer 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a laminate having a three-dimensional shape by a lamination method using a photosensitive resin liquid.

[0002]

2. Description of the Related Art As a method for forming a three-dimensional shape using a photosensitive resin, the shape to be formed is made into contour contour profile data by using a computer or the like, and an ultraviolet laser is selectively used as the photosensitive resin according to the contour data. There is known a stereolithography method of irradiating the surface of a sheet with the composition to polymerize and cure it, and then forming the layer by lamination.

[0003]

By the way, the main field of application of the stereolithography method in the industrial field is the manufacture of design models and the like. In these fields, the quality of the curved surface of the molded body is a problem, and smoothness of the model surface is expected. However, in the modeling method as described above, since the three-dimensional shape is divided into a plurality of thin layers, a step is generated on the model surface, and the smoothness of the surface is impaired. In particular, the smaller the inclination angle of the model surface, the greater the surface roughness.

Further, when a model is formed by using the modeling model formed by the optical molding method as a base model and the shape is transferred to a different material, the step is directly transferred. In addition, there was a problem that a step was caught at the stage of mold making and the mold could not be made well.

As a method of solving these problems, there is a method of reducing the step by reducing the layer thickness. However, when the layer thickness is reduced and the number of layers is increased by n times, for example, the surface roughness becomes about 1 / n, but at the same time, the modeling time is n times.
Double.

For this reason, conventionally, the steps on the surface of the laminate obtained by the stereolithography method are eliminated by secondary processing to smooth the surface.

[0007]

As described above, the present invention has the following features.
An object of the present invention is to provide an optical molding method capable of molding a laminate having a small surface roughness and a small step between each cured layer, and irradiating the surface of a photosensitive resin liquid with light. In the optical molding method of forming a cured layer by laminating a plurality of the cured layers to form a laminate having a desired three-dimensional shape, (A-1) irradiating the photosensitive resin with light to form the Nth layer. A step of forming a hardened layer, (B-1) by pulling up the laminate so that the Nth hardened layer is exposed above the liquid surface of the photosensitive resin, and the (N-1) th hardened layer A step of allowing the photosensitive resin liquid to stay in the step portion with the cured layer of the second layer, (C-1) N
A step of curing the photosensitive resin liquid accumulated in the step portion while the cured layer of the second layer is exposed on the photosensitive resin liquid surface, (D-
1) A stereolithography method including a step of pulling down the laminated body to a position where the (N + 1) th layer is formed.

The above object is to provide an optical molding method in which a surface of a photosensitive resin liquid is irradiated with light to form a cured layer, and a plurality of the cured layers are laminated to form a laminate having a desired three-dimensional shape. (A-2) A step of irradiating the photosensitive resin with light to form an Nth cured layer, and (B-2) laminating the Nth cured layer so as to appear above the liquid surface of the photosensitive resin. The step of allowing the photosensitive resin liquid to stay in the step portion between the Nth cured layer and the (N-1) th cured layer by pulling up the body, and (C-2) the Nth cured layer is exposed. Of the photosensitive resin liquid staying in the step portion while being exposed on the surface of the photosensitive resin liquid to cure the photosensitive resin, and the (D-2) laminated body is formed into the (N + 1) th layer. It can also be achieved by a stereolithography method that includes a step of pulling down to the position where it is formed.

Another object of the present invention is to provide an optical molding method in which a surface of a photosensitive resin liquid is irradiated with light to form a cured layer, and a plurality of the cured layers are laminated to form a laminate having a desired three-dimensional shape. , (A-3) a step of irradiating the photosensitive resin with light to form at least a part of the Nth cured layer, (B-3) applying the Nth cured layer onto the photosensitive resin liquid surface. By pulling up the laminate so as to appear in the
1) A step of allowing the photosensitive resin liquid to stay in the step portion with the cured layer of the 1st layer, and (C-3) the (N-1) layer with the cured layer of the Nth layer exposed on the surface of the photosensitive resin liquid. A step of irradiating light according to the shape of the cured layer of the eye to cure the photosensitive resin staying in the step portion and the uncured photosensitive resin of the Nth layer, (D-3) the laminated body ( It can also be achieved by an optical modeling method including a step of pulling down to the position where the (N + 1) th layer is formed.

[0010]

According to the stereolithography method of the present invention, after the Nth cured layer is formed, the Nth cured layer is pulled up onto the photosensitive resin liquid surface,
The photosensitive resin is retained in the step portion between the Nth cured layer and the (N-1) th cured layer, and the photosensitive resin retained in the step portion is cured in this state. It is possible to form a laminate having a smooth surface with almost no step between layers.

[0011]

DETAILED DESCRIPTION OF THE INVENTION A stereolithography method according to the present invention will be specifically described below with reference to the drawings. FIG. 1 is a diagram schematically showing a manufacturing process of a stereolithography method according to the present invention. FIG. 2 is a schematic perspective view of the evaluation model manufactured in the manufacturing example. Reference numeral 21 in FIG. 2 denotes a surface having an inclination of 10 degrees,
2 is a surface having an inclination of 20 degrees, 23 is a surface having an inclination of 30 degrees, 24 is a surface having an inclination of 40 degrees, 25 is a surface having an inclination of 50 degrees, and 26 is 6
A surface having an inclination of 0 degree, a surface 27 having an inclination of 70 degrees, and a surface 28 having an inclination of 80 degrees,
Reference numeral 29 is a surface having an inclination of 90 degrees.

In the stereolithography method according to the present invention, first, a step of irradiating the photosensitive resin 1 with light 5 to form the Nth cured layer 7 (hereinafter referred to as "step (A-1)") is performed. Elevator 2
By pulling down, the photosensitive resin 1 having a thickness of one layer is wrapped around the laminated body 10 (or the base plate 3), the Nth layer is drawn by the light 5, and the photosensitive resin is cured.
The hardened layer 7 of the Nth layer is formed while the hardened layer 7 of the layer is formed.
And (N-1) th hardened layer 8 are joined. That is, as shown in FIG.
The photosensitive resin 1 having the layer thickness is wrapped around, the N layer is drawn by the light 5, and the photosensitive resin 1 is cured.

In the present invention, any of the conventionally known photosensitive resins can be used as the photosensitive resin. Further, as the light for curing the photosensitive resin, infrared rays, visible rays, ultraviolet rays, ultraviolet lasers, etc. are used, depending on the photosensitive resin used.

Next, by pulling up the laminate 10 so that the Nth cured layer 7 is exposed on the surface of the photosensitive resin liquid, the Nth cured layer 7 and the (N-1) th layer are obtained. A step (hereinafter referred to as “step (B-1)”) of retaining the photosensitive resin liquid in the step portion with the cured layer 8 is performed. Then, the Nth cured layer 7
Of curing the photosensitive resin liquid 4 accumulated in the step portion in a state in which the photosensitive resin liquid is exposed on the surface of the photosensitive resin liquid (hereinafter referred to as “step (C-
1) ”)). That is, for example, as shown in FIG. 1B, the base plate 3 is raised and the light 5 is applied to the Nth hardened layer according to the shape of the (N−1) th hardened layer 8.

When the laminate 10 is pulled up so that the Nth cured layer 7 is exposed above the liquid surface of the photosensitive resin, the peripheral portion of the Nth cured layer 7 and the (N-1) th cured layer. The photosensitive resin liquid stays in the step portion with respect to 8 to fill the step and form a slope.
When the staying photosensitive resin liquid 4 staying in the step portion is cured, a laminated body having almost no step is obtained.

The width for pulling up the laminate 10 is as shown in FIG.
In the present invention, the width for pulling up the laminate 10 is not particularly limited as long as it is the thickness of the cured layer. It is preferable that the width for pulling up the laminated body 10 is equal to or more than the thickness of the cured layer, because unnecessary photosensitive resin flows down.

Next, a step of pulling down the laminated body 10 to a position where the (N + 1) th layer is formed (hereinafter referred to as "step (D-1)") is performed. By pulling down the laminated body 10 to a position where the (N + 1) layer is formed, the laminated body 10 is placed on the N-th laminated body 7 by one.
The photosensitive resin 1 having a layer thickness is made to wrap around. That is,
As shown in FIG. 1C, the base plate 3 is moved to the next (N
+1) Submerge to the depth to form the layer.

Then, as shown in FIG. 1 (d), (N +
1) Draw a layer to cure the photosensitive resin and bond it to the underlying cured layer. When pulling down the laminated body 10 to the position where the (N + 1) th layer is formed, the laminated body 10 is once lowered below the position where the (N + 1) th layer is formed, and then the laminated body 10 is lowered to the (N + 1) th layer. You may pull up to the position to form.

When the (N + 1) th layer is drawn with light 5, the photosensitive resin 1 is cured to form the (N + 1) th cured layer 9, and the Nth cured layer 7 and the (N + 1) th layer are also cured. The hardened layer 9 is joined.

A three-dimensional model can be formed by repeating the steps (A-1), (B-1), (C-1) and (D-1) up to the final layer of the shape. In addition,
When irradiating with light, it is desirable that the staying photosensitive resin liquid does not move.

In the stereolithography method of the present invention, after the Nth cured layer is formed, the Nth cured layer is raised, and an uncured photosensitive resin is applied to the peripheral portion of the Nth cured layer. Since the uncured photosensitive resin is allowed to stay and is cured, a laminate having almost no step can be formed.

Although the stereolithography method according to the present invention has been described above, the present invention is not limited to the above examples, and various modifications can be made within the scope of the technical idea of the present invention. For example, it can be performed as follows.

First, the step of forming the Nth hardened layer (hereinafter referred to as "step (A-2)") is performed in the same manner as the step (A-1). Next, as in the step (B-1), the N
By pulling up the laminate so that the cured layer as the second layer is exposed above the liquid surface of the photosensitive resin, the cured layer as the Nth layer and (N-1)
A step (hereinafter referred to as “step (B-2)”) of retaining the photosensitive resin liquid in a step portion with the cured layer of the first layer is performed.

Subsequently, with the N-th cured layer exposed on the surface of the photosensitive resin liquid, only the photosensitive resin staying at the step is irradiated with light, and the photosensitive resin liquid staying at the step portion is irradiated. Is performed (hereinafter referred to as “step (C-2)”).

Then, similarly to the step (D-1), a step of lowering the laminated body to a position where the (N + 1) th layer is formed (hereinafter referred to as "step (D-2)") is performed. The step (A-
2), step (B-2), step (C-2) and step (D-2)
By repeating the process up to the final layer of the shape, a three-dimensional model can be formed.

Also by such a method, after the Nth hardened layer is formed, the Nth hardened layer is raised so that the uncured photosensitive resin remains at the peripheral portion of the Nth hardened layer. Then, since the uncured photosensitive resin is cured, it is possible to obtain the same effect as the above.

The stereolithography method of the present invention can be further modified, and can be carried out as follows, for example. First, a step of irradiating the photosensitive resin with light to form at least a part of the Nth layer (hereinafter referred to as “step (A-3)”) is performed. By pulling down the elevator, a photosensitive resin having a thickness of one layer is made to wrap around on the laminated body (or on the base plate), and at least a part of the Nth layer is drawn by light to cure the photosensitive resin to cure the N layer. Form at least a portion of the eye. Here, only the peripheral portion of the N-th layer is cured, the entire surface of the N-layer light irradiation pattern is cured into a plurality of continuous or discontinuous linear shapes, or the entire surface of the N-layer light irradiation pattern is arbitrarily set. It is cured into a plurality of dots having a space of.

Next, as in the step (B-1), this N
By pulling up the laminate so that the cured layer as the second layer is exposed above the liquid surface of the photosensitive resin, the cured layer as the Nth layer and (N-1)
A step (hereinafter referred to as “step (B-3)”) of retaining the photosensitive resin liquid in a step portion between the cured layer and the cured layer is performed. When the laminate is pulled up so that the Nth cured layer is exposed above the liquid surface of the photosensitive resin, the photosensitive resin liquid is formed in the step portion between the Nth cured layer and the (N-1) th cured layer. Stays and fills the step to form a slope.

Subsequently, while the Nth cured layer was exposed on the surface of the photosensitive resin liquid, light was irradiated in accordance with the shape of the (N-1) th cured layer to stay in the step portion. The step of curing the photosensitive resin and the uncured photosensitive resin of the Nth layer (hereinafter referred to as “step (C-3)”) is performed. N
With the cured layer of the second layer exposed on the surface of the photosensitive resin, (N-
1) When light is irradiated along the shape of the cured layer of the first layer, the photosensitive resin staying in the step portion is cured to form a laminated body with few steps, and the uncured photosensitive resin of the Nth layer is cured. Then, the Nth cured layer is formed.

Then, similarly to the step (D-2), a step of lowering the laminated body to a position where the (N + 1) th layer is formed (hereinafter referred to as "step (D-3)") is performed. The step (A-
3), step (B-3), step (C-3) and step (D-3)
By repeating the process up to the final layer of the shape, a three-dimensional model can be formed.

Also by such a method, after the Nth hardened layer is formed, the Nth hardened layer is raised so that the uncured photosensitive resin remains at the peripheral portion of the Nth hardened layer. Then, since the uncured photosensitive resin is cured, it is possible to obtain the same effect as the above.

[0032]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to these examples.

[0033]

Example 1 According to the above-described method of the present invention, an evaluation model having inclined planes at intervals of 10 degrees in the range of 10 to 90 degrees with respect to the horizontal plane was formed under the following conditions.

That is, after irradiating the surface of a photosensitive resin liquid (SCR200, manufactured by Nippon Synthetic Rubber Co., Ltd.) with an ultraviolet laser beam to form an Nth cured layer, the Nth cured layer is exposed. The laminate by an elevator so that the laminate is exposed above the liquid surface of the resin (step (B-
1), (B-2) and (B-3), which correspond to the pulling conditions in the present invention in Table 1), and the Nth cured layer and the (N-1) th cured layer. The photosensitive resin liquid was allowed to stay in the step portion between and. After holding for a certain period of time (in Table 1, standing time for the amount of pulling up), ultraviolet laser light is irradiated according to the shape of the cured layer of the (N-1) th layer to cure the photosensitive resin liquid retained in the step portion. It was Next, the laminate is lowered by an elevator and held for a certain period of time to allow the photosensitive resin to wrap around the upper surface of the Nth cured layer, and then the laminate is pulled up to a position where the (N + 1) th layer is formed and held for a certain period of time. Then, an ultraviolet laser beam was irradiated to form a (N + 1) th cured layer. An evaluation model was formed by repeating the above steps. After modeling, the evaluation model was irradiated with a mercury lamp and post-cured for 2 hours.

[0035]

[Table 1]

The average surface roughness of each inclined surface of the evaluation model formed as described above is measured by a surface roughness meter (manufactured by Mitutoyo Co., Ltd.,
It was measured using Surfcom 300B).

[0037]

Comparative Example 1 An evaluation model as shown in FIG. 2 was formed under the following conditions according to the conventional method. That is, the surface of a photosensitive resin liquid (SCR200, manufactured by Nippon Synthetic Rubber Co., Ltd.) was irradiated with an ultraviolet laser beam to form an Nth cured layer. Next, the laminate is lowered by an elevator and held for a certain period of time to allow the photosensitive resin to wrap around the upper surface of the Nth cured layer, and then the laminate is pulled up to the position where the (N + 1) th layer is formed and held for a certain period of time. Then, an ultraviolet laser beam was irradiated to form a (N + 1) th cured layer. An evaluation model was formed by repeating the above steps.

[0038]

[Table 2]

The average surface roughness of each inclined surface of the evaluation model formed as described above was measured in the same manner as in Example 1.

The above results are shown in FIG. As shown in FIG. 3, according to the method of the present invention, the surface roughness is smaller than that of the conventional method, and the average surface roughness is 15 μm or less.

[0041]

Example 2 An evaluation model was formed in the same manner as in Example 1 except that the laminated thickness was 300 μm. The average surface roughness of each inclined surface of the obtained evaluation model was measured in the same manner as in Example 1.

[0042]

Comparative Example 2 An evaluation model was formed in the same manner as Comparative Example 1 except that the layer thickness was 300 μm. The average surface roughness of each inclined surface of the obtained evaluation model was measured in the same manner as in Example 1.

The above results are shown in FIG. Further, FIG. 5 shows cross-sectional curves of the inclined surface (broken line) of the evaluation model formed in Example 2 and the inclined surface (solid line) of the evaluation model formed in Comparative Example 2. As shown in FIG. 4, according to the method of the present invention, the surface roughness is smaller than that of the conventional method, and particularly in the inclined surface of 30 degrees or less, the average surface roughness is 15 μm or less in all cases. Further, as shown in FIG. 5, according to the method of the present invention, the step is small and the surface roughness is small especially when the inclination angle is small.

[0044]

According to the stereolithography method of the present invention, it is possible to fabricate a laminate having a surface roughness smaller than that of the conventional stereolithography method, and a laminate having a small surface roughness even if the lamination thickness is increased. Can be shaped. Therefore, it is not necessary to carry out secondary processing such as removing the steps of the laminated body, and a model having a desired shape can be obtained at low cost and in a short time.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a manufacturing process of a stereolithography method according to the present invention.

FIG. 2 is a schematic perspective view of an evaluation model manufactured in an example.

FIG. 3 is an evaluation model formed in Example 1 and Comparative Example 1
It is the figure which showed the surface roughness of the slope of the evaluation model modeled by.

FIG. 4 is an evaluation model formed in Example 2 and Comparative Example 2
It is the figure which showed the surface roughness of the slope of the evaluation model modeled by.

FIG. 5: Evaluation model formed in Example 2 and Comparative Example 2
It is a comparison figure of the section curve of the evaluation model modeled by. In the figure, the broken line is the sectional curve of the evaluation model formed in Example 2, and the solid line is the sectional curve of the evaluation model formed in Comparative Example 2.

[Explanation of symbols]

 10 ... Laminate 1 ... Photosensitive resin liquid 2 ... Elevator 3 ... Base plate 4 ... Retaining photosensitive resin liquid 5 ... Light

Claims (1)

[Claims] 1. An optical molding method for forming a cured layer by irradiating a surface of a photosensitive resin liquid with light, and laminating a plurality of the cured layers to form a laminate having a desired three-dimensional shape.
-1) A step of irradiating the photosensitive resin with light to form an Nth cured layer, (B-1) forming a laminate so that the Nth cured layer appears on the liquid surface of the photosensitive resin. A step of allowing the photosensitive resin liquid to stay in the step portion between the N-th cured layer and the (N-1) -th cured layer by pulling up, (C-1) the N-th cured layer is a photosensitive resin A step of curing the photosensitive resin liquid retained in the step portion while being exposed on the liquid surface, and a step of lowering the (D-1) laminated body to a position where the (N + 1) th layer is formed. Stereolithography method.