JP2001088424A - Foaming sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foaming sheet for forming a half stereoscopic image simply and accurately reproduced in a rugged shape of a stereoscopic material to be copied. SOLUTION: The foaming sheet SH10 is sequentially coated with foamable materials FB1, FB2, FB3 and FB4 from below on one surface of a sheet-like base material BP so as to specify a foaming direction. The materials FB1 to FB4 are constituted to foam the nearer material BP, that is, the material at a lower temperature farther from a heat source. In this case, the material FB1 foamed at a lowest temperature is arranged directly on a base material BP, and the material FB4 foaming at the highest temperature is arranged on the uppermost surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foam sheet for forming a three-dimensional modeled object such as a relief image by foaming.

[0002]

2. Description of the Related Art A desired image is formed by shading a highly light-absorbing material on a foaming material, and the entire image is irradiated with light, and the image is selectively heated and foamed by the difference in light absorption. hand,
Raised images (semi-stereoscopic images) with different heights depending on the contrast of the image
Has been proposed by Yoshimichi Yonezawa (Japanese Patent Publication No. 59-35359).

Further, the toner is transferred to a foaming material,
A three-dimensional copying machine (Minolta Co., Ltd.) that obtains three-dimensional characters and braille by heating, or a thermally expandable thermal transfer sheet is selectively thermally expanded, and the expanded layer is transferred onto a transfer-receiving sheet. An apparatus for obtaining a semi-stereoscopic image by further heating and foaming is known (Japanese Patent Laid-Open No. Hei 10-138339).

[0004] A semi-stereoscopic image is an image that reproduces unevenness when a three-dimensional object is viewed from one direction, and is not a reproduction of the entire three-dimensional object. In addition,
It is sometimes called a 2.5-dimensional image.

[0005]

Although these devices are suitable for copying a two-dimensional image such as a character or a line drawing as a half-stereoscopic image, the object to be copied is a three-dimensional object, and It is difficult to create a semi-stereoscopic image reflecting irregularities, for example, a frontal stereoscopic image of a human face.

In the Yonezawa method, it is possible to obtain semi-stereoscopic images having different heights depending on the shading of the image. However, it is difficult to accurately reproduce complicated unevenness of a three-dimensional object only by shading of the light absorbing material. there were.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and a foam sheet for forming a semi-stereoscopic image which simply and accurately reproduces the uneven shape of a three-dimensional object to be copied. The purpose is to provide.

[0008]

The foamed sheet according to the present invention is a foamed sheet which foams by being heated based on information of a three-dimensional object and forms a semi-stereoscopic image of the three-dimensional object. In addition, the foam sheet includes a plurality of foam materials having different foaming temperatures, and the plurality of foam materials are stacked.

The foamed sheet according to claim 2 of the present invention, wherein the foamed sheet further comprises a sheet-shaped non-foamed base material, and the plurality of foamable materials have a foaming temperature in order from the base material side. It is laminated on the base material so as to be higher.

The foamed sheet according to claim 3 of the present invention, wherein the foamed sheet further comprises a sheet-shaped non-foamed base material, and the plurality of foamable materials have a foaming temperature in order from the base material side. It is laminated on the base material so as to be lower.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Structure and operation of foam molding apparatus> Prior to description of an embodiment of a foam sheet according to the present invention, a foam molding apparatus for foaming a foam sheet to form a semi-stereoscopic image is described. The configuration and operation will be described.

<Example 1 of Apparatus Configuration> FIG. 1 shows the configuration of an foam molding apparatus 100 as an example of a foam molding apparatus. In FIG. 1, a foam molding apparatus 100 includes a foaming unit FM and a computer that realizes computer-aided design (CAD), computer graphics (CG), or the like.
A shape information creating unit 20 including a dimension measuring device, a data processing unit 30 that converts the shape information created by the shape information creating unit 20 into control data such as foam control data, and a data processing unit 30 that creates the shape information. The control unit 40 controls the foaming unit FM based on the generated foaming control data, controls the energy for foaming given from the foaming unit FM to the foamable material FB, and controls the foaming amount of the foamable material FB. .

<Expandable Material> Expandable material FB shown in FIG.
Conventionally, a heat-foamable material that foams by heat has been used. The thermofoamable material is composed of microcapsules in which low-boiling hydrocarbons are sealed in a microsphere shell made of a thermoplastic resin and a binder.

The microsphere shell has a particle size of 10 to 30 μm. As the shell wall material, for example, vinylidene chloride, acrylonitrile or the like is used, and as the low boiling point hydrocarbon, propane, butane, pentane or the like is used. . As the binder, a thermoplastic vinyl acetate polymer, an acrylic polymer, or the like is used.

<Foaming Unit> The foaming unit FM shown in FIG. 1 is a heating means for heating the foamable material FB, and appropriately gives heat to the foamable material FB under the control of the control unit 40. As a practical configuration of the foaming unit FM, heating by a laser beam is effective from the viewpoint of controlling the amount of heat and controlling the size of the foaming point to improve the resolution of a semi-stereoscopic image.

FIG. 2 shows a foaming unit F using a laser beam.
3 shows the configuration of M1. In FIG. 2, the foaming unit FM1
Is a laser light source LD and an optical system O that converges the laser light emitted from the laser light source LD and guides the laser light to a predetermined position.
P.

By using a semiconductor laser as the laser light source LD, the apparatus can be miniaturized. The wavelength of the laser light is set to a wavelength close to the infrared light, so that heat is efficiently generated when the foamable material FB is irradiated. Can be done.

<Apparatus Operation> Next, the operation of the foam molding apparatus 100 will be described with reference to the flowchart shown in FIG.

First, the shape information creating unit 20 creates shape information of a three-dimensional object to be copied (step S).
1). This is created based on shape data of a three-dimensional object created by using a computer or given to a computer, or measured by a three-dimensional measuring device or the like.

The shape information created by the shape information creating unit 20 is input to the data processing unit 30 (step S2), and the shape information is converted into foam control data (step S3). The foam control data is stored in the foam unit F on the foam material FB.
The data includes a scanning path (scanning path) for scanning M, a scanning speed, and the amount of heat to be supplied to each foaming portion and the heating temperature according to the foaming height of each foaming portion.

Next, a predetermined position of the expandable material FB set by the control unit 40 based on the expansion control data is heated and expanded by the expansion unit FM (step S).
4). Since this heating is performed based on data on the height of the foamed portion and the amount of heat input, the amount of heat input is different if the foaming height is different.

Then, the control unit 40 checks whether or not the set amount of heat has been applied to the foaming portion at a predetermined position (step S5). If the set amount of heat has not been applied, the operation of step S4 is performed. Repeatedly, when the set amount of heat is given, it is confirmed whether or not the foaming of all the foamed portions is completed (step S6), and when the foaming is completed, the heating operation is ended and the foaming is completed. If not, the operation from step S4 is repeated.

The operation in step S4 may be such that heating is continuously performed on one foamed portion until the set amount of heat is reached. However, heating of one foamed portion is performed until a certain amount of heat is reached. After that, the operation of moving the foaming unit FM to another foaming portion and heating the same is repeated, and while scanning over all the foaming portions a plurality of times, the heat quantity set in each foaming portion is finally input. As described above, the respective foamed portions may be heated in a cumulative manner.

FIG. 4 shows a conceptual diagram when a semi-stereoscopic image is formed on a foamable material. In FIG. 4, the foamable material F
A quadrangular pyramid-shaped foamed portion FP is formed on B. As described above, by controlling the foaming amount, the foamed portion FP having an arbitrary shape is formed.
Can be formed.

As described above, the foam molding apparatus 100
In, the amount of foaming, that is, the height of foaming is controlled by controlling the amount of heat applied to the foamable material by the foaming control data created based on the shape information of the three-dimensional object to be copied. Easy as a semi-stereoscopic image,
And can be accurately reproduced.

<Example of Apparatus Configuration 2> As an example of the foam molding apparatus, FIG. In FIG. 5, the foam molding apparatus 200 includes the foaming unit FM, the shape information creating unit 20, the data processing unit 30, and the control unit 40 shown in FIG. (Foaming height) is provided.

<Expansion Amount Measuring Unit> The foaming amount measuring unit FD moves in association with the foaming unit FM, measures the foaming amount (expansion height) of the foaming section formed by the foaming unit FM, and outputs the result to the control unit. It has a function to feed back to 40. The control unit 40 controls the foaming unit FM based on the information on the foaming amount, and controls the amount of heat applied to the foaming unit.

FIG. 6 is a conceptual diagram showing a state in which the foaming amount measuring unit FD measures the foaming height of the foaming portion FP formed by the foaming unit FM.

As an example of the operation of the foaming amount measuring unit FD, a foaming portion is foamed by applying a predetermined amount of heat in the state shown in FIG. 5, and then the foaming unit FM and the foaming amount measuring unit FD are relatively moved. Move to foaming amount measurement unit FD
To the foaming part FP. This state is shown in FIG. In the state shown in FIG. 6, the height of the foamed portion FP is measured, and if the height has reached a desired height, foaming of this portion is finished, and the process moves to the next foamed portion. When the height has not reached the desired height, the state returns to the state shown in FIG. 5 and the calorie is further applied from the foaming unit FM. Thus, the foaming and the measurement are repeated until the foamed portion reaches a desired height.

It should be noted that the foaming amount measuring unit FD and the foaming unit FM are arranged close to each other, and if the foaming position and the measuring position are substantially matched, foaming can be performed while measuring the foaming amount in real time. In this case, it is possible to shorten the time spent for controlling the amount of foaming and to manufacture the foamed molded article in a short time. The operation in this case will be described later with reference to FIG.

As a practical configuration of the foaming amount measuring unit FD, measurement using a laser beam is effective from the viewpoint of non-contact measurement and high measurement accuracy.

FIG. 7 shows the configuration of a foaming amount measuring unit FD1 using a laser beam. In FIG. 7, a foaming amount measuring unit FD1 includes a laser light source LD1 and a laser light source L.
An optical system OP1 that converges the laser light emitted from D1 and guides the laser light to a predetermined position, and a position sensor P disposed such that the optical axis of the laser light forms an angle with the optical axis of the laser light.
S.

The position sensor PS includes an optical system and a semiconductor position detector (PSD: Semiconducducer) arranged on the optical axis of the optical system.
torsion sensitive device), and the reflected light of the laser spot irradiated on the foamable material FB is formed into an image on the optical system.

When the distance from the laser light source LD1 to the laser spot changes due to the expansion of the expandable material FB, the amount of change is detected as the amount of change on the PSD. Can be known. This method is a method called optical triangulation.

As another configuration of the foaming amount measuring unit using laser light, there is a configuration using a focusing sensor.

FIG. 8 shows the configuration of a foaming amount measuring unit FD2 using a laser beam. In FIG. 8, a foaming amount measuring unit FD2 includes a laser light source LD1 and a laser light source L.
An optical system OP2 for converging and guiding a laser beam emitted from D1 to a predetermined position, a half mirror HM disposed on an optical axis in the optical system OP2, and an optical axis of light reflected by the half mirror HM. And a focusing sensor FS disposed at

The focusing sensor FS includes a separator lens disposed on the optical axis and a CC disposed thereafter.
D (Charge Coupled Device).

The reflected light of the laser spot irradiated on the foaming material FB is reflected by the half mirror HM toward the focusing sensor FS, is divided by the separator lens, and forms an image on the CCD. The interval between the divided spot images changes when the position of the laser spot changes in the optical axis direction. By detecting the amount of change, the distance to the laser spot, that is, the foaming height can be known.

<Apparatus Operation> Next, the operation of the foam molding apparatus 200 will be described with reference to the flowchart shown in FIG.

First, the control unit 40 controls the foaming unit FM to heat a predetermined position of the foamable material FB set based on the shape information of the three-dimensional object to be copied created by the shape information creating unit 20. , Foam (Step S
10).

The shape information created by the shape information creating unit 20 is input to the data processing unit 30 and is sent to the foaming unit FM.
Is converted into scanning control data including a scanning path (scanning path), a scanning speed, and a foam height, and is provided to the control unit 40.

Next, the foaming amount (foaming height) of the foaming portion is measured by the foaming amount measuring unit FD while heating and foaming in the foaming unit FM (step S11). The measurement result is provided to the control unit 40, and is compared with a set height set for each foamed portion to check whether the foamed height of the foamed portion at a predetermined position has reached the set height ( Step S12) If the height has not reached the set height, heating is performed again to perform measurement, and if the height has reached the set height, the heating operation on the foamed portion is terminated. The amount of heat given from the foaming unit FM to the foamable material FB is, for example, per unit time.
Can be reduced to the minimum foaming level, and a heating operation in which heating in a unit time and height measurement are repeated can be adopted.

Subsequently, it is confirmed whether or not the foaming of all the foamed portions set by the scanning control data has been completed (step S13). If the foaming has been completed, the heating operation is terminated, and the foaming is completed. If not, it is moved to the next predetermined position, and the operation after step S10 is repeated.

In the operation of step S10, heating may be continuously repeated until one foamed portion reaches a set height. However, heating is performed until one foamed portion reaches a certain height. After that, the operation of moving the foaming unit FM to another foaming part and heating it is repeated, and while scanning all foaming parts a plurality of times, finally each foaming part is set to the respective set height. For example, the respective foamed portions may be heated in a cumulative manner.

As described above, in the foam molding apparatus 200 according to the second embodiment of the present invention, the foaming height is measured by the foaming amount measuring unit FD in the process of forming the foamed portion, and each foamed portion is set in advance. Since the control is performed so that the set height is set, the shape of the three-dimensional object can be easily formed as a half-stereo image,
It can be reproduced more accurately.

Here, a state in which the foamable material FB used in the foam molding apparatuses 100 and 200 described with reference to FIGS. 1 and 2 is foamed will be described with reference to FIGS. 10 and 11.

FIG. 10 is a schematic diagram showing the state of heat diffusion when the foaming material FB having a substantially uniform thermal diffusivity over the entire area is heated by the foaming unit FM. (Temperature region) HR is indicated by hatching.

When the foamable material FB is to be foamed at a high level, it is necessary to heat the heating region so as to reach a deep position of the foamable material FB. If the thermal diffusivity is uniform, the heat spreads radially around the heat source (that is, the foaming unit FM) as shown in FIG. 10, so that if the portion remote from the heat source is foamed, the heat spreads. Accordingly, the foamed portion expands, and it becomes difficult to accurately reproduce the fine shape of the three-dimensional object to be copied. FIG. 11 shows a state in which the foamable material FB has foamed.

The present invention uses a foamed sheet in which a plurality of foamable materials having different foaming temperatures are laminated, thereby preventing the expansion of the foamed portion due to the spread of heat and accurately determining the three-dimensional object to be copied. It is based on the technical idea of reproducing in the same way. Hereinafter, embodiments for realizing the technical idea will be described.

<A. First Embodiment><A-1. Structure of Foam Sheet> FIG. 12 is a view showing the structure of the foam sheet SH10 according to the first embodiment of the present invention. In FIG. 12, the foamed sheet SH10 has foamable materials FB1, FB2, FB3, and FB on one surface of a sheet-like substrate BP in order from the bottom so as to regulate the direction of foaming.
4 are coated.

The foamable materials FB1 to FB4 are configured so that the foaming temperature increases in order from the base material BP side, in other words, the foamable material which is farther from the heat source foams at a lower temperature. The FB1 is disposed immediately above the base material BP, and the foamable material FB4 that foams at the highest temperature is disposed on the outermost surface.

The foam sheet SH10 having such a structure is as follows.
As shown in FIG. 12, the foaming material FB4 is heated and foamed by the foaming unit FM from the foaming material FB4 side. In FIG. 12, the foaming temperature regions HR1 to HR4 in the foaming materials FB1 to FB4 are hatched. Is shown.

As shown in FIG. 12, the foaming temperature of the foamable material FB4 should be set so as to foam at the deepest temperature of the foamable material FB4 in the heat distribution spreading radially around the foaming unit FM. Thus, the foaming temperature region HR4 is only the region immediately below the foaming unit FM, and the other regions do not reach the foaming temperature. In other words, among contour lines formed by heat distribution spreading radially around the foaming unit FM, this is a region surrounded by contour lines indicating the temperature at the deepest part of the foamable material FB4.

The foaming material FB3 is made of a foaming unit F
By setting the foaming temperature so that the foaming material foams at the deepest temperature of the foamable material FB3 in the heat distribution radially spreading around M, the foaming temperature region HR3 is expanded by the foaming unit FM.
Is a region surrounded by contour lines indicating the temperature at the deepest part of the expandable material FB3 among the contour lines formed by the heat distribution radiating from the center.

The same applies to the foamable materials FB2 and FB1, and the foaming temperature is set so that foaming is performed at the deepest temperature of the foamable materials FB2 and FB1 in the heat distribution spreading radially around the foaming unit FM. Thus, the foaming temperature regions HR2 and HR1 are among contour lines formed by a heat distribution that spreads radially around the foaming unit FM.
This is a region surrounded by contour lines indicating the temperatures at the deepest portions of the foamable materials FB2 and FB1.

The foaming temperature of the foamable materials FB1 to FB4 may be set so as to change the foaming temperature in increments of, for example, 10 ° C., such as 70 ° C., 80 ° C., 90 ° C., and 100 ° C.

As described above, foamable materials F having different foaming temperatures are used.
FIG. 13 shows an image of the shape of the foamed portion FP1 when the foamed sheet SH10 in which B1 to FB4 are laminated is foamed. As shown in FIG. 13, the foamed portion FP1 has a smaller spread in the planar direction than the foamed portion FP of the foamable material FB shown in FIG. 11, and the ratio of the foaming height to the spread in the planar direction is higher.

<A-2. Configuration of Foamable Material> Here, a configuration for changing the foaming temperature of the foamable material will be described. As described above, the foamable material includes microcapsules in which low-boiling hydrocarbons are encapsulated as an expanding substance inside a microsphere shell made of a thermoplastic resin. The low-boiling hydrocarbon inside expands, and the shell wall expands and expands due to an increase in the internal pressure, whereby the foamable material enters a foaming state.

Here, the structure of the microcapsule is shown in FIG.
Shown in As shown in FIG. 14, the microcapsule MC has a spherical shell shape, and an inflating substance EP is contained inside a shell wall SW.
Is enclosed.

In such a thermoplastic microcapsule, it is set so that expansion occurs rapidly at a predetermined temperature, that is, at a foaming temperature. The foaming temperature is set according to the strength of the shell wall and the expansion characteristics.

Therefore, the foaming temperature of the foamable material can be arbitrarily changed by changing the strength and expansion characteristics of the shell wall.

The strength of the shell wall can be changed by changing the thickness of the shell wall and the material of the shell wall. For example, in the case of the foam sheet SH10 shown in FIG. What is necessary is just to comprise it from the microcapsule of the material with a small strength of a shell wall.

The expansion characteristics can be changed by changing the amount of the expansion substance sealed in the microcapsules. That is, a microcapsule with a larger amount of the expanding substance can reach the foaming temperature at a lower temperature than a microcapsule with a smaller amount of the expanding material. Therefore, taking the foamed sheet SH10 shown in FIG. 12 as an example, the foamable material farther from the heat source may be constituted by microcapsules in which more expandable substance is sealed.

Of course, the setting of the foaming temperature may be changed depending on the combination of the strength and expansion characteristics of the shell wall, or a foaming material having a different foaming amount with respect to the foaming temperature depending on the combination of the strength and expansion characteristics of the shell wall. It can also be configured.

The foaming materials having different foaming temperatures are sold by Dainippon Ink and Chemicals, Inc., one of the suppliers of foaming materials. , A foaming temperature of about 150 ° C and a foaming temperature of about 180 ° C.

As the base material BP, for example, paper or a resin sheet such as PET (polyethylene terephthalate) can be used. These materials are generally low in thermal diffusivity, are materials suitable for preventing diffusion of heat and foaming only necessary portions.

<A-3. Operation and Effect> As described above, the foamed sheet SH10 according to the first embodiment of the present invention.
Is formed by sequentially laminating foamable materials FB1 to FB4 having different foaming temperatures on the base material BP so that the farther from the heat source foams at a lower temperature, the uppermost foamable material F
When the foamed sheet SH10 is heated from the B4 side, the expansion of the foaming portion in the planar direction is small, and the ratio of the foaming height to the planar expansion is increased, thereby accurately reproducing the uneven shape of the three-dimensional object to be copied. Can be.

<B. Second Embodiment><B-1. Configuration of Foam Sheet> The foam sheet SH10 according to the first embodiment described above is for heating and foaming from the uppermost foamable material FB4 side by the foaming unit FM as shown in FIG. Since the direction of foaming is regulated in the direction opposite to the direction of the base material BP due to the presence of the base material BP, the foaming unit FM can be disposed on the base material BP side and heated. When this configuration is adopted, the order of coating the foamable material is opposite to that of the foam sheet SH10.

FIG. 15 is a view showing the structure of the foam sheet SH20 according to the second embodiment of the present invention. In FIG. 15, a foam sheet SH20 is formed by coating a foam material FB4, FB3, FB2, and FB1 on one surface of a sheet-like base material BP for regulating the direction of foaming in order from the bottom.

The foamable materials FB1 to FB4 are configured so that the foaming temperature becomes lower in order from the base material BP side, in other words, the farther away from the heat source, the lower the temperature of the foamable material. FB1 is disposed on the uppermost layer, and the foamable material FB4 that is foamed at the highest temperature is disposed immediately above the base material BP.

The foam sheet SH20 having such a structure is as follows.
As shown in FIG. 15, foaming is performed by heating from the base material BP side by the foaming unit FM. In FIG. 15, the foaming temperature regions HR1 to HR4 in each of the foamable materials FB1 to FB4 are hatched. Is shown.

As shown in FIG. 15, the foamable material FB4
Is the deepest part (foaming unit F) of the foaming material FB4 in the heat distribution radiating around the foaming unit FM.
By setting the foaming temperature so as to foam at the temperature of the part farthest from M), the foaming temperature region HR4 is a foamable material among contour lines formed by a heat distribution that spreads radially around the foaming unit FM. This is a region surrounded by contour lines indicating the temperature at the deepest part of FB4.

Further, the foaming material FB3 is a foaming unit F
By setting the foaming temperature so that the foaming material foams at the deepest temperature of the foamable material FB3 in the heat distribution radially spreading around M, the foaming temperature region HR3 is expanded by the foaming unit FM.
Is a region surrounded by contour lines indicating the temperature at the deepest part of the expandable material FB3 among the contour lines formed by the heat distribution radiating from the center.

The same applies to the foamable materials FB2 and FB1, and the foaming temperature is set so that foaming is performed at the deepest temperature of the foamable materials FB2 and FB1 in the heat distribution spreading radially around the foaming unit FM. Thus, the foaming temperature regions HR2 and HR1 are among contour lines formed by a heat distribution that spreads radially around the foaming unit FM.
This is a region surrounded by contour lines indicating the temperatures at the deepest portions of the foamable materials FB2 and FB1.

The foamable materials F having different foaming temperatures as described above
FIG. 16 shows an image of the shape of the foamed portion FP2 when the foamed sheet SH20 in which B4 to FB1 are laminated is foamed. As shown in FIG. 16, the foamed portion FP2 has a smaller spread in the planar direction than the foamed portion FP of the foamable material FB shown in FIG. 11, and the ratio of the foaming height to the spread in the planar direction is higher.

<B-2. Action and Effect> As described above, the foam sheet SH20 according to the second embodiment of the present invention.
Is formed by sequentially laminating the foamable materials FB4 to FB1 having different foaming temperatures on the base material BP so that the material farther from the heat source foams at a lower temperature, so that when the foamed sheet SH20 is heated from the base material BP side, In addition, the expansion of the foamed portion in the plane direction is small, and the ratio of the foaming height to the expansion in the plane direction is increased, so that the uneven shape of the three-dimensional object to be copied can be accurately reproduced.

<B-3. Modification> The foam sheet SH20 of the second embodiment described above and the foam sheet SH10 of the first embodiment described with reference to FIG. 12 are formed by coating the base material BP with the foamable materials FB1 to FB4. Although the configuration has been described, a configuration in which only the foamable materials having different foaming temperatures are laminated and coated without using the base material BP may be used.

That is, the foam sheet SH3 shown in FIG.
0, foamable material FB5, FB in order from the heating side
6, FB7 and FB8 are laminated by coating.

The foamable materials FB5 to FB8 are configured to foam at a lower temperature as they are farther from the heat source, and the foamable material FB5 that foams at the highest temperature is disposed so as to be closest to the heating side. The foaming material FB8 to be foamed is disposed so as to be farthest from the heating side.

In FIG. 17, foamable materials FB5 to FB
The foaming temperature regions HR5 to HR8 in each of B8 are indicated by hatching.

As shown in FIG. 17, the foamable material FB5
Is the deepest part of the foamable material FB5 (foaming unit F) among the heat distribution radially spreading around the foaming unit FM.
By setting the foaming temperature so as to foam at the temperature of the part farthest from M), the foaming temperature region HR5 is one of the contour lines formed by the heat distribution spreading radially around the foaming unit FM. This is a region surrounded by contour lines indicating the temperature at the deepest part of FB5.

The foaming material FB6 is made of a foaming unit F
By setting the foaming temperature so that the foaming material foams at the deepest temperature of the foamable material FB6 in the heat distribution radiating radially around M, the foaming temperature region HR6 becomes the foaming unit FM.
Is a region surrounded by contour lines indicating the temperature at the deepest part of the expandable material FB3 among the contour lines formed by the heat distribution radiating from the center.

The foaming materials FB7 and FB8 are the same, and the foaming temperature is set so that the foaming material FB7 and FB8 foam at the deepest temperature in the heat distribution spreading radially around the foaming unit FM. Thus, the foaming temperature regions HR7 and HR8 are among contour lines formed by a heat distribution radiating radially from the foaming unit FM.
This is a region surrounded by contour lines indicating the temperatures at the deepest portions of the foamable materials FB2 and FB1.

The foam sheets SH10 to SH10 described above
In SH30, the thickness of each foamable material has not been mentioned, but the thickness of each foamable material may be different or the same.

As described above, the expandable material is composed of the microcapsules enclosing the expandable substance and the binder, and is generally supplied in a liquid state. Therefore, when forming the foamed sheet, the coating thickness of the foamable material can be arbitrarily changed.

Further, by setting the overall thickness of the foamed sheets SH10 to SH30 to about 5 mm at the maximum, a three-dimensional effect of the uneven shape of the three-dimensional object can be obtained.

Further, Embodiments 1 and 2 described above
In the above, a configuration using a laser beam as an energy source for foaming was shown, but it is not limited to a laser beam as long as the energy required for foaming can be locally concentrated, and visible light, infrared light, ultraviolet The light may be converged, or an energy source other than light may be used.

[0088]

According to the foamed sheet according to claim 1 of the present invention, since a plurality of foamable materials are laminated in the order of the foaming temperature, by heating from the foamable material having a high foaming temperature, Foaming of the foaming material close to the heat source is suppressed, and foaming of the foaming material far from the heat source is promoted. Of the three-dimensional object to be copied can be accurately reproduced.

According to the foamed sheet according to the second aspect of the present invention, since a plurality of foamable materials are laminated so that the foaming temperature increases in order from the substrate side, heating is performed from the side opposite to the substrate. In this case, the expansion of the foamed portion in the plane direction is small, and the ratio of the foaming height to the expansion in the plane direction is increased, so that the uneven shape of the three-dimensional object to be copied can be accurately reproduced.

According to the foamed sheet according to the third aspect of the present invention, since a plurality of foamable materials are laminated so that the foaming temperature becomes higher in order from the substrate side, when heating is performed from the substrate side. In addition, the expansion of the foamed portion in the plane direction is small, and the ratio of the foaming height to the expansion in the plane direction is increased, so that the uneven shape of the three-dimensional object to be copied can be accurately reproduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a foam molding apparatus using a foam sheet according to the present invention.

FIG. 2 is a diagram showing a configuration of a foaming unit using laser light.

FIG. 3 is a flowchart illustrating the operation of the foam molding apparatus.

FIG. 4 is a conceptual diagram of a semi-stereoscopic image formed on a foamable material.

FIG. 5 is a diagram illustrating a configuration of a foam molding apparatus using the foam sheet according to the present invention.

FIG. 6 is a diagram illustrating a configuration of a foam molding apparatus using the foam sheet according to the present invention.

FIG. 7 is a diagram showing a configuration of a foaming amount measuring unit using laser light.

FIG. 8 is a diagram showing a configuration of a foaming amount measuring unit using a laser beam.

FIG. 9 is a flowchart illustrating the operation of the foam molding apparatus.

FIG. 10 is a schematic diagram showing a heat diffusion state when heating a single-layer foamable material.

FIG. 11 is a schematic diagram showing a foamed state of a single-layer foamable material.

FIG. 12 is a schematic diagram showing a heat diffusion state when heating a multi-layered foamable material having a base material.

FIG. 13 is a schematic view showing a foamed state of a multilayer foamable material having a base material.

FIG. 14 is a partial cross-sectional view illustrating a configuration of a microcapsule included in a foamable material.

FIG. 15 is a schematic diagram showing a heat diffusion state when heating a multi-layer foamable material having a base material.

FIG. 16 is a schematic diagram showing a foamed state of a multilayer foamable material having a base material.

FIG. 17 is a schematic view showing a foamed state of a multilayer foamable material having no base material.

[Explanation of symbols]

 FB1 to FB8 Foamable material, BP substrate

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H111 HA12 HA14 HA23 HA24 HA35 2H113 AA06 BA27 BB08 BC03 BC10 CA13 CA46 DA22 DA50 DA53 DA57 FA10 FA29 4F100 AT00C BA03 BA07 BA25 CA01A CA01H EJ02 GB71 JA01B JD04 JD04A JD04B

Claims (3)

[Claims] 1. A foam sheet that is foamed by being heated based on information of a three-dimensional object and forms a semi-three-dimensional image of the three-dimensional object, wherein the foam sheet includes a plurality of foamable materials having different foaming temperatures. A foamed sheet, comprising: the plurality of foamable materials being laminated. 2. The foamed sheet further includes a sheet-shaped non-foamed base material, and the plurality of foamable materials are laminated on the base material such that a foaming temperature increases in order from the base material side. The foamed sheet according to claim 1, wherein 3. The foamed sheet further includes a sheet-shaped non-foamed base material, and the plurality of foamable materials are laminated on the base material such that a foaming temperature becomes lower in order from the base material side. The foamed sheet according to claim 1, wherein