JP2004283871A - Method for manufacturing plastic structural body having micropore part and plastic structural body having micropore part made by the same method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of plastic structural body having micropore parts by which the pore parts having fine diameter are easily formed on plastics. <P>SOLUTION: This manufacturing method of the plastic structural body having the micropore parts is a manufacturing method of the plastic structural body having a through holes and/or a depressed holes the smallest diameter or width of which is ≤ 200μm as a pore part. The pore part is formed by laser beam machining utilizing multiple photon absorbing process. As a plastic base material before the pore parts are formed, a plastic sheet or film is suitable. As the plastic structural body having the micropore parts, the plastic structural body having the micropore parts has the through hole and may have a filter function, membrane function, separator function, atomizing function, gas diffusing function, nozzle function, or flow-passage adjusting function. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a plastic structure having micropores and a plastic structure having micropores produced by the production method.
[0002]
[Prior art]
In recent years, there has been an increasing demand for higher performance and higher performance of plastic parts. In response to these requirements, two approaches have been taken: technical support on the material side, where the plastic material itself is polymer alloyed or composited, and technical support on the processing side, where functional parts are added in accordance with the required functions. ing. High-functionality and high-performance of the surface of plastic parts are achieved by surface wettability, adhesiveness, adsorptivity, antistatic property, barrier property against moisture and gas, surface hardness, light reflectivity, light scattering property, light transmission Various technical efforts have been made from both the material and processing side due to the necessity of control of properties. For example, when functions such as a filter, a membrane, and a separator are added to a plastic part by forming micropores, methods such as stretching, extraction, and phase separation are mainly used.
[0003]
On the other hand, technological progress related to laser light sources is remarkable. ^-9 ) Seconds to pico (10 ^-12 ) Seconds and ultra-short pulses, and more recently, femto (10 ^-15 ) Second pulse lasers have been developed. Ultrashort pulse laser systems such as picoseconds and femtoseconds, in addition to the characteristics of ordinary lasers, such as directivity, spatial and temporal coherence, etc., have a very narrow pulse width, and even at the same average output, unit time / unit Since the electric field strength per space is extremely high, attempts to form an induced structure by irradiating a substance and utilizing the high electric field strength have been carried out mainly using inorganic glass materials.
[0004]
Conventionally, there has been proposed a method in which a film made of a polymer material (polyethylene terephthalate or the like) is irradiated with laser light to perform perforation processing (see Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-118569
[0006]
[Problems to be solved by the invention]
However, in the method for producing a filter for classifying fine particles using a laser described in JP-A-10-118569, the unique effect of an ultrashort pulse laser is not exhibited, and a plastic has a small diameter hole. A portion (particularly, a minute hole composed of a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less) cannot be formed.
[0007]
Accordingly, an object of the present invention is to provide a method for producing a plastic structure having micropores that can easily form a microdiameter hole in plastic, and a plastic structure having micropores by the production method. There is to do.
Another object of the present invention is to provide a method for producing a plastic structure having a microhole portion that does not require a mask and that can form a microscopic through hole and / or a recessed hole with excellent productivity, and An object of the present invention is to provide a plastic structure having micropores by the manufacturing method.
[0008]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the inventors of the present invention have a pulse width of 10 on a plastic film. ^-9 It has been found that when a laser having an ultrashort pulse with a wavelength of less than a second and a wavelength of visible light is irradiated, multiphoton absorption occurs, so that precise micropores can be formed in the plastic film. The present invention has been completed based on these findings.
[0009]
That is, the present invention is a method of manufacturing a plastic structure having a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less as a hole, and the hole is utilized in a multiphoton absorption process. Provided is a method for producing a plastic structure having micropores, which is formed by laser processing.
[0010]
In the method for producing a plastic structure having micropores according to the present invention, a plastic sheet or film can be suitably used as the plastic substrate to be processed before forming the holes.
[0011]
As the plastic structure having a micropore, the plastic structure having a micropore has a through-hole and has a filter function, a membrane function, a separator function, an atomization function, a gas diffusion function, a nozzle function, or It preferably has a flow path adjustment function.
[0012]
For laser processing using the multiphoton absorption process, the pulse width is 10 ^-9 Laser processing using a laser with an ultrashort pulse of less than 1 second may be used, and the pulse width is 10 ^-9 The ultrashort pulse laser of less than a second may be an ultrashort pulse laser having a wavelength in the ultraviolet wavelength region to the near infrared wavelength region. Such a pulse width is 10 ^-9 Lasers with ultrashort pulses of less than a second can be irradiated with multi-beam interference. The pulse width is 10 ^-9 Irradiate a laser with an ultrashort pulse of less than a second while moving the focal point of the ultrashort pulse laser in a direction perpendicular to the direction of irradiation of the ultrashort pulse laser and in a direction parallel to the plastic surface. It is preferable.
[0013]
In addition, it is preferable that the plastic base material to be processed before forming the hole portion contains a fluorine resin or an olefin resin as a raw material, and may contain inorganic fine particles on the surface and / or inside thereof. .
[0014]
In addition, the present invention provides a plastic structure having a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less as a hole, wherein the hole has the micro hole. A plastic structure having micropores, characterized in that it is formed by the manufacturing method described above.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings as necessary. In addition, the same code | symbol may be attached | subjected to the same site | part or member.
(Plastic structure with micropores)
The plastic structure having a microscopic hole of the present invention is a plastic structure having a microscopic hole having a minimum diameter or width of 200 μm or less as the hole, and the hole utilizes a multiphoton absorption process. It is formed by laser processing. Such micropores (sometimes simply referred to as “holes”) include a through-hole having a shape penetrating from one surface to the other surface, and a recessed hole having a shape recessed from the surface to the inside. Any of these may be sufficient, and the through-hole and the depression hole may be combined. That is, the plastic structure having a microscopic hole can have a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less as the hole.
[0016]
As a plastic structure which has such a micropore part, the plastic structure which has a micro through-hole and a micro depression hole as shown in FIGS. 1-4 is mentioned, for example. 1 and 2 are schematic bird's-eye views each schematically showing an example of a plastic structure having a minute through hole. Specifically, FIG. 1A is a schematic bird's-eye view schematically showing an example of a plastic structure having a minute through hole, and FIG. 1B is an X diagram in FIG. ₁ -X ₁ It is sectional drawing in a 'line. Moreover, Fig.2 (a) is a schematic bird's-eye view which shows typically the other example of the plastic structure which has a micro through-hole, FIG.2 (b) is X in FIG.2 (a). ₂ -X ₂ It is sectional drawing in a 'line. 1 has a plurality of through holes 2a formed so as to penetrate from one surface of the plastic film 1 to the other surface. 2 has a plurality of through holes 2b formed so as to penetrate from one surface of the plastic film 1 to the other surface. Specifically, the through hole 2a has a cylindrical shape. The through-hole 2b has a shape in which a plurality of the cylindrical through-holes 2a are connected or a shape similar thereto. Accordingly, the through hole 2b is a through hole having a structure in which the minor axis (width) is minute but the major axis is not minute.
[0017]
Moreover, FIGS. 3-4 is a schematic bird's-eye view which shows typically the example of the plastic structure which has a micro depression hole, respectively. Specifically, FIG. 3A is a schematic bird's-eye view schematically showing an example of a plastic structure having a minute recessed hole, and FIG. 3B is an X-ray diagram in FIG. ₃ -X ₃ It is sectional drawing in a 'line. FIG. 4A is a schematic bird's-eye view schematically showing another example of a plastic structure having a minute recessed hole, and FIG. 4B is an X-ray diagram in FIG. ₄ -X ₄ It is sectional drawing in a 'line. 3 has a plurality of recessed holes (recesses) 2c formed on the surface of the plastic film 1 by being recessed from the surface of the plastic film 1. As shown in FIG. 4 has a plurality of depression holes (recesses) 2d formed by depression from the surface of the plastic film 1 to the inside. Specifically, the cross section of the recessed hole 2c can have a shape of a substantially semicircle, a substantially semi-ellipse, or a substantially triangle (in FIG. 3, it is illustrated as a substantially semi-circle or a substantially semi-ellipse) The recessed hole 2d has a shape that is cut by the recessed hole 2c having the cross-sectional shape or a shape similar to this. Therefore, the recessed hole 2d is a recessed hole having a structure (grooved structure) having a minor diameter (width) which is very small but not a minute diameter, and the sectional shape of the recessed hole 2d is the cross section of the recessed hole 2c. It can have the same shape as the shape (for example, a substantially semicircle, a substantially semi-ellipse, a substantially triangle, etc.).
[0018]
Thus, as a plastic structure having a minute hole portion, a through hole or a depressed hole (such as a “single hole portion”) in which the shape of the plastic surface is circular, such as the minute through hole 2a or the minute depressed hole 2c. A through-hole or depression (such as “connection”) having a shape in which the single holes are connected, or a shape similar to this, such as a plastic in which a single-hole portion is formed, a minute through-hole 2b, a minute depression 2d, or the like. A plastic in which a “hole” may be formed) may be formed.
[0019]
The diameter of the microhole portion (the micro through holes 2a and 2b and the micro recessed holes 2c and 2d) may be a minimum diameter or width of 200 μm or less, for example, 0.05 to 200 μm (preferably 0.05). ˜100 μm, more preferably 0.5 to 50 μm). When the micropore is a single hole, the diameter means a diameter (or average diameter), and when it is a connecting hole, the diameter means a width. Further, the diameter of the micropore portion means the diameter on the plastic surface (or the same surface as the surface).
[0020]
In addition, when the micropore has a shape having a major axis and a minor axis as in the case of the connecting hole, the minor axis may be 200 μm or less, and the major axis The length is not particularly limited. Specifically, the diameter of the micropores may be, for example, a minor axis of 0.05 to 200 μm and a major axis of 0.05 μm or more (for example, 0.05 to 100,000 μm). Moreover, as a preferable diameter of a micropore part, a minor axis is 0.05-100 micrometers, a major axis is 0.1 micrometer or more (for example, 0.1-5000 micrometers), Furthermore, a minor axis is 0.5- It is preferable that it is 50 micrometers and a major axis is 0.1-1000 micrometers.
[0021]
In particular, when the microhole portion is not penetrating (in the case of a microrecessed hole), even if the minor axis is 0.05 to 200 μm and the major axis is a slit groove-like recessed hole from end to end of the substrate, Good.
[0022]
In addition, when the microhole is a microrecessed hole (recessed part), the depth of the microrecessed hole is not particularly limited. However, the thickness of the processed plastic base material (plastic base material) before forming the hole is determined. For example, it can be selected from a range of 0.1 μm or more (for example, 0.1 to 10 μm, preferably 0.5 to 8 μm).
[0023]
In addition, the shape of the micropores on the surface of the plastic structure is not particularly limited and may be indefinite. For example, from a macro or overall viewpoint, a circularly similar shape (a circularly similar shape or The shape may be an ellipse-like shape) or a quadrangle-like shape (such as a square-like shape or a rectangular-like shape). Accordingly, the shape of the micropores on the surface of the plastic structure may be, for example, from a microscopic viewpoint, for example, the circumference of a circularly similar shape may be a curved shape such as a jagged shape, a wavy shape, or a saw shape. The long side of the similar shape may not be a straight line but may be a curved shape such as a jagged shape, a wavy shape, a saw shape, or a bent line shape.
[0024]
As a plastic structure which has a micropore part, it may have only one micropore part and may have multiple as shown in FIGS. In the case of having a plurality of micropores, it is preferable that the interval between adjacent pores is equal to or greater than the minimum diameter or width. The interval between adjacent holes may or may not be constant. The interval between adjacent holes means the distance between the centers of the circular shapes of the plastic surface when the holes are single holes, and the width of the plastic surface when the holes are connecting holes. It can mean the center-to-center distance in the direction.
[0025]
(Formation of plastic structure with micropores)
The plastic structure having a microscopic hole of the present invention can be formed by laser processing using a multiphoton absorption process. By utilizing the multiphoton absorption process, even if the wavelength of the laser beam to be used is longer than the absorption wavelength of the material (polymer component) of the processed plastic substrate before forming the hole, the processed plastic substrate The material can be processed to form micropores having a minimum diameter or width of 200 μm or less. In other words, fine processing can be performed efficiently and with excellent accuracy by laser processing using a multiphoton absorption process.
[0026]
Note that laser processing using a multiphoton absorption process uses a phenomenon in which a plurality of photons are simultaneously absorbed by a substance when a high-density photon is present, and cannot originally be generated with the energy of one photon. Means processing. In addition, since the processing uses a nonlinear phenomenon, processing exceeding the diffraction limit of the irradiation wavelength is possible despite the use of light.
[0027]
The laser processing method using such a multi-photon absorption process is not particularly limited as long as it is a method using a multi-photon absorption process when processing by irradiating a laser. 10 ^-9 A laser processing method using an ultrashort pulse laser (which may be referred to as “ultrashort pulse laser” or “laser”) of less than a second can be suitably employed. As such an ultrashort pulse laser, a pulse width obtained by reproducing and amplifying a laser using a titanium / sapphire crystal or a dye laser is 10. ^-9 The pulse width of a pulse laser, excimer laser, or YAG laser (Nd-YAG laser, etc.) of a subsecond is 10 ^-9 For example, a pulse laser of 10 seconds or less can be used, and in particular, a pulse width obtained by reproducing and amplifying a laser using a titanium / sapphire crystal or a dye laser is 10 ^-12 Seconds to 10 ^-15 A pulsed laser (femtosecond pulsed laser) on the order of femtoseconds in seconds can be suitably used. Of course, the pulse width in the ultrashort pulse laser is 10 ^-9 There are no particular restrictions as long as it is less than or equal to seconds, for example ^-9 10 seconds ^-12 Picosecond order of seconds and 10 ^-12 10 seconds ^-15 Femtosecond order of seconds (preferably 10 ^-12 10 seconds ^-15 Femtoseconds on the order of seconds) and typically 100 femtoseconds (10 ^-13 Second). The pulse width obtained by reproducing and amplifying a laser or dye laser using such a titanium / sapphire crystal as a medium is 10 ^-9 A pulse width of 10 seconds or less, a double wave of an excimer laser or a YAG laser (Nd-YAG laser, etc.) is 10 ^-9 When an ultrashort pulse laser such as a subsecond pulse laser is used, the pulse energy is high, so laser processing utilizing a multiphoton absorption process can be performed, and fine processing with a narrower width than the wavelength is performed by the power of the spire. Will be able to. Therefore, a micro-hole portion having a minimum diameter or width of 200 μm or less by laser processing using a multiphoton absorption process using an ultrashort pulse laser [particularly, the short diameter is 0.05 to 200 μm and the long diameter is 0 ..., .Mu.m or more (for example, 0.05 to 100000 .mu.m) can be formed. In addition, when the major axis is long, it may be an arbitrary shape such as a curved line or a bent line instead of a straight line.
[0028]
The wavelength of the ultrashort pulse laser is not particularly limited, and is a wavelength longer than the absorption wavelength (absorption peak wavelength or region thereof) of the resin component of the plastic substrate to be processed because it uses a multiphoton absorption process. It may be selected as appropriate according to the type of resin component of the plastic substrate to be processed or its absorption wavelength [absorption peak wavelength (particularly, main peak wavelength of absorption) or its region]. Specifically, the wavelength of the ultrashort pulse laser may be, for example, a wavelength in the ultraviolet region to the near infrared region, and can be appropriately selected from the range of 200 nm to 1000 nm. The wavelength of the ultrashort pulse laser is preferably a wavelength that is a harmonic (second harmonic, third harmonic, etc.) of the absorption wavelength (absorption peak wavelength) of the resin component of the plastic substrate to be processed.
[0029]
Further, the repetition of the ultrashort pulse laser is in the range of 1 Hz to 100 MHz, usually about 10 Hz to 500 kHz.
[0030]
The energy irradiated per unit volume inside the plastic substrate to be processed is the irradiation energy of the ultrashort pulse laser, the numerical aperture of the objective lens used when irradiating the plastic substrate to be processed (narrowing down the light source) ), The irradiation position on the plastic substrate to be processed or the depth of the focal point, the moving speed of the focal point of the laser, and the like.
[0031]
In the present invention, the average output or irradiation energy of the ultrashort pulse laser is not particularly limited, and can be appropriately selected according to the size and shape of the target microhole portion (particularly, the microthroughhole). It can be selected from a range of about 10,000 mW or less (for example, 1 to 1000 mW), preferably 5 to 500 mW, and more preferably about 10 to 300 mW.
[0032]
Further, the irradiation spot diameter of the ultrashort pulse laser is not particularly limited, and can be appropriately selected according to the size and shape of the target microhole, the size, numerical aperture, or magnification of the lens, for example, It can select from the range of about 0.1-10 micrometers.
[0033]
A lens can be used to focus the laser beam. That is, it is not necessary to use a lens when it is not necessary to focus the laser. The numerical aperture (NA) of such a lens is not particularly limited and can be changed according to the magnification of the objective lens. Usually, the magnification is 2.5 to 100 times, and the numerical aperture is 0.05. It is selected from a range of about ~ 0.95.
[0034]
As an example of a method for manufacturing a plastic structure having micropores by laser processing using a multiphoton absorption process, a pulse width of 10 ^-9 An example of a laser processing method using a laser with an ultrashort pulse of less than a second is shown below, but it is of course not limited to this laser processing method. Pulse width is 10 ^-9 For example, as shown in FIG. 5, a laser processing method using an ultrashort pulse laser of less than a second is applied to the surface and / or inside of a plastic substrate to be processed before forming a hole. Width is 10 ^-9 Examples of the method include forming a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less on a plastic substrate to be processed by irradiating an ultrashort pulse laser (ultrashort pulse laser) of less than 2 seconds. . FIG. 5 is a schematic bird's-eye view showing an example of a method for producing a plastic structure having a microscopic hole. In FIG. 5, 1 is a plastic film, 1a is an upper surface (front surface) of the plastic film 1, 1b is a bottom surface (back surface) of the plastic film 1, T is a thickness of the plastic film 1, and 3 is a pulse width of 10. ^-9 An ultrashort pulse laser of less than 2 seconds, 4 is a lens, and 5 is the focal point of the laser 3. Reference numeral 6 denotes an irradiation direction of the laser 3, and reference numeral 7 denotes a moving direction of the focal point 5 of the laser 3.
[0035]
In addition, 81, 82,..., 8n (n is an integer of 1 or more) are lines for moving the focal point 5 of the laser 3 in a line [hereinafter, the lines (81, 82,... ., 8n) may be collectively referred to as line 8]. Therefore, the line 8 extends in the same direction as the moving direction 7 of the focal point 5 or in the same direction. Since the line 8 is a line for moving the focal point 5 in a line shape, it corresponds to or corresponds to a trajectory in which the focal point 5 moves in a line shape (sometimes referred to as a “line-shaped movement trajectory”). Note that the line 8 includes one or more lines 81 to 8n, and each line has a parallel relationship.
[0036]
In addition, L indicates an interval between adjacent or adjacent lines (81, 82,..., 8n) in the line 8. The interval L is not particularly limited, and can be determined by the moving speed of the line. The interval L is usually selected from a range of about 5 to 10 μm. Note that the line interval can be controlled by providing a shutter in the irradiation device of the ultrashort pulse laser and using the shutter to cut off the optical path of the laser beam by the ultrashort pulse laser.
[0037]
In FIG. 5, the laser 3 irradiates the plastic film 1 in the direction of the irradiation direction 6, that is, in a direction parallel to the Z axis. The laser 3 can be focused by using the lens 4. The plastic film 1 has a film-like form, and the upper surface of the plastic film 1 is a plane parallel to the XY plane (or perpendicular to the Z axis). Note that the thickness T of the plastic film 1 forms a through-hole even if the laser 3 is irradiated without moving in the direction of the irradiation direction 6 (for example, the surface of the plastic film 1 is focused and irradiated). Specifically, the thickness may be, for example, about 0.1 to 10,000 μm.
[0038]
The laser 3 emits the focal point 5 while moving it in a line in the direction of the movement direction 7 (that is, the direction parallel to the Y axis). Therefore, as a result, the laser beam 3 is irradiated while moving the focal point 5 on the line 8 in a line shape in the direction of the moving direction 7. The moving direction 7 is a direction perpendicular to the irradiation direction 6 and parallel to the surface 1 a of the plastic film 1. Therefore, the line 8 is parallel to the moving direction 7 of the focal point 5 and is perpendicular to the irradiation direction 6. Further, the line 8 is in a direction parallel to the surface 1 a of the plastic film 1. The moving speed of the focus 5 when moving the focus 5 of the laser 3 in a line shape in the moving direction 7 is not particularly limited, and is, for example, 10 to 1,000,000 μm / second (preferably 100 to 10). , 000 μm / second).
[0039]
In this way, by irradiating the plastic film 1 with the laser 3 moving in the moving direction 7 that is perpendicular to the irradiating direction 6, through holes (individual holes on the surface of the plastic substrate to be processed) are formed. It is possible to form a through-hole having a shape in which the individual minute through-holes having a circular shape) are connected or a shape similar thereto (that is, a through-hole as a connecting hole). That is, a minute through hole having a minor axis and a major axis can be formed.
[0040]
In addition, when the plastic substrate to be processed is thick, drilling cannot be performed with one pulse, or when a hole with a long major axis is formed, a shutter is provided in the irradiation device of the ultrashort pulse laser, and line scanning is performed. The number of shots per unit area can be increased by controlling the optical path of the laser beam by the ultrashort pulse laser. This enables efficient laser processing with excellent accuracy even in the above cases. Can do.
[0041]
On the other hand, the independent hole portion (in particular, an independent minute through-hole or minute recessed hole whose plastic surface has a circular shape) is irradiated with the focal point 5 of the laser 3 stopped without moving, and the irradiation is performed. It can be formed by repeatedly irradiating in a stopped state with a gap from the formed part.
[0042]
Further, when the thickness of the plastic substrate to be processed is thick, when the drilling cannot be performed with one pulse, the focal point 5 of the laser 3 is set in a direction perpendicular to the direction of the irradiation direction 6 as shown in FIG. In the state where the movement of is stopped, the independent hole is also irradiated by irradiating the bottom surface (rear surface or the other surface) from the upper surface (front surface or one surface) while shifting the focal position in the Z-axis direction (that is, the irradiation direction 6). It is possible to form a portion (particularly, an independent minute through hole or minute recessed hole whose plastic surface has a circular shape). In this case, the focal point is moved from the start point 9a on the upper surface (front surface) side to the end point 9b on the bottom surface (back surface) side. The focal point moving speed in the Z-axis direction may be selected from a range of about 1 to 5,000 μm / second (preferably 10 to 800 μm / second).
[0043]
Furthermore, by linking the movement of the focal point 5 of the laser 3 in the Z-axis direction and the movement in the moving direction 7, for example, without moving the focal point 5 of the laser 3 in the moving direction 7, Z After moving in the axial direction, once the irradiation is interrupted, after returning to the Z-axis direction, moving in the moving direction 7 and resuming the irradiation are repeated, the through-hole as an independent hole portion (to be processed) It is possible to form a through hole having a shape in which the surface of the plastic substrate is formed into a circular shape (independent minute through holes) connected or a shape similar thereto (that is, a through hole as a connecting hole). .
[0044]
More specifically, the laser beam 3 is irradiated in the direction of the irradiation direction 6 with the focal point 5 being focused on one end of any one of the lines 8 (referred to as a line 81). The line 81 is moved to the other end of the line 81 in a line shape in the moving direction 7. Thereafter, the focal point 5 of the laser 3 is aligned with one end of the other line (referred to as a line 82) by the same method as the moving method of the focal point 5 on the line 81. Move to the shape. In addition, by repeating as many times as necessary such that the focal point is moved to one end of any one of the lines 8 and moved to the other end, the short diameter and long diameter (or minimum width and maximum length) are obtained. A plastic structure having a microhole portion (a microthrough hole or a microrecessed hole) having a shape with a
[0045]
Further, when forming the through hole, depending on the thickness of the plastic substrate to be processed, for example, when forming a micro through hole as an independent hole portion, as shown in FIG. Irradiation is performed in the direction of the irradiation direction 6, and the focal point is moved in a line from 9a to 9b or 9b to 9a in the direction of the irradiation direction 6 (Z-axis direction). After that, the movement of the focal point is stopped, the part different from the irradiated part is irradiated, and the focal point is moved in the irradiation direction 6 (Z-axis direction). Furthermore, by repeating the movement of the focal point in the irradiation direction 6 at different irradiation sites as necessary, a plastic structure having a minute through hole can be manufactured. In some cases, such as when the plastic substrate to be processed is thin, it can be formed without moving the focal point of the laser 3 in the irradiation direction 6.
[0046]
Of course, depending on the thickness of the plastic substrate to be processed, the movement of the focal point 5 of the laser 3 is combined with the movement in the direction of the movement direction 7 and the movement in the direction of the irradiation direction 6, A plastic structure having a minute through hole having a shape having a long diameter can be manufactured.
[0047]
The focal point of the ultrashort pulse laser can be moved by moving the relative position between the ultrashort pulse laser and the lens and the plastic structure, for example, by moving the ultrashort pulse laser and the lens and / or the plastic to be irradiated. This can be done. Specifically, the irradiation of an ultrashort pulse laser is performed, for example, by placing an irradiation sample (an irradiated plastic substrate to be irradiated) on a precise XYZ stage that can be moved precisely in two or three dimensions, By moving the sample three-dimensionally, the sample can be placed at an arbitrary place. Further, by setting the movement of the XYZ stage in terms of time, irradiation can be performed arbitrarily with three-dimensional continuity.
[0048]
In addition, by providing a shutter in the irradiation device of the ultrashort pulse laser, the optical path and irradiation of the laser beam of the ultrashort pulse laser can be controlled precisely and easily, and the laser processability by the ultrashort pulse laser is improved. Can do.
[0049]
In this way, the laser 3 is irradiated on the surface or inside of the plastic film 1 from the outside, and the focal point is formed in a line shape (a line shape parallel to the irradiation direction or perpendicular to the plastic surface or perpendicular to the irradiation direction as necessary). Alternatively, micropores (2a to 2d) as shown in FIGS. 1 to 4 can be formed on the surface of the plastic film 1 or the like. For example, a micro through hole as a single hole part depends on the thickness of the plastic substrate to be processed, but the laser is moved while moving the focal point (in a line) from one surface of the processed plastic substrate to the other surface. It can be formed by irradiation. The micro recessed hole as the single hole portion can be formed by irradiating the laser with the focus on the surface of the plastic substrate to be processed or the vicinity thereof while the focus of the laser is stopped without moving. . On the other hand, the micro through-hole as the connecting hole portion focuses the laser on or near the surface of the plastic substrate to be processed, and focuses the laser in a direction parallel to the surface of the plastic substrate to be processed (in a line shape). It can be formed by irradiating a laser while moving the shutter at a slower speed than the former and opening and closing a shutter provided in an ultrashort pulse laser irradiation apparatus as required. The micro-recessed hole as the connecting hole focuses the laser on or near the surface of the plastic substrate to be processed, and moves the laser focus in a direction parallel to the surface of the plastic substrate to be processed (in a line) It can be formed by irradiating with a laser.
[0050]
Note that the interval between the microholes [for example, the interval between the microholes on the adjacent lines of the microholes formed in a plurality of lines (that is, the direction perpendicular to the direction in which the lines 8 are formed) And the like, and the number of minute holes (for example, the number of independent holes and connecting holes on one line), etc., It does not restrict | limit in particular, It can select suitably according to the irradiation conditions of a laser, the raw material of the plastic base material to be processed, etc.
[0051]
(Plastic base material to be processed before forming holes)
In the present invention, the plastic substrate to be processed before the hole is formed is not only composed of a polymer material having a single chemical structure including a copolymer, but also composed of a plurality of polymer materials having different chemical structures. Polymer alloys and polymer blends can also be used. The processed plastic substrate used for pulsed laser irradiation may be a composite containing other materials such as inorganic compounds and metals in a dispersed state. Layers made of different plastics or other materials may be used. The laminated body which consists of two or more layered structures included may be sufficient. For example, in order to impart conductivity to a workpiece (plastic structure having micropores), a plastic substrate to be processed in which carbon black is dispersed in a material (polymer component) of the plastic substrate to be processed is used. As a result, the absorption efficiency of the laser beam is increased, and the effect of facilitating processing is also exhibited.
[0052]
Specifically, typical examples of the polymer material as the plastic substrate to be processed include, for example, methacrylate resins such as polymethyl methacrylate (PMMA); polystyrene, acrylonitrile-styrene copolymer (AS resin), and acrylonitrile. -Styrenic resin such as butadiene-styrene copolymer (ABS resin); Polyamide; Polyimide (PI); Polyetherimide (PEI); Polyamideimide; Polyesterimide; Polycarbonate (PC); Polyacetal; Polyarylene such as polyphenylene ether Polyphenylene sulfide; Polyarylate; Polyaryl; Polysulfone (polysulfone); Polyethersulfone (PES) (polyethersulfone); Polyurethanes; Polyethylene terephthalate Polyester resins such as PET (polyether); polyether ketones such as polyether ether ketone and polyether ketone ketone; polyacrylic acid esters such as polybutyl acrylate and polyethyl acrylate; polybutoxymethylene Polysiloxanes; Polysulfides; Polyphosphazenes; Polytriazines; Polycarboranes; Polynorbornene; Epoxy resins; Polyvinyl alcohol; Polyvinylpyrrolidone; Polydienes such as polyisoprene and polybutadiene; Polyisobutylene, etc. Polyalkenes; Fluorine resins such as vinylidene fluoride resin, hexafluoropropylene resin, hexafluoroacetone resin, polytetrafluoroethylene resin; polyethylene, polypropylene Ren, ethylene - (a thermoplastic resin) resins such as polyolefin resins such as propylene copolymer including without being limited thereto.
[0053]
The polymer material can be appropriately selected according to the use of the plastic structure having micropores. For example, in the use of filters, separators, etc., the polymer material is fluorine in consideration of chemical stability. A resin or an olefin resin can be preferably used.
[0054]
The thickness of the plastic substrate to be processed is not particularly limited, and can be appropriately selected according to the use of the plastic structure having a microscopic hole, for example, 0.1 μm or more (for example, 0.1 μm to 10 mm) ). Therefore, the plastic substrate to be processed may be a plastic sheet or film, or a plastic plate. When the plastic substrate to be processed is a plastic film, a plastic film having micropores can be obtained by laser processing using a multiphoton absorption process. In the present invention, even if the plastic substrate to be processed is a plastic film (that is, even if its thickness is thin), laser processing can be performed with excellent accuracy. When the plastic substrate to be processed is a plastic film, the thickness may be, for example, 0.1 to 500 μm (preferably 1 to 300 μm, more preferably 10 to 150 μm).
[0055]
Since the plastic structure having micropores manufactured by the method of the present invention has micropores (through-holes and depressions) that are precisely controlled on the surface and inside, the above-mentioned precision control is required. Various functions utilizing the micropores formed in this manner can be effectively exhibited. In particular, plastic structures with micropores, when they have microthroughholes, exhibit filter functions, membrane functions, separator functions, atomization functions, gas diffusion functions, nozzle functions, flow path adjustment functions, etc. can do.
[0056]
Specifically, the plastic structure having micropores according to the present invention is a micromachine or sensor, biodevice, microreactor chip, or implantable artificial organ that uses a spacer function to form a precise space or flow path. In addition, microfilters, microfiltration membranes, battery separators (for example, battery separators used in various batteries such as nickel metal hydride batteries and lithium ion batteries), fuel cell members (for example, gas diffusion layers, Various members used in fuel cells such as a current collecting layer, a moisture permeable layer, and a moisture retaining layer), micro nozzles (for example, micro nozzles for printers, micro nozzles for spraying, micro nozzles for spraying, micro nozzles for gaps), distributors, It can be used for various functional members such as gas diffusion layers and microchannels.
[0057]
In particular, when the plastic structure having a microporous portion is a plastic film having a microporous portion (particularly, a plastic film having microscopic through holes), a microfilter, a micromembrane, a battery separator, a fuel cell member, a micro It can be suitably used as a micro functional film member such as a nozzle. In addition, when using the plastic film which has a micro through-hole as a microfilter or a micromembrane, it can use suitably for the use of separation membranes, such as a separator for batteries, a member of a fuel cell, etc., and biotechnology.
[0058]
In addition, when using a plastic film having a microscopic through hole as a microfilter or a micromembrane, the microscopic through hole may have a minimum diameter or width of 200 μm or less. Specifically, as described above, The minor axis may be 0.05 to 200 μm, and the major axis may be 0.05 μm or more (for example, 0.05 to 100,000 μm). Of course, the major axis may be a straight line, or may be a curved line or a bent line. It is important that a large number of the fine through holes are provided in the plastic film, and the fine through holes may be provided in an orderly manner or may be provided randomly. Therefore, the interval between adjacent minute through-holes may be constant, or not constant but random. In addition, as described above, the shape of the micro through-hole on the film surface is a circular similar shape (such as a circular similar shape or an elliptical similar shape) or a rectangular similar shape (a square similar shape) from a macro or overall viewpoint. Or a rectangular-like shape).
[0059]
The plastic structure having a minute hole portion may be used as it is as a plastic member, or may be used in combination with other members. Arbitrary processing and processing can be performed on the plastic structure having a microscopic hole, for example, processing such as stretching and shrinking, and further post-processing can be performed as necessary.
[0060]
【Example】
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.
[0061]
(Example 1)
While moving from the surface of a polyimide (PI) film having a thickness of 0.025 mm to the back surface direction (the direction of the other surface or the back direction) at a moving speed of 8000 μm / s, the irradiation wavelength is 780 nm, the pulse width is 140 femtoseconds, and repeated. When a 1 kHz titanium, sapphire, femtosecond pulse laser was irradiated at an irradiation power of 50 mW and an objective lens magnification of 10 times under an irradiation spot of about 10 μm diameter, and then ultrasonically cleaned in pure water, A plastic having a through hole was obtained. When the plastic having the minute through holes was observed with an optical microscope, through holes having a diameter of 5 μm were formed at equal intervals of 8 μm.
[0062]
(Example 2)
The same pulsed laser as in Example 1 was applied to a polytetrafluoroethylene (PTFE) film (double-stretched product) having a thickness of 0.15 mm and 50% by weight of carbon black mixed with an irradiation output of 30 mW and a moving speed of 500 μm. The shutter was repeatedly opened and closed every second while scanning at / s. Then, when ultrasonic cleaning was performed in pure water, a plastic having minute through holes was obtained. When the plastic having the minute through holes was observed with an optical microscope, long groove-like through holes having a short diameter of 20 μm and a long diameter of 500 μm were formed at equal intervals.
[0063]
(Example 3)
On a 15 mm-thick polytetrafluoroethylene (PTFE) film (unstretched product), a YAG laser triple wave (wavelength 355 nm, pulse energy 50 nJ / pulse, 80 MHz) is condensed with a 5 × lens, Exposure was performed for 0.1 seconds, and then the exposure was repeated by moving 200 μm. Then, when ultrasonic cleaning was performed in pure water, a plastic having minute through holes was obtained. When the plastic having these minute through holes was observed with an optical microscope, through holes having a diameter of 20 μm were formed at equal intervals.
[0064]
Example 4
On a 0.05 mm thick polyethylene film, the same pulse laser as in Example 1 is separated into 5 light beams using a diffraction element with an irradiation output of 200 mW, and 4 diagonal light beams are condensed by a 5 × lens, When interference was generated on the polyethylene film, the polyethylene film was irradiated, and then ultrasonic cleaning was performed in pure water, a plastic having minute through holes was obtained. When the plastic having the minute through holes was observed with an optical microscope, four through holes having a diameter of 30 μm were formed at equal intervals.
[0065]
(Comparative Example 1)
While moving to the same film (PTFE film; thickness 0.15 mm, containing 50% by weight of carbon black, 2 times stretched product) as in Example 2 under the condition of 8000 μm / s, the irradiation wavelength was 1064 nm, the pulse width was 8 nanoseconds, Repeated irradiation with a 100 Hz Nd-YAG pulse laser was performed under the conditions of an irradiation output of 50 mW (500 μJ / pulse), an objective lens magnification of 10 times, and an irradiation spot diameter of about 10 μm, but no hole was formed.
[0066]
【The invention's effect】
According to the method for producing a plastic structure having a minute hole portion of the present invention, a hole portion having a minute diameter can be easily formed in plastic. Furthermore, a mask is unnecessary, and fine through holes and / or depressed holes can be formed with excellent productivity.
A plastic structure having micropores by such a manufacturing method can be used as a micro functional film member such as a microfilter, a micromembrane, a battery separator, a fuel cell member, or a micro nozzle.
[Brief description of the drawings]
FIG. 1 (a) is a schematic bird's-eye view schematically showing an example of a plastic structure having a minute through hole, and FIG. 1 (b) is an X-ray view in FIG. 1 (a). ₁ -X ₁ It is sectional drawing in a 'line.
FIG. 2 (a) is a schematic bird's-eye view schematically showing another example of a plastic structure having a minute through hole, and FIG. 2 (b) is a schematic view of X in FIG. 2 (a). ₂ -X ₂ It is sectional drawing in a 'line.
FIG. 3 (a) is a schematic bird's-eye view schematically showing an example of a plastic structure having a minute recessed hole, and FIG. 3 (b) is a cross-sectional view of FIG. 3 (a). ₃ -X ₃ It is sectional drawing in a 'line.
4 (a) is a schematic bird's-eye view schematically showing another example of a plastic structure having a micro-recessed hole, and FIG. 4 (b) is a schematic view of X in FIG. 4 (a). ₄ -X ₄ It is sectional drawing in a 'line.
FIG. 5 is a schematic bird's-eye view showing an example of a method for forming a plastic structure having micropores.
FIG. 6 is a schematic bird's-eye view showing another example of a method for forming a plastic structure having micropores.
[Explanation of symbols]
1 Plastic sheet
2a Through hole
2b Through hole
2c sinkhole
2d sinkhole
1a Top surface (surface) of plastic sheet 1
1b The bottom surface (back surface) of the plastic sheet 1
T thickness of plastic sheet 1
3 Pulse width is 10 ^-9 Ultrashort pulse laser that is less than a second
4 Lens
5 Focus of laser 3
6 Direction of laser 3 irradiation
7 Moving direction of focal point 5 of laser 3
8 Line when moving the focus 5 of the laser 3 in a line
L Distance between adjacent lines in line 8
9a Starting point on the upper surface (front surface) side at the focal point 5 of the laser 3
9b End point on the bottom surface (back surface) side at the focal point 5 of the laser 3

Claims (10)

A method of manufacturing a plastic structure having a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less as a hole, wherein the hole is formed by laser processing using a multiphoton absorption process. A method for producing a plastic structure having micropores. The method for producing a plastic structure having micropores according to claim 1, wherein the plastic substrate to be processed before forming the holes is a plastic sheet or film. The plastic structure having a micropore has a through-hole and has a filter function, a membrane function, a separator function, an atomization function, a gas diffusion function, a nozzle function, or a flow path adjustment function. A method for producing a plastic structure having micropores according to 1 or 2. The laser processing using a multiphoton absorption process is laser processing using an ultrashort pulse laser having a pulse width of 10 ^-9 seconds or less. A method for manufacturing a plastic structure. The production of a plastic structure having micropores according to claim 4, wherein the ultrashort pulse laser having a pulse width of 10 ^-9 seconds or less is an ultrashort pulse laser having a wavelength in the ultraviolet wavelength region to the near infrared wavelength region. Method. 6. The method for producing a plastic structure having micropores according to claim 4 or 5, wherein an ultrashort pulse laser having a pulse width of 10 <^-9> seconds or less is irradiated by multi-beam interference. Focus the ultrashort pulse laser with a pulse width of 10 ⁻⁹ seconds or less in a direction perpendicular to the irradiation direction of the ultrashort pulse laser and in a direction parallel to the plastic surface. The manufacturing method of the plastic structure which has a micropore part in any one of Claims 4-6 irradiated with moving. The plastic structure having a micropore according to any one of claims 1 to 7, wherein the plastic substrate to be processed before forming the hole contains a fluorine resin or an olefin resin as a material. Production method. The plastic structure having a micropore according to any one of claims 1 to 8, wherein the plastic substrate to be processed before forming the hole contains inorganic fine particles on the surface and / or inside thereof. Production method. 10. The plastic structure having a through hole and / or a recessed hole having a minimum diameter or width of 200 μm or less as the hole, wherein the hole is the micropore according to claim 1. A plastic structure having micropores, wherein the plastic structure is formed by a method for producing a plastic structure having a portion.

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