JPH02179941A - Optical information recording medium and its production - Google Patents

Abstract

PURPOSE:To enable visual check of a specified pattern on the surface of a recording medium without causing any influence of the formed pattern on recording/reproducing characteristics by making difference in intensity or color of reflected or diffracted light in the area corresponding to the pattern from other area. CONSTITUTION:If the fine signal patterns 5 in a macroscopic area 7 corresponding to the prescribed pattern 2 are made different in either shape or size from other signal patterns, diffraction effect in the area 7 differs from that in the other area to give different intensity or color of reflected or diffracted light from light in other area. If a photosensitive resin is provided on this substrate ad exposed to light, first to form uneven surface state and second to form the specified pattern, the projections or recessions in the pattern area differ from those in other area in shape or size. By this method, the obtd. optical information recording medium can have patterns of letters or images which can be visually checked without causing any trouble on recording/reproducing by an optical head.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical information recording medium, such as an optical disk or an optical card, on which a large amount of information is recorded or reproduced, and a manufacturing method thereof.

[Conventional technology]

In recent years, optical disks and optical cards have been proposed as large-capacity information recording media, and their application to various uses is being considered.

These optical information recording media record information by forming minute signal patterns of several microns to submicrons on the information recording surface, and then irradiate the recorded information with a light beam such as a laser beam. , and is reproduced by reading changes in the amount of reflected light.

[Problem to be solved by the invention]

On the surface of such an optical information recording medium, information such as its name, purpose of use, type, etc. is printed and displayed on a label or the like. However, these displays are performed in a very limited area, avoiding the recording and reproducing area on the surface of the optical information recording medium, so as not to interfere with recording and reproducing by the optical head of the recording and reproducing device. The content displayed was very limited in quantity.

By the way, the above-mentioned optical information recording medium has a minute pattern formed on its information recording surface as described above, and many of them have a beautiful appearance due to the diffraction effect of this pattern. There was a desire to increase added value by drawing patterns with readable characters and image information.

The present invention provides an optical information recording medium having a pattern such as a character or an image in the recording/reproducing area that does not interfere with recording/reproducing by an optical head of a recording/reproducing device and is visually readable from the outside, and a method for manufacturing the same. The purpose is to provide the following.

[Means to solve the problem]

In order to achieve the above object, an optical information recording medium according to the present invention has a minute signal pattern on its surface that can be read by a light beam, and the signal exists in a macroscopic area corresponding to a predetermined pattern. The pattern is
The structure is such that the pattern can be visually recognized on the surface by being different in at least one of its shape and size compared to the signal patterns of other parts.

When the signal pattern is convex or concave, the height of the convexity or the depth of the concave shape in the macroscopic region is relative to the height of the convexity or the depth of the concave shape in other parts. 1-30
It is preferable that the widths of the convex or concave portions differ within a range of 0%, or the width of the convex or concave portions may differ from the width of the convex or concave portions of other portions within a range of 1 to 500%. preferable. If the height change or width change of the convex or concave shape is less than 1%, the predetermined pattern will be difficult to see.
, while larger than 300% or 500%, respectively.
There is a risk that signal reading by the light beam will be hindered.

Further, the convex or concave shape may have a substantially triangular cross section or a substantially trapezoidal cross section in the direction perpendicular to the trunk.

Further, when the signal pattern is a planar reflectance changing portion, the width of the planar reflectance changing portion in the macroscopic region is within a range of 1 to 500% of the width of other portions. It is preferable that they are different. If the change in the width of the planar reflectance changing portion is smaller than 1%, it will be difficult to visually recognize the predetermined pattern, while if it is larger than 500%, there is a risk that signal reading by the light beam will be hindered.

Further, the manufacturing method for manufacturing the optical information recording medium having the convex or concave shape as a signal pattern includes a step of forming a photosensitive resin layer on one surface of a substrate, and a step of forming a photosensitive resin layer on one surface of a substrate. A first exposure in which the exposure intensity is varied in accordance with the signal pattern and a second exposure in which the exposure intensity is varied in correspondence to the predetermined pattern are applied simultaneously or either one to the surface of the printed substrate. a step of developing the substrate, a step of creating a stamper using the developed substrate, and a step of creating a replica of the optical information recording medium using the stamper. It is preferable that

The first exposure and the second exposure may be performed using a first mask and a second mask each having a predetermined pattern formed thereon, in which case the second mask may be used as a plurality of masks. Good too.

Further, by providing a light attenuation means with a pattern corresponding to the pattern between the exposure light source and the substrate, or by providing the substrate with a light-transmitting material and disposing the exposure light source on the side opposite to the exposure light source with respect to the substrate. By providing a reflecting means with a pattern corresponding to the pattern, the first exposure and the second exposure can be performed simultaneously.

The stamper that can be used in the above-described manufacturing method has a convex portion or a concave portion, and the convex portion or the concave portion corresponding to the signal bag existing in the macroscopic region is
Compared with the convex portion or the concave portion corresponding to the signal pattern of other portions, the shape and/or size thereof are different from each other.

Further, a photomask that can also be used in the above manufacturing method has an opening and/or a dark area, and the opening or the dark area corresponding to the signal pattern existing in the macroscopic area is different from the other one. The opening portion or the dark portion corresponding to the signal pattern of the portion is different from each other in at least one of its shape and size. Even if such a photomask is used, the first exposure and the second exposure
can be performed at the same time.

Further, in the method for manufacturing the optical information recording medium having the planar reflectance changing portion as a signal pattern, the method includes a step of forming a photosensitive film on one surface of the substrate, and a signal pattern existing in the macroscopic region. using a photomask in which the openings or dark areas corresponding to the signal pattern are different in at least one of the shape and size compared to the openings or dark areas corresponding to the signal pattern in other parts, respectively. It is desirable to have a configuration including a step of forming a planar reflectance changing portion by exposing the film to light.

[Effect]

If a minute signal pattern existing in a macroscopic area corresponding to a predetermined pattern is different in either shape or size compared to signal patterns in other parts, it may be different from the macroscopic area. The pattern is visible on the surface because there is a difference in the diffraction effect from other parts, and the intensity and hue of the reflected diffracted light in that macroscopic area differs from those in other areas.

Further, when a photosensitive resin layer is provided on a substrate and a first exposure for forming a convex or concave shape and a second exposure for forming the pattern are performed, macroscopic images corresponding to the pattern are formed. The shape or size of the convex or concave shape existing in the area can be made different from that in other parts. Further, when a photosensitive coating is formed on a substrate and then exposed using a photomask according to claim I6, the width of the planar reflectance changing portion formed in the macroscopic region is different from the width of other portions. It can be compared and made different.

〔Example〕

Embodiments of an optical information recording medium to which the present invention is applied and a method for manufacturing the same will be described below with reference to the drawings.

First, an example will be described in which a pattern 2 (letter "K" in this example) is formed on an optical card l on which a large amount of information is recorded and reproduced as an optical information recording medium as shown in FIG.

Optical cards 1 are generally classified into write-once optical cards that allow additional recording and read-only cards that allow only reading. In the case of the former write-once optical card, prerecorded information and additionally recorded information are recorded separately, and the prerecorded information includes, for example, tracking, clocking, and address information.

This embodiment is a case of a write-once optical cart, in which a large number of tracking trunks 3 are linearly provided at regular intervals in the planar longitudinal direction of an optical card 1 as shown in FIG. As shown in FIG. 2, a clock track 8 is linearly provided in the longitudinal direction of the center of the area existing between the tracking tracks 3, and a pair of clock tracks 8 is provided between the clock track 8 and the tracking track 3. Recording area 4
is provided. Further, the recording area M4 is divided into a pre-recording area 4a and an additional recording area 4b. For example, address information is recorded in the pre-recorded area 4a.

Tracking track 3 and clock track 8 described above
In this embodiment, the minute signal patterns 5 formed in the prerecorded areas 4a and 4a are each formed in a convex shape having a substantially triangular cross section in the direction perpendicular to the track. The convex shape in the tracking trunk 3 is formed in a straight line, and the convex shapes in the clocking trunk 8 and the pre-recorded area 4a are formed intermittently at predetermined lengths.

Further, the additional recording area 4b is flat so that necessary information can be written during use, and bits can be formed there using, for example, a laser beam. in this case,
When reading these information records, even if convex and pit-like concave objects coexist, the reading light beam will be scattered in the same way, so there will be no problem in reading.

FIG. 3A shows a cross-sectional view of the convex shape as the signal pattern 5. The convex shape 11 exists in the region 7 corresponding to the pattern 2, and has a width W of 3.8 μm and a height, for example. The thickness is 0.7 μm. Moreover, the convex shape 12 is the pattern 2 mentioned above.
For example, the width Wt is 4.0 μm and the height h2 is 0.8 μm. Note that 31 is a reflective coating for reflecting the light beam.

As mentioned above, for example, the convex shape 11 is different from the convex shape 12 in that its width is reduced by 5.0% and its height is reduced by 12.5%, but the convex shape 11 corresponds to the pattern 2. Area 7
The convex shapes 12 collectively exist in a region 6 that does not correspond to the pattern 2. Therefore, the intensity or hue of the reflected diffraction light in the region 7 is different from that in the region 6, and as shown in FIG.
characters can be visually recognized.

By the way, in each of the same pre-recorded area 4a, the same tracking track 3, and the same clock trunk 8 of the optical card 1, the convex shape 11 and the convex shape 1
If the height and width of the triangular cross section are different from those of the optical card 1, there is a risk of problems such as noise occurring when the optical card 1 is reproduced. Additionally, additional recording and reading could be carried out without any problems.

Furthermore, according to the inventors' studies, in the case of the convex shape 11 of this embodiment, the width of the convex shape 11 is up to 500%, and the height of the convex shape 11 is up to 300%. Even if the width or height of the strip 12 was different, reading, tracking, etc. as described above could be performed without any problem.

In addition, in order to visually recognize the pattern 2, the width and height of the above-mentioned convex shapes 11 need only differ by about 1%, but if the pattern 2 is, for example, a painting, the convex shapes that do not vary as much as these may differ. Even if the pattern 2 exists within the area 7, the entire pattern 2 may be visible.

FIG. 3B shows a modification of the shape of the signal pattern 5.

In this case, the shape is a concave shape having a substantially trapezoidal cross section, and the concave shape 13 exists in the region 7 corresponding to the pattern 2, and the width W of the opening on the surface on which the reflective coating 31 is formed is, for example, 3.2 μm. , depth d.

is 0.7 μm. Further, the concave shape 14 exists in the region 6 that does not correspond to the pattern 2, and has a width W4 of, for example, 3.5. crm, and the depth d2 is 0.8 μm.

In this case as well, the pattern 2, for example, the letters l''KJ, could be visually recognized, and tracking, additional recording, and record reading could be performed without any problems. In the case of a concave shape, the width of the cross-sectional shape is 1 to 500%, and the depth is 1 to 300%.
It can be changed up to %.

Note that the degree of change in each of the shapes described above needs to take into consideration the interval between the tracking tracks 3 and the spot diameter of the light beam emitted from the optical head of the recording/reproducing apparatus.

Next, a method for manufacturing an optical information recording medium, for example, an optical card 1, on which the pattern 2 is formed will be described with reference to Examples 1 to 7.

The manufacturing steps A to J of this embodiment are shown in FIGS. 4A to 4J, and the manufacturing steps will be explained in this order. In addition, each code|symbol of process AJ and each alpha vent of a drawing number correspond.

A. A glass substrate 21 with a diameter of 127 cm and a thickness of 1.4 mm was washed with Freon and dried, and then a photoresist (manufactured by Fuji Hunt Electronics Technology Co., Ltd., WAYCO) was applied.
AT[F]HPR204) was applied using a spin code method so that the dry thickness was 0.9 μm, and then prebaking was performed at 110° C. for 30 minutes in a convection open environment to form the photoresist layer 22. .

B. l - A first opening consisting of a line pattern opening with a width of 3 μm for forming the rough king track 3 and an opening with a focus pattern of a width of 3 μm and an arbitrary length for address information recording and clock trunk 8; Photomask 2
The first exposure was performed using No. 3. The exposure conditions in this case were as follows.

Exposure machine: PLA501 manufactured by Canon F Exposure energy: 26 mJ/cJ Print gap = 10 μm As C1 pattern 2, for example, the alphabet "K" (see Figure 5) is written in Gothic font with a line width of 3I and a size of 20 squares in black. Second photomask 24 with drawn dark areas 34
using the exposure light source 3 on the mask side as shown in FIG.
5 was placed, and a second exposure was performed. At that time, apply the second photomask 2 so that the letters rKJ are in the specified position.
4 was positioned. The exposure conditions in this case were as follows.

Exposure machine: manufactured by Canon, PLA501F Exposure energy: 5 m J/c Sibrint gap = 50 μm By performing the second exposure as described above, the area 7 corresponding to the letters rKJ is exposed to less light than the other areas 6. The exposure in region 7 was less than in region 6 because the intensity was reduced.

D. The glass substrate 21 subjected to the second exposure is immersed in a developer, and the exposed portions of the photoresist are dissolved and removed, thereby creating recesses 15 corresponding to the pattern on the photoresist layer 22. was formed.

After the development, the glass substrate 21 was heat-treated at 140° C. for 60 minutes in a convection oven.

E. A nickel film 25 with a thickness of 750 mm is formed by sputtering on the surface on which the recess 15 is formed to serve as a conductive film for electroforming, and then a nickel layer is formed on this surface by electrodeposition and peeled off. Electroforming was performed to obtain a stamper master 26 with a fin thickness of 0.6.

F. This stamper master 26 was again subjected to nickel electroforming to obtain a stamper mother 27.

G. Nickel electroforming was further performed on the stamper mother 27 to obtain a molding stamper 28 having a convex portion 19 and having a thickness of 0.3 mm.

H1 Using the above molding stamper 28, heat press mold a 0.4 mm thick polycarbonate sheet (Kijin Kasei, Panlite MR Sheet) as a base material for the replica 29 to create a replica 29, and fill the above recess 15 with the molding stamper 28. A corresponding recess 5a was formed on the surface of the replica 29. Note that a surface hardening layer 30 is formed with a silicone surface hardening agent on the opposite surface of the polycarbonate sheet from the hot press molding surface.

When the recess 5a formed on the surface of the replica 29 was inspected using a stylus surface roughness meter (manufactured by Rank Taylors Hobson, Kristetsub), it was found that the recess 5a was present in the region 7 corresponding to the letters rKJ. The shape of 5a has a depth of 0.7 μm and a width W! 3.
It had a concave shape with a smooth triangular cross section of 8 μm. and,
The shape of the recess 5a existing in the region 6 not corresponding to the letters rKJ was a similar triangular cross-section with a depth (h2) of 0.8 μm and a width W2 of 4.0 μm. Also,
The overall warpage of Replica 29 is up to 3 mm in the longitudinal direction.
It was about. Moreover, no damage was observed in the surface hardened layer 30.

(2) On the surface of the replica 29 on which the recess 5a is formed, a reflective coating 31 made of an alloy of platinum, tellurium, and selenium in an atomic ratio of 5:20 is formed to a thickness of 360 mm by sputtering. did.

J, forming an adhesive layer 32 using a polyurethane adhesive on the surface of the recording film 31 formed on the replica 29;
Through this, a white polycarbonate sheet (manufactured by Kijin Kasei Co., Ltd., Panlite ■ sheet) containing TiO□ and having a thickness of 0.3 m was adhered as a backing base material 33. Thereafter, the optical card 1 was obtained by punching the replica 29 into a size of 54++nX85.511-.

Note that in the drawing shown in FIG. 4J, the optical card I is used so that the light enters from above, so the recess 5
In this case, a had a convex shape with a triangular cross section.

Further, the molding stamper 28 has a convex portion 19, and the height and width of the convex portion 19 in the portion corresponding to the region 7 are different from the convex portion in the portion corresponding to the region 6. They are formed to be smaller than the height and width of the shaped portion 19, respectively, and one of them almost matches the dimensions of the concave portion 5a on the replica 29 corresponding to the convex portion 19.

In this example, steps A to H were the same as in Example 1 above, except that the heat treatment conditions in the steps were changed to 120°C and 30 minutes.
After that, replica 29 was obtained.

Example 1 The recess 5a formed on the surface of this replica 29
When inspected in the same manner as above, it was found that the shape of the recess 5a existing in the region 7 corresponding to the letters rKJ has a depth d of 0.7.
μm, and the width W of the lower side of the opening on the replica 29 surface is 3.
It has a trapezoidal concave shape with a width of 2 μm and an upper side width of 1.2 μm, and r
The recess 5a existing in the area 6 that does not correspond to the letters KJ
The shape has a depth d2 of 0.8 #m and a bottom width W4 of 3.5 m.
．． cam had a trapezoidal concave shape with an upper side width of 1.5 μm. Further, the warpage of the replica 29 and the state of the surface hardening layer 30 were also the same as in Example 1.

Step 1 in Example 1 described above using the replica 29. Optical card 1 was obtained through the same process as J.

In this example, a photomask 37 was first obtained as follows. That is, the first photomask 23 itself used in step B of Example 1 described above is written in Gothic font with a line width of 3 and a size of 2.
It was covered with a mask with the letter "K" carved out in the dragon horn. Next, by forming a chromium film on such a surface by sputtering so that the light transmittance is reduced to 90%, a light attenuation fi 36 with the letters rKJ is provided on the first photomask 23. Ta. Thereafter, the mask with the "K" cut out was removed to obtain a photomask 37. Using a photomask 37 having such a light attenuation layer 36 as a light attenuation means, and with an exposure light source 35 disposed on the photomask side as shown in FIG. 6, first exposure was performed under the following conditions.

Exposure machine: manufactured by Canon, PLA501F Exposure energy: 30mJ/cIA Print gap: 108m Using the above photomask 37, the first exposure and the second
Exposure was also carried out. At this time, the exposure intensity of the area 7 corresponding to the letters rKJ is reduced by the light attenuation layer 36 with the letters rKJ on the photomask 37 compared to other areas 6, so the exposure amount in the area 7 is It was less than the case of 6.

Except for the above points, steps A and B in Example 1 described above
, a replica 29 was obtained through the same steps as DH. When the four parts 5a formed on the surface of this replica 29 were inspected in the same manner as in Example 1, the shape of the recess 5a existing in the region 7 corresponding to the letter "K" had a depth (hl) of 0. 7
．． The shape of the recess 5a, which has a smooth triangular cross section with El m and width W of 3.8 μm, and exists in the region 6 that does not correspond to the letter “K” has a depth (h2) of 0.8 μm.
, had a concave shape with a similar triangular cross section and a width W=4.0 μm.

Further, the warpage of the replica 29 and the state of the surface hardening layer 30 were also the same as in Example 1.

Using the replica 29, an optical card 1 was obtained through the same steps as steps (2) and (J) in Example 1 described above.

In this example, the replica 29 was obtained through the same steps (however, step C was omitted) except that the steps A and B in the above-mentioned Example 1 were different as follows.

That is, the glass substrate 21 used in the above step A was covered with a mask in which the alphabet "K" with a line width of 3 layers and a size of 20 am square was hollowed out in Gothic font. Next, a chromium film is sputtered on this surface so that the reflectance of light incident through the glass substrate 21 is 20% as shown in FIG. 7A.
By forming the glass substrate 2 so that
A reflective film 39 shaped like the letter "K" was provided on top of the reflective film 39. next,
After removing the mask in which the rKJ was hollowed out, the glass substrate 21 is
A photoresist layer 22 was formed on the surface on which the chromium reflective film 39 was not formed.

Next, as shown in FIG. 7B, the photoresist layer 22 is
A first photomask and an exposure light 1lI35 were placed on the side where the was formed, and the first exposure was performed under the same conditions as in step B of Example 1 described above.

As described above, the reflecting means corresponding to the letters rKJ, that is, the chrome reflecting film 39, was provided on the surface of the glass substrate 21, and the first exposure was carried out from the opposite side, and the second exposure was also carried out at the same time. At this time, as shown in FIG. 7C, the above rK
The light from the first exposure is reflected by the reflective film 39 shaped like the letter "J" and the exposure intensity in the area 7 corresponding to the letter "K" is increased compared to other areas 6, so that the exposure in the area 7 is increased. The amount was higher than in area 6.

When the recess 5a formed on the surface of the replica 29 obtained as described above was inspected in the same manner as in Example 1, it was found that rKJ
The shape of the recess 5a existing in the area 7 corresponding to the letters rKJ is a concave shape with a smooth triangular cross section with a depth (hl) of 0.8 μm and a width w1 of 4.0 μm, and the area not corresponding to the letters rKJ The shape of the recessed portion 5a existing at 6 has a depth (
It had a similar concave triangular cross section with h2) of 0.7 μm and width wz of 3.8 μm. Further, the warpage of the replica 29 and the state of the surface hardening layer 30 were also the same as in Example 1.

Step 1 in Example 1 described above using the replica 29. An optical card 1 was obtained through the same process as J.

In this example, the replica 29 was obtained through the same steps (however, step C was omitted) except that the step B in the above-mentioned example 1 was different as follows.

That is, a polyethylene terephthalate film having a diameter of 127 mm and a thickness of 100 μm was covered with a mask in which the alphabet "K" with a Gothic font with a line width of 3 cranes and a size of 20 mm was cut out. Next, a chromium film is formed on this surface by sputtering so that the reflectance of light incident through the polyethylene terephthalate film is 20%, and a reflective film 4 with the letters rKJ is formed on the film.
1 was established. Next, the mask in which the rKJ was hollowed out was removed, and this was used as the underlay film 42.

As shown in FIG. 8, the underlay film 42 is positioned on the opposite side of the exposure light source 35 with respect to the glass substrate 21, and the first exposure is performed using the first mask 23 under the same conditions as in Example 1. I went there.

As described above, the underlay film 42 having the reflective film 41 corresponding to the letters rKJ is placed on one surface of the glass substrate 21, and the first exposure is performed from the other surface and the second exposure is simultaneously performed. Ta. At this time, the 7th C of Example 4 above
Similarly to the figure, the exposure amount in area 7 corresponding to the letter "K" was greater than in area 6.

When the recess 5a formed in the replica 290 surface obtained as described above was inspected in the same manner as in Example I, it was found that rKJ
The shape of the recess 5a existing in the region 7 corresponding to the letters rKJ is a concave shape with a smooth triangular cross section with a depth (hl) of 0.8 μm and a width w1 of 4.0 μm, and the shape of the recess 5a existing in the region 7 corresponding to the letters rKJ is a concave shape with a smooth triangular cross section. The shape of the recess 5a existing in the depth (
It had a similar concave triangular cross section with h2) of 0.7 μm and width w2 of 3.8 μm. Moreover, the state of the warp and surface hardening N30 of the replica 29 was the same as in Example 1.

Step 1 in Example 1 described above using the replica 29. Optical card 1 was obtained through the same process as J.

9A to 9G show manufacturing steps A' to G' of this embodiment, and will be explained in this order.

A', a photoresist was applied to one surface of the glass substrate 21 described above, and after drying, a conductive film for electroforming was formed on this surface by sputtering, and then nickel was electroformed to a thickness of 0.3 fin. . As a result, a nickel substrate 44 for the stamper mother with a smooth surface was obtained, and this was
Processed to 05ms.

B': After the nickel substrate 44 was Freon-cleaned and dried, a photoresist (same as in Example 1) was applied using a spin code method to a dry thickness of 1.9 μm. A photoresist layer 22 was formed by performing the same prebaking as in 1.

G', the first exposure was performed using the same first photomask 23 as in Example 1 under the following conditions.

Exposure machine: Mikasa Mask Aligner MA-20 Exposure energy: 18 mJ/cJ Print gap: None (hard contact exposure) D', second exposure using the same second photomask 24 as in Example 1 I went under these conditions.

Exposure machine: Mikasa Mask Aligner MA-20 Exposure energy: 2 m J / cd Print gap: None (hard contact exposure) E', The nickel substrate 44 that has been exposed above is immersed in a developer, and the same process as in Example 1 is carried out. A recess 15 was formed on the photoresist layer 22.

After development, heat treatment was performed at 140"C for 160 minutes in a convection oven.

F', Argon plasma etching is performed under the following conditions on the surface of the nickel substrate 44 on which the photoresist Ji522 has been formed after the development has been completed (see FIG. 9F) to simultaneously remove the photoresist and nickel. Etched.

Equipment used: CFS-8EP-55 made by other country manufacturing companies Argon gas pressure = 5 x 10-'Torr Applied voltage = 150
W Etching time: 4 hours 45 minutes Most of the photoresist layer 22 is removed by the above etching, and at the same time, a recess 16 is formed on the nickel substrate 44 corresponding to the recess 15 formed on the photoresist layer 22. It was done. A nickel substrate 44 having a recess 16 as described above was used as a stamper mother 44.

G', using the mother 44, the convex part 1 is formed by electroforming.
A molding stamper 28 having a diameter of 9 was obtained.

H': A replica 29 was obtained using the molding stamper 28 in the same manner as in Example 1.

When the recess 5a formed on the surface of the replica 29 was inspected in the same manner as in Example 1, it was found that the shape of the recess 5a existing in the region 7 corresponding to the letters rKJ had a depth (hl) of 0.70 μm. The shape of the recess 5a, which has a triangular cross section with a width W2 of 3.8 μm and exists in the region 6 not corresponding to the letters rKJ, has a depth (h2) of 0.75. Um,
It had a similar concave triangular cross section with a width W2 of 4.0 pm. Further, the warpage of the replica 29 and the state of the surface hardening layer 30 were also the same as in Example 1.

Step 1 in Example 1 described above using the replica 29. An optical card 1 was obtained through the same process as J.

1111 This embodiment is a method of manufacturing an optical card in which the signal pattern 5 is a planar reflectance change, and manufacturing steps A" to D" are shown in FIGS. 10A to 10D and will be explained in this order.

A" has a line pattern opening with a width of 3.5 μm for forming the tracking trunk 3 and a pit pattern opening with a width of 3.5 μm and an arbitrary length for recording address information and clock track 8. , and a Gothic font with a line width of 3m■ and a size of 2 (In corner alphabet "K").
'', a photomask 46 having an opening width of 4.0 μm in the line pattern was fabricated using IC photomask technology.

The photomask 46 as described above was exposed to light in almost intimate contact with the photosensitive coating 47.

B″, the photosensitive film 47 was developed to form a blackened portion 18 corresponding to the opening of the photomask 46 described above. When this blackened portion 18 was observed with a microscope, Width W of the blackened portion 18 existing in the region 7 corresponding to the letters rKJ.

is 4 μm, and the area 6 that does not correspond to the letters rKJ above
The width wh of the blackened portion 18 present in the sample was 3.5 μm.

C'', a platinum-telluroselenium alloy film 49 (atomic ratio 5 near 5
:20) was deposited to a thickness of 360 mm.

D'', transparent adhesive layer 32 on both sides of the photosensitive coating 47
was formed, and a pair of transparent polycarbonate sheets 48a and 48b were bonded through this.

In this case, the polycarbonate sheet 48b and the adhesive in contact with it do not need to be transparent.

An optical card 1 was obtained through the steps described above. Note that the blackened portion 18 and other non-blackened portions (portions other than the signal pattern 5 in FIG. 2) are uniformly covered with the platinum-tellurium-selenium alloy film 49; Since the reflectance of the alloy film 49 is not 100%, the blackened portion 18 absorbs a large amount of light, and the non-blackened portion reflects light to a large extent. Therefore, the blackened portion 18 and the non-blackened portion could constitute a planar reflectance changing portion which is the signal pattern 5 of the optical card 1.

For each of the optical cards 1 obtained in Examples 1 to 7 above, write-once recording and reading tests were conducted under the following conditions.

Wavelength: 830 nm Beam diameter = 4.0 μm (half width) Write power: 10 mW Write time: 20 μs Read power: 0.4 mW As a result, additional recording, recording reading, and tracking were all performed without any problems, and it also corresponded to the letters rKJ. area 7
There was no difference in the results of the above test in the non-corresponding areas 6 and 6.

Further, the line pattern of the optical card 1 had good contrast in both areas 6 and 7. Since the hue of the reflected diffracted light in the region 7 is different from that in the region 6, the r
The letters KJ were clearly visible.

As described above, in Example 1, by performing the first exposure and the second exposure, a convex shape is formed as the signal pattern 5 for predetermined pre-recording, and further a predetermined pattern 2 is formed on the optical card l. was able to form. The optical card 1 could be easily replicated using the molding stamper 28 described above. Further, in Example 2, the shape of the convex shape was changed by changing the post-development heat treatment conditions in Example 1, but there was no difference in the results of the above test. Further, in Examples 3 to 5, the second exposure could be performed simultaneously with the first exposure. Furthermore, in Example 6, the standby mother could be made directly from a metal substrate such as a nickel substrate by etching. Furthermore, in Example 7, a planar reflectance changing portion could be easily formed as the signal pattern 5 using the photomask 46 described above.

Note that, for example, when the above-mentioned second exposure is performed using the second photomask 24, the number of the second photomask 24 is not limited to one, and a plurality of light transmitting photomasks may be used. Exposure can be carried out in stages, thereby making it possible, for example, to form a complex pattern 2. It is also possible to carry out the second exposure with a hologram, thereby obtaining the pattern 2 of the hologram image. Further, the first and second exposures may be performed using a laser drawing device. The first exposure may be performed with a laser cutting device.

Further, the first exposure may be performed using the photomask 46 used in the seventh embodiment described above, and in this case, the second exposure can also be performed at the same time.

Further, the method for creating the replica 29 using the molding stamper 28 may be an injection molding method, a 2P method, or the like.

Further, although this embodiment uses an optical card, the present invention can also be applied to other optical information recording media such as optical discs and laser vision discs.

Furthermore, the present invention is not limited to this embodiment, and other modifications are possible based on the technical idea of the present invention.

〔Effect of the invention〕

Since the present invention has the above-described configuration, it produces the effects described below.

On the surface of the optical information recording medium, the intensity and hue of the reflected and diffracted light in a region corresponding to a predetermined pattern are different from those in other regions, so that the pattern is visible on the surface, and the pattern is formed. There is no effect on recording and playback.

Further, the optical information recording medium as described above can be obtained extremely easily by performing exposure corresponding to the predetermined pattern.

[Brief explanation of the drawing]

Figures 1 to 3B relate to the optical card of this embodiment. Figure 1 is a plan view of the optical card, Figure 2 is a partially enlarged plan view of the optical card shown in Figure 1, and Figure 3A is a plan view of the optical card. FIG. 3B is an enlarged perspective view of a convex shape with a triangular cross section formed as a signal pattern of an optical card, showing the cross section together, and FIG. FIG. 3 is a perspective view showing a cross section together. Figures 4A to 1 OD relate to Examples 1 to 7 of the optical card manufacturing method, and Figures 4A to 4J are schematic side sectional views showing the steps of Example 1; 5 is a perspective view showing the second exposure state in step C of Example 1, FIG. 6 is a perspective view showing the exposure state of Example 3, and FIG.
Figure A is a perspective view showing a state in which a pattern is formed on the glass substrate of Example 4, Figure 7B is a perspective view similarly showing a state of exposure, and Figure 7C is a view taken along arrows ■C-■C in Figure 7B. FIG. 8 is a perspective view showing the exposure state of Example 5, and FIGS. 9A to 9
Figure H is a schematic side sectional view showing the process of Example 6,
0A to 10D are schematic side sectional views showing the steps of Example 7. In addition, in the symbols used in the drawings, 1 ・・・・−・−・−・−・−・−・−Optical card 2−
・−・・・−・−・−・・−−１−− Pattern 5−・・・・
・・−・−・・−・−・−・・− Signal pattern 7 ・
-------Area corresponding to pattern 2 11.12 --- Convex 13, 14 --- Concave 18 −・・−・・−・・−・・1‐1 Blackened part I9
−・−・−・・−・・・・・・Convex part 22 of molding stamper ・・・・・・−・・・−・・−・・−
・Photoresist layer 23 ・−・・−−・・・−
......First photomask 24-...----
−−−・−・−・・Second photomask 37 ・・
-・・−・−・・・・・・Photomask 39 with light attenuation means −・・・・・・・・・・・・・Reflection film 42 −・−・−・・・・−・−・Underlay film 46 with reflective film 46−・・−・−・−−−−−1・−1−−−・−Photomask 47−・−−1−−−−−−・−
...-----It is a photosensitive coating. Photolist layer

Claims (1)

[Claims] 1. In an optical information recording medium having a minute signal pattern on its surface that can be read by a light beam, the signal pattern existing in a macroscopic area corresponding to a predetermined pattern is
An optical information recording medium characterized in that the pattern can be visually recognized on the surface because at least one of its shape and size is different from that of the signal pattern in other parts. 2. The optical information recording medium according to claim 1, wherein the signal pattern has a concave or convex shape. 3. The optical information recording medium according to claim 2, wherein the signal pattern has a concave or convex shape having a substantially triangular cross section. 4. The optical information recording medium according to claim 2, wherein the signal pattern has a concave or convex shape having a substantially trapezoidal cross section. 5. The depth of the concave or the height of the convexity in the macroscopic region is relative to the depth of the concave or the height of the convexity in other parts,
3. The optical information recording medium according to claim 2, wherein the difference is within a range of 1 to 300%. 6. The width of the concave or convex shape in the macroscopic region is different from the width of the concave or convex shape in other parts within a range of 1 to 500%. optical information recording media. 7. The optical information recording medium according to claim 1, wherein the signal pattern is composed of a planar reflectance changing section. 8. The width of the planar reflectance changing portion in the macroscopic region is 1 to
8. The optical information recording medium according to claim 7, wherein the difference is within a range of 500%. 9. A stamper having a convex portion or a concave portion used for manufacturing an optical information recording medium according to claim 2, wherein the convex portion or the concave portion corresponding to a signal pattern existing in the macroscopic area is A stamper characterized in that at least one of the shape and size of the convex portion or the concave portion is different from that of the convex portion or the concave portion corresponding to a signal pattern of another portion. 10. A photomask having an opening and/or a dark area used for manufacturing the optical information recording medium according to claim 2 or 7, wherein the opening or the dark area corresponding to a signal pattern existing in the macroscopic area is . A photomask, wherein at least one of the shape and size thereof is different from that of the opening or the dark area corresponding to a signal pattern of another portion. 11. The method for manufacturing an optical information recording medium according to claim 2, comprising: forming a photosensitive resin layer on one surface of a substrate; and forming a signal pattern on the surface of the substrate on which the photosensitive resin layer is formed. A step of performing a first exposure with a correspondingly changed exposure intensity and a second exposure with a correspondingly changed exposure intensity corresponding to the predetermined pattern, at the same time or one of them; and developing the substrate. A method for manufacturing an optical information recording medium, comprising: a step of creating a stamper using the developed substrate; and a step of creating a replica of the optical information recording medium using the stamper. 12. Performing the first exposure using a first mask in which openings or dark areas corresponding to the signal pattern are formed, and forming one or more masks in which openings or dark areas in a pattern corresponding to the pattern are formed. 12. The manufacturing method according to claim 11, wherein the second exposure is performed using the second mask. 13. The first exposure and the second exposure are performed simultaneously by providing a light attenuation means with a pattern corresponding to the pattern between the exposure light source and the substrate. Production method. 14. The substrate is made of a light-transmitting material, and a reflecting means having a pattern corresponding to the pattern is provided on the side opposite to the exposure light source with respect to the substrate, and the first exposure and the second exposure are performed simultaneously. The manufacturing method according to claim 11, characterized in that: 15. At least one of the shape and size of the opening or the dark part corresponding to the signal pattern existing in the macroscopic area is different from the opening or the dark part corresponding to the signal pattern in other parts, respectively. 12. The manufacturing method according to claim 11, wherein the first exposure and the second exposure are performed simultaneously using different photomasks. 16. The method for manufacturing an optical information recording medium according to claim 7, including the step of forming a photosensitive film on one surface of the substrate, and forming an opening or a dark area corresponding to a signal pattern existing in the macroscopic area. , by exposing the photosensitive film to light using a photomask whose shape and/or size are different from those of the openings or dark areas corresponding to the signal pattern of other parts, respectively. A method for manufacturing an optical information recording medium, comprising the step of forming a reflectance changing portion.