JP2006130901A - Manufacturing method for polycarbonate resin sheet having fine protrusion on surface and sheet having fine protrusion on surface - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a melt extrusion method for a polycarbonate resin sheet N having fine protrusions on the surface useful for a sheet for a projection television or the like or for a decorative display panel etc. utilizing a moire phenomenon. <P>SOLUTION: In manufacturing the sheet having fine protrusions on the surface by employing a mirror finish roll as a first roll 2 and a die roll as a second roll 3, setting the second roll on the take-up roll side, holding and pressing a molten-extruded sheet-like polycarbonate resin between these two rolls and taking up the resin, (i) a roll engraved on its surface with fine recesses having a bottom area of 0.00785 to 0.785 mm<SP>2</SP>and the maximum depth of 0.005 to 0.5 mm to the extent ranging 30 to 80% per unit area of 2.54 cm×2.54 cm (1 inch×1 inch) of the roll surface, is used as the die roll, and (ii) the ratio (V<SB>1</SB>/V<SB>2</SB>) of the linear velocity V<SB>1</SB>of the first roll and the linear velocity V<SB>2</SB>of the second roll is set to 0.60 to 0.95. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a polycarbonate resin sheet having a fine convex shape on the surface, and a polycarbonate resin sheet having a fine convex shape on the surface, which are useful for a projection television sheet, a decorative display board using a moire phenomenon, and the like. is there.

  Conventionally, as a sheet for diffusing, condensing or collimating light rays used for applications such as projection televisions, the surface shape of the sheet can be decorated in a bowl shape or a prism shape, etc. Has been done. As the method, a method of heating and pressing a mold having a reverse shape of a shape to be molded on a sheet to the sheet surface or a method of molding with a mold roll when being extruded into a sheet shape is performed. In recent years, there has been a demand for a sheet in which a fine shape is shaped for more precision, and in order to mold such a fine shape, a method of shaping a desired shape by printing on the sheet surface is preferable. It is used.

  For example, Patent Document 1 discloses a decorative body with a point drawing pattern using a moire phenomenon in which a large number of convex condensing elements are printed on a surface in a regular array with a constant fine pitch. A plano-convex lens-shaped condensing element layer formed by arranging a large number of plano-convex lens-shaped condensing elements vertically and horizontally, a transparent substrate layer laminated under the plano-convex lens-shaped condensing element layer, and under the transparent substrate layer There has been proposed a virtual image display decorative body composed of a pixel layer formed by arranging a plurality of stacked pixels having the same shape and the same size in the vertical and horizontal directions.

  However, the plano-convex lens-shaped condensing element layer used for the dot-patterned decorative body and the virtual image displaying decorative body utilizing the moire phenomenon described above is a hemispherical or arc-shaped plano-convex lens shape on the surface of the transparent substrate. Since the light condensing elements are formed in a regular array with a constant fine pitch by printing, this method requires two kinds of materials, a transparent printing ink and a transparent sheet for forming a plano-convex lens-shaped light condensing element layer. Further, since it is necessary to prepare a transparent sheet in advance, the work becomes complicated, and the productivity and economy are inferior.

  In addition, a form in which a transparent plastic film with uneven embossing is superimposed on the upper surface of a mesh pattern print is also used as a decorative display board using the moire phenomenon, so that the moire phenomenon can be clearly seen. It was difficult to stably obtain a polycarbonate resin sheet subjected to fine convex embossing by a melt extrusion method using an engraved mold roll.

Japanese Patent Laid-Open No. 10-35083 JP 2001-55000 A

  A first object of the present invention is to provide a method by which a polycarbonate resin sheet having a fine convex shape on a surface useful for applications such as projection televisions can be easily obtained by a melt extrusion method.

  A second object of the present invention is to provide a method by which a polycarbonate resin sheet having a fine cut spherical convex shape on a surface useful for a decorative display board using a moire phenomenon can be easily obtained by a melt extrusion method. .

  The present inventor has intensively studied a melt extrusion method of a polycarbonate resin sheet having a fine convex shape on the surface. First, a molten polycarbonate resin was extruded from a T-die lip, and when a method of sandwiching a roll with a die roll and a silicon rubber roll with fine concave sculptures on the surface of the roll was tried, the die roll surface of the obtained sheet A fine convex shape was formed at a uniform transfer rate, but the embossed shape of the silicon rubber roll surface was transferred to the back surface, and only a product having no commercial value was obtained.

  Then, instead of a silicon rubber roll, using a mirror surface metal roll, an attempt was made in the same way to perform melt extrusion molding in the same manner, but the shape of the polycarbonate resin sheet with a convex shape extending in the sheet extrusion direction was obtained. For example, in the case of a cut spherical convex shape, only those having an egg-shaped convex shape were obtained, and a polycarbonate resin sheet having a fine desired convex shape could not be stably produced.

  Furthermore, as a result of repeated studies on the melt extrusion method, when sandwiching the melted polycarbonate resin between the mold roll and the mirror surface metal roll, the convex shape can be obtained by controlling the ratio of the respective roll linear velocities to a specific range. The present inventors have found that a polycarbonate resin sheet that is molded into a polycarbonate resin sheet without collapsing and has a fine convex shape on the surface can be stably obtained, and has reached the present invention.

That is, according to the present invention,
1. A mirror surface roll as the first roll and a mold roll as the second roll are arranged, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls to form a sheet In manufacturing a sheet having a fine convex shape on the surface of the sheet, (i) the bottom area of the roll surface is 0.00785 to 0.785 mm ² and the maximum depth is 0.005 to 0.5 mm. (Ii) Line of the first roll, using a roll engraved with a fine concave shape of 30-80% per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface Production of polycarbonate resin sheet having fine convex shape on the surface, characterized in that ratio (V ₁ / V ₂ ) of speed V ₁ and linear velocity V _{2 of} second roll is 0.60 to 0.95 Direction .

2. The mirror roll as the first roll, the mold roll as the second roll and the mirror roll as the third roll are arranged in this order, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll. The sheet is pressed with two rolls, and this sheet is brought into contact with the second roll while being guided to the gap between the second roll and the third roll, and the sheet is peeled from the second roll while passing through the gap. In order to produce a sheet having a fine convex shape on the surface of the sheet by bringing it into contact with the third roll, (i) the bottom area of the roll surface is 0.00785 to 0.785 mm ^{2 as} a mold roll. A fine concave shape having a maximum depth of 0.005 to 0.5 mm is formed in a range of 30 to 80% per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface. In using the engraved roll, to the 0.60 to 0.95 of (ii) the ratio of the linear velocity _{V 1} of the first roll and the linear velocity _{V 2} of the second roll _(V 1 / _{V 2)} A method for producing a polycarbonate resin sheet having a fine convex shape on a characteristic surface.

  3. The fine convex shape has a surface area at the top of the convex portion that is smaller than the bottom area of the bottom surface of the sheet, and is the same or narrower from the bottom surface of the sheet toward the top of the convex portion. A method for producing a polycarbonate resin sheet having a fine convex shape.

  4). The fine convex shape is a group consisting of a cut spherical convex shape, a conical convex shape, a cut conical convex shape, a triangular pyramidal convex shape, a cut triangular pyramidal convex shape, a quadrangular pyramidal convex shape, a cut quadrangular pyramidal convex shape or a kamaboko convex shape. 3. A method for producing a polycarbonate resin sheet having a fine convex shape on the surface according to item 1 or 2, which is at least one selected shape.

5. One surface of a polycarbonate resin sheet having a thickness of 0.5 to 3.0 mm has a fine convex shape with a bottom area of 0.00785 to 0.785 mm ² and a maximum height of 0.005 to 0.5 mm. The shape of the same shape is regularly arranged, and the occupation area ratio of the convex shape to the sheet surface is 30 to 80%. The convex shape and the other portion are made of the same resin and have a fine convex shape. A polycarbonate resin sheet.

6). A mirror surface roll as the first roll and a mold roll as the second roll are arranged, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls to form a sheet In producing a sheet having a fine cut spherical convex shape on the surface of the sheet, (i) a roll having a diameter of 0.1 to 1 mm on the roll surface and a depth of 1/20 to 1/2 of the diameter, pitch using rolls engraved 1.01 to 1.25 times the cutting sphere concave diameter, (ii) the ratio of the linear velocity _{V 1} of the first roll and the linear velocity _{V 2} of the second roll (V ₁ / V ₂ ) is 0.60 to 0.95, a method for producing a polycarbonate resin sheet having a fine cut spherical convex shape on the surface.

7). The mirror roll as the first roll, the mold roll as the second roll and the mirror roll as the third roll are arranged in this order, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll. The sheet is pressed with two rolls, and this sheet is brought into contact with the second roll while being guided to the gap between the second roll and the third roll, and the sheet is peeled from the second roll while passing through the gap. In manufacturing a sheet having a fine cut spherical convex shape, the sheet surface is brought into contact with a third roll, and (i) a roll having a diameter of 0.1 to 1 mm on the roll surface and a depth. Is a roll engraved with a cut spherical concave shape having a diameter of 1/20 to 1/2 and a pitch of 1.01 to 1.25 times the diameter, and (ii) the linear velocity V ₁ of the first roll and the second Roll linear velocity V _{2. A} method for producing a polycarbonate resin sheet having a fine cut spherical convex shape on a surface, wherein a ratio (V ₁ / V ₂ ) to ₂ is 0.60 to 0.95.

  8). 8. The polycarbonate resin having a fine convex shape on the surface thereof according to any one of the preceding items 1, 2, 6 or 7, wherein the holding angle (θ) of the melt-extruded polycarbonate resin with respect to the second roll is in the range of 90 ° to 225 °. Sheet manufacturing method.

  9. The preceding item 1, 2, 6, or 7 in which the linear pressure when the sheet-like polycarbonate resin is sandwiched between the first roll and the second roll and pressed by the two rolls is in the range of 4 to 8 MPa · cm. The manufacturing method of the polycarbonate resin sheet in any one of.

  10. When the glass transition temperature of the polycarbonate resin to be used is Tg, the roll temperature of the first roll is adjusted to a range of Tg-50 to Tg-20 ° C, and the roll temperature of the second roll is adjusted to a range of Tg-90 to Tg-15 ° C. 8. The method for producing a polycarbonate resin sheet according to any one of the preceding items 1, 2, 6 or 7.

  11 8. The method for producing a polycarbonate resin sheet according to any one of the preceding items 1, 2, 6 or 7, wherein the thickness of the sheet is 0.5 to 3.0 mm.

  12 On one surface of a polycarbonate resin sheet having a thickness of 0.5 to 3.0 mm, the diameter is 0.1 to 1 mm, the height is 1/20 to 1/2 of the diameter, and the pitch is 1.01 to 1.25 times the diameter. The cut spherical convex shape has a fine cut spherical convex shape, and the substantially same cut spherical convex shape is regularly arranged, and the occupation area ratio of the cut spherical convex shape to the sheet surface is 50 to 80%. A polycarbonate resin sheet having a fine cut spherical convex shape on the surface of which the shape and other portions are made of the same resin.

13. 13. The polycarbonate resin sheet according to 5 or 12 above, which is formed by a melt extrusion method using a die roll.
Is provided.

Hereinafter, the present invention will be described in detail.
(Manufacture of polycarbonate resin sheet with fine convex shape on the surface)
The polycarbonate resin used in the present invention is obtained, for example, by reacting a dihydric phenol and a carbonate precursor by an interfacial polymerization method or a melting method. Representative examples of the dihydric phenol include 2,2-bis (4-hydroxyphenyl) propane [commonly known as bisphenol A], 1,1-bis (4-hydroxyphenyl) ethane, and 1,1-bis (4-hydroxy). Phenyl) cyclohexane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis (4-Hydroxyphenyl) sulfone and the like can be mentioned, and among them, bisphenol A is preferable. These dihydric phenols can be used alone or in admixture of two or more.

  As the carbonate precursor, carbonyl halide, carbonate ester, haloformate or the like is used, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like.

  In producing the polycarbonate resin by reacting the dihydric phenol and the carbonate precursor by an interfacial polymerization method or a melting method, a molecular weight adjusting agent, a catalyst, or the like can be used as necessary. Furthermore, the polycarbonate resin may contain additives such as mold release agents such as polyhydric alcohol and fatty acid esters or partial esters, heat stabilizers such as phosphite esters, phosphate esters, phosphonate esters, benzophenone series In addition, ultraviolet absorbers such as benzotriazole and benzoxazine, antistatic agents, colorants, brighteners, flame retardants, and the like may be blended. The polycarbonate resin may be a branched polycarbonate resin copolymerized with a trifunctional or higher polyfunctional aromatic compound, or may be a polyester carbonate resin copolymerized with an aromatic or aliphatic difunctional carboxylic acid, Moreover, the mixture which mixed 2 or more types of the obtained polycarbonate resin may be sufficient.

The molecular weight of the polycarbonate resin is preferably 10,000 to 100,000, more preferably 15,000 to 35,000 in terms of viscosity average molecular weight (M). A polycarbonate resin having such a viscosity average molecular weight is preferable because sufficient strength is obtained and the melt fluidity during molding is good. The viscosity average molecular weight referred to in the present invention is obtained by inserting the specific viscosity (η _sp ) obtained from a solution obtained by dissolving 0.7 g of a polycarbonate resin in 100 mL of methylene chloride at 20 ° C. into the following equation.
η _sp /c=[η]+0.45×[η] ² c (where [η] is the intrinsic viscosity)
[Η] = 1.23 × 10 ⁻⁴ M ^0.83
c = 0.7

  The manufacturing method of a polycarbonate resin sheet having a fine convex shape on the surface targeted by the present invention is a sheet obtained by extruding a molten polycarbonate resin from a die of a melt extruder into a sheet shape, sandwiched and pressed by a plurality of cooling rolls. Is a melt extrusion method. At least two cooling rolls are used, usually 2-4.

  In the arrangement of the cooling roll in the present invention, a mirror roll and a mold roll are arranged as the first roll and the second roll, respectively. When the film is wound around the second roll surface, it is more preferable to form a fine convex shape.

  Further, in the arrangement of the cooling roll in the present invention, it is particularly preferable to arrange the mirror roll as the first roll, the mold roll as the second roll, and the mirror roll as the third roll in this order. When the film is wound around the second roll surface, the sheet is peeled from the second roll while passing through the gap with the third roll, and then brought into contact with the third roll, and then the sheet is fed out to form a fine convex shape. Molding is sufficient and more preferable.

  FIG. 1 is a schematic view showing an example of a sheet manufacturing apparatus suitable for carrying out the manufacturing method of the present invention, in which 1 is a T die, 2 is a first cooling roll, 3 is a second cooling roll, 4 Is a third cooling roll, and 5 is a take-up roll.

As the die roll used in the present invention, a roll engraved with a fine concave shape having a bottom area of 0.00785 to 0.785 mm ² and a maximum depth of 0.005 to 0.5 mm is used on the roll surface.

Concave bottom area which is engraved on the roll surface is 0.00785~0.785mm ^2, preferably 0.01~0.7mm ^2, 0.05~0.5mm ² is more preferable. The maximum depth of the concave shape engraved on the roll surface is 0.005 to 0.5 mm, preferably 0.01 to 0.4 mm, and more preferably 0.05 to 0.3 mm. It is preferable that the bottom area and the maximum depth of the concave shape engraved on the roll surface are in the above-mentioned range because the engraved concave shape is almost completely stably transferred to the sheet surface by the manufacturing method of the present invention.

  Further, the ratio of the concave-shaped engraving portion (the area of the roll surface portion) to the roll surface area is 30 to 30 per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface. The range is preferably 80%, more preferably 40 to 75%, and still more preferably 50 to 70%. It is preferable that the ratio of the concave-shaped engraving portion engraved on the roll surface is in the above range because the engraved concave shape is almost completely stably transferred to the sheet surface by the manufacturing method of the present invention.

  In the method for producing a polycarbonate resin sheet having a fine convex shape according to the present invention, a melt-extruded sheet-like polycarbonate resin is sandwiched between the first roll (mirror surface roll) and the second roll (molded roll). In this method, the sheet is pressed while being pressed by the two rolls and, if desired, the sheet is brought into contact with a third roll (mirror roll).

In that case, the ratio of the linear velocity of a 1st roll (mirror surface roll) and a 2nd roll (roll with a type | mold) is important, and the ratio of the linear velocity V1 of a _1st roll, and the linear velocity V2 of a _2nd roll. (V ₁ / V ₂ ) needs to be 0.60 to 0.95, preferably 0.70 to 0.90. When the linear velocity ratio deviates from the above range, the transfer to the concave sheet engraved on the second roll (molded roll) is not sufficient, and the convex shape formed on the sheet collapses, and the sheet is pushed in the extrusion direction. A polycarbonate resin sheet having a uniform and fine convex shape such as an elongated convex shape is not obtained, which is not preferable.

By the first roll ratio of the linear velocity _{V 2} of the linear velocity _{V 1} and the second roll (mirror roll) (typed rolls) _(V 1 / _{V 2)} in the range of 0.60 to 0.95 Since the length of contact of the second roll (molded roll) in the rotational direction is longer than the unit length of the first roll (specular roll) in the rotational direction, transfer to the engraved concave sheet It is considered that the concave shape which is improved completely and is almost completely engraved is transferred to the sheet.

On the other hand, when the linear velocity ratio (V ₁ / V ₂ ) exceeds 0.95, the second roll (molded roll) rotates with respect to the unit length in the rotation direction of the first roll (specular roll). Because the contact length in the direction is almost the same or shorter, the transfer to the engraved concave sheet becomes insufficient, and the convex shape transferred to the sheet becomes a convex shape extended in the sheet extrusion direction It is considered to be.

When the linear velocity ratio (V ₁ / V ₂ ) is less than 0.60, the second roll (molded roll) rotates with respect to the unit length in the rotational direction of the first roll (mirror roll). Although the contact length in the direction is further increased, the linear velocity on the mirror roll side is considerably slower than the linear velocity of the mold roll, so that the scratch side is generated on the mirror surface side of the melt-extruded polycarbonate resin sheet, This is not preferable because the appearance is impaired.

As described above, the first roll the ratio between the linear velocity _{V 2} of the linear velocity _{V 1} and the second roll (mirror roll) (typed rolls) _(V 1 / _{V 2)} from 0.60 to 0.95 By setting the range, the reverse shape of the concave shape engraved on the die roll can be almost completely transferred to the sheet, and a polycarbonate resin sheet having a fine convex shape can be obtained. The preferred shape that can transfer the inverted shape of the concave shape engraved on the roll with mold almost completely to the sheet is based on the convex shape of the polycarbonate resin sheet. Is preferably the same or narrower from the bottom of the sheet toward the top of the convex portion. The top of the convex portion may be a point or a surface. Specific convex shapes include a cut spherical convex shape, a conical convex shape, a cut conical convex shape, a triangular pyramidal convex shape, a cut triangular pyramidal convex shape, a quadrangular pyramidal convex shape, a cut quadrangular pyramidal convex shape, or a kamaboko convex shape. At least one shape selected from the group is preferable, and a cut spherical convex shape is particularly preferable.

  The roll diameters of the first roll, the second roll and the third roll used here are not particularly limited, and it is not necessary to unify them into the same roll diameter, but the roll diameter is usually 200 mm or more, particularly 250 to 500 mm. Those having the same diameter are preferably used.

  In the method for producing a polycarbonate resin sheet having a fine convex shape, a position in which the melt-extruded sheet-like polycarbonate resin is sandwiched between the first roll and the second roll and pressed by the two rolls, That is, when the roll is viewed from the side with respect to the extrusion direction, the contact point between the second roll and a line connecting the center of the circle of the second roll and the center of the circle of the first roll is X (point X in FIG. 8). When the point at which the extruded resin leaves the mold roll as the second roll is Y (point Y in FIG. 8), the angle from X to Y with respect to the center of the second roll (that is, the resin on the second roll) If the holding angle (angle θ in FIG. 8) is defined as the holding angle (angle θ in FIG. 8), the holding angle at which the extruded resin contacts the die roll is important, and the angle θ is in the range of 90 ° to 225 °. It is preferable that 135 ° A range of 180 ° is more preferable.

By setting the holding angle within the above range, the transferability of the sheet to the engraved concave shape is improved, and it is considered that the almost completely engraved concave shape is transferred to the sheet.
When the holding angle θ is 90 ° or more, the length of contact of the second roll (roll with mold) in the rotation direction is long, and transfer onto the engraved concave sheet is sufficient, and the convex shape on the sheet is easy. It is preferably transferred. When the holding angle θ is 225 ° or less, the length of contact of the second roll (molded roll) in the rotational direction is sufficient with respect to the unit length of the first roll (mirror roll) in the rotational direction, and extrusion is performed. The produced sheet is easy to pick up and is preferable for production.

  In the above production method, the linear pressure when the sheet-like polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls is preferably in the range of 4 to 8 MPa · cm. More preferably, it is in the range of 5-7 MPa · cm. By pressing the sheet with a pressure in this range, the concave shape engraved on the die roll is sufficiently transferred.

  Moreover, it is not necessary to press when pulling the polycarbonate resin sheet in contact with the third roll. When pressing between the second roll and the third roll, the linear pressure is preferably in the range of up to 1 MPa · cm.

  In the said manufacturing method, when the glass transition temperature of the polycarbonate resin to be used is set to Tg, it is preferable to adjust the roll temperature of a 1st roll in the range of Tg-50-Tg-20 degreeC, Tg-45-Tg-25. It is more preferable to adjust to the range of ° C. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the first roll is preferably adjusted to a range of 95 to 125 ° C, and more preferably adjusted to a range of 100 to 120 ° C. By adjusting the roll temperature of the first roll to such a temperature range, a sheet having a uniform surface shape on the mirror surface side with little thickness unevenness can be obtained.

  It is preferable to adjust the roll temperature of a 2nd roll to the range of Tg-90-Tg-15 degreeC, and it is more preferable to adjust to the range of Tg-85-Tg-20 degreeC. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the second roll is preferably adjusted to a range of 55 to 130 ° C, more preferably adjusted to a range of 60 to 125 ° C. Note that the roll temperature of the second roll is desirably adjusted by the thickness of the sheet. In order to fully transfer the concave shape engraved on the roll with mold to the sheet, it is preferable to adjust the roll temperature higher because the resin is easily cooled if the sheet is thin, and the sheet is thick In order to reduce the fluidity of the resin, it is preferable to adjust the roll temperature to be low. Specifically, when the sheet thickness is 0.5 to 0.8 mm, the roll temperature is preferably adjusted to a range of Tg-50 to Tg-15 ° C., and when the sheet thickness is 0.8 to 3 mm, the roll is adjusted. It is preferable to adjust the temperature in the range of Tg-90 to Tg-50 ° C.

  The roll temperature of the third roll is preferably adjusted to a range of Tg-25 to Tg ° C, and more preferably adjusted to a range of Tg-20 to Tg-5 ° C. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the third roll is preferably adjusted to a range of 120 to 145 ° C, and more preferably adjusted to a range of 125 to 140 ° C.

  When the roll temperatures of the first roll, the second roll, and the third roll satisfy the above range, the concave shape engraved on the die roll is sufficiently transferred to the sheet, and the convex shape does not lose its shape. Since cooling is performed, it is preferable.

  The polycarbonate resin sheet having a fine convex shape obtained by the production method of the present invention preferably has a thickness (excluding the height of the convex portion) of 0.5 to 3.0 mm, more preferably 0.5. ~ 2.0 mm.

Moreover, the polycarbonate resin sheet obtained by the manufacturing method of the present invention has a fine convex shape with a bottom area of 0.00785 to 0.785 mm ² and a maximum height of 0.005 to 0.5 mm on one surface of the sheet. It is a polycarbonate resin sheet. In addition, the said convex shape has the same shape substantially regularly arranged. The meaning of “substantially the same shape” means that all the concave shapes engraved on the surface of the mold roll to be used have the same shape. Moreover, the polycarbonate resin sheet of this invention is a sheet | seat which a convex shape part and other parts consist of the same resin (polycarbonate resin).

Bottom area of the convex shape of the obtained polycarbonate resin sheet is 0.00785~0.785mm ^2, preferably 0.01~0.7mm ^2, 0.05~0.5mm ² is more preferable. The maximum height of the convex shape is 0.005 to 0.5 mm, preferably 0.01 to 0.4 mm, and more preferably 0.05 to 0.3 mm. A sheet having such a convex shape is preferable because it can be produced with good transferability by the production method of the present invention.

  Further, the area ratio occupied by the convex portion (area cut horizontally in the plane portion of the sheet) with respect to the sheet surface is 30 to 30 per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} on the sheet surface. The range is preferably 80%, more preferably 40 to 75%, and still more preferably 50 to 70%. A sheet having an area ratio occupied by such convex portions is preferable because it can be produced with good transferability by the production method of the present invention.

  The convex shape of the polycarbonate resin sheet is preferably a shape in which the area of the top of the convex portion is smaller than the bottom area of the bottom surface portion of the sheet and becomes the same or narrower from the bottom surface of the sheet toward the top of the convex portion. The top of the convex portion may be a point or a surface. Specific convex shapes include a cut spherical convex shape, a conical convex shape, a cut conical convex shape, a triangular pyramidal convex shape, a cut triangular pyramidal convex shape, a quadrangular pyramidal convex shape, a cut quadrangular pyramidal convex shape, or a kamaboko convex shape. At least one shape selected from the group is preferable, and a cut spherical convex shape is particularly preferable.

  The polycarbonate resin sheet having a fine convex shape of the present invention is used for applications such as projection televisions, taking advantage of its optical characteristics, for diffusing, condensing, and making parallel rays. Suitable as a sheet.

(Manufacture of polycarbonate resin sheet with fine cut spherical convex shape on the surface)
The manufacturing method of a polycarbonate resin sheet having a fine cut spherical convex shape on the surface to be used in the present invention is a method of extruding a molten polycarbonate resin from a die of a melt extruder into a sheet shape, and sandwiching and pressing with a plurality of cooling rolls. This is a melt-extrusion method for pulling out the obtained sheet. At least two cooling rolls are used, usually 2-4.

  In the arrangement of the cooling roll in the present invention, a mirror roll and a mold roll are arranged as the first roll and the second roll, respectively. When the film is wound around the second roll surface, it is more preferable to form a fine cut spherical convex shape.

  Further, in the arrangement of the cooling roll in the present invention, it is particularly preferable to arrange the mirror roll as the first roll, the mold roll as the second roll, and the mirror roll as the third roll in this order. When the film is wound around the second roll surface, the sheet is peeled off from the second roll while passing through the gap with the third roll, and then brought into contact with the third roll to send out the sheet. The shape shaping is sufficient, which is more preferable.

  FIG. 1 is a schematic view showing an example of a sheet manufacturing apparatus suitable for carrying out the manufacturing method of the present invention, in which 1 is a T die, 2 is a first cooling roll, 3 is a second cooling roll, 4 Is a third cooling roll, and 5 is a take-up roll.

  The die roll used in the present invention is a cut sphere having a diameter of 0.1 to 1 mm on the roll surface, a depth of 1/20 to 1/2 of the diameter, and a pitch of 1.01 to 1.25 times the diameter. Use a roll engraved with a concave shape. Here, the concave shape of the cut sphere means a shape obtained by horizontally cutting the sphere at half or from the upper half.

  The diameter of the cut spherical concave shape engraved on the roll surface is 0.1 to 1 mm, preferably 0.2 to 0.8 mm, and more preferably 0.3 to 0.7 mm. If the diameter is smaller than 0.1 mm or larger than 1 mm, it is difficult to visually recognize the moire phenomenon when the obtained sheet is used as a decorative body of a dot drawing pattern or a virtual image display decorative body, and the screen image is not clear. It is not preferable.

  The depth of the cut spherical concave shape engraved on the roll surface is in the range of 1/20 to 1/2 of the diameter, preferably in the range of 1/15 to 1/2, more preferably in the range of 1/10 to 1/2. preferable. When the depth is outside the range of 1/20 to 1/2 of the diameter, it is difficult to obtain a sheet having a fine cut spherical convex shape, which is not preferable.

  Further, in order to cause the obtained sheet to exhibit a moire phenomenon as a decorative body with a dot drawing pattern or a virtual image appearing decorative body, it is necessary to regularly arrange sculptures having a cut spherical shape at a constant pitch on the roll surface. . The arrangement is determined in the range of a pitch angle of 0 to 45 °, and an angle of 45 ° is preferable because a moire phenomenon is easily generated. The pitch means the sum of the minimum interval between an arbitrary cut spherical concave shape and the adjacent cut spherical concave shape and the diameter of the cut spherical concave shape. The pitch of the cut spherical shape engraved on the roll surface is in the range of 1.01 to 1.25 times the diameter, preferably in the range of 1.01 to 1.2 times, and in the range of 1.01 to 1.15 times. Is more preferable. If the pitch is too small, transfer of the cut spherical concave shape is difficult, and if the pitch is too large, transfer of the cut spherical concave shape is good, but the pitch is too large to cause the moire phenomenon, which is not preferable.

  Further, the ratio of the cut spherical concave sculpture portion (the area of the roll surface portion) to the roll surface area is per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface. The range is preferably 50 to 80%, more preferably 55 to 75%, and still more preferably 60 to 70%. When the proportion of the cut spherical concave sculpture is less than 50% or more than 80%, it is difficult to visually recognize the moire phenomenon in order to use the obtained sheet as a dot-drawn pattern decoration or a virtual image display decoration. Is not clear.

  In the method for producing a polycarbonate resin sheet having a fine cut spherical convex shape of the present invention, a melt-extruded sheet-like polycarbonate resin is interposed between the first roll (mirror surface roll) and the second roll (molded roll). And is pressed by the two rolls, and the sheet is pulled out while contacting the sheet with a third roll (mirror surface roll) if desired.

In that case, the ratio of the linear velocity of a 1st roll (mirror surface roll) and a 2nd roll (roll with a type | mold) is important, and the ratio of the linear velocity V1 of a _1st roll, and the linear velocity V2 of a _2nd roll. (V ₁ / V ₂ ) needs to be 0.60 to 0.95, preferably 0.70 to 0.90. When the linear velocity ratio deviates from the above range, the transfer to the cut spherical concave sheet engraved on the second roll (molded roll) is not sufficient, and the convex cut spherical shape formed on the sheet collapses. A polycarbonate resin sheet having a uniform and fine cut spherical convex shape, such as an egg-shaped convex shape as stretched in the extrusion direction, is not preferable.

By the first roll ratio of the linear velocity _{V 2} of the linear velocity _{V 1} and the second roll (mirror roll) (typed rolls) _(V 1 / _{V 2)} in the range of 0.60 to 0.95 The length of contact of the second roll (molded roll) in the rotational direction with respect to the unit length in the rotational direction of the first roll (mirror surface roll) becomes longer, so that the engraved cut spherical concave sheet Therefore, it is considered that the cut spherical concave shape almost completely engraved is transferred to the sheet.

On the other hand, when the linear velocity ratio (V ₁ / V ₂ ) exceeds 0.95, the second roll (molded roll) rotates with respect to the unit length in the rotation direction of the first roll (specular roll). Because the contact length in the direction is almost the same or shorter, the transfer to the engraved cut spherical concave sheet becomes insufficient, and the convex shape transferred to the sheet is stretched in the sheet extrusion direction It is thought that it becomes a convex shape.

When the linear velocity ratio (V ₁ / V ₂ ) is less than 0.60, the second roll (molded roll) rotates with respect to the unit length in the rotational direction of the first roll (mirror roll). Although the contact length in the direction is further increased, the linear velocity on the mirror roll side is considerably slower than the linear velocity of the mold roll, so that the scratch side is generated on the mirror surface side of the melt-extruded polycarbonate resin sheet, This is not preferable because the appearance is impaired.

  The roll diameters of the first roll, the second roll and the third roll used here are not particularly limited, and it is not necessary to unify them into the same roll diameter, but the roll diameter is usually 200 mm or more, particularly 250 to 500 mm. Those having the same diameter are preferably used.

  In the method for producing a polycarbonate resin sheet having a fine cut spherical convex shape, a melt-extruded sheet-like polycarbonate resin is sandwiched between a first roll and a second roll and pressed by the two rolls. The position, that is, the contact point between the second roll and the line connecting the center of the circle of the second roll and the center of the circle of the first roll when the roll is viewed from the side with respect to the extrusion direction is X (point X in FIG. 8). Assuming that the point at which the extruded resin is separated from the mold roll as the second roll is Y (point Y in FIG. 8), the angle from X to Y with respect to the center of the second roll (ie, the second roll) If the holding angle (angle θ in FIG. 8) is defined as the holding angle (the angle during which the resin is in contact), the holding angle at which the extruded resin contacts the die roll is important, and the angle θ is 90 ° to 225 °. Is preferably in the range of 1 5 ° and more preferably in the range of to 180 °.

By setting the holding angle within the above range, the transferability of the sheet to the engraved concave shape is improved, and it is considered that the almost completely engraved concave shape is transferred to the sheet.
When the holding angle θ is 90 ° or more, the length of contact of the second roll (molded roll) in the rotation direction is long, and the transfer to the engraved concave sheet is sufficient, and the sheet has a convex cut spherical shape. It is easily transferred and preferable. When the holding angle θ is 225 ° or less, the length of contact of the second roll (molded roll) in the rotational direction is sufficient with respect to the unit length of the first roll (mirror roll) in the rotational direction, and extrusion is performed. The produced sheet is easy to pick up and is preferable for production.

  In the above production method, the linear pressure when the sheet-like polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls is preferably in the range of 4 to 8 MPa · cm. More preferably, it is in the range of 5-7 MPa · cm. By pressing the sheet with a pressure in this range, the cut spherical concave shape engraved on the die roll is sufficiently transferred.

  Moreover, it is not necessary to press when pulling the polycarbonate resin sheet in contact with the third roll. When pressing between the second roll and the third roll, the linear pressure is preferably in the range of up to 1 MPa · cm.

  In the said manufacturing method, when the glass transition temperature of the polycarbonate resin to be used is set to Tg, it is preferable to adjust the roll temperature of a 1st roll in the range of Tg-50-Tg-20 degreeC, Tg-45-Tg-25. It is more preferable to adjust to the range of ° C. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the first roll is preferably adjusted to a range of 95 to 125 ° C, and more preferably adjusted to a range of 100 to 120 ° C. By adjusting the roll temperature of the first roll to such a temperature range, a sheet having a uniform surface shape on the mirror surface side with little thickness unevenness can be obtained.

  It is preferable to adjust the roll temperature of a 2nd roll to the range of Tg-90-Tg-15 degreeC, and it is more preferable to adjust to the range of Tg-85-Tg-20 degreeC. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the second roll is preferably adjusted to a range of 55 to 130 ° C, more preferably adjusted to a range of 60 to 125 ° C. Note that the roll temperature of the second roll is desirably adjusted by the thickness of the sheet. In order to sufficiently transfer the cut spherical concave shape engraved on the roll with mold to the sheet, it is preferable to adjust the roll temperature to be higher because the resin is easily cooled when the thickness of the sheet is thin. When it is thick, it is preferable to adjust the roll temperature lower in order to reduce the fluidity of the resin. Specifically, when the sheet thickness is 0.5 to 0.8 mm, the roll temperature is preferably adjusted to a range of Tg-50 to Tg-15 ° C., and when the sheet thickness is 0.8 to 3 mm, the roll is adjusted. It is preferable to adjust the temperature in the range of Tg-90 to Tg-50 ° C.

  The roll temperature of the third roll is preferably adjusted to a range of Tg-25 to Tg ° C, and more preferably adjusted to a range of Tg-20 to Tg-5 ° C. When the polycarbonate resin to be used is a polycarbonate resin obtained from bisphenol A, the roll temperature of the third roll is preferably adjusted to a range of 120 to 145 ° C, and more preferably adjusted to a range of 125 to 140 ° C.

  When the roll temperatures of the first roll, the second roll, and the third roll satisfy the above range, the cut spherical concave shape engraved on the die roll is sufficiently transferred to the sheet and the cut spherical convex shape is deformed. Therefore, the sheet is preferably cooled.

  The polycarbonate resin sheet having a fine cut spherical convex shape obtained by the production method of the present invention preferably has a thickness (excluding the height of the cut spherical convex portion) of 0.5 to 3.0 mm, more preferably. Is 0.5 to 2.0 mm. When the thickness of the sheet is less than 0.5 mm, the sheet is easily curled because the thickness is thin, and when the thickness exceeds 3.0 mm, the occurrence of the moire phenomenon is reduced.

  The polycarbonate resin sheet obtained by the production method of the present invention has a diameter of 0.1 to 1 mm, a height of 1/20 to 1/2 of the diameter, and a pitch of 1.01 to 1. It is a polycarbonate resin sheet having a 25-fold cut spherical convex shape. Here, the convex shape of the cut sphere means a shape obtained by horizontally cutting the sphere at half or from the upper half. Specifically, the shape 8 shown in FIG. In addition, this cut spherical convex shape is arranged in substantially the same shape. The meaning of “substantially the same shape” means that all the cut spherical concave shapes engraved on the surface of the mold roll to be used have the same shape. Moreover, the polycarbonate resin sheet of this invention is a sheet | seat which a convex shape part and other parts consist of the same resin (polycarbonate resin).

  The cut spherical convex shape has a diameter of 0.1 to 1 mm, preferably 0.2 to 0.8 mm, and more preferably 0.3 to 0.7 mm. Specifically, the width is 10 shown in FIG. When the diameter is smaller than 0.1 mm or larger than 1 mm, it is difficult to visually recognize the moire phenomenon and the screen image becomes unclear when this sheet is used as a dot-drawing pattern decoration or a virtual image display decoration.

  The height of the cut spherical convex shape is in the range of 1/20 to 1/2 of the diameter, preferably in the range of 1/15 to 1/2, and more preferably in the range of 1/10 to 1/2. A sheet having a convex cut spherical shape whose height is outside the range of 1/20 to 1/2 of the diameter is not preferable because it is difficult to manufacture.

  Further, in order to develop a moire phenomenon as a decorative body with a dot drawing pattern or a virtual image appearing decorative body on the sheet, it is necessary to regularly arrange the convex shapes of the cut spheres at a constant pitch. The arrangement is determined in the range of an angle in the pitch direction of 0 to 45 °, and an angle of 45 ° is particularly preferable because the moire phenomenon is easily generated. Note that the pitch means the sum of a minimum interval between an arbitrary cut spherical convex shape and a neighboring cut spherical convex shape and a diameter of the cut spherical convex shape. Specifically, the width is 9 shown in FIG. The pitch of the cut spherical convex shape is in the range of 1.01 to 1.25 times the diameter, preferably in the range of 1.01 to 1.2 times, and more preferably in the range of 1.01 to 1.15 times. If the pitch is too small, it is difficult to manufacture the sheet, and if the pitch is too large, the moiré phenomenon is less likely to occur, which is not preferable.

  In addition, the area ratio of the cut spherical convex portion (area cut horizontally in the plane portion of the sheet) to the sheet surface is per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} on the sheet surface. The range is preferably 50 to 80%, more preferably 55 to 75%, and still more preferably 60 to 70%. When the proportion of the cut spherical convex portion is less than 50% or more than 80%, it is difficult to visually recognize the moire phenomenon when using the sheet as a decorative body of a dot drawing pattern or a virtual image display decorative body, and the screen image is clear. Not.

  The polycarbonate resin sheet having a fine cut spherical convex shape of the present invention is suitable for use as a decorative body of a point drawing pattern utilizing the moire phenomenon and a virtual image display decorative body utilizing an optical illusion.

  According to the method for producing a polycarbonate resin sheet of the present invention, a polycarbonate resin sheet having a desired fine convex shape is stably provided, and the sheet is used for a projection television or the like by taking advantage of its optical characteristics. Therefore, it is suitable for use as a decorative body with a point drawing pattern using a moire phenomenon or a virtual image display decorative body using an optical illusion, and the industrial effect produced is particularly remarkable.

  The following examples further illustrate the present invention. In addition, the part in an Example means a weight part. The evaluation of characteristics is as follows.

(1) Diameter and pitch of cut spherical convex portion of sheet The obtained sheet was observed with a microscope from directly above, and the diameter and pitch of the cut spherical convex portion were measured.

(2) Height of cut spherical convex portion of sheet The obtained sheet was cut perpendicularly to the sheet from the apex of the cut spherical convex portion, and the height from the apex to the sheet plane was measured.

(3) Proportion of cut spherical convex portion The cut spherical convex portion (area cut horizontally in the plane portion of the sheet) per unit area (2.54 cm × 2.54 cm) of the sheet surface (plane) was calculated. .

(4) Three-dimensional effect of image On the back side of the surface of the obtained sheet having the cut spherical convex portion, circular dots having a height of 3 μm and the same diameter and pitch as the cut spherical convex shape are arranged. Printing was performed with the direction angle shifted by 10 °, and the sheet was observed from the vertical direction at a distance of 30 cm. The case where the point drawing pattern was seen as an enlarged image having a three-dimensional effect was marked with ◯, and the case where the point drawing pattern was not seen three-dimensionally was marked with x.

(5) Tg (glass transition temperature)
Using a 2910 type DSC manufactured by TA Instruments Japan Co., Ltd., measurement was performed under a nitrogen stream at a rate of temperature increase of 20 ° C./min.

[Example 1]
Using the apparatus shown in FIG. 1, a polycarbonate resin having a viscosity average molecular weight of 23,900 (Tg; 145 ° C.) produced from bisphenol A and phosgene by an interfacial polymerization method is heated in an extruder with a T die lip having a screw diameter of 120 mm. Continuous extrusion at about 280 ° C. and a width of 1000 mm, the first roll and the third roll are mirror surface metal rolls (both have a roll diameter of 300 mm), and the second roll is a die roll (diameter 490 μm, depth 100 μm cut spherical concave shape) A roll having a diameter of 300 mm engraved at a pitch of 500 μm; see FIG. 2), the temperatures of the first roll and the second roll are set to 115 ° C. and 115 ° C., respectively, and the temperature of the third roll is set to 130 ° C. The ratio of the linear velocity (rotational speed) of the first roll to the roll was set to 0.75, and the extruded molten polycarbonate resin was It is sandwiched between one roll and the second roll, pressed with a linear pressure of 6 MPa · cm, and passed between the second roll and the third roll while making contact with the third roll (holding angle θ = 170 °), a polycarbonate resin sheet was molded, and a sheet (thickness 0.7 mm) having a convex cut spherical convex portion was obtained by a take-up roll (see FIGS. 3 and 4). Table 1 shows the characteristic values of the obtained sheet. Moreover, the microscope picture of the surface shape of the obtained sheet | seat was shown in FIG.

[Example 2]
The cutting sphere is cut in the same manner as in Example 1 except that the temperature of the second roll is set to 70 ° C., the temperature of the third roll is set to 140 ° C., and the ratio of the rotation speed of the first roll to the second roll is set to 0.85. A sheet (thickness 1.0 mm) having a convex portion was obtained. Table 1 shows the characteristic values of the obtained sheet.

[Example 3]
A cut spherical convex portion is formed by the same method as in Example 1 except that a die roll (a roll having a diameter of 490 μm and a cut spherical convex shape having a depth of 200 μm engraved with a pitch of 500 μm) is used as the second roll. A sheet having a thickness of 0.7 mm was obtained. Table 1 shows the characteristic values of the obtained sheet.

[Comparative Example 1]
A sheet (thickness 0) having a cut spherical convex portion by the same method as in Example 1 except that the temperature of the third roll is set to 115 ° C. and the ratio of the rotation speed of the first roll to the second roll is set to 1.0. 0.7 mm). Table 1 shows the characteristic values of the obtained sheet. Moreover, the microscope picture of the surface shape of the obtained sheet | seat was shown in FIG.

It is the schematic which shows an example of the manufacturing apparatus of the polycarbonate resin sheet which has a fine cut spherical convex shape on the surface of this invention. It is an enlarged view which shows an example of the 2nd roll (roll with a type | mold) in FIG. It is an expansion vertical side view of the polycarbonate resin sheet which has a fine cut spherical convex shape on the surface which is one mode of the present invention. It is the figure seen from the upper surface of the polycarbonate resin sheet which has the fine cut spherical convex shape on the surface which is 1 aspect of this invention (In addition, the cut spherical convex part is shown in black for easy understanding.). FIG. 5 is an enlarged view of FIG. 4. It is the microscope picture which copied the polycarbonate resin sheet which has the fine cut spherical convex shape on the surface obtained in Example 1 from diagonally upward (the round part protrudes). It is the microscope picture which copied the polycarbonate resin sheet which has a fine cut spherical convex shape on the surface obtained by comparative example 1 from almost right above (the round part has projected). It is the figure which showed holding angle (theta) with respect to the 2nd roll (roll with a type | mold) of a polycarbonate resin sheet.

Explanation of symbols

1. T dice 2. First roll (mirror roll)
3. Second roll (roll with mold)
4). Third roll (mirror roll)
5. Take-up roll 6. 6. Melt extruded polycarbonate resin sheet 7. A portion where the cut spherical concave shape is engraved on the die roll. 8. A portion having a convex shape of a cut spherical portion of a melt-extruded polycarbonate resin sheet. 9. Pitch of cut spherical convex shape part Diameter X of cut spherical convex portion; contact point Y of second roll of line connecting the center of circle of second roll and center of first roll; extruded resin is second roll (molded roll) Away from the point θ;

Claims (13)

A mirror surface roll as the first roll and a mold roll as the second roll are arranged, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls to form a sheet In manufacturing a sheet having a fine convex shape on the surface of the sheet, (i) the bottom area of the roll surface is 0.00785 to 0.785 mm ² and the maximum depth is 0.005 to 0.5 mm. (Ii) Line of the first roll, using a roll engraved with a fine concave shape of 30-80% per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface Production of polycarbonate resin sheet having fine convex shape on the surface, characterized in that ratio (V ₁ / V ₂ ) of speed V ₁ and linear velocity V _{2 of} second roll is 0.60 to 0.95 Direction . The mirror roll as the first roll, the mold roll as the second roll and the mirror roll as the third roll are arranged in this order, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll. The sheet is pressed with two rolls, and this sheet is brought into contact with the second roll while being guided to the gap between the second roll and the third roll, and the sheet is peeled from the second roll while passing through the gap. In order to produce a sheet having a fine convex shape on the surface of the sheet by bringing it into contact with the third roll, (i) the bottom area of the roll surface is 0.00785 to 0.785 mm ^{2 as} a mold roll. A fine concave shape having a maximum depth of 0.005 to 0.5 mm is formed in a range of 30 to 80% per unit area {2.54 cm × 2.54 cm (1 inch × 1 inch)} of the roll surface. In using the engraved roll, to the 0.60 to 0.95 of (ii) the ratio of the linear velocity _{V 1} of the first roll and the linear velocity _{V 2} of the second roll _(V 1 / _{V 2)} A method for producing a polycarbonate resin sheet having a fine convex shape on a characteristic surface.   3. The surface according to claim 1, wherein the fine convex shape has a shape in which the area of the top of the convex portion is smaller than the bottom area of the bottom surface portion of the sheet, and is the same or narrower from the bottom surface portion of the sheet toward the top of the convex portion. For producing a polycarbonate resin sheet having a fine convex shape.   The fine convex shape is a group consisting of a cut spherical convex shape, a conical convex shape, a cut conical convex shape, a triangular pyramidal convex shape, a cut triangular pyramidal convex shape, a quadrangular pyramidal convex shape, a cut quadrangular pyramidal convex shape or a kamaboko convex shape. The method for producing a polycarbonate resin sheet having fine convex shapes on the surface according to claim 1 or 2, wherein the shape is at least one selected shape. One surface of a polycarbonate resin sheet having a thickness of 0.5 to 3.0 mm has a fine convex shape with a bottom area of 0.00785 to 0.785 mm ² and a maximum height of 0.005 to 0.5 mm. The shape of the same shape is regularly arranged, and the occupation area ratio of the convex shape to the sheet surface is 30 to 80%. The convex shape and the other portion are made of the same resin and have a fine convex shape. A polycarbonate resin sheet. A mirror surface roll as the first roll and a mold roll as the second roll are arranged, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll and pressed with the two rolls to form a sheet In producing a sheet having a fine cut spherical convex shape on the surface of the sheet, (i) a roll having a diameter of 0.1 to 1 mm on the roll surface and a depth of 1/20 to 1/2 of the diameter, pitch using rolls engraved 1.01 to 1.25 times the cutting sphere concave diameter, (ii) the ratio of the linear velocity _{V 1} of the first roll and the linear velocity _{V 2} of the second roll (V ₁ / V ₂ ) is 0.60 to 0.95, a method for producing a polycarbonate resin sheet having a fine cut spherical convex shape on the surface. The mirror roll as the first roll, the mold roll as the second roll and the mirror roll as the third roll are arranged in this order, and the melt-extruded polycarbonate resin is sandwiched between the first roll and the second roll. The sheet is pressed with two rolls, and this sheet is brought into contact with the second roll while being guided to the gap between the second roll and the third roll, and the sheet is peeled from the second roll while passing through the gap. In manufacturing a sheet having a fine cut spherical convex shape, the sheet surface is brought into contact with a third roll, and (i) a roll having a diameter of 0.1 to 1 mm on the roll surface and a depth. Is a roll engraved with a cut spherical concave shape having a diameter of 1/20 to 1/2 and a pitch of 1.01 to 1.25 times the diameter, and (ii) the linear velocity V ₁ of the first roll and the second Roll linear velocity V _{2. A} method for producing a polycarbonate resin sheet having a fine cut spherical convex shape on a surface, wherein a ratio (V ₁ / V ₂ ) to ₂ is 0.60 to 0.95.   The polycarbonate having a fine convex shape on the surface according to any one of claims 1, 2, 6 and 7, wherein a holding angle (θ) of the polycarbonate resin melt-extruded with respect to the second roll is in a range of 90 ° to 225 °. Manufacturing method of resin sheet.   The linear pressure when the sheet-like polycarbonate resin is sandwiched between the first roll and the second roll and pressed by the two rolls is in the range of 4 to 8 MPa · cm. 8. A method for producing a polycarbonate resin sheet according to any one of 7 above.   When the glass transition temperature of the polycarbonate resin to be used is Tg, the roll temperature of the first roll is adjusted to a range of Tg-50 to Tg-20 ° C, and the roll temperature of the second roll is adjusted to a range of Tg-90 to Tg-15 ° C. The manufacturing method of the polycarbonate resin sheet in any one of Claims 1, 2, 6, or 7.   The method for producing a polycarbonate resin sheet according to claim 1, wherein the sheet has a thickness of 0.5 to 3.0 mm.   On one surface of a polycarbonate resin sheet having a thickness of 0.5 to 3.0 mm, the diameter is 0.1 to 1 mm, the height is 1/20 to 1/2 of the diameter, and the pitch is 1.01 to 1.25 times the diameter. The cut spherical convex shape has a fine cut spherical convex shape, and the substantially same cut spherical convex shape is regularly arranged, and the occupation area ratio of the cut spherical convex shape to the sheet surface is 50 to 80%. A polycarbonate resin sheet having a fine cut spherical convex shape on the surface of which the shape and other portions are made of the same resin.   The polycarbonate resin sheet according to claim 5 or 12 formed by a melt extrusion method using a die roll.

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