JP2022173231A - Method for releasing molded article and apparatus for releasing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for releasing, and an apparatus for releasing capable of taking out a highly accurately molded article from a mold.

SOLUTION: A method for releasing a molded article 2 having a first face 2A formed by curing a curable resin supplied to a molding face 1A of a mold 1, and transferred with a pattern shape of the molding face 1A, and a second face 2B which is a back side thereof from the mold 1 includes: a first process of pasting an adhesive sheet 3 having an adhesive strength of 3 N/20 mm or higher onto the entire second face 2B of the molded article 2; and a second process of releasing the molded article 2 from the mold 1 by relatively moving the adhesive sheet 3 and the mold 1 in a direction to separate the adhesive sheet 3 from the mold 1. Also provided is an apparatus for releasing which performs the method for releasing.

SELECTED DRAWING: Figure 6

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention relates to a method and apparatus for releasing a molded article from a mold. The molding is preferably an imprint molding.

2. Description of the Related Art In recent years, mobile electronic devices such as mobile phones and smart phones are required to have optical components such as sensors and cameras to improve their product value. In addition, the size and thickness of electronic devices are becoming smaller and thinner year by year, and the parts used are also required to be smaller and thinner. Conventionally, such demands have been met by manufacturing parts by injection molding, but the injection molding method has reached its limit in responding to miniaturization and thinning. Therefore, an imprint molding method is attracting attention as a new molding method to replace the injection molding method. However, the imprint molding method tends to cause a problem in releasing the molded product from the mold, which may impair the molding accuracy.

Methods for releasing the molded product from the mold in imprint molding include a method of releasing by inserting a pin between the mold and the molded product (for example, Patent Document 1), and a method of holding the periphery of the molded product vertically. A method of releasing from the mold in the direction (for example, Patent Document 2), a method of holding a part of the molded product and releasing it from the mold in an oblique direction (for example, Patent Documents 3 and 4), vibration and ultrasonic waves to the mold There have been reported a method of assisting release by irradiating (for example, Patent Document 5), a method of releasing from a molded product by tilting the mold (for example, Patent Document 6), and the like.

JP 2007-118552 A JP 2003-181855 A JP 2008-284822 A WO2010/142958 pamphlet JP 2012-254559 A JP 2012-253303 A

In the imprint molding method, a fine pattern is generally formed on the mold, and high molding accuracy is required. In particular, when molding an aggregate of multiple products in a single molding process, such as wafer-level lens arrays, it is necessary to separate the individual products by dicing. are required to have excellent positional accuracy between products. However, in the methods of Patent Documents 1 to 4, an excessive load is applied to a part of the molded product, especially at the start of mold release, so it was found that problems such as warping of the molded product and deterioration of positional accuracy occurred. did. Moreover, when resin or glass is used for the mold, the strength of the mold itself is low, and it has been difficult to adopt the method of applying force from the outside as disclosed in Patent Documents 5 and 6.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a mold release method capable of removing a highly accurate molded product from a mold.
Another object of the present invention is to provide a mold release device capable of removing a highly accurate molded product from a mold.

As a result of intensive studies by the present inventors in order to solve the above problems, when releasing the molded product adhering to the molding surface of the mold from the mold, the entire surface of the molded product that is not attached to the mold can be identified. By affixing an adhesive sheet with an adhesive force of 100% and releasing it from the mold, the load at the time of releasing from the mold is evenly distributed over the entire molded product. I found that it can be extracted. The present invention has been completed based on these findings.

That is, the present invention has a first surface to which the pattern shape of the molding surface is transferred and a second surface on the back side, which is formed by curing a curable material supplied to the molding surface of the mold. Provided is a method for releasing a molded product from the mold, characterized by having the following steps.
First step: Affixing an adhesive sheet having an adhesive force of 3 N/20 mm or more to the entire second surface of the molded product;
Second step: releasing the molded article from the mold by relatively moving the adhesive sheet and the mold in a direction in which the adhesive sheet and the mold are separated from each other.

In the method for releasing a molded product, the molded product is an array having two or more optical elements arranged two-dimensionally on the first surface and having a substrate portion connecting these optical elements to each other. may

In the method for releasing a molded product, it is preferable that at least a flat portion to which the pressure-sensitive adhesive sheet is attached is present on the second surface.

In the method for releasing a molded product, the adhesive sheet may be a laminate in which a base material and an adhesive layer are laminated on one surface of the base material, and the base material may be a resin.

The method for releasing the molded product may further include the following steps.
Third step: peeling off the pressure-sensitive adhesive sheet from the second surface of the molded article obtained in the second step.

The method for releasing the molded product may further include the following steps.
3' step: dicing the molded article obtained in the second step, which has a plurality of optical elements arranged two-dimensionally on the first surface and the second surface is fixed with the adhesive sheet. Then, the optical element is separated into individual pieces to obtain an optical member.

In the method for releasing a molded product, the optical element may be a wafer level lens.

In the method for releasing a molded product, the curable material may be a curable epoxy resin composition.

In the method for releasing a molded product, the material forming the mold may be at least one selected from the group consisting of resin, metal, and glass.

In the mold releasing method, at least part of the patterned area of the molding surface of the mold may be treated with a mold release agent.

In addition, the present invention provides a molding having a first surface to which the pattern of the molding surface is transferred and a second surface on the back side, which is formed by curing a curable material supplied to the molding surface of the mold. An apparatus for releasing an article from said mold, comprising:
an attaching means for attaching an adhesive sheet to the second surface;
moving means for relatively moving the adhesive sheet and the mold;
a sticking control means for controlling the sticking means to stick the adhesive sheet on the entire second surface of the molded product;
a movement control means for controlling the moving means to relatively move the adhesive sheet and the mold in a direction in which the adhesive sheet and the mold are separated from each other. .

Since the mold release method and the mold release device of the present invention have the above-described configuration, the load applied when the molded product is released from the mold is uniformly distributed over the entire molded product. A molded product can be stably removed from the mold.
The mold release method or mold release device of the present invention can be used for a single molding (preferably, imprint molding) for a molded product that is an assembly of a plurality of products. Since it is possible to stably manufacture precision molded products, for example, manufacturing of wafer level lens arrays for efficiently manufacturing sensor lenses and camera lenses for mobile electronic devices such as mobile phones and smartphones. can be suitably applied to

It is a schematic diagram showing an example of a mold. (a) is a perspective view, (b) is a top view, and (c) is a side view. It is a schematic diagram showing an example of a cast. (a) is a perspective view, (b) is a top view, and (c) is a side view. FIG. 4 is a schematic diagram showing an example of a state in which the first surface of the molded article is attached to the molding surface of the mold; (a) is a perspective view, (b) is a top view, and (c) is a side view. It is the schematic which shows an example of an adhesive sheet. (a) is a perspective view, (b) is a top view, (c) is a side view, and (d) is an enlarged view of the side view. It is an explanatory view showing an example of the 1st process of the mold release method of the present invention. (a) is a perspective view, (b) is a top view, and (c) is a side view. It is explanatory drawing which shows an example of the 2nd process of the mold release method of this invention. (a) is a perspective view, and (b) is a side view. It is explanatory drawing which shows another example of the 2nd process of the mold release method of this invention. (a) is a perspective view, and (b) is a side view. FIG. 2 is a schematic diagram showing an example of a molded article having a second surface to which a pressure-sensitive adhesive sheet obtained by the mold release method of the present invention is attached. (a) is a perspective view, (b) is a top view, and (c) is a sectional view taken along line XX'. 1 is a block diagram showing an example of a mold release device of the present invention; FIG. It is a flow chart which shows the flow of an example of the mold release method of the present invention. It is a schematic diagram of a lower mold used in Examples and Comparative Examples. (a) is a top view, and (b) is a cross-sectional view taken along line AA'. FIG. 10 is an explanatory view (cross-sectional view) showing the steps of Manufacturing Example 1;

Exemplary embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto and is merely illustrative.

[Release method of molded product]
The mold release method of the present invention (hereinafter sometimes referred to as "the mold release method of the present invention") is supplied to the molding surface of the mold (hereinafter sometimes referred to as the "mold of the present invention"). A molded article having a first surface to which the pattern shape of the molding surface is transferred and a second surface on the back side (hereinafter referred to as the "molded article of the present invention"), which is formed by curing the curable material. ) from the mold, characterized by comprising the following steps.
First step: Affixing an adhesive sheet having an adhesive force of 3 N/20 mm or more (hereinafter sometimes referred to as "adhesive sheet of the present invention") to the entire second surface of the molded product;
Second step: releasing the molded article from the mold by relatively moving the adhesive sheet and the mold in a direction in which the adhesive sheet and the mold are separated from each other.

[mold]
FIG. 1 shows a schematic diagram of an example of the mold of the present invention. (a) is a perspective view, (b) is a top view, and (c) is a side view.

The mold 1 of the present invention has at least a molding surface 1A having a pattern region 11 (the pattern shape is not shown). The molding surface 1</b>A of the mold 1 of the present invention may have a non-pattern area 12 around the pattern area 11 in addition to the pattern area 11 .

In the mold of the present invention, the pattern region is provided with a reverse concave-convex pattern shape (a reverse shape of the desired molded product) corresponding to the desired shape for giving the molded product a desired shape. The shape of the horizontal surface of the pattern-shaped portion of the mold is not particularly limited, but the aspect ratio is preferably 0.1 to 1, more preferably 0.5 to 1, and the closer to 1, the better. The aspect ratio is the ratio of the length in the vertical direction to the length in the horizontal direction when the longest direction of the shape of the horizontal plane is taken as the horizontal direction. When the aspect ratio is within the above range, the degree of curing tends to be uniform throughout the molded article of the present invention, and positional deviation is less likely to occur before and after curing. As shown in FIG. 1(a), the shape of the horizontal plane is the pattern shape viewed from the upper surface (corresponding to FIG. 1(b)) when the mold is placed horizontally so that the pattern area 11 faces the upper surface. It is the shape of the part.

Materials constituting the mold of the present invention are not particularly limited, but resins, metals, glass, combinations of these materials, and the like can be mentioned.

The resin constituting the mold of the present invention is not particularly limited. selected, for example, silicone-based resin (dimethylpolysiloxane, etc.), fluorine-based resin, polyolefin-based resin (polyethylene, polypropylene, polycyclic olefin, etc.), polyethersulfone-based resin, polycarbonate-based resin, polyester-based resin (polyarylate, polyethylene terephthalate, polyethylene naphthalate, etc.), polyamide resins, polymethyl methacrylate, and the like.

Metals constituting the mold of the present invention are not particularly limited, but are iron, iron alloys (stainless steel, permalloy, etc.), nickel, brass, silicon wafers, copper, copper alloys, gold, silver, cobalt, aluminum, zinc, tin. , tin alloys, titanium, and chromium. When the mold of the present invention is made of metal, the molding surface may be subjected to electroless plating of a metal material such as nickel, plating treatment such as electroforming, or shaping by photolithography.

Resins are preferable as the material constituting the mold of the present invention, and silicone resins are particularly preferable. When a silicone resin is used, compatibility with a curable material containing an epoxy compound and excellent shape accuracy are obtained. In addition, since the releasability of the molded product and the flexibility of the mold are excellent, the molded product can be taken out more easily.

A commercially available product or a manufactured product may be used as the mold of the present invention. When manufacturing the mold of the present invention, for example, it can be manufactured by molding (preferably imprint molding) a resin composition forming the mold, and then thermally curing the resin composition. A mold having a desired concave-convex shape can be used for molding the resin composition, and for example, it can be produced by the following methods (1) and (2).
(1) A method in which a mold is pressed against the coating film of the resin composition applied on the substrate, the coating film of the resin composition is cured, and then the mold is peeled off. (2) The resin composition is applied to the mold. A method in which an object is directly coated, a substrate is adhered from above, the coating film of the resin composition is cured, and the mold is peeled off.

On the molding surface of the mold of the present invention, at least part of the pattern region may be treated with a release agent. As a method of treating the release agent, for example, a method of forming a release film by applying a release agent such as a fluorine-based release agent, a silicone-based release agent, or a wax-based release agent, or a method of forming a release film using a fluororesin, etc. and a method of forming a vapor deposition release film by vacuum vapor deposition. Examples of the method of applying the release agent include a spray coating method, a dip coating method, a spin coating method, and a screen printing method.

The release film may be a single layer or multiple layers. Moreover, when the release film has multiple layers, each layer may be formed of the same component or may be formed of different components. In the present invention, among others, a mold having a release film coated with a fluorine-based release agent on its molding surface is preferable because it has excellent releasability.

[Molded product]
FIG. 2 shows a schematic diagram of an example of the molded product of the present invention. (a) is a perspective view, (b) is a top view, and (c) is a side view.

The molded product 2 of the present invention has a first surface 2A to which the pattern shape 11 of the molding surface 1A of the mold 1 of the present invention is transferred, and a second surface 2B on the back side. The shape of the molded product 2 of the present invention is not particularly limited as long as it has the first surface 2A and the second surface 2B. Substrates with 2B are preferred.

The first surface 2A of the molded product of the present invention has a transfer area 21 (the pattern shape is not shown) having an inverted shape obtained by transferring the pattern shape of the pattern area 11 of the molding surface 1A of the mold of the present invention. The first surface 2</b>A may have a non-transfer area 22 around the transfer area 21 in addition to the transfer area 21 .

The pattern shape formed in the transfer region 21 on the first surface 2A is not particularly limited, but is preferably adapted to high-quality optical members, such as lenses, prisms, LEDs, organic EL elements, semiconductor lasers, transistors, Solar cells, CCD image sensors, optical waveguides, optical fibers, alternative glass (eg, display substrates, hard disk substrates, polarizing films), optical diffraction elements, etc., and lenses that require high precision are particularly preferred.

The type and shape of the lens are not particularly limited, but for example, spectacle lenses, lenses for optical equipment, lenses for optoelectronics, lenses for lasers, lenses for pickups, lenses for in-vehicle cameras, lenses for mobile cameras, lenses for smartphones, lenses for digital Camera lenses, OHP lenses, Fresnel lenses, microlenses, wafer level lenses, etc. can be mentioned, and in particular, it is preferably applied to wafer level lenses that are required to be small, thin and have high precision.

Although the molded product of the present invention is not particularly limited, two or more of the elements (optical elements) of the optical member are two-dimensionally arranged on the first surface, and a substrate portion connecting these optical elements to each other. can be suitably applied to an array (optical element array) having Since the molded product of the present invention has a small warpage of the entire molded product and a high positional accuracy of the molding pattern, when the optical element array is singulated into individual optical elements, a plurality of optical elements with uniform shape accuracy can be obtained. Obtainable. If the optical element array is a wafer level lens array, the lens diameter is, for example, 1-5 mm. Further, the width of the substrate portion is, for example, 1 mm or less, preferably 0.05 to 1 mm, particularly preferably 0.05 to 0.5 mm.

The second surface of the molded product of the present invention is not particularly limited, and may have a pattern shape or may be planar without a pattern shape. In the process, it is preferable to have at least a flat portion to which the adhesive sheet is attached and which is stably fixed to the second surface. The ratio of the area of the flat portion to the total area (100%) of the second surface is not particularly limited, but is preferably 15% or more, more preferably 25% or more, and still more preferably 35% or more. When the area ratio of the flat portion is 15% or more, the second surface can be stably fixed to the pressure-sensitive adhesive sheet of the present invention, and the molded product can be reliably released from the mold. The upper limit of the ratio of the area of the flat portion is not particularly limited, and may be 100%, that is, the entire surface of the second surface may be the flat portion. As shown in FIG. 2(a), the area of the flat portion and the total area of the second surface are the top surface (Fig. 2 It is the area of the projection view of the whole of the plane part and the 2nd surface seen from (b)). Hereinafter, the term "area" in the specification of the present application shall be similarly defined.

When the second surface of the molded product of the present invention has a pattern shape, it is not particularly limited, but preferably does not have a convex portion with respect to the planar portion to which the pressure-sensitive adhesive sheet of the present invention is attached. If the second surface has a convex portion with respect to the flat portion, the pressure-sensitive adhesive sheet of the present invention cannot be sufficiently attached to the flat portion of the second surface, and the molded product may not be released well. be.

When the second surface of the molded product of the present invention has a pattern shape, it is not particularly limited, but it may have recesses with respect to the planar portion to which the pressure-sensitive adhesive sheet of the present invention is attached. At that time, when the molded product of the present invention is an optical element array, the two or more concave portions present on the second surface are arranged at positions corresponding to the two or more optical elements present on the first surface. preferably.

When the second surface of the molded product of the present invention has a concave portion with respect to the flat portion to which the adhesive sheet of the present invention is attached, the area of the concave portion with respect to the entire area (100%) of the second surface 2B Although the ratio is not particularly limited, it is preferably 85% or less, more preferably 75% or less, and still more preferably 65% or less. When the ratio of the area of the recesses is 85% or less, the second surface can be stably fixed to the pressure-sensitive adhesive sheet of the present invention, and the molded product can be reliably released from the mold. The lower limit of the ratio of the area of the recesses to the total area of the second surface is not particularly limited, and the present invention also includes 0%, that is, the case where the second surface has no recesses.

The molded article of the present invention can be formed by supplying a curable material to the molding surface of the mold of the present invention and curing it.

The curable material is not particularly limited, but from the viewpoint of mass production and moldability of the molded product, a resin that cures in a short time and has excellent heat resistance is preferable. curable resin compositions, curable silicone resin compositions, etc., which cure in a short time, have a short casting time in a mold, have a small curing shrinkage rate, are excellent in dimensional stability, and are susceptible to oxygen inhibition during curing. An epoxy cationic curable resin composition (curable epoxy resin composition) is preferred.

As the epoxy resin, known or commonly used compounds having one or more epoxy groups (oxirane ring) in the molecule can be used. Examples include alicyclic epoxy compounds, aromatic epoxy compounds, aliphatic epoxy compounds, and the like. mentioned. In the present invention, among others, in terms of being able to form a cured product having excellent heat resistance and transparency, a multi-polyether having an alicyclic structure and two or more epoxy groups as functional groups in one molecule. Functional cycloaliphatic epoxy compounds are preferred.

Specifically, the polyfunctional alicyclic epoxy compound is
(i) a compound having an epoxy group composed of two adjacent carbon atoms and an oxygen atom constituting an alicyclic ring (that is, an alicyclic epoxy group); (iii) a compound having an alicyclic ring and a glycidyl group, and the like.

Examples of the compound (i) having an alicyclic epoxy group include compounds represented by the following formula (i).

In formula (i) above, X represents a single bond or a linking group (a divalent group having one or more atoms). Examples of the linking group include a divalent hydrocarbon group, an alkenylene group in which part or all of the carbon-carbon double bond is epoxidized, a carbonyl group, an ether bond, an ester bond, a carbonate group, an amide group, and these and a group in which a plurality of is linked. Incidentally, the cyclohexene oxide group in formula (i) may be bonded with a substituent (for example, an alkyl group, etc.).

Examples of the divalent hydrocarbon group include linear or branched alkylene groups having 1 to 18 carbon atoms, divalent alicyclic hydrocarbon groups, and the like. Examples of linear or branched alkylene groups having 1 to 18 carbon atoms include methylene group, methylmethylene group, dimethylmethylene group, ethylene group, propylene group and trimethylene group. Examples of the divalent alicyclic hydrocarbon group include 1,2-cyclopentylene group, 1,3-cyclopentylene group, cyclopentylidene group, 1,2-cyclohexylene group, 1,3- Cycloalkylene groups (including cycloalkylidene groups) such as a cyclohexylene group, a 1,4-cyclohexylene group, and a cyclohexylidene group are included.

Examples of the alkenylene group in the alkenylene group in which part or all of the carbon-carbon double bond is epoxidized (sometimes referred to as "epoxidized alkenylene group") include vinylene group, propenylene group, and 1-butenylene group. , 2-butenylene group, butadienylene group, pentenylene group, hexenylene group, heptenylene group, octenylene group, and other linear or branched alkenylene groups having 2 to 8 carbon atoms. In particular, the epoxidized alkenylene group is preferably an alkenylene group in which all of the carbon-carbon double bonds are epoxidized, more preferably an alkenylene group having 2 to 4 carbon atoms in which all of the carbon-carbon double bonds are epoxidized. It is an alkenylene group.

As the linking group for X, a linking group containing an oxygen atom is particularly preferable, and specifically, -CO-, -O-CO-O-, -COO-, -O-, -CONH-, epoxy a modified alkenylene group; a group in which a plurality of these groups are linked; a group in which one or more of these groups are linked to one or more of the above divalent hydrocarbon groups;

Representative examples of the compound represented by formula (i) above include (3,4,3′,4′-diepoxy)bicyclohexyl, bis(3,4-epoxycyclohexylmethyl)ether, 1,2- Epoxy-1,2-bis(3,4-epoxycyclohexan-1-yl)ethane, 2,2-bis(3,4-epoxycyclohexan-1-yl)propane, 1,2-bis(3,4- Examples thereof include epoxycyclohexan-1-yl)ethane and compounds represented by the following formulas (i-1) to (i-10). L in the following formula (i-5) is an alkylene group having 1 to 8 carbon atoms. alkylene groups are preferred. n ¹ to n ⁸ in the following formulas (i-5), (i-7), (i-9) and (i-10) each represent an integer of 1 to 30.

Epoxy-modified siloxane is also included in the compound (i) having an alicyclic epoxy group described above.

Examples of epoxy-modified siloxanes include linear or cyclic polyorganosiloxanes having structural units represented by the following formula (i').

In formula (i') above, R ¹ represents an epoxy group-containing substituent represented by the following formula (1a) or (1b), and R ² represents an alkyl group or an alkoxy group.

In the formula, R ^1a and R ^1b are the same or different and represent a linear or branched alkylene group, such as methylene group, methylmethylene group, dimethylmethylene group, ethylene group, propylene group, trimethylene group, tetra Linear or branched alkylene groups having 1 to 10 carbon atoms such as methylene group, pentamethylene group, hexamethylene group and decamethylene group can be mentioned.

The epoxy equivalent of the epoxy-modified siloxane (according to JIS K7236) is, for example, 100-400, preferably 150-300.

Examples of the epoxy-modified siloxane include commercial products such as epoxy-modified cyclic polyorganosiloxane represented by the following formula (i'-1) (trade name "X-40-2670", manufactured by Shin-Etsu Chemical Co., Ltd.). can be used.

Examples of the compound (ii) having an epoxy group directly bonded to the alicyclic ring with a single bond include compounds represented by the following formula (ii).

In formula (ii), R' is a group (p-valent organic group) obtained by removing p hydroxyl groups (-OH) from the structural formula of p-valent alcohol, and p and ⁿ⁹ each represent a natural number. Examples of the p-valent alcohol [R'-(OH) _p ] include polyhydric alcohols (such as alcohols having 1 to 15 carbon atoms) such as 2,2-bis(hydroxymethyl)-1-butanol. p is preferably 1-6, and n ⁹ is preferably 1-30. When p is 2 or more, n ⁹ in groups within each square bracket (outer bracket) may be the same or different. Specific examples of the compound represented by the above formula (ii) include a 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol [for example, , trade name “EHPE3150” (manufactured by Daicel Corporation), etc.] and the like.

Examples of the compound (iii) having an alicyclic ring and a glycidyl group described above include hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated biphenol type epoxy compounds, hydrogenated phenol novolac type epoxy compounds, Hydrogenated aromatic glycidyl ether epoxy compounds such as hydrogenated cresol novolak type epoxy compounds, hydrogenated cresol novolac type epoxy compounds of bisphenol A, hydrogenated naphthalene type epoxy compounds, hydrogenated products of trisphenolmethane type epoxy compounds, and the like. be done.

As the polyfunctional alicyclic epoxy compound, the compound (i) having an alicyclic epoxy group is preferable in that a cured product having high surface hardness and excellent transparency can be obtained, and is represented by the above formula (i). Compounds (especially (3,4,3′,4′-diepoxy)bicyclohexyl) are particularly preferred.

The curable resin composition in the present invention may contain other curable compounds other than the epoxy resin as the curable compound. It can contain more than one species.

The ratio of the epoxy resin to the total amount of curable compounds (100% by weight) contained in the curable resin composition is, for example, 50% by weight or more, preferably 60% by weight or more, particularly preferably 70% by weight or more, and most preferably 80% by weight or more. The upper limit is, for example, 100% by weight, preferably 90% by weight.

In addition, the ratio of the compound (i) having an alicyclic epoxy group to the total amount of curable compounds (100% by weight) contained in the curable resin composition is, for example, 20% by weight or more, preferably 30% by weight or more, and particularly Preferably, it is 40% by weight or more. The upper limit is, for example, 70% by weight, preferably 60% by weight.

Further, the ratio of the compound represented by formula (i) to the total amount of curable compounds (100% by weight) contained in the curable resin composition is, for example, 10% by weight or more, preferably 15% by weight or more, and particularly preferably is 20% by weight or more. The upper limit is, for example, 50% by weight, preferably 40% by weight.

The curable resin composition preferably contains a polymerization initiator together with the curable compound, and contains one or more photo- or thermal polymerization initiators (especially photo- or thermal cationic polymerization initiators). preferably.

A photocationic polymerization initiator is a compound that generates an acid upon irradiation with light and initiates a curing reaction of a curable compound (in particular, a cationic curable compound) contained in a curable resin composition, and absorbs light. It consists of a cation part and an anion part that is a source of acid generation.

Examples of photocationic polymerization initiators include diazonium salt compounds, iodonium salt compounds, sulfonium salt compounds, phosphonium salt compounds, selenium salt compounds, oxonium salt compounds, ammonium salt compounds, bromine salt compounds, and the like. can be mentioned.

In the present invention, among others, it is preferable to use a sulfonium salt compound because a cured product having excellent curability can be formed. Examples of the cation moiety of the sulfonium salt compound include (4-hydroxyphenyl)methylbenzylsulfonium ion, triphenylsulfonium ion, diphenyl[4-(phenylthio)phenyl]sulfonium ion, 4-(4-biphenylylthio)phenyl Arylsulfonium ions (especially triarylsulfonium ions) such as -4-biphenylylphenylsulfonium ion and tri-p-tolylsulfonium ion can be mentioned.

Examples of the anion portion of the photocationic polymerization initiator include [(Y) _s B(Phf) _4-s ] ⁻ (wherein Y represents a phenyl group or a biphenylyl group. Phf represents at least one hydrogen atom a phenyl group substituted with at least one selected from a perfluoroalkyl group, a perfluoroalkoxy group, and a halogen atom, where s is an integer of 0 to 3), BF ₄ ⁻ , [(Rf) _t PF _6-t ] ⁻ (wherein Rf represents an alkyl group in which 80% or more of the hydrogen atoms are substituted with fluorine atoms; t represents an integer of 0 to 5), AsF ₆ ⁻ , SbF ₆ ⁻ , SbF ₅ OH ^- and the like.

Examples of photocationic polymerization initiators include (4-hydroxyphenyl)methylbenzylsulfonium tetrakis(pentafluorophenyl)borate, 4-(4-biphenylylthio)phenyl-4-biphenylylphenylsulfonium tetrakis(pentafluorophenyl) borate, 4-(phenylthio)phenyldiphenylsulfonium phenyltris(pentafluorophenyl)borate, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium phenyltris(pentafluorophenyl)borate, diphenyl[4 -(phenylthio)phenyl]sulfonium tris(pentafluoroethyl)trifluorophosphate, diphenyl[4-(phenylthio)phenyl]sulfonium tetrakis(pentafluorophenyl)borate, diphenyl[4-(phenylthio)phenyl]sulfonium hexafluorophosphate, 4 -(4-biphenylylthio)phenyl-4-biphenylylphenylsulfonium tris(pentafluoroethyl)trifluorophosphate, bis[4-(diphenylsulfonio)phenyl]sulfide phenyltris(pentafluorophenyl)borate, [4- (2-thioxanthonylthio)phenyl]phenyl-2-thioxanthonylsulfonium phenyltris(pentafluorophenyl)borate, 4-(phenylthio)phenyldiphenylsulfonium hexafluoroantimonate, trade name “Cyracure UVI-6970”, “ Cyracure UVI-6974", "Cyracure UVI-6990", "Cyracure UVI-950" (manufactured by Union Carbide, USA), "Irgacure250", "Irgacure261", "Irgacure264", "CG-24-61" (above , manufactured by BASF), “Optomer SP-150”, “Optomer SP-151”, “Optomer SP-170”, “Optomer SP-171” (manufactured by ADEKA Corporation), “DAICAT II” (manufactured by ) manufactured by Daicel), “UVAC1590”, “UVAC1591” (manufactured by Daicel Cytec Co., Ltd.), “CI-2064”, “CI-2639”, “CI-2624”, “CI-2481”, “CI -2734", "CI-2855", "CI-2823", "CI-2758" , "CIT-1682" (manufactured by Nippon Soda Co., Ltd.), "PI-2074" (manufactured by Rhodia, tetrakis (pentafluorophenyl) borate trilycumyl iodonium salt), "FFC509" (manufactured by 3M), "BBI-102", "BBI-101", "BBI-103", "MPI-103", "TPS-103", "MDS-103", "DTS-103", "NAT-103", "NDS -103” (manufactured by Midori Chemical Co., Ltd.), “CD-1010”, “CD-1011”, “CD-1012” (manufactured by Sartomer, USA), “CPI-100P”, “CPI- 101A" (manufactured by San-Apro Co., Ltd.).

The thermal cationic polymerization initiator is a compound that generates acid by heat treatment and initiates the curing reaction of the cationic curable compound contained in the curable resin composition. It consists of an anion part that serves as a generation source. A thermal cationic polymerization initiator can be used individually by 1 type or in combination of 2 or more types.

Examples of thermal cationic polymerization initiators include iodonium salt compounds and sulfonium salt compounds.

Examples of the cationic moiety of the thermal cationic polymerization initiator include 4-hydroxyphenyl-methyl-benzylsulfonium ion, 4-hydroxyphenyl-methyl-(2-methylbenzyl)sulfonium ion, 4-hydroxyphenyl-methyl-1-naphthyl Methylsulfonium ion, p-methoxycarbonyloxyphenyl-benzyl-methylsulfonium ion and the like can be mentioned.

Examples of the anion portion of the thermal cationic polymerization initiator include the same examples as the anion portion of the photocationic polymerization initiator.

Thermal cationic polymerization initiators include, for example, 4-hydroxyphenyl-methyl-benzylsulfonium phenyltris(pentafluorophenyl)borate and 4-hydroxyphenyl-methyl-(2-methylbenzyl)sulfonium phenyltris(pentafluorophenyl)borate. , 4-hydroxyphenyl-methyl-1-naphthylmethylsulfonium phenyltris(pentafluorophenyl)borate, p-methoxycarbonyloxyphenyl-benzyl-methylsulfonium phenyltris(pentafluorophenyl)borate and the like.

The content of the polymerization initiator is, for example, in the range of 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the curable compound (particularly the cationic curable compound) contained in the curable resin composition. If the content of the polymerization initiator is less than the above range, there is a risk of causing poor curing. On the other hand, when the content of the polymerization initiator exceeds the above range, the cured product tends to be easily colored.

The curable resin composition in the present invention comprises the above curable compound, a polymerization initiator, and optionally other components (e.g., solvent, antioxidant, surface modifier, photosensitizer, antifoaming agent, leveling agent, etc.). agent, coupling agent, surfactant, flame retardant, ultraviolet absorber, colorant, etc.). The blending amount of other components is, for example, 20% by weight or less, preferably 10% by weight or less, particularly preferably 5% by weight or less, of the total amount of the curable resin composition.

The viscosity at 25° C. of the curable resin composition of the present invention is not particularly limited, but is preferably 5000 mPa·s or less, more preferably 2500 mPa·s or less. By adjusting the viscosity of the curable resin composition of the present invention to the above range, the fluidity is improved, air bubbles are less likely to remain, and it is possible to fill the mold while suppressing an increase in injection pressure. . That is, it is possible to improve the applicability and the filling property, and to improve the workability over the entire molding operation of the curable resin composition of the present invention. The viscosity as used herein is a value measured using a rheometer (“PHYSICA UDS200” manufactured by Paar Physica) under the conditions of a temperature of 25° C. and a rotation speed of 20/sec.

As the curable resin composition in the present invention, for example, commercially available products such as trade names "CELVENUS OUH106" and "CELVENUS OTM107" (manufactured by Daicel Corporation) can be used.

Curing of the curable material can be performed by irradiating ultraviolet rays, for example, when a photocurable resin composition is used as the curable resin composition. A high-pressure mercury lamp, an extra-high pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, or the like is used as a light source for ultraviolet irradiation. The irradiation time varies depending on the type of light source, the distance between the light source and the coated surface, and other conditions, but it is several tens of seconds at the longest. The illuminance is about 5 to 200 mW. After the ultraviolet irradiation, heating (post-curing) may be performed as necessary to promote curing.

For example, when a thermosetting resin composition is used as the curable resin composition, the curable resin composition can be cured by heat treatment. The heating temperature is, for example, about 60 to 150.degree. The heating time is, for example, about 0.5 to 20 hours.

As a method of supplying the curable material to the molding surface of the mold of the present invention and curing it, preferably, an imprint molding method can be used. For example, the following methods (1) to (3) can be used. mentioned.
(1) A method in which a curable material is applied to the molding surface of the mold of the present invention, a substrate is adhered thereon, the coating film of the curable material is cured, and the substrate is peeled off (2) ) A method in which the molding surface of the mold of the present invention is pressed against the coating film of the curable material applied on the substrate, and the coating film of the curable material is cured, and then the substrate is peeled off. A method in which a curable material is applied to the molding surface of a mold, a substrate coated with the curable material is brought into close contact with the substrate, the combined coating film of the curable material is cured, and the substrate is peeled off.

For example, when a photocurable resin composition is used as the curable material, it is preferable to use a substrate having a light transmittance of 90% or more at a wavelength of 400 nm as the substrate, and a substrate made of quartz, glass, or resin. can be preferably used. The light transmittance of the above wavelength is obtained by using a substrate (thickness: 1 mm) as a test piece and measuring the light transmittance of the above wavelength irradiated to the test piece using a spectrophotometer.

For example, when a thermosetting resin composition is used as the curable material, the curable resin composition can be cured by heat treatment. The heating temperature is, for example, about 60 to 150.degree. The heating time is, for example, about 0.5 to 20 hours.

In the above methods (1) to (3), the surface of the molded product exposed by peeling the substrate is the second surface, held on the molding surface of the mold of the present invention, and the pattern shape is reversely transferred. The face is the first face.

The substrate may be a mold having patterned portions, or may be a flat substrate. For example, a flat substrate can be used when the second surface of the molded article of the present invention does not have an irregular shape. On the other hand, when the second surface has an uneven shape, a mold having a corresponding uneven shape can be used as the substrate, but it is preferable to have at least a flat portion. Since the substrate has a flat portion, the flat portion is transferred to the second surface, and the pressure-sensitive adhesive sheet of the present invention can be attached and easily fixed stably.

The substrate may be made of a material different from that of the mold of the present invention, or may be made of the same material. The substrate and the molding surface of the mold of the present invention may have the same or corresponding pattern shapes, or may have different pattern shapes.

At least one of the molding surface of the mold of the present invention and the substrate before being superimposed is coated with a curable material. It is preferable to use a mold whose molding surface is coated with a curable material. In this case, the substrate may or may not be coated with a curable material.

Application of the curable material to the molding surface of the mold of the present invention and/or the substrate can be performed by a known or commonly used application method. Examples of the coating include spin coating, roll coating, spray coating (spray atomization), dispense coating, dip coating, inkjet coating, air brush coating (air brush spraying), ultrasonic coating (ultrasonic spraying), and the like. mentioned.

By the above methods (1) to (3), a molded product is obtained in which the first surface is attached to the molding surface of the mold. FIG. 3 shows a schematic diagram of an example of a state in which the first surface of the molded article is attached to the molding surface of the mold. (a) is a perspective view, (b) is a top view, and (c) is a side view.

The first surface 2A of the molded product 2 is attached to the molding surface 1A of the mold 1, and the pattern area 11 (not shown) of the molding surface 1A and the pattern shape of the pattern area 11 are reversely transferred to a transfer area 21 (not shown). The pattern shape is not shown) are in close contact with each other. Therefore, when the molded product 2 is released from the molding surface 1A of the mold 1, a load is applied to the pattern shape formed in the transfer area 21, and the entire molded product 2 is warped or the positional accuracy of the pattern shape is deteriorated. Cheap.

The first step of the mold release method of the present invention is a step of attaching an adhesive sheet having an adhesive strength of 3 N/20 mm or more to the entire second surface of the molded product.

[Adhesive sheet]
The adhesive sheet of the present invention is characterized by having an adhesive strength of 3 N/20 mm or more. Since the pressure-sensitive adhesive sheet has an adhesive strength of 3 N/20 mm or more, the molded product can be reliably released from the molding surface of the mold while the pressure-sensitive adhesive sheet of the present invention is held on the second surface. It becomes easier to distribute the load uniformly over the entire molded product, and the accuracy of the molded product can be improved. That is, when the adhesive strength of the pressure-sensitive adhesive sheet of the present invention is less than 3 N/20 mm, the pressure-sensitive adhesive sheet cannot be sufficiently adhered to the second surface, and the release itself becomes difficult, or the release is possible. However, a large load tends to be applied to a portion of the molded product at the start of mold release, and the accuracy of the molded product tends to deteriorate. From the viewpoint of further improving the precision of molded products, the adhesive strength of the pressure-sensitive adhesive sheet of the present invention is preferably 3 N/20 mm or more, more preferably 4 N/20 mm or more, and even more preferably 5 N/20 mm or more.

On the other hand, the upper limit of the adhesive strength of the adhesive sheet of the present invention is not particularly limited, but is preferably 25 N/20 mm or less, more preferably 24 N/20 mm or less, still more preferably 23 N/20 mm or less. When the adhesive strength of the adhesive sheet of the present invention exceeds 25 N/20 mm, it becomes difficult to peel the adhesive sheet of the present invention from the second surface of the molded product after releasing the molded product from the mold, and the adhesive sheet is peeled off. In some cases, the accuracy of the molded product is lowered, and adhesive residue may be left on the second surface after peeling.
The adhesive strength is a value measured as a 180° peel adhesive strength to a silicon mirror wafer in accordance with JIS-Z-0237.

FIG. 4 shows a schematic diagram of an example of the pressure-sensitive adhesive sheet of the present invention. (a) is a perspective view, (b) is a top view, (c) is a side view, and (d) is an enlarged view of the side view.

The configuration of the pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it is a sheet-like material exhibiting adhesiveness on at least one surface. It is preferably a laminate in which a base material 31 and an adhesive layer 32 are laminated on one surface of the base material 31 .

The material constituting the base material 31 is not particularly limited, but paper, resin, nonwoven fabric, metal, glass, silicon, etc. can be used. Resins are preferred.

The resin as a material constituting the base material 31 is not particularly limited, but examples include polyolefins such as polyethylene and polypropylene, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinyl chloride-vinyl acetate copolymer, poly (Meth)acrylate, polystyrene, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, cellulose derivatives such as cellulose acetate, polyester (polyalkylene terephthalate such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, etc.) polyalkylene naphthalate, etc.), polycarbonate, polyamide (polyamide 6, polyamide 6/6, polyamide 6/10, polyamide 6/12, etc.), polyesteramide, polyether, polyimide, polyamideimide, polyetherester, etc. Furthermore, copolymers, blends, and crosslinked products thereof may also be used. Polyester resins and polyolefin resins are preferred in order to uniformly distribute the load during releasing from the mold over the entire molded product.

Although the thickness of the base material 31 is not particularly limited, it is preferably 50 to 300 μm, more preferably 50 to 200 μm in order to uniformly distribute the load during releasing over the entire molded product.

Although the breaking stress of the base material 31 is not particularly limited, it is preferably 20 to 200 MPa, more preferably 25 to 180 MPa. When the breaking stress of the base material 31 is within this range, it becomes easier to uniformly distribute the load at the time of mold release over the entire molded product. That is, if the breaking stress of the substrate 31 is lower than 20 MPa, the pressure-sensitive adhesive sheet of the present invention may become too soft, making it difficult to evenly distribute the load during release over the entire molded product. On the other hand, if the breaking stress of the base material 31 is higher than 200 MPa, the pressure-sensitive adhesive sheet of the present invention may become too hard and release itself may become difficult.
The breaking stress is a value measured with a sample size of 15 mm×10 mm and a tensile speed of 200 mm/min.

The adhesive constituting the adhesive layer 32 is not particularly limited, but acrylic adhesive, rubber adhesive (natural rubber adhesive, synthetic rubber adhesive, etc.), silicone adhesive, polyester adhesive. , urethane-based adhesives, polyamide-based adhesives, epoxy-based adhesives, vinyl alkyl ether-based adhesives, fluorine-based adhesives, and the like can be used. Only 1 type may be used for the said adhesive, and 2 or more types may be used for it. The adhesive may be of any type such as an emulsion adhesive, a solvent adhesive, a hot-melt adhesive, an oligomer adhesive, or a solid adhesive. An acrylic pressure-sensitive adhesive or the like is preferable from the viewpoint of facilitating uniform distribution of the load during releasing from the mold over the entire molded product.

The adhesive layer 32 may be a single layer, or may be a laminate comprising a plurality of layers, and when comprising a plurality of layers, may be a laminate of the same type of adhesive layers, It may be a laminate of different types of pressure-sensitive adhesive layers. Further, it may be laminated on the substrate 31 via an intermediate layer, an undercoat layer, or the like.

The adhesive layer 32 may be laminated on the entire one surface of the substrate 31, and may be laminated on one surface of the substrate 31 as long as the adhesive layer 32 can adhere to the entire second surface of the molded article. It may be laminated on the part.

The adhesive layer 32 may be protected with a release sheet, in which case the release sheet is removed prior to use in the release method of the present invention.

Although the thickness of the pressure-sensitive adhesive layer 32 is not particularly limited, it is preferably 5 to 50 μm, more preferably 5 to 40 μm, from the viewpoint of facilitating uniform distribution of the load during release over the entire molded product.

The adhesive strength of the adhesive layer 32 is not particularly limited as long as the adhesive strength is sufficient to release the molded article from the molding surface of the mold while the adhesive sheet of the present invention is held on the second surface. can be reliably released from the molding surface of the mold, and the load during release is uniformly distributed over the entire molded product to improve the accuracy of the molded product. It is preferable to adjust the adhesive strength to the same range as the adhesive strength of the sheet.

The adhesive that constitutes the adhesive layer 32 may be of a non-curable type or of a curable type. When the adhesive is a curable type, it may be a thermosetting type or a photocurable type (curable by active energy rays such as ultraviolet rays and electron beams). When the adhesive is a curable type, the adhesive is cured by heating or light irradiation after the release method of the present invention, so that the obtained molded article of the present invention is peeled from the adhesive sheet of the present invention. easier to do.

FIG. 5 shows an example of the first step of the mold release method of the present invention. The adhesive sheet 3 of the present invention is attached to the entire second surface 2B of the molded product 2 of the present invention.

"The adhesive sheet is attached to the entire second surface" means that the adhesive sheet of the present invention is attached not only to the non-transfer area 22 of the second surface but also to the entire surface of the second surface corresponding to the transfer area 21. means to stick However, if there is a recess on the second surface, the recess does not have to be in contact with the adhesive sheet. In other words, it is sufficient that the entire planar portion existing on the second surface is attached to the pressure-sensitive adhesive sheet of the present invention.

The area of the pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it is larger than the second surface of the molded article of the present invention. It is preferably wider than the molding surface of the inventive mold. The ratio of the area of the adhesive sheet of the present invention to the molding surface area (100%) of the mold of the present invention is not particularly limited, but is preferably 100 to 500%, more preferably 100 to 400%.

The thickness of the pressure-sensitive adhesive sheet of the present invention (the total thickness of the substrate 31 and the pressure-sensitive adhesive layer 32) is not particularly limited. 55 to 350 μm, more preferably 55 to 240 μm.

As the pressure-sensitive adhesive sheet of the present invention, commercially available pressure-sensitive adhesive sheets can be used without limitation. Adhesive tapes, UV peeling tapes, heat peeling tapes, etc., which are generally sold by

Although the first step of the mold release method of the present invention is not particularly limited, it can be carried out by sticking the pressure-sensitive adhesive sheet of the present invention on the entire second surface of the molded article so as to be in close contact therewith. The second surface of the pressure-sensitive adhesive sheet of the present invention and the non-adhered surface may be pressed with a roller or the like so that the pressure-sensitive adhesive sheet of the present invention is firmly adhered to the entire second surface.

In the second step of the mold release method of the present invention, the molded product of the present invention is released from the mold by relatively moving the adhesive sheet and the mold in the direction in which the adhesive sheet of the present invention and the mold of the present invention are separated. It is a process to do. In the second step, the molded product is released from the molding surface of the mold while being held by the adhesive sheet.

The movement of the adhesive sheet and/or the mold may be relative as long as they are separated from each other, and the adhesive sheet alone, the mold alone, or both may be moved. In order to release the molded product immediately, it is preferable to fix the mold and move the pressure-sensitive adhesive sheet away from the mold.

The movement of the adhesive sheet and/or the mold is not particularly limited, but may be performed manually. For example, the adhesive sheet may be moved by holding the ends of the adhesive sheet on a holding member.

FIG. 6 shows an example of the second step of the mold release method of the present invention. (a) is a perspective view, and (b) is a side view. One end of the adhesive sheet 3 is held manually or by a holding member, and as shown in FIGS. 6(a2) and (b2), the adhesive sheet and the mold are diagonally separated, and the mold 1 is held while the molded product 2 is held on the adhesive sheet 3, as shown in FIGS. Release from the molding surface.

FIG. 7 shows another example of the second step of the mold release method of the present invention. (a) is a perspective view, and (b) is a side view. At least two or more ends of the adhesive sheet 3 are held manually or by a holding member, and as shown in FIGS. 7 (a2) and (b2), the pressure-sensitive adhesive sheet and the mold are horizontally separated, and the molded product 2 is held on the pressure-sensitive adhesive sheet 3 while being separated from the molding surface of the mold 1. mold.

In order to distribute the load evenly over the entire molded product and improve the accuracy of the molded product when the mold is released, the end of the adhesive sheet of the present invention is tilted from the mold as shown in FIG. It is preferable to separate them from each other and release the molded product from the molding surface of the mold while holding the molded product on the adhesive sheet.

By the mold release method of the present invention, it is possible to obtain a molded product in which the second surface is attached to the pressure-sensitive adhesive sheet of the present invention. FIG. 8 shows a schematic diagram of an example of a molded article having a second surface to which the pressure-sensitive adhesive sheet obtained by the mold release method of the present invention is attached. (a) is a perspective view, (b) is a top view, and (c) is a sectional view taken along line XX'.

FIG. 8(a) shows a perspective view of the molded product 2 with the second surface 2B adhered to the adhesive sheet 3. FIG. On the first surface 2A of the molded product 2, a transfer area 21 (the pattern shape is not shown) is exposed.

FIG. 8(b) shows a top view of the molded product 2 with the second surface 2B attached to the adhesive sheet 3, and FIG. 8(c) shows a cross-sectional view taken along line XX'. In FIG. 8(b), two or more optical elements 23 are two-dimensionally arranged in the transfer area 21 of the first surface 2A of the molded product 2. As shown in FIG. According to the mold release method of the present invention, when the molded product 2 is released from the molding surface 1A of the mold 1, the load is uniformly applied to the entire molded product 2. Therefore, the warp of the molded product 2 is small, and two or more pieces are formed. The positional accuracy between the optical elements 23 is excellent.

The mold release method of the present invention may further include the following third step after the second step.
Third step: peeling off the pressure-sensitive adhesive sheet from the second surface of the molded article obtained in the second step.

Through the third step, the pressure-sensitive adhesive sheet can be peeled off from the second surface of the molded article to obtain, for example, the molded article 2 shown in FIG.

The method of peeling off the adhesive sheet from the second surface of the molded product is not particularly limited, and at least one end of the adhesive sheet is held, and the adhesive sheet and/or the molded product are relatively moved in a direction away from the molded product. This can be done by moving away from the The relative movement of the adhesive sheet and/or the molded product is not particularly limited, but can be performed in the same manner as the method of relatively moving the adhesive sheet and/or the mold shown in FIGS. 6 and 7, for example.

As described above, when the adhesive of the adhesive layer 32 of the adhesive sheet of the present invention is of a curable type, the adhesive is cured by heating or light irradiation, so that the molded article of the present invention can be peeled off from the adhesive sheet. easier to do.

Further, when the molded product is an optical element array, it is also preferable that the mold release method of the present invention further includes the following 3′ process after the second process.
3' step: a molded product obtained in the second step, having a plurality of optical elements arranged two-dimensionally on the first surface and having the second surface fixed with an adhesive sheet (i.e., the optical element By dicing the array), the optical elements are separated into individual optical members.

8(b) and 8(c) show a state in which the second surface 2B of the molded product 2, which is the optical element array, is fixed to the adhesive sheet 3. FIG. Since the adhesive sheet 3 can also function as a dicing tape, by dicing the molded product 2, which is the optical element array fixed to the adhesive sheet 3, the optical elements 23 can be separated into individual optical members.

By dicing the molded article 2, which is an optical element array, along cutting lines 24 in FIG. 8B, the optical elements 23 can be separated into individual pieces. By dicing, an optical member is obtained in which a substrate portion corresponding to the substrate of the molded product 2 is bonded to the periphery of the individualized optical element 23 . The molded product 2, which is an optical element array obtained by the mold release method of the present invention, has little warpage, high positional accuracy of the two or more optical elements 23, and small deviation, so that a plurality of optical members having the same shape can be produced. Obtainable.

The means for separating the optical element array into individual pieces is not particularly limited, and known and commonly used means can be employed. Among them, it is preferable to use a dicing blade that rotates at a high speed.

When cutting using a dicing blade that rotates at high speed, the rotation speed of the dicing blade is, for example, about 10000 to 50000 rpm. In addition, since frictional heat is generated when the optical element array is cut using a blade or the like that rotates at high speed, cutting while cooling the optical element array is not recommended because the frictional heat may cause the optical elements to deform or their optical characteristics to deteriorate. It is preferable in that it is possible to suppress the decrease.

When cutting the optical element array using a dicing blade, it is preferable not to cut the adhesive sheet of the present invention. In this case, the separated optical members are fixed to the adhesive sheet on the second surface, and the optical members can be taken out by picking up the respective optical members from the adhesive sheet.

The mold release method of the present invention may be implemented by the mold release apparatus of the present invention. Hereinafter, the mold release device 100 of the present invention will be described with reference to FIGS. 9 and 10. FIG. FIG. 9 is a block diagram showing the demolding device 100 of the present invention.

As shown in FIG. 9, the release device 100 of the present invention includes a sticking section (sticking means) 101 and a moving section (moving means) 102. A control section 110 includes a sticking control section (sticking control means). 111 and a movement control unit (movement control means) 112 .

In the mold release device 100 of the present invention, the attaching section 101 attaches the adhesive sheet of the present invention to the second surface of the molded product attached to the molding surface of the mold. The moving part 102 relatively moves the adhesive sheet and/or the mold in the separating and contacting direction. The moving unit 102 may move only the adhesive sheet, may move only the mold, or may move both the adhesive sheet and the mold. Preferably, only the sheet is moved. The control unit 110 controls the sticking unit 101 and the moving unit 102 to execute the mold release method of the present invention.

Next, processing of each unit of the control unit 110 will be described with reference to FIG. FIG. 10 is a flow chart showing the flow of the mold release method of the present invention.

The sticking control section 111 controls the sticking section 101 so as to perform the first step of sticking the adhesive sheet of the present invention on the second surface. The sticking section 101 sticks the pressure-sensitive adhesive sheet of the present invention to the entire second surface of the molded product under the control of the sticking control section 111 (S1: first step). In the release device 100 of the present invention, the sticking unit 101 and the sticking control unit 111 can use a commercially available adhesive sheet sticking device and its control unit as they are, and there is no need to separately construct a high-precision control system. do not have.

After the first step, the movement control unit 112 controls the moving unit 102 to perform the second step of relatively moving the adhesive sheet and the mold in the direction in which the adhesive sheet and/or the mold are separated. The moving unit 102 relatively moves the adhesive sheet and/or the mold away from each other under the control of the movement control unit 112 (S2: second step). The movement control unit 112 holds the end of the adhesive sheet with a holding member (for example, a robot hand) of the moving unit 102, and applies a force F to the end of the adhesive sheet as shown in FIG. Adjusting is preferred. In the mold release apparatus 100 of the present invention, the moving unit 102 and the moving control unit 112 can use commercially available robot hands, robot arms and their control units as they are, and there is no need to separately construct a highly accurate control system. do not have.

The mold release apparatus of the present invention may have a second movement section and a second movement control section for carrying out the third step, if necessary. A commercially available robot hand, a robot arm, and its control unit similar to the moving unit 102 and the movement control unit 112 can be used for the second moving unit and the second movement control unit.

The mold release apparatus of the present invention may have a dicing section and a dicing control section for carrying out the 3′ process, if necessary. As the dicing section and the dicing control section, a commercially available dicing machine and its control section can be used.

The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. is also included in the technical scope of the present invention.

Examples and comparative examples are given for typical embodiments of the present invention, but the present invention is not intended to be limited thereto, but merely illustrative.
The adhesive strength of the adhesive sheets used in Examples and Comparative Examples was measured as 180° peel adhesive strength to a silicon mirror wafer in accordance with JIS-Z-0237.

Production example 1
A silicone resin mold (lower mold 4) having a diameter of 150 mm and a height of 3 mm as shown in FIG. 11 was prepared. (a) is a top view, and (b) is a cross-sectional view taken along line AA'. A plurality of recesses 41 are arranged on the molding surface of the lower mold 4 as shown in FIG. 11(a).
After dip-coating the molding surface of the lower mold 4 with a fluorine-based release agent (OPTOOL HD-1100, manufactured by Daikin Industries, Ltd.), 10 g of an epoxy resin (CELVENUS106, manufactured by Daicel Corporation) is dropped. Then, a silicone resin plate (upper mold 5, flat substrate) of the same size whose surface has been subjected to a release treatment with a fluorine-based release agent is closed to a thickness of about 0.5 mm (FIG. 12(a)). See), UV irradiation was performed at 100 mW/cm ² ×30 seconds. When the upper mold 5 is removed, a resin wafer 6 having convex portions 61 formed at positions corresponding to the concave portions 41 of the lower mold 4 is obtained as a hardened epoxy resin adhered to the molding surface of the lower mold 4 . (See FIG. 12(b)).

Example 1
An adhesive sheet having an adhesive force of 17 N/20 mm on the entire surface formed by removing the upper mold 5 of the resin wafer 6 from the state in which the resin wafer 6 is attached to the molding surface of the lower mold 4 obtained in Production Example 1. (ADWILL D-210, Lintec Co., Ltd., base material: polyethylene phthalate, adhesive layer: acrylic adhesive) is attached, and the end of the adhesive sheet is pressed in an oblique direction as shown in FIG. The resin wafer 6 was released from the lower mold 4 by applying F and pulling.

Example 2
Example 1 except that an adhesive sheet (UC3044M-110B, manufactured by Furukawa Electric Co., Ltd., base material: polyolefin, adhesive layer: acrylic adhesive) having an adhesive strength of 3.4 N / 20 mm was used. The resin wafer 6 was released from the lower mold 4 in the same manner as in .

Comparative example 1
An adhesive sheet with an adhesive strength of 2.5 N / 20 mm (TL-85-250, manufactured by Lintec Corporation, base material: made of polyethylene phthalate, adhesive layer: acrylic adhesive) was used. As in Example 1, the resin wafer 6 was released from the lower mold 4 .

Comparative example 2
Except for using an adhesive sheet (P-366K, manufactured by Nitto Denko Corporation, base material: polyethylene, adhesive layer: ethylene/vinyl acetate adhesive) having an adhesive strength of 0.6 N/20 mm, An attempt was made to release the resin wafer 6 from the lower mold 4 in the same manner as in Example 1, but the adhesive sheet was separated from the resin wafer 6 and the resin wafer 6 could not be released.

<Evaluation>
The resin wafers obtained in Examples and Comparative Examples were subjected to the following evaluation tests.

The positional accuracy of the released resin wafer was measured with a CNC image measurement system (NEXIV-VMR-3030, manufactured by Nikon Corporation).
The positional accuracy was evaluated based on how much each projection 61 deviated from the position of the corresponding recess 41 of the lower die 4 in the X and Y directions with reference to the position of the center of the resin wafer 6 . Specifically, the coordinates of each X and Y are measured for four points of the convex portion 61 corresponding to the concave portions 41 of A to D about 50 mm apart from the concave portion 41 of the reference point 42 as measurement points, and the deviation from the concave portion 41 is measured. was evaluated by the size (mm). The measurement point of the projection 61 was the apex position of a hemisphere with a height of 0.2 mm and a diameter of 1 mm. Table 1 shows the results.

The mold release method and mold release apparatus of the present invention can be used for lenses, prisms, LEDs, organic EL elements, semiconductor lasers, transistors, solar cells, CCD image sensors, optical waveguides, optical fibers, alternative glass (e.g., display substrates, hard disk substrates). , polarizing films), optical diffraction elements, and other optical members.

1 mold
11 Pattern area 12 Non-pattern area 1A Molding surface 2 Molded product 21 Transfer area 22 Non-transfer area 23 Optical element 24 Cutting line 2A First surface 2B Second surface 3 Adhesive sheet 31 Base material 32 Adhesive layer F Force (of direction)
4 Lower mold (resin mold)
41 recess 42 reference point 5 upper die (resin plate)
6 resin wafer 61 convex part

Claims (9)

A molded product formed by curing a curable material supplied to the molding surface of the mold and having a first surface to which the pattern shape of the molding surface is transferred and a second surface on the back side is formed from the mold. A device for demolding,
A sticking means for sticking an adhesive sheet having an adhesive force of 3 N/20 mm or more and 25 N/20 mm or less on the second surface;
moving means for relatively moving the adhesive sheet and the mold;
a sticking control means for controlling the sticking means to stick the adhesive sheet to the entire second surface of the molded product, which is a cured product of the curable material;
and a movement control means for controlling the moving means to relatively move the adhesive sheet and the mold in a direction in which the adhesive sheet and the mold are separated from each other. ,
The mold releasing device, wherein the molded article is an array having two or more optical elements arranged two-dimensionally on the first surface and having a substrate portion connecting the optical elements to each other. Furthermore, a dicing means;
A dicing control means for controlling the dicing means to dice a molded article having a plurality of optical elements arranged two-dimensionally on a first surface and having a second surface fixed by the base material; 2. The release device of claim 1, comprising: 3. The mold release apparatus according to claim 1, wherein said optical element is a wafer level lens. The releasing device according to any one of claims 1 to 3, wherein the second surface has at least a flat portion to which the adhesive sheet is attached. The release according to any one of claims 1 to 4, wherein the adhesive sheet is a laminate in which an adhesive layer is laminated on one side of a base material and the base material, and the base material is a resin. mold device. a second moving means for relatively moving the base material and the molded product;
a second movement control means for controlling the second moving means to relatively move the base material and the molded product in a direction in which the base material and the molded product are separated from each other. The mold release device according to any one of 1 to 5. The mold release device according to any one of claims 1 to 6, wherein the curable material is a curable epoxy resin composition. The mold release device according to any one of claims 1 to 7, wherein the material forming the mold is at least one selected from the group consisting of resin, metal, and glass. The mold release device according to any one of claims 1 to 8, wherein at least part of the pattern area of the molding surface of the mold is treated with a mold release agent.

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