WO2019189256A1 - Method for manufacturing resin thin film stripped pieces - Google Patents

Abstract

The present invention is a method for manufacturing resin thin film stripped pieces, said method including: a step (1) for obtaining a multilayer film by forming a resin thin film on a base material film; a step (2) for forming cracks in the resin thin film by spraying a liquid thereon; and a step (3) for obtaining stripped pieces by stripping the resin thin film from the base material film. The liquid is preferably pure water. The step (2) is preferably performed with a spraying pressure of 0.15-50 MPa inclusive. The resin thin film is preferably formed of a cured product of a photo-curable liquid crystal composition. The resin thin film is preferably a cholesteric resin layer.

Description

Method for producing release piece of resin thin film

The present invention relates to a method for producing a peeled piece of a resin thin film.

Conventionally, a technique using a small piece obtained by pulverizing a resin thin film as a pigment is known. Such a pigment is generally produced by forming a resin thin film on a base film, peeling the resin thin film from the base film, and then crushing the peeled resin thin film (see Patent Document 1). ).

JP 2001-261739 A (corresponding publication: US Patent Application Publication No. 2002/017633)

However, the conventional method has a problem that it is difficult to efficiently perform the process of peeling the resin thin film from the base film.

Therefore, an object of the present invention is to provide a method for producing a release piece of a resin thin film formed on a base film, which can efficiently produce the release piece.

As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that a peeling piece can be efficiently manufactured by spraying a liquid on a resin thin film to form a crack and then peeling the resin thin film. The headline and the present invention were completed.
That is, the present invention is as follows.

[1] A step (1) of forming a resin thin film on a base film to obtain a multilayer film;
(2) forming a crack by spraying a liquid on the resin thin film;
And (3) obtaining a peeled piece by peeling the resin thin film from the base film.
A method for producing a peeled piece of a resin thin film.
[2] The method for producing a peeled piece of a resin thin film according to [1], wherein the liquid is pure water.
[3] The method for producing a peeled piece of a resin thin film according to [1] or [2], wherein the step (2) is performed at a spraying pressure of 0.15 MPa to 50 MPa.
[4] The method for producing a peelable piece of a resin thin film according to any one of [1] to [3], wherein the resin thin film is made of a cured product of a photocurable liquid crystal composition.
[5] The method for producing a peeled piece of a resin thin film according to any one of [1] to [4], wherein the resin thin film is a cholesteric resin layer.
[6] The method for producing a peeled piece of a resin thin film according to any one of [1] to [5], wherein the peel strength between the base film and the resin thin film is 500 N / m or less.
[7] The method for producing a peeled piece of a resin thin film according to any one of [1] to [6], wherein the thickness of the resin thin film is 0.1 μm or more and 200 μm or less.

According to the present invention, it is possible to provide a method for producing a release piece of a resin thin film formed on a substrate film, which can efficiently produce the release piece.

FIG. 1 is a side view schematically showing an apparatus used in the method for producing a peelable piece of a resin thin film according to Embodiment 1. FIG. 2 is a cross-sectional view schematically showing a multilayer film used in the manufacturing method of Embodiment 1. FIG. 3 is a cross-sectional view schematically showing a multilayer film in which cracks are formed by spraying a liquid. FIG. 4 is a side view schematically showing a part of the manufacturing apparatus according to the first modification. FIG. 5 is a side view schematically showing a part of the manufacturing apparatus according to the second modification. FIG. 6 is a side view schematically showing a peeling piece manufacturing apparatus used in Comparative Example 1. FIG. FIG. 7 is a side view schematically showing a part of the manufacturing apparatus according to the third modification.

Hereinafter, the present invention will be described in detail with reference to embodiments and examples. However, this invention is not limited to embodiment shown below, In the range which does not deviate from the range of the claim of this invention, and its equivalent, it can implement arbitrarily.

In the following description, the “long” film refers to a film having a length of about 5 times or more, preferably 10 times or more of the film width. Refers to those having a length that is wound in a roll and stored or transported. The upper limit of the length of the long film is not particularly limited, and can be, for example, 100,000 times the width.

In the following description, the directions of the elements are “parallel”, “vertical” and “orthogonal”, unless otherwise specified, within a range that does not impair the effect of the present invention, for example, within ± 5 °. May be included. Further, “along” in a certain direction means “in parallel” in a certain direction.

In the following description, “(meth) acryl” includes acrylic, methacrylic, and combinations thereof. Further, “(meth) acrylate” includes acrylate, methacrylate, and combinations thereof. Further, “(thio) epoxy” includes epoxy, thioepoxy, and combinations thereof. The “iso (thio) cyanate” includes isocyanate, isothiocyanate, and combinations thereof.

[Embodiment 1: Manufacturing Method of Release Piece of Resin Thin Film]
[1. Overview of the method for producing a resin thin film release piece]
Hereinafter, a method for producing a peelable piece of a resin thin film according to Embodiment 1 of the present invention will be described with reference to FIGS.
The method for producing a peeled piece of a resin thin film according to this embodiment includes a step (1) of forming a resin thin film on a base film to obtain a multilayer film, and a step of spraying a liquid on the resin thin film to form a crack ( 2) and a step (3) of peeling the resin thin film from the base film to obtain a peeled piece.

FIG. 1 is a side view schematically showing a manufacturing apparatus used in the method for manufacturing a peelable piece of a resin thin film according to Embodiment 1 of the present invention. This manufacturing apparatus is an apparatus that performs steps (2) to (3) among steps (1) to (3) of the manufacturing method of the present invention. FIG. 2 is a cross-sectional view of a multilayer film used in this embodiment.
As shown in FIG. 1, an apparatus 100 for producing a peeled piece of a resin thin film used in this embodiment includes a feeding device 101 for feeding out a multilayer film 10, and a liquid is sprayed on the multilayer film 10 to form a crack to form a multilayer film. 10 includes a liquid spraying device 120 that peels the resin thin film from 10, a peeling chamber 110 that houses the liquid spraying device, and a peeling piece collection unit 115 that collects the peeled resin thin film 11 (peeling piece).

The feeding device 101 is a device for sending the multilayer film 10 manufactured in the step (1) at a desired delivery speed. A film roll obtained by winding the multilayer film 10 in the longitudinal direction can be attached to the feeding device 101. The feeding device 101 has a structure capable of feeding the multilayer film 10 in the longitudinal direction from the mounted film roll.
As shown in FIG. 2, the multilayer film 10 includes a base film 12 and a resin thin film 11 formed on the base film. In FIG. 1, the multilayer film 10 is transported so that the surface on the resin thin film 11 side is on the upper side when the multilayer film 10 is unwound from the unwinding apparatus 101 and is transported to the liquid spraying apparatus 120.

The multilayer film 10 fed from the feeding device 101 is transported in the direction indicated by A1 by the transport roll 102. As the transported multilayer film 10 is sprayed with a liquid, a crack is formed in the resin thin film 11 (step (2)).

Further, the resin thin film 11 is peeled off from the base film 12 by spraying a liquid further on the multilayer film 10 in which the crack is formed to obtain a peeled piece 11A (step (3)).

In the present embodiment, after a crack is formed in the resin thin film 11 in the peeling chamber 110, a liquid is further sprayed from the liquid spraying device 120 to a portion where the crack is formed, and the resin thin film 11 (peeling piece with the crack formed) is formed. 11A) is blown off and peeled off. The resin thin film 11 (peeled piece 11A) thus peeled moves to the peeled piece collection unit 115 together with the liquid. In the peeling piece collection unit 115, the peeling piece 11 </ b> A is collected from the liquid by the filter 116. Specifically, the peeling piece 11 </ b> A remains on the filter 116, and the liquid passes through the filter 116 and is recovered by the liquid recovery unit 130. The liquid recovered by the liquid recovery unit 130 can be discarded or reused through the liquid channel 131. The collected resin thin film 11 (peeling piece 11A) can be subjected to the next step depending on the application to be used.
Hereinafter, each step will be described in detail.

[2. Step (1)]
Step (1) is a step of forming a resin thin film on a base film to obtain a multilayer film. In the step (1), a composition containing a resin for forming a resin thin film is applied on a base film, and a film of the composition is provided. Then, the film of the composition is cured to form a resin thin film. A multilayer film can be manufactured by forming. Hereinafter, materials used in the step (1) and operations in the step (1) will be described.

[2.1. Base film]
The base film used for manufacturing the multilayer film is a film for supporting the resin thin film. This base film is preferably a film having a mechanical strength that is strong enough not to break in the step (2) of forming a crack in the resin thin film. Moreover, as a base film, a long film is preferable from a viewpoint that it can manufacture efficiently by the roll toe roll method.

As such a base film, a film having a base layer made of a resin can be used. Examples of the polymer contained in the resin that forms the base layer include: chain olefin polymer, cycloolefin polymer, polycarbonate, polyester, polysulfone, polyethersulfone, polystyrene, polyvinyl alcohol, cellulose acetate polymer, poly Examples thereof include vinyl chloride and polymethacrylate.

Here, as the resin, one containing one kind of polymer alone may be used, or one containing two or more kinds of polymers combined in an arbitrary ratio may be used. In addition, the resin may contain any compounding agent as long as the effects of the present invention are not significantly impaired.

The base film may be a single-layer film having only one layer, or may be a multilayer film having two or more layers. Accordingly, the base film may be a film including only the base layer, or may be a film including an arbitrary layer in addition to the base layer. For example, when using a liquid crystal composition as a composition for forming a resin thin film, the base film may have an alignment film from the viewpoint of satisfactorily aligning the liquid crystal composition.

The base film may have an orientation regulating force on the surface. Examples of the treatment for imparting the orientation regulating force to the base film include rubbing treatment, photo-alignment treatment, and alignment treatment by photolithography.
The rubbing treatment is a treatment for imparting an orientation regulating force by rubbing the surface of the film. In this case, the alignment film can be formed of a resin containing a polymer such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, and the like. Moreover, these polymers may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios. The alignment film can be manufactured by applying a solution containing the polymer, drying, and rubbing. In this case, the thickness of the alignment film is preferably 0.01 μm or more, more preferably 0.05 μm or more, preferably 5 μm or less, more preferably 1 μm or less.
However, when the orientation regulating force is applied to the base film, the base film may have an orientation film in addition to the base layer or may not have an orientation film. For example, a base film having an orientation regulating force can be obtained by directly rubbing the base layer.

The photo-alignment treatment is a treatment for imparting alignment regulating force by irradiating the light distribution film with linearly polarized ultraviolet rays and imparting anisotropy. The alignment process by photolithography is a process of forming a structure that exhibits an alignment regulating force on the surface of the base film using photolithography.

The base film may be a non-stretched unstretched film or a stretched stretched film.
Further, the base film may be an isotropic film or an anisotropic film.
Furthermore, the base film may have been subjected to surface treatment on one side or both sides. By performing the surface treatment, adhesion with other layers directly formed on the surface of the base film can be improved. Examples of the surface treatment include energy ray irradiation treatment and chemical treatment.

The thickness of the base film is preferably 1 μm or more, more preferably 5 μm or more, preferably 500 μm or less, more preferably 200 μm or less, from the viewpoints of handling properties at the time of manufacture, material cost, thickness reduction and weight reduction. is there.

[2.2. Resin thin film]
The resin thin film is a film formed on the surface of the base film with a resin. The resin thin film can be directly formed on the surface of the base film. Another layer may be provided between the base film and the resin thin film. The resin thin film may be a single-layer film having only one layer, or may be a multilayer film having two or more layers.

As the resin thin film, those having a small peel strength from the base film are preferable from the viewpoint of easily peeling the resin thin film from the base film. The specific peel strength between the base film and the resin thin film is preferably 500 N / m or less, more preferably 100 N / m or less, more preferably 10 N / m or less, and particularly preferably 5 N / m or less. The lower limit is not particularly limited, but is usually 1 N / m or more.

Here, the peel strength between the base film and the resin thin film can be measured by the following method.
Prepare a glass plate. Moreover, the adhesive sheet of a 3 layer structure provided with the peeling liner as a protective film, an adhesive layer, and a peeling liner in this order is prepared.
Cut the adhesive sheet to the same size as the glass plate. One release liner of the pressure-sensitive adhesive sheet is peeled to expose the surface of the pressure-sensitive adhesive layer. The exposed surface of the pressure-sensitive adhesive layer is bonded to a glass plate using a roller having a load of 1 kg.
The other release liner of the pressure-sensitive adhesive sheet is peeled off to expose the surface of the pressure-sensitive adhesive layer. The exposed surface of the pressure-sensitive adhesive layer is bonded to the surface on the resin thin film side of the multilayer film including the base film and the resin thin film using a roller having a load of 1 kg. Then, the part which protruded from the glass plate of a multilayer film is cut off. Thereby, the sample provided with a glass plate, an adhesive layer, a resin thin film, and a base film in this order is obtained.
The sample is sandwiched between jigs of a tensile tester (for example, “MX-500N-L550-E” manufactured by IMADA) and fixed. The base film of this sample is pulled in the 90 ° direction (that is, the normal direction of the surface of the glass plate) in accordance with JIS K6854-1, thereby peeling the base film from the resin thin film and measuring the peel strength. To do. The tensile speed during the measurement is 20 mm / min.

The thickness of the resin thin film is preferably 0.1 μm or more, more preferably 1 μm or more, particularly preferably 2 μm or more, preferably 200 μm or less, more preferably 100 μm or less, and particularly preferably 10 μm or less. By making the thickness of the resin thin film equal to or higher than the lower limit value, the base film is prevented from being damaged when forming a crack, and by making the thickness of the resin thin film equal to or lower than the upper limit value, the peeling work can be efficiently performed. .

As the resin thin film, for example, a film made of a cured product cured using a photocurable liquid crystal composition as a composition containing a resin can be used. That is, as the resin for forming the resin thin film, for example, a cured product of a photocurable liquid crystal composition can be used. A cured product of the photocurable liquid crystal composition is relatively brittle and tends to be easily broken by stress. Therefore, a film made of a cured product of a photocurable liquid crystal composition is suitable for the above-described method for manufacturing a release piece. Here, for convenience, a material referred to as a “liquid crystal composition” includes not only a mixture of two or more substances but also a material composed of a single substance.

Further, as the resin thin film, for example, a cholesteric resin layer may be used. The cholesteric resin layer refers to a resin layer having cholesteric regularity. The cholesteric regularity of the resin layer having the cholesteric regularity is that the molecular axes are aligned in a certain direction on one plane, but the direction of the molecular axis is slightly offset in the next plane that overlaps it, The structure is such that the angle of the molecular axis in the plane is shifted (twisted) as it sequentially passes through the overlapping planes so that the angle is further shifted in the next plane. That is, when the molecules in the layer have cholesteric regularity, the molecules are aligned in a manner that forms a layer of many molecules in the resin layer. In a certain layer A of the many molecular layers, the molecules are aligned such that the molecular axis is in a certain direction, and in the layer B adjacent thereto, the molecules are displaced at an angle from the direction in the layer A. Molecules are aligned in the direction, and in the layer C adjacent thereto, the molecules are aligned in a direction further at an angle with the direction in the layer B. In this way, in a large number of molecular layers, the angle of the molecular axes is continuously shifted to form a structure in which the molecules are twisted. Thus, the structure in which the direction of the molecular axis is twisted becomes an optically chiral structure.

The cholesteric resin layer usually has a circularly polarized light separation function. That is, it has a property of transmitting one circularly polarized light of right circularly polarized light and left circularly polarized light and reflecting a part or all of the other circularly polarized light. Moreover, the reflection in the cholesteric resin layer reflects circularly polarized light while maintaining its chirality. The cholesteric resin layer preferably has as high a reflectance as possible, and as a result, a layer having a high average reflectance in the wavelength range to be reflected is preferable. Thereby, when the peeling piece of the resin thin film is used as the material of the anti-counterfeit article, authenticity identification becomes clear. Moreover, when the peeling piece of a resin thin film is used as a material for a decorative article, the degree of freedom in design can be increased.

The wavelength that exhibits the circularly polarized light separation function generally depends on the pitch of the helical structure in the cholesteric resin layer. The pitch of the helical structure is the distance in the plane normal direction until the angle of the molecular axis in the helical structure is continuously shifted gradually as it advances along the plane, and then returns to the original molecular axis direction again. . By changing the pitch of the helical structure, the wavelength at which the circularly polarized light separating function is exhibited can be changed. The cholesteric resin layer capable of exhibiting a circularly polarized light separating function in a wide wavelength range includes, for example, (i) a cholesteric resin layer in which the pitch of the helical structure is changed stepwise, and (ii) the pitch of the helical structure. And a cholesteric resin layer in which is continuously changed.

When the cholesteric resin layer as described above is used as the resin thin film, the resin thin film peeling piece utilizing the circularly polarized light separation function can be efficiently manufactured by the manufacturing method of the present embodiment.

Hereinafter, a cholesteric resin layer made of a cured product of a photocurable liquid crystal composition will be described as an example of a suitable resin thin film. Such a cholesteric resin layer can be obtained, for example, by providing a film of a photocurable liquid crystal composition on a substrate film and curing the film of the liquid crystal composition. In this case, as the liquid crystal composition, for example, a composition containing a liquid crystal compound and capable of exhibiting a cholesteric liquid crystal phase when a film is formed on the base film can be used.

Here, as the liquid crystal compound contained in the liquid crystal composition, a polymerizable liquid crystal compound can be used. A non-liquid crystalline cholesteric resin layer cured by polymerizing the liquid crystalline compound having such polymerizability in a state exhibiting cholesteric regularity to cure the film of the liquid crystal composition and exhibiting cholesteric regularity. Can be obtained.

Preferred examples of such a liquid crystal composition include a liquid crystal composition containing a compound represented by the following formula (1) and a specific rod-like liquid crystal compound.

R ¹ -A ¹ -BA ² -R ² (1)
In the formula (1), R ¹ and R ² are each independently a linear or branched alkyl group having 1 to 20 carbon atoms, or a straight chain having 1 to 20 carbon atoms. Or a branched alkylene oxide group, a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a (meth) acryl group, an epoxy group, a mercapto group, an isocyanate group, an amino group, which may have an arbitrary linking group interposed, And a group selected from the group consisting of a cyano group.

The alkyl group and alkylene oxide group may be unsubstituted or substituted with one or more halogen atoms. Further, the halogen atom, hydroxyl group, carboxyl group, (meth) acryl group, epoxy group, mercapto group, isocyanate group, amino group, and cyano group are an alkyl group having 1 to 2 carbon atoms, and an alkylene oxide. It may be bonded to a group.

Preferred examples of R ¹ and R ² include a halogen atom, a hydroxyl group, a carboxyl group, a (meth) acryl group, an epoxy group, a mercapto group, an isocyanate group, an amino group, and a cyano group.

Moreover, it is preferable that at least one of R ¹ and R ² is a reactive group. By having a reactive group as at least one of R ¹ and R ^2, the compound represented by the formula (1) is fixed in the cholesteric resin layer at the time of curing, and a stronger layer can be formed. Here, examples of the reactive group include a carboxyl group, a (meth) acryl group, an epoxy group, a mercapto group, an isocyanate group, and an amino group.

In the formula (1), A ¹ and A ² are each independently 1,4-phenylene group, 1,4-cyclohexylene group, 1,4-cyclohexenylene group, 4,4′-biphenylene group, 4 , 4′-bicyclohexylene group and a group selected from the group consisting of 2,6-naphthylene group. 1,4-phenylene group, 1,4-cyclohexylene group, 1,4-cyclohexenylene group, 4,4′-biphenylene group, 4,4′-bicyclohexylene group, and 2,6-naphthylene group Is unsubstituted or substituted with one or more substituents such as a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, an amino group, an alkyl group having 1 to 10 carbon atoms, and a halogenated alkyl group. It may be. In each of A ¹ and A ² , when two or more substituents are present, they may be the same or different.

Particularly preferable examples of A ¹ and A ² include groups selected from the group consisting of 1,4-phenylene group, 4,4′-biphenylene group, and 2,6-naphthylene group. These aromatic ring skeletons are relatively rigid as compared with the alicyclic skeletons, have high affinity with the mesogen of the rod-like liquid crystal compound, and higher alignment uniformity.

In the formula (1), B is a single bond, —O—, —S—, —SS—, —CO—, —CS—, —OCO—, —CH ₂ —, —OCH ₂ —, —CH. = N-N = CH -, - NHCO -, - O- (C = O) -O -, - CH 2 - (C = O) -O-, and _{-CH 2 O- (C = O)} - from the Selected from the group consisting of
Particularly preferred examples of B include a single bond, —O— (C═O) —, and —CH═NN—CH—.

At least one of the compounds represented by the formula (1) preferably has liquid crystallinity, and preferably has chirality. In addition, the compound represented by the formula (1) is preferably used in combination of a plurality of optical isomers. For example, a mixture of a plurality of types of enantiomers, a mixture of a plurality of types of diastereomers, or a mixture of enantiomers and diastereomers may be used. At least one of the compounds represented by formula (1) preferably has a melting point in the range of 50 ° C to 150 ° C.

When the compound represented by the formula (1) has liquid crystallinity, the refractive index anisotropy Δn is preferably high. By using a liquid crystalline compound having a high refractive index anisotropy Δn as the compound represented by the formula (1), the refractive index anisotropy Δn of a liquid crystal composition containing the compound can be improved, and circularly polarized light is reflected. A cholesteric resin layer having a wide possible wavelength range can be produced. The refractive index anisotropy Δn of the compound represented by the formula (1) is preferably 0.18 or more, more preferably 0.22 or more. Here, the refractive index anisotropy Δn can be measured by the Senarmon method. For example, the cured resin layer is extinguished using an optical microscope (ECLIPSE E600POL (transmission / reflection type) with a sensitive color plate, λ / 4 wavelength plate, Senarmon compensator, GIF filter 546 nm, manufactured by Nikon Corporation). The retardation (Re) is calculated from the equation of Re = λ (546 nm) × θ / 180, and Δn is calculated from the thickness (d) of the liquid crystal layer obtained separately by the equation Δn = Re / d. it can.

Specific examples of particularly preferred compounds represented by the formula (1) include the following compounds (A1) to (A10). Moreover, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.

In the above compound (A3), “*” represents a chiral center.

The rod-like liquid crystalline compound used in combination with the compound represented by the formula (1) has a refractive index anisotropy Δn of 0.18 or more and at least two or more reactivities in one molecule. A rod-like liquid crystalline compound having a group is preferred. An example of such a rod-like liquid crystalline compound is a compound represented by the formula (2).
R ³ -C ³ -D ³ -C ⁵ -MC ⁶ -D ⁴ -C ⁴ -R ⁴ Formula (2)

In the formula (2), R ³ and R ⁴ are reactive groups, each independently (meth) acryl group, (thio) epoxy group, oxetane group, thietanyl group, aziridinyl group, pyrrole group, vinyl group. , An allyl group, a fumarate group, a cinnamoyl group, an oxazoline group, a mercapto group, an iso (thio) cyanate group, an amino group, a hydroxyl group, a carboxyl group, and an alkoxysilyl group. By having these reactive groups, a cured product having a film strength that can withstand practical use can be obtained when the liquid crystal composition is cured. Here, the film strength that can withstand practical use is pencil hardness (JIS K5400), which is usually HB or higher, preferably H or higher. By increasing the film strength in this way, it is difficult to damage the film, so that handling properties can be improved.

In the formula (2), D ³ and D ⁴ are a single bond, a linear or branched alkyl group having 1 to 20 carbon atoms, and a straight chain having 1 to 20 carbon atoms or Represents a group selected from the group consisting of branched alkylene oxide groups.

In the formula (2), C ³ to C ⁶ are a single bond, —O—, —S—, —S—S—, —CO—, —CS—, —OCO—, —CH ₂ —, —OCH _2. -, - CH = N-N = CH -, - NHCO -, - O- (C = O) -O -, - CH 2 - (C = O) -O-, and -CH ₂ O- (C = O) represents a group selected from the group consisting of:

In the formula (2), M represents a mesogenic group. Specifically, M is an azomethine group, azoxy group, phenyl group, biphenyl group, terphenyl group, naphthalene group, anthracene group, benzoic acid ester group, cyclohexanecarboxyl group, which may be unsubstituted or substituted. 2 to 4 skeletons selected from the group consisting of acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines, phenyldioxanes, tolanes, alkenylcyclohexylbenzonitriles, O—, —S—, —S—S—, —CO—, —CS—, —OCO—, —CH ₂ —, —OCH ₂ —, —CH═N—N═CH—, —NHCO—, — O- (C = O) -O - , - CH 2 - (C = O) -O-, and _{-CH 2 O- (C = O)} - represents a group bonded through by a linking group such as

Examples of the substituent that the mesogenic group M may have include a halogen atom, an optionally substituted alkyl group having 1 to 10 carbon atoms, a cyano group, a nitro group, —O—R ⁵ , — O—C (═O) —R ⁵ , —C (═O) —O—R ⁵ , —O—C (═O) —O—R ⁵ , —NR ⁵ —C (═O) —R ⁵ , —C (═O) —NR ⁵ R ⁷ , or —O—C (═O) —NR ⁵ R ⁷ may be mentioned. Here, R ⁵ and R ⁷ represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. When R ⁵ and R ⁷ are alkyl groups, the alkyl group includes —O—, —S—, —O—C (═O) —, —C (═O) —O—, —O—C. (═O) —O—, —NR ⁶ —C (═O) —, —C (═O) —NR ⁶ —, —NR ⁶ —, or —C (═O) — may be present. (However, the case where two or more of —O— and —S— are adjacent to each other is excluded). Here, R ⁶ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

Examples of the substituent in the “optionally substituted alkyl group having 1 to 10 carbon atoms” include, for example, a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, an amino group, and a carbon atom number of 1 to 6 alkoxy groups, alkoxyalkoxy groups having 2 to 8 carbon atoms, alkoxyalkoxyalkoxy groups having 3 to 15 carbon atoms, alkoxycarbonyl groups having 2 to 7 carbon atoms, 2 carbon atoms A 7 to 7 alkylcarbonyloxy group, an alkoxycarbonyloxy group having 2 to 7 carbon atoms, and the like.

The rod-like liquid crystal compound preferably has an asymmetric structure. Here, the asymmetric structure is a structure in which R ³ -C ³ -D ³ -C ⁵ -and -C ⁶ -D ⁴ -C ⁴ -R ⁴ are different in the formula (2) with the mesogenic group M as the center. Say. By using a rod-shaped liquid crystalline compound having an asymmetric structure, alignment uniformity can be further improved.

The refractive index anisotropy Δn of the rod-like liquid crystal compound is preferably 0.18 or more, more preferably 0.22 or more. When a rod-like liquid crystalline compound having a refractive index anisotropy Δn of 0.30 or more is used, the absorption edge on the long wavelength side of the ultraviolet absorption spectrum may extend to the visible region, but the absorption edge of the spectrum extends to the visible region. However, it can be used as long as the desired optical performance is not adversely affected. By using such a rod-like liquid crystalline compound having a high refractive index anisotropy Δn, a cholesteric resin layer having high optical performance (for example, selective reflection performance of circularly polarized light) can be obtained.

Preferred specific examples of the rod-like liquid crystalline compound include the following compounds (B1) to (B10). Moreover, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.

The weight ratio represented by (total weight of compounds represented by formula (1)) / (total weight of rod-like liquid crystalline compounds) is preferably 0.05 or more, more preferably 0.1 or more, and particularly preferably 0. .15 or more, preferably 1 or less, more preferably 0.65 or less, and particularly preferably 0.45 or less. By setting the weight ratio to be equal to or higher than the lower limit of the range, it is possible to improve alignment uniformity in the liquid crystal composition film. Further, by setting the upper limit value or less, the alignment uniformity can be increased. In addition, the stability of the liquid crystal phase of the liquid crystal composition can be increased. Furthermore, since the refractive index anisotropy Δn of the liquid crystal composition can be increased, a cholesteric resin layer having desired optical performance (for example, selective reflection performance of circularly polarized light) can be stably obtained. Here, the total weight indicates the weight when one type is used, and indicates the total weight when two or more types are used.

Moreover, when using the compound represented by Formula (1) and a rod-shaped liquid crystalline compound in combination, it is preferable that the molecular weight of the compound represented by Formula (1) is less than 600, and the molecular weight of a rod-shaped liquid crystalline compound is It is preferable that it is 600 or more. Thereby, since the compound represented by Formula (1) can enter into the gaps between the rod-like liquid crystal compounds having a higher molecular weight than that, the alignment uniformity can be improved.

The liquid crystal composition can optionally contain a cross-linking agent in order to improve the film strength and durability after curing. As a crosslinking agent, it reacts simultaneously when the film of the liquid crystal composition is cured, or a heat treatment is performed after curing to accelerate the reaction, or the reaction proceeds spontaneously by moisture, thereby increasing the crosslinking density of the cholesteric resin layer. Can be appropriately selected and used without causing deterioration in alignment uniformity. Therefore, for example, any cross-linking agent that is cured by ultraviolet rays, heat, moisture, or the like can be suitably used. Examples of the crosslinking agent include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 2- (2-vinyloxyethoxy). Polyfunctional acrylate compounds such as ethyl acrylate; epoxy compounds such as glycidyl (meth) acrylate, ethylene glycol diglycidyl ether, glycerin triglycidyl ether, pentaerythritol tetraglycidyl ether; 2,2-bishydroxymethylbutanol-tris [3- ( 1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane, trimethylolpropane-tri-β-aziridinylpropionate Aziridine compounds such as onate; Isocyanurate type isocyanate derived from hexamethylene diisocyanate, hexamethylene diisocyanate, biuret type isocyanate, adduct type isocyanate, etc .; Polyoxazoline compound having an oxazoline group in the side chain; Vinyltrimethoxysilane; N- (2-aminoethyl) 3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, N- (1 , 3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine and the like. Moreover, a crosslinking agent may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios. Furthermore, you may use a well-known catalyst according to the reactivity of a crosslinking agent. By using the catalyst, productivity can be improved in addition to the improvement of the film strength and durability of the cholesteric resin layer.

The amount of the crosslinking agent is preferably such that the amount of the crosslinking agent in the cholesteric resin layer obtained by curing the film of the liquid crystal composition is 0.1 wt% to 15 wt%. By setting the amount of the crosslinking agent to be not less than the lower limit of the above range, the crosslinking density can be effectively increased. Moreover, the stability of the film | membrane of a liquid-crystal composition can be improved by making it into an upper limit or less.

In addition, since the liquid crystal composition has photocurability, it usually contains a photoinitiator. As a photoinitiator, the well-known compound which generate | occur | produces a radical or an acid with an ultraviolet-ray or visible light can be used, for example. Specific examples of the photoinitiator include benzoin, benzylmethyl ketal, benzophenone, biacetyl, acetophenone, Michler's ketone, benzyl, benzylisobutyl ether, tetramethylthiuram mono (di) sulfide, 2,2-azobisisobutyronitrile, 2 , 2-azobis-2,4-dimethylvaleronitrile, benzoyl peroxide, di-tert-butyl peroxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-diethylthioxanthone, methylbenzoyl formate, , 2-diethoxyacetophenone, β-ionone, β-bromostyrene, diazoaminobenzene, α-amylcinnamic aldehyde, p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, 2-chlorobenzophenone, pp'-dichloro Benzophenone, pp'-bisdiethylaminobenzophenone, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin n-butyl ether, diphenyl sulfide, bis (2,6-methoxybenzoyl) -2,4,4-trimethyl-pentyl Phosphine oxide, 2,4,6-trimethylbenzoyldiphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, Anthracene benzophenone, α-chloroanthraquinone, diphenyl disulfide, hexachlorobutadiene, pentachlorobutadiene, octachlorobutene, 1-chloromethylnaphthalene, 1,2-octanedione-1- [4- (phenylthio) -2- (o- Benzoyloxime)] and 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] ethanone 1- (o-acetyloxime), (4-methylphenyl) [4- (2-Methylpropyl) phenyl] iodonium hexafluoroph Sufeto, 3-methyl-2-butynyl tetramethyl hexafluoroantimonate, diphenyl - (p-phenylthiophenyl) sulfonium hexafluoroantimonate, and the like. Moreover, these may be used individually by 1 type and may be used combining two or more types by arbitrary ratios. Furthermore, you may control sclerosis | hardenability using the tertiary amine compound as a well-known photosensitizer or a polymerization accelerator as needed.

The amount of the photoinitiator is preferably 0.03% to 7% by weight in the liquid crystal composition. By setting the amount of the photoinitiator to be equal to or higher than the lower limit of the above range, the degree of polymerization can be increased, so that the film strength of the cholesteric resin layer can be increased. Moreover, since the orientation of a liquid crystalline compound can be made favorable by setting it to the upper limit value or less, the liquid crystal phase of the liquid crystal composition can be stabilized.

The liquid crystal composition can optionally contain a surfactant. As the surfactant, for example, one that does not inhibit the orientation can be appropriately selected and used. As such a surfactant, for example, a nonionic surfactant containing a siloxane or a fluorinated alkyl group in the hydrophobic group portion is preferably exemplified. Of these, oligomers having two or more hydrophobic group moieties in one molecule are particularly suitable. Specific examples of these surfactants include PolyFox PF-151N, PF-636, PF-6320, PF-656, PF-6520, PF-3320, PF-651, PF-652 from OMNOVA; Neos FTX-209F, FTX-208G, FTX-204D of Surfactant, KH-40 of Surflon of Seimi Chemical Co., etc. can be used. Moreover, surfactant may be used individually by 1 type and may be used combining two or more types by arbitrary ratios.

The amount of the surfactant is preferably such that the amount of the surfactant in the cholesteric resin layer obtained by curing the liquid crystal composition is 0.05% by weight to 3% by weight. By setting the amount of the surfactant to be equal to or higher than the lower limit of the above range, the alignment regulating force at the air interface can be increased, so that alignment defects can be prevented. Moreover, by making it into the upper limit value or less, it is possible to prevent a decrease in alignment uniformity due to excessive surfactant entering between liquid crystal molecules.

The liquid crystal composition can optionally contain a chiral agent. Usually, the twist direction of the cholesteric resin layer can be appropriately selected depending on the type and structure of the chiral agent to be used. This can be realized by using a chiral agent that imparts dextrorotability when the twist is in the right direction, and by using a chiral agent that imparts levorotation when the twist direction is in the left direction. Specific examples of the chiral agent include JP-A-2005-289881, JP-A-2004-115414, JP-A-2003-66214, JP-A-2003-313187, JP-A-2003-342219, JP-A-2003-342219. Appropriate use can be made of those described in 2000-290315, JP-A-6-072962, U.S. Pat. No. 6,468,444, WO 98/00428, JP-A-2007-176870, and the like. For example, it is available as LC756 of BASF Corporation Paliocolor. Moreover, a chiral agent may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.

The amount of the chiral agent can be arbitrarily set within a range not deteriorating the desired optical performance. The specific amount of the chiral agent is usually 1% by weight to 60% by weight in the liquid crystal composition.

The liquid crystal composition may further contain other optional components as necessary. Examples of the optional component include a solvent, a polymerization inhibitor for improving pot life, an antioxidant for improving durability, an ultraviolet absorber, and a light stabilizer. Moreover, these arbitrary components may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios. The amount of these optional components can be arbitrarily set within a range that does not deteriorate the desired optical performance.

The method for producing the liquid crystal composition is not particularly limited, and can be produced by mixing the above-described components.

After preparing the photocurable liquid crystal composition, a film of the liquid crystal composition is provided on the base film. Usually, a film of a liquid crystal composition is provided by applying the liquid crystal composition to the surface of a base film. When the substrate film has an alignment film, a liquid crystal composition film is usually provided on the alignment film. Furthermore, before applying the liquid crystal composition, treatments such as corona discharge treatment and rubbing treatment may be applied to the surface of the base film as necessary.

The liquid crystal composition can be applied by a known method such as an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, a die coating method, or a bar coating method.

After providing the film of the liquid crystal composition on the base film, an alignment treatment may be performed as necessary. The alignment treatment can be performed, for example, by heating a liquid crystal composition film at 50 to 150 ° C. for 0.5 to 10 minutes. By performing the alignment treatment, the liquid crystal composition in the film can be aligned well.

Thereafter, a curing process is performed to cure the film of the liquid crystal composition. The curing process can be performed, for example, by a combination of one or more light irradiations and a heating process.
The heating conditions are, for example, usually 40 ° C. or higher, preferably 50 ° C. or higher, and usually 200 ° C. or lower, preferably 140 ° C. or lower, usually 1 second or longer, preferably 5 seconds or longer, and usually 3 minutes. Hereinafter, the time may be preferably 120 seconds or less.
Moreover, the light used for light irradiation includes not only visible light but also ultraviolet rays and other electromagnetic waves. The light irradiation can be performed, for example, by irradiating light having a wavelength of 200 nm to 500 nm for 0.01 second to 3 minutes. At this time, the energy of the irradiated light can be, for example, 0.01 mJ / cm ² to 50 mJ / cm ² .

A circle with a wide reflection band in which the pitch of the helical structure is continuously changed greatly by repeating the weak UV irradiation and heating of 0.01 mJ / cm ² to 50 mJ / cm ² alternately several times. A cholesteric resin layer having a polarization separation function can be obtained. Further, after the extension of the reflection band by weak ultraviolet irradiation, or the like described ^above was irradiated with a relatively strong ultraviolet such 50mJ / cm 2 ~ 10,000mJ / cm 2, by completely polymerizing the liquid crystalline compounds, A cholesteric resin layer having high mechanical strength can be obtained. The expansion of the reflection band and the irradiation with strong ultraviolet rays may be performed in the air, or a part or all of the process may be performed in an atmosphere in which the oxygen concentration is controlled (for example, in a nitrogen atmosphere). .

The step of applying and curing the liquid crystal composition as described above is not limited to once, and the application and curing may be repeated a plurality of times. Thereby, the cholesteric resin layer containing two or more layers can be formed. However, by using the liquid crystal composition described in the above example, a cholesteric resin layer containing a well-oriented rod-like liquid crystalline compound and having a thickness of 5 μm or more can be obtained by applying and curing the liquid crystal composition only once. Can be easily formed.

[2.3. Configuration of multilayer film]
The multilayer film 10 obtained in the step 1 can be configured as shown in FIG. This multilayer film 10 is subjected to step 2.

[3. Step (2)]
Step (2) is a step of forming a crack by spraying a liquid on the resin thin film.

Process (2) will be described with reference to FIGS. 1 and 3 described above. FIG. 3 is a cross-sectional view schematically showing a multilayer film in which cracks are formed by spraying a liquid.

The step of spraying the liquid onto the resin thin film is performed using a liquid spraying device 120 provided in the peeling chamber 110 as shown in FIG. The liquid spraying device 120 includes a liquid supply unit 121 and a nozzle 120A that sprays liquid. In the peeling chamber 110, a pair of tension rolls 111A and 111B capable of pressing the multilayer film 10 from one side in the thickness direction (the upper side in the figure) when the liquid is sprayed are provided rotatably in the circumferential direction. Further, the peeling chamber 110 is provided with a support plate 112 that is provided on the opposite side of the multilayer film 10 with respect to the tension rolls 111 </ b> A and 111 </ b> B and supports the multilayer film 10.

In the present embodiment, since the multilayer film 10 is pressed from above by the tension rolls 111A and 111B, the liquid is sprayed from the nozzle 120A provided above in a state where the lower surface is supported by the support plate 112. It is possible to perform the spraying work while preventing the film from sagging.

The pressure of the liquid sprayed from the nozzle 120A (spraying pressure) is set to such a high pressure that a crack is generated in the resin thin film 11 and the cracked resin thin film 11 can be blown off from the base film 12. The spray pressure of the liquid is preferably 0.15 MPa or more, more preferably 0.5 MPa or more, preferably 50 MPa or less, more preferably 40 MPa or less. By setting the spray pressure of the liquid to the lower limit value or more, a crack having a sufficient depth can be formed in the resin thin film, and the resin thin film can be peeled from the base film, and the spray pressure of the liquid is set to the upper limit value or less. This can prevent the base film from being damaged.

The installation direction of the nozzle 120A is set so that the resin thin film 11 can be peeled off by the liquid ejected from the nozzle 120A. The spray angle of the liquid with respect to the base film 12 can be an angle at which a crack can be formed in the resin thin film 11.

The liquid is not particularly limited, but tap water, ion exchange water, pure water; chloroform, methylene chloride, fluorocarbon and other (chlorine, fluorine, bromine) organic solvents; benzene, toluene, xylene and other aromatics Hydrocarbon solvents; aliphatic hydrocarbon solvents such as n-pentane, n-hexane, n-heptane; surfactants. These may be used alone or in combination of two or more. From the viewpoint of facilitating crack penetration and promoting the peeling of the resin thin film, a liquid selected from organic solvents, hydrocarbon solvents, and surfactants can be used. From the viewpoints of safe management, prevention of erosion of the resin thin film, and suppression of the occurrence of aggregation of the powder (peeling pieces), pure water is preferable. In the present application, “pure water” refers to water having a water quality equivalent to “A1” defined in JIS K0557 “Water used for water / wastewater tests” or higher.

Of the surfaces of the multilayer film 10, the surface on which the liquid is sprayed (the upper surface in the drawing) is the surface on which the resin thin film 11 is formed. When a liquid is sprayed on the surface of the multilayer film 10 on which the resin thin film is formed, the liquid collides with the resin thin film 11 and a crack 10C is formed. Thus, the multilayer film 10 in which the crack 10C is formed is obtained (see FIG. 2).

[Multilayer film with cracks formed in step (2)]
By performing the step (2), a crack 10C is formed in the resin thin film 11 of the multilayer film 10 as shown in FIG. The multilayer film 10 in which the crack 10C is formed is subjected to the step (3).

[4. Step (3)]
Step (3) is a step of peeling the resin thin film from the base film to obtain a peeled piece. In the present embodiment, the step (3) is a step (3A) of blowing the resin thin film in which the crack is formed from the base film by spraying the liquid onto the multilayer film in which the crack is formed, following the step (2). And a step (3B) of collecting the blown-off resin thin film.

In the present embodiment, the step (3A) of spraying a liquid onto the cracked multilayer film and blowing the resin thin film continues from step (2), and the same device (the liquid spraying device 120 provided in the peeling chamber 110). Can be used. In the step (3A), the liquid sprayed on the multilayer film is preferably the same liquid as the step (2) from the viewpoint of easy recovery, but may be different. The liquid spray pressure and the liquid spray angle in the step (3A) may be the same as or different from those in the step (2). That is, the step (3) may be performed as a separate step from the step (2), or may be performed simultaneously by the same operation as the step (2).

By continuing to spray the liquid from the step (2), the blown-off resin thin film 11 (peeling piece 11A) moves together with the liquid from the peeling chamber 110 to the peeling piece collecting unit 115 that is continuous. In the peel piece recovery unit 115, the filter 116 that can filter the peel piece 11A from the liquid is provided, and thus the peel piece 11A is recovered from the liquid. The stripped strip 11 </ b> A remains on the filter 116, and the liquid passes through the filter 116 and is recovered by the liquid recovery unit 130. The liquid recovered by the liquid recovery unit 130 moves in the direction indicated by L1 through the liquid channel 131 and can be discarded or reused. The resin thin film 11 (peeling piece 11A) recovered by the filter 116 can be subjected to the next step depending on the application to be used.

The base film 12 after the resin thin film 11 has been peeled is transported outside the peeling device 103 by the transport roll 103 and collected.

Since the resin thin film (peeling piece) collected by the filter may contain a liquid component, a drying process is performed as necessary. A drying process is normally performed using drying apparatuses, such as oven. The resin thin film (peeled piece) collected by the filter can be pulverized as it is or after performing a drying step. The resin thin film is usually pulverized using a pulverizer. Examples of the pulverizer include a ball mill, a bead mill, a roll mill, a rod mill, and a stone mill type pulverizer.

The average particle diameter of the peeled pieces of the resin thin film obtained by pulverization is preferably 1 μm or more for obtaining decorative properties, and preferably 500 μm or less for obtaining moldability and printability of the film. More preferably, it is 100 μm or less.

The average particle diameter of the peeled pieces of the resin thin film can be measured as follows. First, using several sieves having different openings, the ratio of the peeled pieces of the resin thin film passing through the sieve having the openings is measured. The particle size distribution of the resin thin film pigment is expressed as an integrated weight percentage from the size of the openings and the ratio of the peeled pieces of the resin thin film passing through the sieve having the openings. In this particle size distribution, the particle size having an integrated value of 50% by weight is defined as the average particle size.

[5. Application of resin thin film strips]
The peeled piece of the resin thin film manufactured by the manufacturing method described above can be applied to a paint as a pigment. This paint includes a dispersion medium and a release piece (pigment) of a resin thin film dispersed in the dispersion medium. Hereinafter, what applied the peeling piece of the resin thin film as a pigment is called a resin thin film pigment.

A layer containing a resin thin film pigment can be formed on the surface of the article by applying a coating containing the resin thin film pigment to the article and drying it. An article having a layer containing a resin thin film pigment can be used for various applications by taking advantage of the properties of the resin thin film pigment. For example, when the resin thin film is a cholesteric resin layer, the layer containing the resin thin film pigment produced from the resin thin film has a circularly polarized light separating function, like the resin thin film itself. Therefore, a film having a circularly polarized light separation function can be prepared on the surface of the article by using a paint manufactured using a resin thin film made of a cholesteric resin layer.

Examples of the application target of the layer containing the resin thin film pigment include anti-counterfeit articles, security articles, and decorative articles.
Examples of the anti-counterfeit article include a label for authenticity identification, a seal, and a display medium.
Examples of the security article include an authentication medium such as a cash voucher, a gift certificate, a ticket, a certificate, and a security card.
Examples of the decorative article include ornaments, stationery, furniture, automobiles (interior and exterior), home appliances, PCs, cosmetic packages, and the like.
In particular, when the resin thin film pigment has a circularly polarized light separating function, it is preferably applied to a display medium for authenticity identification.

[6. Action and effect of this embodiment]
According to this embodiment, since the resin thin film is peeled off from the base film after forming a crack, the resin thin film is easier than pulverizing the peeled resin thin film after peeling the resin thin film from the base film. It is possible to manufacture the peeling piece. Moreover, according to this embodiment, since a crack is formed and peeled in a resin thin film by spraying a liquid on a multilayer film, a manufacturing process can be simplified. As a result, according to the present embodiment, it is possible to provide a manufacturing method for efficiently manufacturing a peeling piece.
Furthermore, according to the present embodiment, the liquid is sprayed on the multilayer film to form a crack in the resin thin film, and the peeled peeled piece flows together with the sprayed liquid, so that the resin thin film is crushed dryly. In addition, the risk of dust explosion can be reduced, and the risk of clogging can be reduced.

[Other Embodiments]
In the above embodiment, a liquid spraying device including a nozzle 120A for spraying liquid from above into the peeling chamber 110, a pair of tension rolls 111A and 111B capable of pressing the multilayer film 10 from above in the thickness direction, and tension rolls 111A, Although 111B showed the aspect which has the support plate 112 provided in the other side in the thickness direction of the multilayer film 10, this invention is not limited to such an aspect. For example, the aspect shown in the following modified examples 1 and 2 may be sufficient.

(Modification 1)
In Embodiment 1, Modification 1 in which the arrangement position of the liquid spraying device and the arrangement position of the support plate are changed will be described with reference to FIG. FIG. 4 is a side view schematically showing a part of the manufacturing apparatus according to the first modification. As shown in FIG. 4, in the aspect of the first modification, the liquid spraying apparatus 200 including the nozzle 220 </ b> A capable of spraying the liquid L from the lower side in the drawing and a pair of tension rolls 211 </ b> A capable of pressing the multilayer film 10 from the upper side in the thickness direction. , 211B and a support plate 212 that supports the multilayer film 10 from the same direction as the tension roll. In the case of the said aspect, by arrange | positioning the multilayer film 10 so that the resin thin film 11 may become a lower side, a liquid is sprayed directly on the resin thin film 11, a crack is formed and it peels.

(Modification 2)
In Embodiment 1, Modification 2 in which the support plate is replaced with a roll-shaped support (support roll 310) will be described with reference to FIG. FIG. 5 is a side view schematically showing a part of the manufacturing apparatus according to the first modification. As shown in FIG. 5, in Modification 2, the peeling chamber does not include a tension roll, and includes a roll-shaped support 310 (support roll 310) as a support that supports the multilayer film 11. The support roll 310 is rotatable in the circumferential direction. The support roll 310 is provided in contact with the surface (lower surface) opposite to the surface (upper surface) to which the liquid L of the multilayer film 11 is sprayed, and the portion of the multilayer film 11 to which the liquid L is sprayed is provided. Support from below. In the case of this aspect, by arranging the multilayer film 10 so that the resin thin film 11 is on the upper side, the liquid is directly sprayed on the resin thin film 11 by the nozzle 320A provided above, and a crack is formed and peeled off. . In FIG. 5, 321 is a liquid supply part, 300 is a liquid spraying apparatus.

(Modification 3)
Modification 3 having a film transport path different from that of the first embodiment will be described with reference to FIG. FIG. 7 is a side view schematically showing a part of the manufacturing apparatus according to the third modification. In FIG. 7, the manufacturing apparatus 700 includes a feeding device 701 for feeding out the multilayer film 10, a liquid spraying device 720 for spraying a liquid on the multilayer film 10 to form a crack and peeling the resin thin film from the multilayer film 10, A peeling chamber 710 that houses the liquid spraying device and a peeling piece collection unit 115 that collects the peeled resin thin film 11 (peeling piece) are provided.

The feeding device 701 is a device for delivering the multilayer film 10 manufactured in the step (1) at a desired delivery speed. A film roll obtained by winding the multilayer film 10 in the longitudinal direction can be attached to the feeding device 701. The feeding device 701 has a structure capable of feeding the multilayer film 10 in the longitudinal direction from the attached film roll. In FIG. 7, when the multilayer film 10 is fed from the feeding device 701 and conveyed to the liquid spraying device 720, the surface on the resin thin film 11 side (see FIG. 2) is the nozzle 720A side (left side in FIG. 7). It is conveyed to become.

The multilayer film 10 fed from the feeding device 701 is conveyed in the direction indicated by the arrow A7 by an appropriate conveyance roll (not shown). The multilayer film 10 is conveyed in the direction of arrow A8 while being tensioned by a pair of tension rolls 711A and 711B and supported by the support plate 712 from the base film side (right side in FIG. 7). Then, it is provided to step (2) and step (3). In the steps (2) and (3), the liquid is supplied from the liquid supply unit 721 of the liquid spraying device 720 to the nozzle 720A, and the liquid is ejected from the nozzle 720A in the direction of the arrow A9. Spray. The resulting strip 11A and the liquid used are separated by the strip recovery unit 115, the filter 116, the liquid recovery unit 130, and other components by the same mechanism as in the first embodiment shown in FIG. Collected.

In Embodiment 1 shown in FIG. 1, both the tension rolls 111 </ b> A and 111 </ b> B and the liquid spraying device 120 are arranged on the resin thin film 11 side in the transport path of the multilayer film 10, whereas FIG. In Modification 3, spraying by the liquid spraying device 720 is performed on the resin thin film 11 side, while tension rolls 711A and 711B are disposed on the base film 12 side. In addition, in the first embodiment shown in FIG. 1, the tension rolls 111 </ b> A and 111 </ b> B are arranged horizontally, and the multilayer film 10 is conveyed horizontally between them, whereas the third modification shown in FIG. 7 is performed. Then, the tension rolls 711A and 711B are arranged substantially vertically, and the multilayer film 10 is conveyed substantially vertically between them.

By adopting such an arrangement and a transport direction, in Modification 3, it is possible to smoothly discharge and collect the liquid after spraying. That is, in the arrangement of the first embodiment, the liquid sprayed from the nozzle 120 can easily accumulate in the space surrounded by the multilayer film 10 and the tension rolls 111A and 111B. When such liquid accumulation occurs, there is a possibility that the energy of spraying from the nozzle 120 does not sufficiently reach the resin thin film. Further, there is a possibility that a trouble occurs in the transportation of the multilayer film 10 due to the accumulation of liquid. On the other hand, in the arrangement of the modified example 3, the liquid sprayed from the liquid spraying device 720 easily falls downward without being disturbed by the multilayer film 10 and the tension rolls 711A and 711B. Therefore, the liquid can be discharged and collected smoothly, and the peeling process can be performed smoothly. Such a feature can be a particularly advantageous effect when a long film having a particularly long length is used as the multilayer film 10 and the production method of the present invention is carried out continuously for a long time.

When the transport direction of the multilayer film at the time of spraying is substantially vertical, the vertical direction (gravity direction) can be 0 °, preferably 0-20 °, more preferably 5-15 °. When the transport direction is set to other than 0 ° and tilted from the vertical direction, it is preferable to tilt so that the surface on the resin thin film side is on the upper side. By setting it as such a conveyance direction, the peeling process can be performed smoothly and accumulation of liquid can be suppressed effectively.

In Modification 3, the multilayer film 10 is transported upward from the lower tension roll 711A to the upper tension roll 711B, and sprayed by blowing liquid downward from the liquid spraying device 720. The direction of conveyance and spraying is not limited to this. For example, the liquid may be conveyed downward and the liquid may be blown upward and sprayed. However, it is advantageous to carry out the conveyance upward from the lower side in order to carry out stable conveyance. Specifically, when the film is conveyed upward and tension is applied to the multilayer film 10, a force is applied in a direction of pulling the multilayer film 10 upward. As a result, it is possible to reduce the tendency of the multilayer film 10 to bend in the operation of spraying, compared to the case of transporting in the reverse direction.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples.
In the following description, “%” and “parts” representing amounts are based on weight unless otherwise specified. In addition, the operations described below were performed under normal temperature and normal pressure conditions unless otherwise specified.

[Explanation of reagents]
The reagents used in the following examples are as follows.

As the photopolymerizable liquid crystalline compound 1, a compound having the following structure was used.

As the photopolymerizable liquid crystalline compound 2, a compound having the following structure was used.

As the photopolymerizable non-liquid crystalline compound, a compound having the following structure was used.

As the chiral agent, “LC756” manufactured by BASF Corporation was used.
As a photopolymerization initiator, “Irgacure OXEO2” manufactured by Ciba Japan was used.
As the surfactant, “Factent 209F” manufactured by Neos Co., Ltd. was used.

The following were used as the liquid.
・ Pure water (purified water made by TRUSCO, water quality equivalent to "A1" or higher specified in JISK0557)

[Evaluation methods]
(Measurement method of peel strength of resin thin film from base film)
A glass plate (size: 25 mm width × length 100 mm, thickness 2 mm) was prepared. Further, an adhesive sheet (“LUCIACS CS9621T” manufactured by Nitto Denko, thickness of 25 μm) was cut into the same size as this glass plate. This pressure-sensitive adhesive sheet was a film having a three-layer structure including a release liner as a protective film, a pressure-sensitive adhesive layer, and a release liner in this order.

The one release liner of the pressure-sensitive adhesive sheet was peeled off to expose the surface of the pressure-sensitive adhesive layer. The exposed surface of the pressure-sensitive adhesive layer was bonded to a glass plate using a roller having a load of 1 kg.

The other release liner of the pressure-sensitive adhesive sheet was peeled off to expose the surface of the pressure-sensitive adhesive layer. The exposed surface of the pressure-sensitive adhesive layer was bonded to the surface on the resin thin film side of the multilayer film including the base film and the resin thin film, using a roller with a load of 1 kg. Then, the part which protruded from the glass plate of a multilayer film was cut off. Thereby, the sample provided with a glass plate, an adhesive layer, a resin thin film, and a base film in this order was obtained.

The sample was sandwiched between fixtures of a tensile testing machine (“MX-500N-L550-E” manufactured by IMADA) and fixed. By pulling the base film of this sample in the direction of 90 ° according to JIS K6854-1 (that is, the normal direction of the surface of the glass plate), the base film is peeled from the resin thin film, and the peel strength is measured. did. In the measurement, a load cell having a maximum load of 5N was used. Further, the tensile speed during the measurement was 20 mm / min.

(Evaluation of particle size of the peeled piece of resin thin film)
By visual observation, the particle size of the peeled piece obtained in each example was compared with the particle size of the peeled piece obtained in Comparative Example 1, and evaluated by the following criteria.
“Good”: The particle size of most of the peeled pieces is smaller than the particle size of the peeled piece of Comparative Example 1.
“Bad”: The particle size of most of the peeled pieces is equal to or larger than the particle size of the peeled piece of Comparative Example 1.

(Evaluation of peeling speed of resin thin film peeling piece)
By transporting fluid (liquid or gas) to the cracked portion of the resin thin film, the transport speed of the multilayer film when the entire amount of the resin thin film was peeled was compared.

(Evaluation of continuous processing time)
The resin thin film was peeled well at 60 minutes and 150 minutes after the start of the production of the resin thin film release piece (continuous step (2) and step (3)). It was determined whether or not. As a result of the determination, when it was determined that the resin thin film was peeled well, the operation of the apparatus was continued as it was. When it was determined that the resin thin film was not peeled well, the operation of the apparatus was interrupted, the apparatus was cleaned, and then the operation was resumed.
The result of determination was evaluated according to the following evaluation criteria.
60: It was determined that peeling of the resin thin film was not performed well 60 minutes after the start of production.
150: It was determined that the resin thin film was peeled well 60 minutes after the start of production, but it was determined that the resin thin film was not peeled well 150 minutes after the start of production.
> 150: It was determined that the resin thin film was peeled well both 60 minutes after the start of production and 150 minutes after the start of production.

[Example 1]
(1-1. Preparation of Photocurable Liquid Crystal Composition)
Photopolymerizable liquid crystal compound 1, photopolymerizable non-liquid crystal compound, chiral agent, photopolymerization initiator, surfactant and cyclopentanone were mixed at the ratio shown in Table 1 to obtain a photocurable liquid crystal composition. Prepared.

(1-2. Production of long multilayer film)
A long polyethylene terephthalate film (“PET film A4100” manufactured by Toyobo Co., Ltd .; thickness 100 μm) having an in-plane refractive index isotropic and having an in-plane refractive index was prepared as a base film. This base film was attached to the feeding part of the film transport apparatus, and the following operations were performed while transporting the base film in the longitudinal direction. First, the rubbing process was performed in the longitudinal direction parallel to the transport direction. Next, the liquid crystal composition prepared in (1-1) was applied to the surface subjected to the rubbing treatment using a die coater. Thereby, the film | membrane of the uncured liquid crystal composition was formed in the single side | surface of a base film.

The film of the obtained liquid crystal composition is subjected to an alignment treatment at 100 ° C. for 5 minutes, and the film is irradiated with weak ultraviolet rays of 0.1 mJ / cm ² to 45 mJ / cm ² , followed by 1 at 100 ° C. The process consisting of a minute warming treatment was repeated twice. Thereafter, the liquid crystal composition film was irradiated with ultraviolet rays of 800 mJ / cm ² in a nitrogen atmosphere to completely cure the liquid crystal composition film. Thereby, the multilayer film provided with the resin thin film of the thickness shown in Table 1 on the single side | surface of a elongate base film was obtained. About the obtained multilayer film, the peeling strength of the resin thin film from a base film was measured by the method mentioned above.

(1-3. Manufacture of peeling piece of resin thin film)
An apparatus 100 having a feeding device 101, a peeling chamber 110, a liquid spraying device 120, a peeling piece collecting unit 115, and a liquid collecting unit 130 shown in FIG. 1 was prepared.

The resin thin film 11 was placed on the upper side of the feeding device 101, the multilayer film 10 was attached, and the film was conveyed at the line speed shown in Table 1, and the following operations were performed. Pure water was used as the liquid, the spraying pressure was set to 30 MPa, and sprayed from the nozzle 120 </ b> A to the upper surface side of the multilayer film 10. The conveyance direction of the multilayer film at the time of spraying was set to the horizontal direction as shown in FIG.

When the liquid was sprayed, a crack occurred in the resin thin film immediately after the spraying started. Then, when the liquid was further sprayed on the multilayer film 10, the resin thin film 11 in which the crack was formed peeled off and was blown off by the liquid. In this example, since the multilayer film 10 was conveyed at a line speed of 20 m / min, the liquid spraying time was 0.2 seconds, but at the time immediately after the start of operation of the apparatus, the entire amount of the resin thin film 11 was peeled off. Thereafter, the operation of the apparatus was continued and the continuous processing time was evaluated.

Thereafter, the peeled piece 11A of the obtained resin thin film 11 was recovered from the liquid by the filter 116. The collected peeled pieces 11A were dried with a dryer, the size of the obtained peeled pieces was visually observed, and the particle size of the peeled pieces was evaluated according to the evaluation criteria described above.

[Example 2]
Except that the composition of the liquid crystal composition was changed as shown in Table 1 in step (1-1), the same procedure as in Example 1 was performed to produce a release piece. The magnitude | size of the obtained peeling piece was observed visually, and the particle size of the peeling piece was evaluated.
Also in this example, when the liquid was sprayed, a crack occurred in the resin thin film immediately after the spraying started. Then, when the liquid was further sprayed on the multilayer film 10, the resin thin film 11 in which the crack was formed peeled off and was blown off by the liquid. In this example, since the multilayer film 10 was conveyed at a line speed of 20 m / min, the liquid spraying time was 0.2 seconds, but at the time immediately after the start of operation of the apparatus, the entire amount of the resin thin film 11 was peeled off. Thereafter, the operation of the apparatus was continued and the continuous processing time was evaluated.

[Example 3]
After the multilayer film obtained in (1-2) of Example 1 was roll-pressed using a press apparatus (roll press apparatus SA-602 manufactured by Tester Sangyo Co., Ltd.) at a press pressure of 30 MPa and a press time of 0.06 seconds, Except that the operation (1-3) of Example 1 was performed, the same operation as in Example 1 was performed to produce a peeled piece, and the size of the obtained peeled piece was visually observed, Particle size was evaluated.
In this example, a crack is generated in the resin thin film by pressing, and when the liquid is sprayed after pressing, more cracks are generated. By spraying the liquid further, the resin thin film 11 having the crack is peeled off and blown away by the liquid. It was done. In this example, since the multilayer film 10 was conveyed at a line speed of 20 m / min, the liquid spraying time was 0.2 seconds, but at the time immediately after the start of operation of the apparatus, the entire amount of the resin thin film 11 was peeled off. Thereafter, the operation of the apparatus was continued and the continuous processing time was evaluated.

[Example 4]
Except for the following changes, the same operation as in Example 1 was performed to produce a peeled piece, and the evaluation of the continuous treatment time of the apparatus and the particle size of the peeled piece were performed.
In the step (1-3), instead of the apparatus 100, the apparatus 700 shown in FIG. 7 is used as the apparatus, and the transport direction of the multilayer film at the time of spraying is as shown in FIG. It was.
In step (1-3), the set pressure for spraying was changed from 30 MPa to 20 MPa.

[Example 5]
Except for the following changes, the same operation as in Example 1 was performed to produce a peeled piece, and the evaluation of the continuous treatment time of the apparatus and the particle size of the peeled piece were performed.
In step (1-1), the composition of the liquid crystal composition was changed as shown in Table 1.
In the step (1-3), instead of the apparatus 100, the apparatus 700 shown in FIG. 7 is used as the apparatus, and the transport direction of the multilayer film at the time of spraying is as shown in FIG. It was.
In step (1-3), the set pressure for spraying was changed from 30 MPa to 20 MPa.

[Comparative Example 1]
Using the multi-layer film produced in (1-2) of Example 1 and using the production apparatus shown in FIG. 6, a peeled piece of the resin thin film was produced by the following method. The obtained peeling piece was used as a comparison object for evaluating the particle size of the peeling piece of the example.

(Manufacture of peeling pieces of resin thin film)
FIG. 6 is a side view schematically showing a peeling piece manufacturing apparatus used in Comparative Example 1. FIG. As shown in FIG. 6, the manufacturing apparatus 400 provided with the film delivery part 420, the peeling part 430, and the film collection | recovery part 440 was prepared. The peeling portion 430 was provided with a bar 434 having a corner portion 435 provided at an acute angle, and a nozzle 436 capable of injecting air provided immediately downstream of the corner portion 435. At this time, the angle of the corner portion 435 of the bar 434 was set so that the multilayer film 10 could be folded back at an angle θ (60 °). The corner portion has a chamfered structure of R = 0.2 mm to 0.3 mm.

The multilayer film 10 was attached to the film delivery section 420 in such a direction that the multilayer film 10 could be folded back with the resin thin film 11 outside the base film 12 at the corner portion 435 of the bar 434. And the multilayer film 10 was sent out from the film delivery part 420 in the state which gave the tension | tensile_strength in the conveyance direction with respect to the multilayer film 10 by the film collection | recovery part 440. FIG. At this time, the magnitude of the tension applied to the multilayer film 10 was set to 80 N / m. Air was injected from the nozzle 436 at a pressure of 0.5 MPa.

The multilayer film 10 was folded at the corner portion 435 of the bar 434, and many cracks were formed. Thereafter, the resin thin film 11 with cracks formed was peeled off and blown off by the air jetted from the nozzle 436, and a peeled piece 11A was obtained. When the multilayer film 10 was conveyed at a line speed of 20 m / min, only a part of the resin thin film having cracks could be peeled off. Therefore, when the multilayer film 10 is transported at a line speed of 10 m / min, 5 m / min, and 1 m / min, by transporting at a line speed of 1 m / min, the total amount in the width direction of the cracked resin thin film is reduced. It peeled.

The evaluation results of the above examples are shown in Table 1 below.

[result]
As shown in Table 1, according to Examples 1 to 5, it is possible to provide a method for producing a peeling piece of a resin thin film formed on a base film, which can efficiently produce the peeling piece. did it.
In Examples 4 and 5, although the spraying pressure was set to a pressure lower than that of the other examples, the particle size evaluation equivalent to that of the other examples can be obtained, and the continuous treatment can be performed for a longer time. did it. Therefore, it can be seen that particularly advantageous production can be performed by spraying in the upward conveyance performed in Examples 4 and 5.

DESCRIPTION OF SYMBOLS 10 ... Multilayer film 10C ... Crack 11 ... Resin thin film 11A ... Stripping piece 12 ... Base film 100 ... Manufacturing apparatus 101 of peeling piece of resin thin film ... Feeding apparatus 102, 103 ... Conveyance roll 110 ... Stripping chamber 111A, 111B, 211A 211B ... Tension roll 112 ... Support plate 115 ... Peeling piece collection unit 116 ... Filters 120, 200, 300 ... Liquid spraying devices 120A, 220A, 320A ... Nozzles 121, 221, 321 ... Liquid supply unit 130 ... Liquid collection unit 131 ... Liquid flow path 310 ... support roll L ... liquid L1 ... liquid moving direction 700 ... manufacturing apparatus 701 ... feeding apparatus 710 ... peeling chamber 711A, 711B ... tension roll 720 ... liquid spraying apparatus 720A ... nozzle 721 ... liquid supply section

Claims (7)

1. Forming a resin thin film on the base film to obtain a multilayer film (1);
   (2) forming a crack by spraying a liquid on the resin thin film;
   And (3) obtaining a peeled piece by peeling the resin thin film from the base film.
   A method for producing a peeled piece of a resin thin film.
2. The method for producing a peeled piece of a resin thin film according to claim 1, wherein the liquid is pure water.
3. The method for producing a peeled piece of a resin thin film according to claim 1 or 2, wherein the step (2) is performed at a spraying pressure of 0.15 MPa to 50 MPa.
4. The method for producing a peeled piece of a resin thin film according to any one of claims 1 to 3, wherein the resin thin film comprises a cured product of a photocurable liquid crystal composition.
5. The method for producing a peeled piece of a resin thin film according to any one of claims 1 to 4, wherein the resin thin film is a cholesteric resin layer.
6. The method for producing a peelable piece of a resin thin film according to any one of claims 1 to 5, wherein the peel strength between the base film and the resin thin film is 500 N / m or less.
7. The method for producing a peeled piece of a resin thin film according to any one of claims 1 to 6, wherein the thickness of the resin thin film is 0.1 μm or more and 200 μm or less.

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