JP2019104799A - Peeling agent composition and peeling sheet - Google Patents

Abstract

To provide a peeling agent composition that makes it possible to form a peeling layer excellent in both of peelability and residual adhesion rate.SOLUTION: The present invention provides a peeling agent composition containing a polyolefin (A) having a crosslinkable functional group as the main agent and a polyrotaxane compound (B) and a crosslinker (C).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a release agent composition and a release sheet.

In general, the release sheet has a substrate, such as, for example, paper, plastic film, or polyethylene laminated paper, and a release layer provided on the substrate. The release layer is formed by applying and curing a release agent composition containing a reactive compound on a substrate.
The release sheet is widely used as, for example, a protective sheet for a pressure-sensitive adhesive layer possessed by a pressure-sensitive adhesive sheet or the like, a process film for producing a resin sheet, a process film for forming a ceramic green sheet, and a process film for producing a synthetic leather.

As a release agent composition for forming a release layer, a silicone type release agent composition containing a silicone compound such as a silicone resin, a siloxane, or a silicone oil is widely used.
However, the silicone compound may migrate to the contact surface with the release layer, for example, the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive sheet. In addition, after the transition, it may be gradually vaporized.
Therefore, when a release sheet having a release layer formed of a silicone-based release agent composition is used in an electronic material application, the silicone compound may be transferred to the electronic component, which may cause corrosion or malfunction of the electronic component.

  Therefore, studies have been conducted to form a release layer without using a silicone release agent composition. For example, Patent Document 1 describes a release sheet having a release layer formed of a release agent composition containing at least a polyolefin, an isocyanate having three or more isocyanate groups in one molecule, and a polyolefin polyol.

JP, 2011-52207, A

However, the release layer formed of a release agent composition other than the silicone release agent composition tends to be deteriorated in the releasability.
In addition, when the formulation of the release agent composition is adjusted to reduce the release force of the release layer, the residual adhesion rate of the release layer may be reduced.
The “residual adhesion rate” is the ratio of the adhesive strength of the pressure-sensitive adhesive layer before and after the pressure-sensitive adhesive layer of the standard pressure-sensitive adhesive sheet is laminated on the release layer, and the transition component in the release layer is the other layer. It is an indicator of the amount of transition to Specifically, it is measured by the method described in detail in the examples described later.

  Then, an object of this invention is to provide the release agent composition which can form the peeling layer which is excellent in peelability and shows a high residual adhesion rate.

  The present inventors have found that a release agent composition containing a polyolefin having a crosslinkable functional group as a main agent and containing a polyrotaxane compound and a crosslinking agent can solve the above-mentioned problems.

That is, the present invention relates to the following [1] to [5].
[1] A release agent composition comprising a polyolefin (A) having a crosslinkable functional group as a main ingredient, and containing a polyrotaxane compound (B) and a crosslinking agent (C).
[2] The release agent composition according to the above [1], wherein the crosslinkable functional group possessed by the polyolefin (A) is a hydroxyl group.
[3] The release agent composition according to the above [1] or [2], wherein the polyolefin skeleton of the polyolefin (A) is a hydrogenated substance of polyolefin.
[4] The release agent composition according to any one of the above [1] to [3], wherein the crosslinking agent (C) is a melamine compound.
[5] A release sheet comprising a substrate and a release layer formed of the release agent composition according to any one of the above [1] to [4].

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the release agent composition which can form the peeling layer which is excellent in peelability and shows a high residual adhesion rate.

It is a schematic sectional drawing of the peeling sheet of 1 aspect of this invention.

In the present specification, the number average molecular weight (Mn) and the mass average molecular weight (Mw) are values in terms of standard polystyrene measured by gel permeation chromatography (GPC).
Moreover, in this specification, an "active ingredient" refers to the component except the dilution solvent among the components contained in a release agent composition.
In the following description, “content of each component relative to the total amount of the active ingredient in the release agent composition” should be regarded as “content of each component in the release layer formed from the release agent composition” You can also.

[Release agent composition]
The release agent composition of the present invention contains a polyolefin (A) having a crosslinkable functional group as a main ingredient, and contains a polyrotaxane compound (B) and a crosslinking agent (C). In the following description, "polyolefin (A) having a crosslinkable functional group" may be abbreviated as "polyolefin (A)".

The present inventors conducted various studies on formulations for reducing the peel strength of the release layer formed from the release agent composition, for release agent compositions other than silicone release agent compositions. As a result, the present inventors crosslink to the polyolefin (A) having the crosslinkable functional group in the release agent composition which contains the polyolefin (A) having the crosslinkable functional group as a main agent and the crosslinker (C). By reducing the compounding ratio of an agent (C), it discovered that the peeling force of a peeling layer fell.
However, on the other hand, it has been found that there may be a problem that the residual adhesion rate of the release layer is lowered.
When the release layer having a low residual adhesion rate is brought into contact with the adherend, the release agent component is easily transferred to the adherend. Therefore, if the adherend is a pressure-sensitive adhesive layer, the adhesion of the pressure-sensitive adhesive layer may be reduced by the migration of the release agent component.
The present inventors solved the above problems by a release agent composition containing the polyolefin (A) having a crosslinkable functional group as a main ingredient and containing the polyrotaxane compound (B) and the crosslinking agent (C). It has been found that the present invention can be achieved.

  The release agent composition of one embodiment of the present invention may contain additives other than the components (A), (B) and (C) described above, as long as the effects of the present invention are not impaired.

  In the release agent composition of one embodiment of the present invention, the total content of the components (A), (B), and (C) described above is preferably 70 based on the total amount (100% by mass) of the release agent composition. The content is preferably at least 80% by mass, more preferably at least 90% by mass, and still more preferably at least 95% by mass.

The release agent composition of the present invention contains a polyolefin (A) having a crosslinkable functional group as a main ingredient.
In the present specification, the "main agent" means a component having the largest content (mass ratio) in the release agent composition, and preferably 50 based on the total amount (100% by mass) of the release agent composition. It means a component that occupies% by mass or more.
In the release agent composition according to one aspect of the present invention, a polyolefin (A) having a crosslinkable functional group from the viewpoint of forming a release layer more excellent in release property and from the viewpoint of further improving the residual adhesion rate of the release layer. The content is preferably 55 to 90% by mass, more preferably 60 to 85% by mass, and still more preferably 65 to 80% by mass, based on the total amount (100% by mass) of the release agent composition.

  In the release agent composition of one aspect of the present invention, the viewpoint of forming a release layer more excellent in release property, the viewpoint of further improving the residual adhesion rate of the release layer, and the solvent resistance of the release layer is made favorable. From the viewpoint of making the compatibility with the components (A) and (C) good, the content of the polyrotaxane compound (B) is preferably based on the total amount (100% by mass) of the release agent composition. The content is 2 to 29% by mass, more preferably 4 to 20% by mass, and still more preferably 8 to 20% by mass.

  In the release agent composition of one aspect of the present invention, a viewpoint of forming a release layer more excellent in release property, a viewpoint of further improving the residual adhesion rate of the release layer, and a good solvent resistance of the release layer. In view of the above, the content of the crosslinking agent (C) is preferably 7 to 20% by mass, more preferably 7 to 15% by mass, and still more preferably 8 to 20% by mass, based on the total amount (100% by mass) of the release agent composition. It is 12% by mass.

  In the release agent composition according to one aspect of the present invention, the content of polyrotaxane compound (B) is preferably 1 to 50 parts by mass, more preferably 6 to 29 based on 100 parts by mass of polyolefin (A) having a crosslinkable functional group. It is a mass part, More preferably, it is 13-29 mass parts.

  In the release agent composition according to one aspect of the present invention, the content of the crosslinking agent (C) relative to 100 parts by mass of the polyolefin (A) having a crosslinkable functional group is preferably 11 to 17 parts by mass, more preferably 12 to 14 It is a mass part, More preferably, it is 13-14 mass parts.

  In the release agent composition according to one aspect of the present invention, the content of the crosslinking agent (C) relative to the polyrotaxane compound (B) is preferably 1/10 to 30/10, more preferably 5/10 to 20/10, and further preferably Preferably, it is 10/10 to 20/10.

  In the release agent composition according to one aspect of the present invention, the polyrotaxane compound (B) is equivalent to the crosslinker (C) in the magnitude relation between the content (mass) of the polyrotaxane compound (B) and the content (mass) of the crosslinking agent (C). The amount is preferably larger than the crosslinking agent (C), and more preferably the polyrotaxane compound (B) is larger than the crosslinking agent (C).

  Hereinafter, each component contained in the release agent composition of this invention is demonstrated.

<Polyolefin having crosslinkable functional group (A)>
The polyolefin (A) having a crosslinkable functional group is not particularly limited as long as it is a polyolefin having one or more crosslinkable functional groups.
In the present specification, the "crosslinkable functional group" means a functional group having reactivity with the crosslinking agent (C).

The crosslinkable functional group possessed by the polyolefin (A) is selected in relation to the crosslinker (C).
As a crosslinkable functional group which polyolefin (A) has, a hydroxyl group, a carboxyl group, an epoxy group, an amino group, an isocyanate group, a thiol group, a vinyl group etc. are mentioned, for example.
Among these, the crosslinkable functional group is preferably a hydroxyl group from the viewpoint of making the reactivity with the crosslinking agent (C) better.
Moreover, it is preferable that polyolefin (A) has two or more crosslinkable functional groups. When the polyolefin (A) has two or more crosslinkable functional groups, these functional groups may be the same as or different from each other, but are preferably the same as each other.

As the polyolefin skeleton constituting the polyolefin (A), for example, one or more selected from α-olefins such as ethylene, propylene and 4-methylpentene, and conjugated dienes such as isoprene and butadiene are polymerized Or hydrogenated products of these polymers or copolymers.
The polyolefin skeleton may have only one selected from these, or may have two or more.
Moreover, when the polyolefin skeleton has a copolymer composed of two or more structural units, the form of the copolymer is not particularly limited, and block copolymers, random copolymers, and graft copolymers It may be any.
Here, in the release agent composition according to one aspect of the present invention, the polyolefin skeleton possessed by the polyolefin (A) is from the viewpoint of forming a release layer having better release properties and improving the residual adhesion rate of the release layer, It is preferable to be a hydrogenated substance of polyolefin, more preferable to be a hydrogenated substance of polybutadiene, and it is preferable to be a hydrogenated substance of polybutadiene. The hydrogenated substance may be a partially hydrogenated substance or a completely hydrogenated substance, but is preferably a completely hydrogenated substance.

The position of the crosslinkable functional group possessed by the polyolefin (A) is not particularly limited as long as the crosslinkable functional group can react with the crosslinker (C).
Here, in the release agent composition according to one aspect of the present invention, at least one end of molecular chains constituting the polyolefin skeleton from the viewpoint of forming a release layer having a more excellent release property by increasing the distance between crosslinking points. It is preferable to have a crosslinkable functional group, and it is more preferable to have a crosslinkable functional group at both ends of a molecular chain constituting a polyolefin skeleton, and a crosslinkable functional group only at both ends of a main chain constituting a polyolefin skeleton. It is more preferable to have.

  In addition, polyolefin (A) may be used individually by 1 type, and may be used in combination of 2 or more type.

The number average molecular weight ( _Mn ) of the polyolefin (A) is preferably 1,500 to 30,000, more preferably 2,000 to 20,000, and still more preferably 2,000 to 10,000.

<Polyrotaxane Compound (B)>
The polyrotaxane compound (B) is a compound in which a linear molecule penetrates the opening of at least two cyclic molecules and has a blocking group at both ends of the linear molecule.
In the polyrotaxane compound (B), a cyclic molecule can freely move along a linear molecule, but the blocking group has a structure in which the cyclic molecule can not escape from the linear molecule. That is, the cyclic molecule is not bound and fixed to the linear molecule by a chemical bond such as a covalent bond, but does not fall off from the linear molecule due to the presence of block groups at both ends of the linear molecule. , Can move freely along the linear molecule.

The cyclic molecule constituting the polyrotaxane compound (B) is not particularly limited as long as it has an opening through which the linear molecule can penetrate. Preferred cyclic molecules include cyclic oligosaccharides. The use of cyclic oligosaccharides as cyclic molecules allows the selection of an appropriate ring diameter. Thereby, the effect by moving the cyclic molecule along the linear molecule is likely to be exhibited. Furthermore, introduction of various substituents and the like is also easy, which makes it possible to adjust the compatibility of the polyrotaxane compound (B) with other components by the polyrotaxane compound (B). Furthermore, cyclic oligosaccharides have the advantage of being easily available.
In the present specification, "cyclic" of "cyclic molecule" or "cyclic oligosaccharide" means substantially "cyclic". That is, as long as it can move along a linear molecule, the cyclic molecule may not be completely closed, for example, may have a helical structure.

Examples of cyclic oligosaccharides include cyclodextrins such as α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin, and among them, α-cyclodextrin is preferable.
The cyclic molecules constituting the polyrotaxane compound (B) may be identical to or different from one another.

In the polyrotaxane compound (B), the cyclic molecule has a crosslinkable functional group. When the polyrotaxane compound (B) has a crosslinkable functional group in the cyclic molecule, it becomes possible to form a crosslinked body between the polyolefin (A) and the cyclic molecule of the polyrotaxane compound (B). Thereby, in the polyrotaxane compound which comprises the said crosslinked body, when a cyclic molecule moves freely along a linear molecule, the pulley effect is exhibited and the softness | flexibility as a crosslinked body improves remarkably.
As a result, the elastic modulus of the release layer formed by the release agent composition of the present invention is favorably reduced, and a release layer more excellent in release property can be formed. In addition, the residual adhesion rate can also be improved.
In addition, the crosslinkable functional group which the cyclic molecule which comprises a polyrotaxane compound (B) has means the functional group which has the reactivity with a crosslinking agent (C) as the above-mentioned definition.

The crosslinkable functional group possessed by the polyrotaxane compound (B) is selected in relation to the crosslinker (C).
As a crosslinkable functional group which a polyrotaxane compound (B) has, a hydroxyl group, an acryloyl group, a methacryloyl group, an amino group, a carboxy group etc. are mentioned, for example. Among these, the crosslinkable functional group is preferably a hydroxyl group from the viewpoint of making the reactivity with the crosslinking agent (C) better.

  When the cyclic molecule (cyclic oligosaccharide) of the polyrotaxane compound (B) has a hydroxyl group as a crosslinkable functional group, the hydroxyl group is a hydroxyl group that the cyclic oligosaccharide has in the original (the state before modification). It may be a hydroxyl group introduced as a substituent to a cyclic oligosaccharide.

In addition, from the viewpoint of making the solubility of the polyrotaxane compound (B) in the organic solvent good, part of the hydroxyl groups of the cyclic molecule (cyclic oligosaccharide) of the polyrotaxane compound (B) is modified by the hydrophobic molecular chain Is preferred.
As a hydrophobic molecular chain, polycaprolactone etc. are mentioned, for example.
Further, a functional group for introducing a hydrophobic molecular chain such as polycaprolactone into the cyclic molecule may be present between the hydroxyl group-derived group of the cyclic molecule and the hydrophobic molecular chain such as polycaprolactone. As such a functional group, a hydroxypropyl group etc. are mentioned, for example.

The linear molecule constituting the polyrotaxane compound (B) may be included in a cyclic molecule, and the cyclic molecule may freely move along the linear molecule without being fixed by a chemical bond such as a covalent bond. It is not particularly limited as long as it can be used.
Here, “linear” in the “linear molecule” of the polyrotaxane compound (B) means that it is substantially “linear”. That is, a linear molecule may have a branched chain as long as the cyclic molecule can move on the linear molecule.

  Examples of linear molecules of the polyrotaxane compound (B) include polyethylene glycol, polypropylene glycol, polyisoprene, polyisobutylene, polybutadiene, polytetrahydrofuran, polyacrylic acid ester, polydimethylsiloxane, polyethylene, polypropylene and the like. Among them, polyethylene glycol is preferred.

  The lower limit of the number average molecular weight of the linear molecule of the polyrotaxane compound (B) is preferably 3,000 or more, particularly preferably 10,000 or more, and further preferably 20,000 or more. preferable. When the lower limit value of the number average molecular weight is the above or more, the moving amount of the cyclic molecule on the linear molecule is secured, and the peeling force of the peeling layer can be easily made more excellent. In addition, the number average molecular weight of the linear molecule of the polyrotaxane compound is preferably 300,000 or less as an upper limit value, particularly preferably 200,000 or less, and further preferably 100,000 or less. . The solubility to the organic solvent of a polyrotaxane compound (B) and the compatibility with the components (A) and (C) in a release agent composition become favorable for the upper limit of a number average molecular weight to be the said or less.

The polyrotaxane compound (B) has blocking groups at both ends of the linear molecule. The block group is not particularly limited as long as the cyclic molecule can retain a form in which the cyclic molecule is in a skewered state by the linear molecule. Such groups include bulky groups, ionic groups and the like.
Specifically, for example, dinitrophenyl groups, cyclodextrins, adamantane groups, trityl groups, fluoresceins, pyrenes, anthracenes or the like, or a high number average molecular weight of 1,000 to 1,000,000. The main chain or side chain of the molecule may, for example, be mentioned, and among these, adamantane groups are preferred.
The blocking groups at both ends of the linear molecule may be identical to or different from one another.

  The mass average molecular weight of the polyrotaxane compound (B) is preferably 10,000 or more, more preferably 100,000 or more, and still more preferably 300,000 or more. Further, the mass average molecular weight is preferably 1,000,000 or less, more preferably 900,000 or less, and still more preferably 700,000 or less. When the mass average molecular weight of the polyrotaxane compound (B) is in the above-mentioned range, the compatibility with other components in the release agent composition is excellent. This makes it easy to add the polyrotaxane compound (B) in a sufficient amount to the release agent composition, and as a result, it is possible to effectively reduce the release force of the release layer.

  The polyrotaxane compound (B) described above can be obtained by a conventionally known method.

  In addition, a polyrotaxane compound (B) may be used individually by 1 type, and may be used combining 2 or more types.

<Crosslinking agent (C)>
A crosslinking agent (C) is selected according to the kind of crosslinkable functional group which a polyolefin (A) and a polyrotaxane compound (B) have, and if a crosslinking reaction is possible, it will not be specifically limited.
For example, when the crosslinkable functional groups possessed by the polyolefin (A) and the polyrotaxane compound (B) are both hydroxyl groups, as the crosslinking agent, a melamine compound, an isocyanate compound, an epoxy compound, an aziridine compound, a hydrazide compound, an oxazoline compound, a carbodiimide compound And one or more selected from the group consisting of urea compounds, dialdehyde compounds, and metal chelate compounds.
Among these, one or more selected from the group consisting of a melamine compound, an isocyanate compound, and an epoxy compound is more preferable, and a melamine compound is more preferable from the viewpoint of improving the solvent resistance.

As the melamine compound, from the group consisting of methylolated melamine resin, iminomethylolated melamine resin, methylated melamine resin, ethylated melamine resin, propylated melamine resin, butylated melamine resin, hexylated melamine resin, and octylated melamine resin It is preferable that it is 1 or more types chosen.
Among these, methylolated melamine resins, iminomethylolated melamine resins, and methylated melamine resins are more preferably one or more selected from the group consisting of methylated melamine resins, and methylated melamine resins are more preferable.

When a melamine compound is selected as the crosslinking agent (C), the release agent composition may further contain an acid catalyst. By using an acid catalyst, both the crosslinking reactivity between the polyolefin (A) and the melamine compound and the crosslinking reactivity between the polyrotaxane compound (B) and the melamine compound are improved, and the polyolefin (A) and the polyrotaxane compound (B) It is easy to form a cross-linked body with the cyclic molecule of the above, and it is easy to make the releasability further excellent.
The acid catalyst is not particularly limited, but, for example, organic acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, and alkyl phosphoric acid esters are preferable.
The above acid catalysts may be used alone or in combination of two or more.
The amount of the acid catalyst used is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, and still more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the polyolefin (A).

<Other additives>
The release agent composition of one embodiment of the present invention may optionally contain the components (A), (B), and (C) described above, and additives other than the acid catalyst.
Examples of such additives include various additives such as antioxidants, ultraviolet light absorbers, inorganic or organic fillers, antistatic agents, surfactants, photoinitiators, light stabilizers and the like.

<Silicone compound>
The release agent composition according to one aspect of the present invention is preferably a release agent composition substantially free of a silicone compound.
When a release sheet having a release layer formed from a release agent composition containing a silicone compound is used in an electronic material application, the silicone compound may be transferred to the electronic component to cause corrosion or malfunction of the electronic component. It is.
The content of the silicone compound in the release agent composition according to one aspect of the present invention is preferably less than 5.0% by mass, more preferably 2.0% by mass, based on the total amount (100% by mass) of the release agent composition. %, More preferably less than 1.0%, even more preferably less than 0.1%, even more preferably less than 0.01%.

<Dilution solvent>
In one aspect of the present invention, from the viewpoint of improving the coatability to a substrate, the release agent composition may be in the form of a solution by adding a dilution solvent to the various active ingredients described above.
The dilution solvent is selected from organic solvents in which the solubility of the components (A), (B) and (C) described above is good.
As such an organic solvent, toluene, xylene, heptane, octane, methanol, ethanol, isopropyl alcohol, isobutanol, n-butanol, ethyl acetate, acetone, methyl ethyl ketone, cyclohexanone, tetrahydrofuran etc. are mentioned, for example.
These may be used alone or in combination of two or more.
In addition, the organic solvent used as a dilution solvent may use the organic solvent used at the time of the synthesis | combination of the above-mentioned component (A), (B) and (C) as it is, and can apply | coat a release agent composition uniformly. Thus, the organic solvent used in the synthesis of the components (A), (B) and (C) described above and / or one or more other organic solvents may be added.

The amount of the dilution solvent may be appropriately selected so that the release agent composition has an appropriate viscosity at the time of application.
Specifically, the concentration of the active ingredient (solid content) contained in the solution of the release agent composition is preferably 0.1 to 15% by mass, more preferably 0.2 to 10% by mass, and still more preferably 0.5. It is prepared to be in the range of -5% by mass.

[Physical Properties of Peeling Layer]
<Peeling force>
When the release sheet is used for a pressure-sensitive adhesive body including a pressure-sensitive adhesive layer such as a pressure-sensitive adhesive sheet, the release force of the release layer formed from the release agent composition of one embodiment of the present invention to the pressure-sensitive adhesive layer is preferably 500 mN /. It is 20 mm or less, more preferably 400 mN / 20 mm or less, further preferably 300 mN / 20 mm or less, and still more preferably 200 mN / 20 mm or less. If the peeling force is 500 mN / 20 mm or less, desired peelability can be easily obtained in the peeling layer not using the silicone-based release agent composition. In addition, the peeling force with respect to the adhesive layer of a peeling layer is 30 mN / 20 mm or more normally.
Peeling force can be measured by the method described in the examples described later.
In addition, as an adhesive which comprises an adhesive layer, the polyester type adhesive is mentioned, for example.

<Remaining adhesion rate>
The residual adhesion rate of the release layer formed from the release agent composition of one embodiment of the present invention is preferably 62% or more, more preferably 65% or more, still more preferably 70% or more, still more preferably 75% or more is there. If the residual adhesion rate is 62% or more, it becomes difficult for the release agent component to migrate to the adherend. Therefore, when the adherend is a pressure-sensitive adhesive layer, it is possible to suppress a decrease in the adhesive strength of the pressure-sensitive adhesive layer due to the transfer of the release agent component. The upper limit of the residual adhesion rate is 100% and is usually less than 100%.
The residual adhesion rate can be measured by the method described in the examples below.

[Configuration of release sheet]
The release sheet of the present invention has a substrate and a release layer provided on the substrate.
The release layer is formed from the release agent composition of the present invention.
FIG. 1 is a schematic cross-sectional view showing the release sheet of one embodiment of the present invention. The release sheet 1 has a substrate 10 and a release layer 11 provided on the substrate 10. The release layer 11 is a crosslinked product formed of a release agent composition which contains a polyolefin (A) having a crosslinkable functional group as a main component and contains a polyrotaxane compound (B) and a crosslinking agent (C).
In addition, between the base material 10 and the peeling layer 11, other layers, such as an easily bonding layer and an antistatic layer (not shown), may be provided.
Hereinafter, the peeling layer and base material which comprise the peeling sheet of this invention are demonstrated.

<Peeling layer>
The release layer is a crosslinked body formed of a release agent composition containing a polyolefin (A) having a crosslinkable functional group as a main component and containing a polyrotaxane compound (B) and a crosslinking agent (C).
The release layer is not only a cross-linked product of polyolefins (A) having crosslinkable functional groups, a cross-linked product of polyrotaxane compounds (B) but also polyolefins (A) and polyrotaxane compounds (B) having crosslinkable functional groups. It contains a cross-linked body with the cyclic molecule to constitute. Thus, in the polyrotaxane compound constituting the crosslinked body by containing the crosslinked body of the polyolefin (A) having a crosslinkable functional group and the cyclic molecule constituting the polyrotaxane compound (B), the cyclic molecule is straight. By freely moving along the chain molecules, a pulley effect is exhibited, and as a result, it is possible to make a release layer excellent in release properties. Moreover, it can be set as the peeling layer excellent also in the residual adhesion rate.
The thickness of the release layer is not particularly limited, but is usually 25 to 1000 nm, preferably 50 to 500 nm. If the thickness of the release layer is 25 nm or more, it is easy to obtain desired light release properties. When the thickness of the release layer is 1000 nm or less, the curability of the coating film of the release agent composition can be improved.

<Base material>
As a substrate used for the release sheet of the present invention, for example, papers such as high quality paper, clay coated paper, cast coated paper, kraft paper, etc., laminated paper obtained by laminating thermoplastic resins such as polyethylene resin on these papers Paper material sheet such as synthetic paper, polyolefin resin such as polyethylene resin and polypropylene resin; polyester resin such as polybutylene terephthalate resin, polyethylene terephthalate resin, polyethylene naphthalate resin; polyetherimide resin; acetate resin; polystyrene resin; vinyl chloride resin Sheets of synthetic resins such as
The substrate may be a single layer or a multilayer of two or more layers of the same or different types.
The thickness of the substrate is not particularly limited, but it is usually 10 to 300 μm, preferably 20 to 200 μm. If the thickness of the base material is 10 to 300 μm, for example, it is possible to give stiffness and strength suitable for processing such as printing, cutting and sticking on a pressure-sensitive adhesive sheet and the like using a release sheet.

Moreover, when using a synthetic resin as a base material, in order to improve the adhesiveness of a base material and a peeling layer on the surface which provides the peeling layer of a base material, it is a surface by methods, such as an oxidation method and an uneven surface method, if desired. It can be processed.
Examples of the oxidation method include corona discharge surface treatment, chromic acid surface treatment (wet process), flame surface treatment, hot air surface treatment, ozone / ultraviolet irradiation surface treatment and the like. Moreover, as a roughening method, the sandblasting method, the solvent treatment method, etc. are mentioned, for example. Although these surface treatment methods are suitably selected according to the kind of base material, generally, a corona discharge surface treatment method is preferably used from an effect and a viewpoint of operativity. Also, primer treatment can be performed.

In the release sheet of the present invention, the surface on the release layer side may be embossed or the like to form asperities on the surface of the release sheet.
In the release sheet of the present invention, another layer such as an easy adhesion layer or an antistatic layer may be provided between the substrate and the release layer. By providing the easy-adhesion layer, the release sheet can effectively prevent the release layer from falling off from the release sheet.

The easy adhesion layer is usually formed by applying an easy adhesion coating agent on the surface on the release layer side of the substrate. Examples of easy adhesion coating agents include polyester resins, urethane resins, acrylic resins, melamine resins, oxazoline group-containing resins, carbodiimide group-containing resins, epoxy group-containing resins, isocyanate-containing resins, and copolymers of these, And coating agents mainly composed of natural rubber and synthetic rubber.
One of these resins may be used alone, or two different resins may be used in combination. In order to improve the coatability of the easy-adhesion coating on the substrate surface and the adhesion between the substrate and the easy-adhesion layer, the surface of the substrate to which the easy-adhesion coat is to be applied is chemically treated and discharge treated You may surface-treat, etc.

  The thickness of the easy adhesion layer is preferably 50 nm or more, and more preferably 100 nm or more. The thickness is preferably 5 μm or less, more preferably 1 μm or less. By the said thickness being 50 nm or more, the effect of an easily bonding layer can be acquired favorably. Moreover, when the said thickness is 5 micrometers or less, the slipperiness of the surface on the opposite side to the base material of an easily bonding layer becomes favorable, and the workability which apply | coats a release agent composition on an easily bonding layer is favorable. become.

[Use of release sheet]
The release sheet of the present invention can be used as a protective sheet for various pressure-sensitive adhesives such as a pressure-sensitive adhesive sheet, and for example, the pressure-sensitive adhesive layer side of a pressure-sensitive adhesive sheet comprising a substrate and a pressure-sensitive adhesive layer provided on one surface of the substrate It is used by sticking on the surface. Moreover, it can be used also as a process film at the time of producing various resin sheets, ceramic green sheets, synthetic leather, various composite materials and the like. When used as a process film, various sheet materials formed by casting, coating or the like a resin, ceramic slurry or the like on the surface of the release sheet on the release layer side are used in the step of releasing from the release sheet. The release sheet of the present invention is particularly preferably used for electronic devices because the release layer is formed of a non-silicone release agent composition. For example, in the process of manufacturing electronic components such as relays, various switches, connectors, motors, hard disks, etc., it can be suitably used as a release sheet for adhesive sheets such as temporary tacking at the time of assembly of electronic components and content display of components.

[Method of manufacturing release sheet]
The release sheet of the present invention is obtained, for example, by applying the release agent composition of the present invention on at least one surface of a substrate, heat treating it, and then forming polyolefin (A) and polyrotaxane compound (B) having a crosslinkable functional group. Can be crosslinked with a crosslinking agent (C) to form a crosslinked product as a release layer.
The release agent composition may be in the form of a solution diluted with a dilution solvent, as described above.

  100-170 degreeC is preferable and, as for heat processing temperature, 130-160 degreeC is more preferable. The heat treatment time is not particularly limited, but preferably 30 seconds to 5 minutes.

  As a method of applying the release agent composition, for example, a gravure coating method, a bar coating method, a spray coating method, a spin coating method, an air knife coating method, a roll coating method, a blade coating method, a gate roll coating method, a die coating method, etc. It can be mentioned.

  The application thickness of the release agent composition is adjusted such that the thickness of the obtained release layer falls within the above-mentioned range.

  The present invention will be specifically described by the following examples, but the present invention is not limited to the following examples.

  Physical property values in the following Examples and Comparative Examples are values measured by the following methods.

[Peeling layer thickness]
The thickness of the peeling layer was measured using a spectral ellipsometer (trade name: Spectroscopic Ellipsometry 2000U, manufactured by JA Woollam Japan Co., Ltd.).

  The release agent composition used in the following Examples 1 to 5 and Comparative Example 1 was prepared by the following method.

[Examples and Comparative Examples]
The release sheets of Examples 1 to 5 and Comparative Example 1 were produced in the following procedure.
In the following description, “parts by mass” is an active ingredient (solid content) converted value.

Example 1
As a polyolefin (A) having a crosslinkable functional group, a hydrogenated product of polyisoprene having hydroxyl groups only at both ends of the main chain (manufactured by Idemitsu Kosan Co., Ltd., trade name: Epol (registered trademark), solid content concentration: 100 mass %, Number average molecular weight: 2,500) were used. Hereinafter, this is referred to as "both terminal hydroxyl group modified hydrogenated polyisoprene".
As a polyrotaxane compound (B), a hydroxyl group-modified polyrotaxane (manufactured by Advanced Soft Materials, product name: Cerm (registered trademark) super polymer A 1000, solid content concentration: 100% by mass, mass average molecular weight: 600,000) was used .
As a crosslinking agent (C), methylated melamine resin (manufactured by Hitachi Chemical Polymer, product name: Tess Fine (registered trademark) 200, solid concentration 80% by mass, dilution solvent: isobutanol / toluene = 1/1) is used It was.
P-Toluenesulfonic acid was used as an acid catalyst.

5 parts by mass of hydroxyl group-modified polyrotaxane, 10 parts by mass of methylated melamine resin and 2.0 parts by mass of p-toluenesulfonic acid are added to 85 parts by mass of hydroxyl group-modified hydrogenated polyisoprene at both ends, and release agent composition I got a thing. In addition, "mass part" here means the mass part in conversion of solid content.
The hydroxyl-modified polyrotaxane was added as a solution in which the solid concentration was diluted to 10% by mass with toluene.
Moreover, p-toluenesulfonic acid was added as a solution diluted to a solid content concentration of 50 mass% using a mixed solvent of methanol and isopropyl alcohol (mass ratio 41.2: 9.4).
The obtained release agent composition is diluted to a solid content concentration of 2.5% by mass using a mixed solvent of toluene and methyl ethyl ketone (mass ratio 6: 4), and the form of a solution is a coating solution of the release agent composition. And

The coating solution of the obtained release agent composition is applied to one side of a 50 μm thick polyethylene terephthalate film (product name: Diafoil T-100, manufactured by Mitsubishi Chemical Corporation) using a meyer bar to form a coating film. did.
Then, the coating film was cured by drying at 150 ° C. for 1 minute to form a release layer having a thickness of 150 nm, to obtain a release sheet.

<Examples 2 to 5, Comparative Example 1>
A release sheet was produced in the same manner as in Example 1 except that the compounding ratio of the both terminal hydroxyl group-modified hydrogenated polyisoprene, the hydroxyl group-modified polyrotaxane, and the methylated melamine resin was changed as shown in Table 1.

  The following measurements and evaluations were performed on the release sheets of Examples 1 to 5 and Comparative Example 1.

[Measurement of peeling force]
On the release layer of the release sheets of Examples 1 to 5 and Comparative Example 1, a 20 mm wide polyester adhesive tape (manufactured by Nitto Denko Corporation, product number: No. 31B) is attached using a 5 kg roller to form an adhesive sheet. Made.
After 30 minutes of application, the obtained adhesive sheet is fixed to a universal tensile tester (manufactured by Shimadzu Corporation, trade name: Autograph AGS-20NX), and in accordance with JIS K6854: 1999, the tensile speed in the direction of 180 ° The peel strength (mN / 20 mm) of the release sheet was measured by peeling the release layer from the pressure-sensitive adhesive sheet at a speed of 0.3 m / min.

[Measurement of residual adhesion rate]
A polyester adhesive tape (manufactured by Nitto Denko Corporation, product number: No. 31B) is bonded onto the release layer of the release sheet of Examples 1 to 5 and Comparative Example 1, and a load of 20 g / cm ² is applied to obtain 70 ° C. Aging was performed for 24 hours.
Then, the polyester adhesive tape was peeled off from the release sheet, and the polyester adhesive tape was attached to a stainless steel plate. Then, the polyester pressure-sensitive adhesive tape was peeled from the stainless steel plate at a tensile speed of 0.3 m / min in the 180 ° direction, and the resistance (resistance A) at that time was measured.
On the other hand, a polyester adhesive tape (made by Nitto Denko Corporation, product number: No. 31B) not attached to a release sheet is attached to a stainless steel plate, and the resistance (resistance B) is measured in the same manner as above. did.
And the residual adhesion rate (%) was computed from the "resistance A" and the "resistance B" using the following formula | equation.
Residual adhesion rate (%) = (resistance A / resistance B) × 100

  The results are shown in Table 1.

From Table 1, the following can be seen.
The release sheet of Examples 1 to 5 having a release layer formed of a release agent composition containing a polyolefin (A) having a crosslinkable functional group as a main ingredient and containing a polyrotaxane compound (B) and a crosslinking agent (C) is It can be seen that the peelability and the residual adhesion rate are excellent.
On the other hand, it can be seen that the release sheet of Comparative Example 1 having a release layer formed from a release agent composition not containing a polyrotaxane compound has a high release force and a low residual adhesion rate.
Furthermore, the residual adhesion rate improves when the compounding ratio of the polyrotaxane compound (B) with respect to polyolefin (A) is raised from the evaluation result of the peeling force of the peeling sheet of Examples 1-5, but the compounding of polyrotaxane compound (B) It turns out that the improvement effect of a residual adhesion rate will be saturated if a ratio becomes more than fixed. On the other hand, it is understood that the peeling force decreases as the blending ratio of the polyrotaxane compound (B) to the polyolefin (A) is increased.

1 Peeling sheet 10 Base material 11 Peeling layer

Claims (5)

  The release agent composition which contains the polyolefin (A) which has a crosslinkable functional group as a main ingredient, and contains a polyrotaxane compound (B) and a crosslinking agent (C).   The release agent composition of Claim 1 whose crosslinkable functional group which polyolefin (A) has is a hydroxyl group.   The release agent composition according to claim 1 or 2, wherein the polyolefin skeleton of the polyolefin (A) is a hydrogenated product of polyolefin.   The release agent composition according to any one of claims 1 to 3, wherein the crosslinking agent (C) is a melamine compound.   A release sheet comprising a substrate and a release layer formed of the release agent composition according to any one of claims 1 to 4.