KR20210145132A - release sheet - Google Patents

Abstract

A release sheet having a release layer and a base material, wherein the release layer is a cured product of a release agent composition containing an acrylic resin (A), an amino resin (B), and a polyolefin (C) having a crosslinkable functional group, the component Content of (B) is 15 mass % or more and 65 mass % or less among 100 mass % of total content of component (A), component (B), and component (C), and content of the said component (C) is component ( It is related with the release sheet which is 55 mass % or less in 100 mass % of total content of A), a component (B), and a component (C).

Description

release sheet

The present invention relates to a release sheet.

In general, a release sheet has, for example, a base material such as paper, plastic film or polyethylene laminate paper, and a release layer formed on the base material. The release layer is formed, for example, by applying and curing a release agent composition containing a reactive compound on a substrate.

The release sheet is widely used, for example, as a protective sheet for a pressure-sensitive adhesive layer of an adhesive sheet or the like, a process film for resin sheet production, a process film for ceramic green sheet film formation, a process film for synthetic leather production, and the like.

As a release agent composition for forming a release layer, the silicone type release agent composition containing silicone compounds, such as a silicone resin, siloxane, or silicone oil, is widely used.

However, a silicone compound may migrate to the contact surface with a peeling layer, for example, the adhesive layer surface of an adhesive sheet. In addition, after transition, it may vaporize gradually.

Therefore, when a release sheet having a release layer formed of a silicone release agent composition is used for, for example, an electronic material application, the silicone compound migrates to the electronic component, which may cause corrosion or malfunction of the electronic component.

Then, examination which forms a peeling layer is performed, without using a silicone type 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.

(Patent Document 1) Japanese Patent Application Laid-Open No. 2011-52207

In general, the preferable value of the peeling force of the release sheet varies depending on the application to be applied or the type of the object to be laminated. For example, in order to facilitate the peeling operation at the time of peeling, a lower peeling force is desired. Therefore, when the retention (falling resistance) of the object to be laminated is given priority, a higher peeling force is preferable, so that the peeling force is not extremely low and a release sheet having an appropriate peeling force is also required. Thus, it is calculated|required to design the release agent which can make the product manufactured using a release sheet suitable for the peeling force suitable for the use form.

Moreover, there exists a possibility that a peeling sheet may curl depending on the storage condition of a peeling sheet, for example, during storage under a high temperature condition, or long-term storage. Moreover, there exists a possibility that the said release sheets may raise|generate blocking, when overlapping and storing a release sheet, or winding up and storing in roll shape. Therefore, in addition to favorable peelability, characteristics such as curl resistance and blocking resistance are also calculated|required by a peeling sheet. Moreover, depending on the use for which the release sheet is used, for example, in an electronic material use etc., the tolerance with respect to an organic solvent (solvent resistance) is calculated|required of a release sheet in many cases.

Then, an object of this invention is to provide the peeling sheet which has a peeling layer favorable in peelability, curl resistance, blocking resistance, and solvent resistance.

The present inventors have found that a release sheet having a release layer which is a cured product of a release agent composition containing components (A) to (C) described later and containing components (B) and (C) in specific amounts can solve the above problems found out that there is

That is, the present invention relates to the following [1] to [7].

[1] A release sheet having a release layer and a base material, comprising:

The release layer is a cured product of a release agent composition containing an acrylic resin (A), an amino resin (B), and a polyolefin (C) having a crosslinkable functional group;

Content of the said component (B) is 15 mass % or more and 65 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C),

The release sheet whose content of the said component (C) is 55 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C).

[2] The release sheet according to [1], wherein the component (A) has a glass transition temperature (Tg) of 10°C or higher.

[3] The release sheet according to [1] or [2], wherein the component (B) is a melamine resin.

[4] The release sheet according to any one of [1] to [3], wherein the crosslinkable functional group of the component (C) is a hydroxyl group.

[5] The release sheet according to any one of [1] to [4], wherein the component (C) is polybutadiene having a crosslinkable functional group or polyisoprene having a crosslinkable functional group.

[6] The release sheet according to any one of [1] to [5], wherein the component (C) is a hydrogenated polyolefin having a crosslinkable functional group.

[7] The release sheet according to any one of [1] to [6], wherein the peeling force at the time of peeling from the pressure-sensitive adhesive layer is 500 to 4,000 mN/20 mm.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the peeling sheet which has a peeling layer favorable in peelability, curl resistance, blocking resistance, and solvent resistance.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing of the release sheet of one aspect|mode of this invention.

In this specification, "solid content" refers to the component except a solvent among the components contained in a release agent composition.

In addition, in this specification, the holdability of the object from the object which laminated|stacked the release sheet until the peeling operation of the said release sheet is performed is also called "fall-off resistance."

In addition, in this specification, with respect to a preferable numerical range (for example, a range, such as content), the lower limit and upper limit described in stages can be combined independently, respectively. For example, "preferably 10 or more, more preferably 30 or more, still more preferably 40 or more, and preferably 90 or less, more preferably 80 or less, still more preferably 70 or less" From the description, as a suitable range, a range combining an independently selected lower limit and an upper limit such as "10 or more and 70 or less", "30 or more and 70 or less", and "40 or more and 80 or less" can also be selected. Moreover, from the same description, for example, it is also possible to simply select a range in which either a lower limit value or an upper limit value such as "40 or more" or "70 or less" is defined. Further, for example, "preferably 10 or more and 90 or less, more preferably 30 or more and 80 or less, still more preferably 40 or more and 70 or less", "preferably 10-90, more preferably 30-80" , more preferably from 40 to 70”. In addition, in this specification, description of a numerical range WHEREIN: For example, description of "10-90" has the same meaning as "10 or more and 90 or less."

[Peel Sheet]

The release sheet of this invention has a release layer and a base material.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows the release sheet of one aspect|mode of this invention. The release sheet 1 has a base material 10 and a release layer 11 formed on the base material 10 . The release layer 11 is a hardened|cured material of the release agent composition containing an acrylic resin (A), an amino resin (B) of a specific amount, and polyolefin (C) which has a crosslinkable functional group of a specific amount.

Moreover, in one aspect of this invention, the peeling sheet may have a peeling layer on both surfaces of the base material 10 (not shown). In this case, as long as the effect of the present invention is not impaired, at least one of the plurality of release layers may be the release layer 11 , and when a plurality of release layers 11 are present, each release layer 11 is formed The composition of the releasing agent composition to be made may be mutually the same or different.

In addition, each of the above-mentioned aspects may be an aspect consisting of only the base material 10 and the release layer 11, and between the base material 10 and the release layer 11, an easy-to-adhesive layer, an antistatic layer, etc. (not shown) A layer may be formed.

Hereinafter, the release layer and base material which comprise the release sheet of this invention are demonstrated.

<Releasable layer>

The release layer of the release sheet of the present invention is a release agent composition containing an acrylic resin (A), an amino resin (B), and a polyolefin (C) having a crosslinkable functional group, wherein the content of the component (B) is In 100 mass % of total content of a component (A), a component (B), and a component (C), they are 15 mass % or more and 65 mass % or less, and content of the said component (C) is a component (A), a component (B) And it is hardened|cured material which can be formed from the release agent composition which is 55 mass % or less in 100 mass % of total content of a component (C).

Hereinafter, the release agent composition which is a forming material of a release layer is demonstrated.

In addition, the following description WHEREIN: "Content of each component in the release agent composition" can also be regarded as "content of each component in the release layer formed from the said release agent composition". Moreover, the said content can also be considered as the value computed from the compounding quantity at the time of mix|blending each component.

In addition, in this specification, content and total content of each component, and the value concerning the ratio of each component all point out the value of solid content conversion.

(Releasant composition)

The release agent composition includes an acrylic resin (A) (hereinafter also referred to as “component (A)”), an amino resin (B) (hereinafter also referred to as “component (B)”.), and a polyolefin having a crosslinkable functional group. (C) (hereinafter also referred to as "component (C)") is contained, and content of the said component (B) is 100 mass % of total content of a component (A), a component (B), and a component (C) , 15 mass % or more and 65 mass % or less, and content of the said component (C) is 55 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C).

The present inventors examined variously in order to find out the prescription which can solve the said subject about prescription of the peeling layer using release agent compositions other than a silicone type release agent composition. As a result, it discovered that the prescription of the peeling layer using the peeling agent composition which satisfy|fills the above-mentioned requirements is an effective prescription, and led to this invention.

Hereinafter, each component contained in a release agent composition is demonstrated.

[Component (A): Acrylic resin]

The said releasing agent composition contains an acrylic resin as a component (A). Although the reason is not certain, when the said release agent composition contains component (A), it becomes possible to form the peeling layer which has the peeling force of the range which was difficult to obtain only with the combination of the components (B) and (C) mentioned later. .

The acrylic resin is, for example, a polymer containing a structural unit derived from an alkyl (meth)acrylate having a linear or branched alkyl group, or a structural unit derived from (meth)acrylate having a cyclic structure. and polymers containing

In this specification, "(meth)acrylate" is used as a term which means one or both of "acrylate" or "methacrylate". Similarly, "(meth)acryl" is used as a term meaning one or both of "acryl" or "methacryl".

As said acrylic resin, the polymer which has a structural unit (a1) derived from alkyl (meth)acrylate (a1') (hereinafter also referred to as "monomer (a1')") is preferable, and structural unit (a1) In addition, a copolymer having a structural unit (a2) derived from the functional group-containing monomer (a2') (hereinafter also referred to as “monomer (a2')”) is more preferable.

As carbon number of the alkyl group which a monomer (a1') has, Preferably it is 1-3.

In addition, a linear alkyl group may be sufficient as the alkyl group which a monomer (a1') has, and a branched chain alkyl group may be sufficient as it.

As a monomer (a1'), methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, etc. are mentioned, for example.

These monomers (a1') may be used independently and may be used in combination of 2 or more type.

As for the functional group which a monomer (a2') has, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, etc. are mentioned, for example. That is, as a monomer (a2'), a hydroxyl group containing monomer, a carboxyl group containing monomer, an amino group containing monomer, an epoxy group containing monomer, etc. are mentioned, for example.

When using these monomers (a2'), you may use independently and may use them in combination of 2 or more type.

As a monomer (a2'), a hydroxyl-containing monomer and a carboxyl group-containing monomer are preferable, and a hydroxyl-containing monomer is more preferable.

As a hydroxyl-containing monomer, hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acryl Hydroxyalkyl (meth)acrylates, such as a rate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Unsaturated alcohols, such as vinyl alcohol and allyl alcohol, etc. are mentioned.

As a carboxyl group containing monomer, For example, ethylenically unsaturated monocarboxylic acids, such as (meth)acrylic acid and a crotonic acid; Ethylenically unsaturated dicarboxylic acids, such as fumaric acid, itaconic acid, a maleic acid, and a citraconic acid, and its anhydride; 2-(acryloyloxy)ethyl succinate, 2-carboxyethyl (meth)acrylate, etc. are mentioned.

Examples of the amino group-containing monomer include aminoethyl (meth)acrylate, ethylaminoethyl (meth)acrylate, aminopropyl (meth)acrylate, ethylaminopropyl (meth)acrylate, n-butylaminoethyl ( meth)acrylate and the like.

As an epoxy group containing monomer, glycidyl (meth)acrylate etc. are mentioned, for example.

Moreover, the copolymer which has the structural unit (a3) derived from the monomer (a3') other than a monomer (a1') and (a2') may be sufficient as the said acrylic resin further.

As a monomer (a3'), For example, halogenated olefins, such as vinyl chloride and vinylidene chloride; Cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dicyclopentanyl (meth) acrylate (meth)acrylates having a cyclic structure such as , dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and imide (meth)acrylate; Styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, (meth)acrylamide, (meth)acrylonitrile, (meth)acryloylmorpholine, N-vinylpyrrolidone, etc. can be heard

When using these monomers (a3'), you may use independently and may use them in combination of 2 or more type.

In addition, in the said acrylic resin, each content of the structural units (a1), (a2) and (a3) in all the structural units (100 mass %) of an acrylic resin is, for example, a monomer (a1'), It can be adjusted by adjusting each compounding quantity of (a2') and (a3'). For example, each compounding quantity of monomers (a1'), (a2') and (a3') is adjusted suitably so that the suitable range of the glass transition temperature (Tg) mentioned later and/or the suitable range of a hydroxyl value may be satisfied. It is preferable to do

The glass transition temperature (Tg) of the component (A) is preferably 10°C or higher, more preferably 15°C or higher, still more preferably 20°C or higher from the viewpoint of improving the blocking resistance of the release sheet obtained. The upper limit of the glass transition temperature (Tg) is not particularly limited as long as the effect of the present invention is not impaired. For example, it is preferably 150°C. The said glass transition temperature (Tg) is measured by the method as described in the Example mentioned later, for example.

For example, when it is desired to obtain an acrylic resin having a desired glass transition temperature (Tg), the glass transition temperature (Tg) of the homopolymer obtained when polymerization alone is higher than the desired glass transition temperature (Tg) A monomer and a monomer having a glass transition temperature (Tg) of a homopolymer obtained when polymerization alone is lower than a desired glass transition temperature (Tg) is selected. Then, referring to the glass transition temperature (Tg) of the homopolymer obtained when each monomer is independently polymerized so that the obtained copolymer has a desired glass transition temperature (Tg), by appropriately adjusting the compounding amount of each monomer, the desired An acrylic resin having a glass transition temperature (Tg) can be obtained.

Moreover, the hydroxyl value of component (A) becomes like this from a viewpoint of improving the solvent resistance of the release sheet obtained, Preferably it is 5 mgKOH/g or more, More preferably, it is 8 mgKOH/g or more, More preferably, it is 10 mgKOH. more than /g. The upper limit of the hydroxyl value is not particularly limited as long as the effect of the present invention is not impaired. For example, preferably 200 mgKOH/g, more preferably 150 mgKOH/g, still more preferably 100 mgKOH/g. The value of the said hydroxyl value can be measured also by the method of JISK0070-1992, for example.

Moreover, when trying to obtain the acrylic resin which has a desired hydroxyl value, the acrylic resin which has a desired hydroxyl value can be obtained by adjusting suitably the compounding quantity of the hydroxyl-containing monomer mentioned above, for example.

Moreover, the mass average molecular weight (Mw) of a component (A) becomes like this. Preferably it is 5,000-100,000, More preferably, it is 8,000-80,000, More preferably, it is 10,000-50,000. The said mass average molecular weight (Mw) means the value of polystyrene conversion measured by gel permeation chromatography (GPC).

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

In one aspect of the present invention, from the viewpoint of improving the releasability of the release layer, the content of the component (A) is preferably in 100% by mass of the total content of the component (A), the component (B) and the component (C). Preferably it is 15 mass % or more, More preferably, it is 20 mass % or more, More preferably, it is 25 mass % or more. Moreover, from a viewpoint of solubility with respect to the dilution solvent at the time of coating film formation, and from a viewpoint of expressing the peeling force excellent in the balance of easy peelability and peeling-off resistance of a peeling layer, content of component (A) is component (A), In 100 mass % of total content of a component (B) and a component (C), Preferably it is 80 mass % or less, More preferably, it is 75 mass % or less, More preferably, it is 65 mass % or less.

[Component (B): amino resin]

The said releasing agent composition contains an amino resin in 15 mass % or more and 65 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C) as a component (B).

In the present specification, the term "amino resin" refers to a generic term for compounds obtained by reacting a compound having an amino group, such as melamine, urea, aniline, and guanamine, with an aldehyde such as formaldehyde and acetaldehyde. .

As an amino resin, it is a melamine resin; Urea resin (same as urea resin.) ; aniline resin; guanamine resin; and the like. In this, a melamine resin is preferable from a viewpoint of sclerosis|hardenability of a release agent composition, and the solvent resistance improvement of the release layer obtained.

The melamine resin is preferably a methylolated melamine resin, an iminomethylolated melamine resin, a methylated melamine resin, an ethylated melamine resin, a propylated melamine resin, a butylated melamine resin, a hexylated melamine resin, and an octylated melamine resin. At least one member selected from the group, more preferably at least one member selected from the group consisting of a methylolation melamine resin, an iminomethylolation melamine resin, and a methylation melamine resin. Among these, from a viewpoint of low-temperature curability of a peelable composition, More preferably, it is a methylated melamine resin.

A component (B) may be used individually by 1 type, and may be used in combination of 2 or more type.

In the release agent composition, when the content of the component (B) is more than 65 mass% in 100 mass% of the total content of the component (A), the component (B), and the component (C), due to the condensation reaction of the amino resin , the curl resistance of the obtained release sheet deteriorates. On the other hand, when content of component (B) is less than 15 mass % among 100 mass % of total content of a component (A), a component (B), and a component (C), it originates in the condensation reaction of an amino resin, and the release sheet obtained solvent resistance deteriorates.

Therefore, from a viewpoint of making favorable curl resistance and favorable solvent resistance compatible, content of a component (B) is 100 mass % of total content of a component (A), a component (B), and a component (C), Preferably 16 mass % or more, more preferably 18 mass% or more, still more preferably 20 mass% or more, and preferably 60 mass% or less, more preferably 55 mass% or less, still more preferably 45 mass% or less. .

[Component (C): Polyolefin (C) having a crosslinkable functional group]

The said releasing agent composition contains the polyolefin which has a crosslinkable functional group as a component (C) in 55 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C).

In this specification, "polyolefin" is used in the meaning including the polymer which polymerizes diolefin, such as butadiene and isoprene, as a monomer unit.

In addition, in this specification, a "crosslinkable functional group" means a functional group which reacts with the component (B) used as a crosslinking agent at least.

As said polyolefin, For example, polyethylene; polypropylene; copolymers such as ethylene-α-olefin copolymers obtained by polymerizing at least two olefins selected from the group consisting of ethylene, propylene, and α-olefins having 4 to 20 carbon atoms; polybutadiene; polyisoprene; Various polyolefins, such as these, are mentioned. Among these, from a viewpoint of obtaining a peeling layer provided with favorable peelability, polybutadiene or polyisoprene is preferable.

Moreover, although it changes with the value calculated|required as the use of a peeling sheet or the peeling force with the object laminated|stacked on the peeling layer, for example, the peeling force of the peeling layer obtained by the combination of components (A)-(C) When a peeling force higher within this range is calculated|required, polybutadiene is more preferable, and when a lower peeling force is calculated|required, polyisoprene is preferable.

As a crosslinkable functional group which component (C) 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, it is preferable that a crosslinkable functional group is a hydroxyl group from a viewpoint of making reactivity with a component (B) more favorable.

Moreover, although a component (C) should just have at least one crosslinkable functional group, it is preferable to have two or more crosslinkable functional groups. When a component (C) has two or more crosslinkable functional groups, although these functional groups may mutually be same or different, it is preferable that they are mutually identical.

The position of the crosslinkable functional group which the component (C) has is not particularly limited as long as it is a position where the crosslinkable functional group can react with the component (B).

Here, in one aspect of the present invention, it is preferable to have a crosslinkable functional group at at least one terminal of the molecular chain constituting the polymer backbone of the component (C), and the distance between the crosslinking points is increased to improve releasability. From the viewpoint of forming the release layer, it is more preferable to have crosslinkable functional groups at both ends of the molecular chain constituting the polymer backbone of the component (C), and only at both ends of the main chain constituting the polymer backbone of the component (C). It is more preferable to have a crosslinkable functional group.

Moreover, it is preferable that a component (C) is a hydrogenated polyolefin from a viewpoint of the temporal stability of peeling force. Although the degree of hydrogenation of component (C) may be partial hydrogenation or complete hydrogenation may be sufficient, from a viewpoint of improving the chemical stability of the peeling force of a peeling layer, partial hydrogen with low residual rate of unsaturated bonds, such as a vinyl group. It is preferable that it is an additive, and it is more preferable that it is a complete hydrogenated substance.

Therefore, from the same viewpoint, the component (C) preferably has a low bromine number. The lower the bromine number, the lower the residual ratio of unsaturated bonds including unsaturated bonds in the component (C), and since it is difficult to change chemically such as oxidation, the stability over time of the peeling force of the peeling layer tends to be good.

For example, in one aspect of the present invention, the bromine number of component (C) is preferably 100 g/100 g or less, more preferably 20 g/100 g or less, still more preferably 10 g/100 g or less. Hereinafter, more preferably, it is 8 g/100 g or less.

The value of the said bromine number is a value measured based on JISK2605-1996.

The number average molecular weight (Mn) of component (C) becomes like this. Preferably it is 1,000-30,000, More preferably, it is 1,000-20,000, More preferably, it is 1,000-10,000, More preferably, it is 1,000-5,000.

In this specification, the said number average molecular weight (Mn) is a standard polystyrene conversion value measured by the gel permeation chromatography (GPC) method, For example, it is measured by the method as described in the Example mentioned later.

A component (C) may be used individually by 1 type, and may be used in combination of 2 or more type.

When the release agent composition contains more than 55 mass% of the component (C) in 100 mass% of the total content of the component (A), the component (B), and the component (C), the blocking resistance of the obtained release sheet deteriorates, throw away Therefore, from a viewpoint of improving blocking resistance, content of component (C) is 100 mass % of total content of component (A), component (B), and component (C), Preferably it is 45 mass % or less, more Preferably it is 35 mass % or less, More preferably, it is 25 mass % or less. Moreover, content of component (C) is 100 mass % of total content of a component (A), a component (B), and a component (C) from a viewpoint of obtaining favorable peelability as a peeling layer, Preferably it is 5 mass % or more. , More preferably, it is 10 mass % or more, More preferably, it is 15 mass % or more.

In one aspect of the present invention, the total content of the component (A), the component (B), and the component (C) in the release agent composition is based on the total amount of the release agent composition (solid content 100% by mass), Preferably It is 70 mass % or more, More preferably, it is 80 mass % or more, More preferably, it is 90 mass % or more, More preferably, it is 95 mass % or more.

Moreover, in one aspect of this invention, in the range which does not impair the effect of this invention, from a viewpoint of obtaining favorable peeling force, the content ratio (A/B) of a component (A) and a component (B) is a mass ratio , preferably 15/85 to 85/15. And, for example, when using polybutadiene as a polyolefin of a component (C), from a viewpoint of making this application effect more easily acquired, More preferably, it is 40/60 - 80/20, More preferably, 55/45 - 80/20, more preferably 65/35 to 78/22.

Moreover, in one aspect of this invention, the content ratio (A/C) of a component (A) and a component (C) is mass ratio, Preferably it is 36/64-96/4, More preferably, it is 37/ 63 to 95/5. And, for example, when polybutadiene is used as the polyolefin of component (C), from a viewpoint of making this application effect more easily acquired, More preferably, it is 40/60 - 95/5, More preferably, 60/40 to 95/5, more preferably 70/30 to 80/20.

[acid catalyst]

1 aspect of this invention WHEREIN: The said releasing agent composition may contain the acid catalyst further. By using an acid catalyst, the crosslinking reaction of component (A) and component (B) and/or the crosslinking reaction of component (A) and component (C), and the crosslinking reactivity of component (B) and component (C) are improved, , it can be made easy to improve the temporal stability of the peeling force of a peeling layer more.

Although there is no restriction|limiting in particular as an acid catalyst, For example, organic acid catalysts, such as p-toluenesulfonic acid, methanesulfonic acid, and an alkyl phosphate ester, are preferable.

The said acid catalyst may be used independently and may be used in combination of 2 or more type.

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, still more preferably 1 to 100 parts by mass of the total amount of components (A), (B) and (C). - 5 parts by mass.

[Other additives]

One aspect of the present invention WHEREIN: The said releasing agent composition is the range which does not impair the effect of this invention, and as needed, components (A), (B) and (C) mentioned above, and those other than an acid catalyst as needed. You may contain an external additive.

As such an additive, various additives, such as antioxidant, a ultraviolet absorber, an inorganic or organic filler, an antistatic agent, surfactant, a photoinitiator, and a light stabilizer, are mentioned, for example.

[Silicone compound]

In one aspect of the present invention, the release agent composition preferably does not contain a silicone compound substantially.

When a release sheet having a release layer formed of a release agent composition containing a silicone compound is used, for example, the silicone compound may migrate into the affixed pressure-sensitive adhesive layer, thereby impairing the original performance of the pressure-sensitive adhesive layer. Alternatively, the silicone compound may migrate from the release layer directly or through the pressure-sensitive adhesive layer to a substance in contact with the release sheet (for example, a manufacturing device) or an object to be adhered of the pressure-sensitive adhesive layer, thereby causing corrosion or malfunction of the object. Because there are cases where

From such a viewpoint, in one aspect of the present invention, the content of the silicone compound in the release agent composition is preferably less than 5.0 mass%, more preferably 2.0, based on the total amount of the release agent composition (solid content: 100 mass%). It is less than mass %, More preferably, it is less than 1.0 mass %, More preferably, it is less than 0.1 mass %, More preferably, it is less than 0.01 mass %.

[isocyanate compound]

In one aspect of this invention, it is preferable that the said release agent composition does not contain an isocyanate compound substantially from a solvent resistance viewpoint.

In one aspect of the present invention, the content of the isocyanate compound in the release agent composition is preferably less than 1.0 mass%, more preferably less than 0.1 mass%, more preferably less than 1.0 mass%, based on the total amount (solid content: 100 mass%) of the release agent composition. Preferably it is less than 0.01 mass %, More preferably, it is less than 0.001 mass %.

[dilution solvent]

One aspect of this invention WHEREIN: From a viewpoint of improving the applicability|paintability with respect to a base material, a release agent composition adds a dilution solvent to each component mentioned above, and it is good also as a form of a solution.

The dilution solvent is selected from organic solvents with good solubility of the components (A), (B) and (C) described above.

As such an organic solvent, for example, toluene, xylene, heptane, octane, methanol, ethanol, isopropyl alcohol, isobutanol, n-butanol, ethyl acetate, acetone, methyl ethyl ketone, cyclohexanone, tetrahydro Furan etc. are mentioned.

These may be used independently and may be used in combination of 2 or more type.

In addition, as for the organic solvent used as a dilution solvent, the organic solvent used at the time of the synthesis|combination of the above-mentioned components (A), (B) and (C) may be used as it is, and in order to apply|coat the release agent composition uniformly, You may add the organic solvent used at the time of the synthesis|combination of one component (A), (B) and (C) and/or 1 or more types of organic solvents other than that.

What is necessary is just to select the quantity of a dilution solvent suitably so that it may become the quantity which has an appropriate viscosity at the time of application|coating of a release agent composition.

The solid content concentration specifically, contained in the solution of a release agent composition becomes like this. Preferably it is 0.1-15 mass %, More preferably, it is 0.2-10 mass %, More preferably, it adjusts so that it may become the range of 0.5-5 mass %.

Although there is no restriction|limiting in particular as for the thickness of a peeling layer, Preferably it is 25-1,000 nm, More preferably, it is 50-500 nm. When the thickness of the peeling layer is 25 nm or more, it is possible to suppress variation in peeling force due to non-uniformity of the application amount. Moreover, sclerosis|hardenability of the coating film of a release agent composition can be made favorable that the thickness of a release layer is 1,000 nm or less.

The thickness of the release layer is measured, for example, by the method described in Examples described later.

<mentioned>

Examples of the base material used for the release sheet of the present invention include papers such as fine paper, clay coated paper, cast coated paper, kraft paper, laminated paper obtained by laminating these papers with a thermoplastic resin such as polyethylene resin, synthetic paper, etc. polyolefin resins, such as a paper material sheet, a polyethylene resin, and a polypropylene resin; polyester resins such as polybutylene terephthalate resin, polyethylene terephthalate resin, and polyethylene naphthalate resin; polyetherimide resin; acetate resin; polystyrene resin; The sheet|seat of synthetic resins, such as a vinyl chloride resin, etc. are mentioned.

A single layer may be sufficient as a base material, and the multilayer of 2 or more layers of the same type or different type may be sufficient as it.

Although there is no restriction|limiting in particular as for the thickness of a base material, Preferably it is 10-300 micrometers, More preferably, it is 20-200 micrometers. When the thickness of the base material is 10 to 300 µm, for example, an adhesive sheet using a release sheet or the like can be given elasticity or strength suitable for processing such as printing, cutting and pasting.

In addition, when a synthetic resin is used as the base material, the surface on which the release layer of the base material is to be formed may be subjected to surface treatment by an oxidation method or a concave-convex method, if desired, in order to improve the adhesion between the base material and the release layer. have.

As the oxidation method, corona discharge surface treatment, chromic acid surface treatment (wet), flame surface treatment, hot air surface treatment, ozone/ultraviolet irradiation surface treatment, etc. are mentioned, for example. Moreover, as the unevenness|corrugation 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, in general, the corona discharge surface treatment method is preferably used from a viewpoint of an effect and operability. Moreover, a primer process can also be implemented.

The release sheet of the present invention may emboss or the like on the surface on the release layer side to form irregularities on the surface of the release sheet.

Moreover, in the release sheet of this invention, other layers, such as an easily bonding layer and an antistatic layer, may be formed between a base material and a peeling layer. When a peeling sheet is equipped with an easily bonding layer, drop-off|omission of the peeling layer from a peeling sheet can be prevented effectively.

An easily bonding layer is normally formed by apply|coating an easily bonding coating agent on the surface by the side of the peeling layer in a base material. Examples of the easy-to-adhesive coating agent include polyester-based resins, urethane-based resins, acrylic resins, melamine-based resins, oxazoline group-containing resins, carbodiimide group-containing resins, epoxy group-containing resins, isocyanate-containing resins, and copolymers thereof. and a coating agent containing natural rubber or synthetic rubber as a main component, and the like.

These resins may be used individually by 1 type, and may be used in combination of 2 different types. In addition, in order to improve the applicability of the easily-adhesive coating agent to the surface of the substrate, and the adhesion between the substrate and the easily-adhesive layer, the surface to which the easily-adhesive coating agent is applied in the substrate is subjected to chemical treatment, discharge treatment, etc. You may process.

The thickness of an easily bonding layer becomes like this. Preferably they are 50 nm - 5 micrometers, More preferably, they are 100 nm - 1 micrometer. When the said thickness is 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 slidability of the surface on the opposite side to the base material of an easily bonding layer becomes a favorable thing, and the workability|operativity which apply|coats a release agent composition on an easily bonding layer becomes favorable.

In general, the preferable value of the peeling force of the peeling sheet varies depending on the application to be applied or the type of the object to be laminated, and there are cases where a lower peeling force is desired so that the peeling operation at the time of peeling becomes smooth, or to improve the peeling resistance. In some cases, a higher peel force is desirable for this.

In one aspect of the present invention, the peeling force of the release layer exhibited by the release sheet is preferably 500 to 4,000 mN/20 mm, more preferably 1,000 to 3,950 mN/20 mm, and still more preferably 2,500 to 3,900 mN. /20 mm or more.

The value of the said peeling force is a value measured by the method as described in the Example mentioned later.

[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 pressure-sensitive adhesive sheets, for example, by sticking to the pressure-sensitive adhesive layer side surface of the pressure-sensitive adhesive sheet comprising a base material and a pressure-sensitive adhesive layer formed on one surface of the base material. used Moreover, it can be used as a process film at the time of producing various resin sheets, a ceramic green sheet, synthetic leather, various composite materials, etc. When using as a process film, it uses in the process of peeling from a peeling sheet various sheet materials formed by casting|flow_spreading, apply|coating resin, a ceramic slurry, etc. to the surface on the side of the peeling layer of a peeling sheet. Moreover, since the release layer of the release sheet of this invention is formed with the non-silicone type release agent composition, it can be used suitably also for electronic devices. For example, in the manufacturing process of electronic components such as relays, various switches, connectors, motors, and hard disks, it is preferably used as a release sheet for adhesive sheets such as temporary fixing at the time of assembly of electronic components or display of contents of components. can

[Method for producing release sheet]

The release sheet of this invention apply|coats the said release agent composition on at least one surface of a base material, heat-processes, for example, make components (A)-(C) react, and form hardened|cured material as a release layer. can be manufactured.

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. Moreover, although there is no restriction|limiting in particular for heat processing time, 30 second - 5 minutes are preferable.

As a coating method of 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. can be heard

The application thickness of the release agent composition is preferably adjusted so that the thickness of the release layer obtained is in the range described above.

Example

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

The physical property values in the following examples and comparative examples are values measured by the following method.

[Thickness of release layer]

The thickness of the release layer was measured using a spectroscopic ellipsometer (manufactured by J.A.Ulam Japan Co., Ltd., trade name "Spectral Ellipsometry 2000U").

[Glass Transition Temperature (Tg)]

The glass transition temperature (Tg) of the acrylic resin was measured using a differential scanning calorimetry apparatus (manufactured by TA Instruments Japan Co., Ltd., product name “DSC Q2000”) from 30° C. to 200° C., temperature increase rate 10° C./min. It was measured by raising the temperature to .

[Bromgar]

The value measured based on JISK2605-1996 was used.

[Mass Average Molecular Weight (Mw), Number Average Molecular Weight (Mn)]

The mass average molecular weight (Mw) of the acrylic resin and the number average molecular weight (Mn) of the polyolefin having a crosslinkable functional group were measured using a gel permeation chromatograph (GPC) apparatus (manufactured by Tosoh Corporation, product name “HLC-8320”), below, It measured under the conditions of and used the value converted into the number average molecular weight of standard polystyrene.

(Measuring conditions)

- Measurement sample: tetrahydrofuran solution with a sample concentration of 1% by mass

·Column: 2 pieces of 「TSK gel Super HM-H」, 1 piece of 「TSK gel Super H2000」 (all manufactured by Tosoh Corporation), connected in this order from the upstream

·Column temperature: 40 ℃

·Developing solvent: tetrahydrofuran

Flow rate: 0.60 ml/min

Detector: Differential refractometer (RI detector)

[Examples and Comparative Examples]

The release sheets of Examples 1-9 and Comparative Examples 1-5 were produced in the following procedure. In addition, in the following description, unless otherwise indicated, the value of "mass part" is a value by solid content conversion.

<Example 1>

Component (A) phosphorus acrylic resin (manufactured by DIC Corporation, product name "Acridique (registered trademark) A-817", glass transition temperature (Tg) = 95 ° C., hydroxyl value = 60 mgKOH/g, mass average molecular weight = 20,000) ) with respect to 40 parts by mass, 40 parts by mass of a methylated melamine resin as component (B) (manufactured by Allnex Japan Co., Ltd., product name “CYMEL (registered trademark)”, grade “303LF”), and both terminals hydroxyl-modified as component (C) 20 parts by mass of hydrogenated polybutadiene (manufactured by Nippon Soda Co., Ltd., product name "NISSO-PB (registered trademark)", grade "GI-2000", number average molecular weight = 2,000, bromine number = 8 g/100 g) is added, and further , 3.0 mass parts of p-toluenesulfonic acid as an acid catalyst was added with respect to a total of 100 mass parts of components (A), (B), and (C), and the release agent composition was prepared.

The coating liquid of the releasing agent composition was obtained by diluting the obtained releasing agent composition to 4.3 mass % of solid content concentration using the mixed solvent of toluene and methyl ethyl ketone (toluene:methyl ethyl ketone = 6:4 (mass ratio)).

The coating solution of the obtained release agent composition was coated on one side of a 50 μm-thick polyethylene terephthalate film (manufactured by Mitsubishi Chemical Co., Ltd., product name “DIAFoil (registered trademark)”, grade “T-100”) using a Meyer bar, A coating film was formed. The said coating film was hardened by drying at 150 degreeC for 1 minute, the 200-nm-thick peeling layer was formed, and the peeling sheet was obtained.

<Examples 2, 3, 8 and 9>

Except having changed the compounding quantity of a component (A), (B), and (C) into the quantity shown in following Table 1, it carried out similarly to Example 1, and obtained each release sheet.

<Example 4>

The acrylic resin of component (A) was an acrylic resin manufactured by Mitsui Chemicals Co., Ltd. (product name "Olesta (registered trademark)", grade "Q-828", glass transition temperature (Tg) = 135°C, hydroxyl value = 25 mgKOH) /g and mass average molecular weight = 16,500) except having changed into Example 1 similarly, and obtained the peeling sheet.

<Example 5>

The acrylic resin of the component (A) was an acrylic resin manufactured by DIC Corporation (product name "Acridique (registered trademark) A-811-BE", glass transition temperature (Tg) = 20°C, hydroxyl value = 35 mgKOH/g) , mass average molecular weight = 25,000) except having changed to 25,000), it carried out similarly to Example 1, and obtained the peeling sheet.

<Example 6>

The acrylic resin of the component (A) was an acrylic resin manufactured by DIC Corporation (product name "Acridique (registered trademark) WMU-504", glass transition temperature (Tg) = 60°C, hydroxyl value = 95 mgKOH/g, mass) A release sheet was obtained in the same manner as in Example 1 except for changing to average molecular weight = 17,000).

<Example 7>

Component (C) was modified with both terminals hydroxyl group-modified hydrogenated polyisoprene (manufactured by Idemitsu Kogsan Co., Ltd., product name "EPOL (registered trademark)", number average molecular weight = 2,500, bromine number = 5 g/100 g), except that it was changed to It carried out similarly to Example 1, and obtained the peeling sheet.

<Comparative Examples 1 to 3>

Without using component (A), except having changed the compounding quantity of component (B) and (C) into the quantity shown in following Table 1, it carried out similarly to Example 1, and obtained each release sheet.

<Comparative Examples 4 and 5>

Except having changed the compounding quantity of component (A), (B), and (C) into the quantity shown in following Table 1, it carried out similarly to Example 1, and obtained the release sheet.

The following measurement and evaluation were performed about the peeling sheet of Examples 1-9 and Comparative Examples 1-5.

[Measurement of Peeling Force]

On the release layer of the release sheet obtained in each Example and each comparative example, a polyester adhesive tape having a width of 20 mm (manufactured by Nitto Denko Co., Ltd., product number "No. 31B") was affixed using a 2 kg roller to obtain a peeling force. A sample for measurement was prepared.

30 minutes after affixing, the obtained sample was fixed in a universal tensile tester (manufactured by Shimadzu Corporation, product name "Autograph (registered trademark)", model number "AGS-20NX"), and 180° according to JIS K6854-2: 1999. The peeling force (mN/20mm) of the peeling sheet was measured by peeling the peeling layer from an adhesive tape at the speed|rate of the tensile speed of 0.3 m/min in the direction. A result is shown in Table 1.

[Evaluation of curl resistance]

In each Example and each comparative example, the sample for evaluation which respectively coated so that the thickness of a peeling layer might be set to 1 micrometer was prepared.

From the obtained sample for evaluation, a 10 cm long x 10 cm test piece was cut out, and it stored at 120 degreeC for 24 hours. After storage for 24 hours, the test piece was placed on a horizontal stand, and the lifting of the four corners of the test piece was evaluated according to the following criteria. A result is shown in Table 1.

A: The average value of the distances of the four corners of the four corners from the object is less than 3 mm.

B: The average value of the distances of the rise and fall of the four corners from the object is 3 mm or more and less than 5 mm.

C: The average value of the lifting distances of the four corners from the object is 5 mm or more.

[Evaluation of blocking resistance]

From the release sheet obtained by each Example and each comparative example, 10 pieces of 10 cm long x 10 cm long test pieces were cut out, respectively. The test pieces of 10 sheets were laminated|stacked, and it pressed on 2 Mpa and 40 degreeC conditions with a hot press machine for 24 hours. After the press, the state of blocking was visually confirmed, and the following criteria evaluated. A result is shown in Table 1.

A: The appearance of the laminated sheet after pressing maintains the same haze as before pressing, and blocking is not conspicuous.

B: The appearance of the laminated sheet after pressing partially disappears haze, and the point shows hardness blocking.

C: The appearance of the laminated sheet|seat after press lose|disappears haze in the whole surface, and shows blocking.

[Evaluation of solvent resistance]

A nonwoven fabric impregnated with methyl ethyl ketone (manufactured by Asahi Chemical Co., Ltd., trade name "Bemcoat (registered trademark)") was placed on the release layer of the release sheet obtained in each of Examples and Comparative Examples, and a load of 100 g was applied from above. It was wiped out 5 times. The surface of the release layer was visually observed and evaluated according to the following criteria. A result is shown in Table 1.

A: No change was observed on the surface of the release layer.

B: Although whitening was seen on the surface of the peeling layer, the peeling layer did not fall off completely.

C: The peeling layer was completely removed.

As shown in Table 1, it contains a component (A)-(C), and content of the said component (B) is 100 mass % of total content of a component (A), a component (B), and a component (C), 15 mass % or more and 65 mass % or less, and content of the said component (C) is 55 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C) of the release agent composition The release sheet of Examples 1 to 9 having a release layer which is a cured product is a release sheet according to Comparative Examples 1 to 3 having a release layer which is a cured product of a release agent composition that does not contain component (A), component (B) as a component ( A), the release sheet according to Comparative Example 4 having a release layer that is a cured product of a release agent composition containing less than 15 mass% in 100 mass% of the total content of the component (B) and the component (C), and the component (B) Compared to the release sheet described in Comparative Example 5, which has a release layer that is a cured product of a release agent composition containing more than 65 mass% of the total content of component (A), component (B) and component (C) of 100 mass%, conventionally, It was confirmed that both characteristics of curl resistance, blocking resistance, and solvent resistance were favorable while being able to adjust to the peeling force of the range which was difficult to obtain.

Moreover, in the peeling sheet of Comparative Examples 1-3, even when it was a case where the mixing|blending ratio of components (B) and (C) was changed, it was also confirmed that peeling force could only be adjusted within the range of fixed peeling force.

Moreover, the release sheet of Comparative Examples 1 and 5 in which content of component (B) exceeds 65 mass % among 100 mass % of total content of a component (A), a component (B), and a component (C), and 5 This inferiority was confirmed.

On the other hand, the release sheet of Comparative Example 4 in which the content of the component (B) is less than 15 mass% among 100 mass% of the total content of the component (A), the component (B) and the component (C) is inferior in solvent resistance Confirmed.

Moreover, the release sheet of Comparative Examples 2 and 3 in which content of component (C) exceeds 55 mass % among 100 mass % of total content of a component (A), a component (B), and a component (C), blocking resistance It was confirmed that the sex was inferior.

Industrial Applicability

The release sheet of the present invention can be used as a protective sheet for various pressure-sensitive adhesives such as pressure-sensitive adhesive sheets, and can be used as a process film for producing various resin sheets, ceramic green sheets, synthetic leather, various composite materials, and the like. Moreover, since the release layer of the release sheet of this invention is formed of the non-silicone type release agent composition, in the manufacturing process of the release sheet for various electronic devices or an electronic component, it is a temporary fixation or component at the time of assembly of an electronic component. It can be used suitably as a peeling sheet for adhesive sheets, such as content display.

1: release sheet
10: description
11: release layer

Claims (7)

A release sheet having a release layer and a substrate, comprising:
The release layer is a cured product of a release agent composition containing an acrylic resin (A), an amino resin (B), and a polyolefin (C) having a crosslinkable functional group;
Content of the said component (B) is 15 mass % or more and 65 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C),
The release sheet whose content of the said component (C) is 55 mass % or less in 100 mass % of total content of a component (A), a component (B), and a component (C). The method of claim 1,
The release sheet whose glass transition temperature (Tg) of the said component (A) is 10 degreeC or more. 3. The method according to claim 1 or 2,
The release sheet whose said component (B) is a melamine resin. 4. The method according to any one of claims 1 to 3,
The release sheet in which the crosslinkable functional group of the said component (C) is a hydroxyl group. 5. The method according to any one of claims 1 to 4,
The release sheet wherein the component (C) is polybutadiene having a crosslinkable functional group or polyisoprene having a crosslinkable functional group. 6. The method according to any one of claims 1 to 5,
The release sheet in which the said component (C) is hydrogenated polyolefin which has a crosslinkable functional group. 7. The method according to any one of claims 1 to 6,
The peeling sheet whose peeling force at the time of peeling from an adhesive layer is 500-4,000 mN/20mm.

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