CN116829667A - Release liner for silicone adhesive layer, and laminate and roll comprising same - Google Patents

Abstract

An object of the present disclosure is to provide a non-fluorine-based release liner having excellent releasability and heat-resistant stability of peel strength that can be applied to a silicone adhesive layer, and a laminate and a roll including the release liner. The technical means of the present disclosure is that a release liner for a silicone adhesive layer according to one embodiment of the present disclosure includes a substrate and a release layer on at least one surface of the substrate, and the release layer includes a poly (meth) acrylate that is a polymer including a polymerizable component having a (meth) acrylic acid alkyl ester monomer having a branched alkyl group having 8 or more carbon atoms.

Description

Release liner for silicone adhesive layer, and laminate and roll comprising same

Technical Field

The present disclosure relates to release liners for silicone adhesive layers, and laminates and rolls comprising the release liners.

Background

In recent years, release liners applicable to adhesive layers have been developed.

Patent document 1 (JP 2015-183041A) discloses a release film for a silicone adhesive comprising a polyvinyl acetal resin and a polymer having a structural unit derived from a monomer having a fluoroalkyl group, wherein the atomic concentration of fluorine in the vicinity of the surface of one main surface is 1.5at% to 50at%, and the difference between the atomic concentration of fluorine in the vicinity of the surface of one main surface and the atomic concentration of fluorine in the vicinity of the surface of the other main surface is 0.5at% or more.

Patent document 2 (JP 2001-240775,182) discloses a release agent article further subjected to irradiation with respect to a release agent precursor obtained by polymerizing a polymerizable composition for forming a release agent, which comprises a substrate and a release agent provided on the substrate, wherein the release agent comprises a first (meth) acrylic acid alkyl ester having an alkyl group having 12 to 30 carbon atoms, a second (meth) acrylic acid alkyl ester having an alkyl group having 1 to 12 carbon atoms, and a polymerization initiator of the first (meth) acrylic acid alkyl ester and the second (meth) acrylic acid alkyl ester, and discloses that an acrylic adhesive sheet is attached to a release sheet as the release agent article.

List of citations

Patent literature

Patent document 1: JP 2015-183041, 183041A

Patent document 2: JP 2001-240775A

Disclosure of Invention

Technical problem

The silicone adhesive generally exhibits excellent heat resistance, electrical insulation properties, chemical resistance, and the like, and can be used in a wide temperature range. When the silicone adhesive is applied to the release liner, a fluorine-based release liner is generally used, as disclosed in patent document 1.

Although fluorine-based release liners have excellent releasability to silicone adhesives, they are expensive compared to other release liners. In addition, from the viewpoint of avoiding contamination of fluorine components, there is a tendency to restrict or inhibit the use of fluorine-based materials. In addition, release liners for single sided tapes, double sided tapes, and adhesive transfer tapes comprising silicone adhesives may require heat stability of peel strength in addition to heat stability of peelability.

[ problem ] the present disclosure provides a non-fluorine-based and non-silicone-based release liner having excellent heat resistance stability of peelability and peel strength, which can be applied to a silicone adhesive layer, and a laminate and a roll including the release liner.

Solution to the problem

According to one embodiment of the present disclosure, there is provided a release liner for a silicone adhesive layer, the release liner including a substrate and a release layer on at least one surface of the substrate, and the release layer including a poly (meth) acrylate which is a polymer including a polymerizable component having a (meth) acrylic acid alkyl ester monomer having a branched alkyl group having 8 or more carbon atoms.

According to another embodiment of the present disclosure, a laminate is provided that includes a release liner and a silicone adhesive layer disposed on a release layer of the release liner.

According to another embodiment of the present disclosure, a laminate is provided that includes, in this order, a release liner, a silicone adhesive layer, and a second release liner.

According to another embodiment of the present disclosure, a roll is provided that includes a release liner including a release layer on both sides and a silicone adhesive layer.

Advantageous effects of the invention

According to the present disclosure, it is possible to provide a non-fluorine-based and non-silicone-based release liner having excellent heat resistance stability of peelability and peel strength, which can be applied to a silicone adhesive layer, and a laminate and a roll including the release liner.

The above description should not be taken to mean that all embodiments of the invention and all advantages of the invention are disclosed.

Drawings

Fig. 1 is a schematic cross-sectional view of a laminate including a release liner and a silicone adhesive layer according to one embodiment of the present disclosure.

Fig. 2 is a schematic cross-sectional view of a roll including a release liner and a silicone adhesive layer according to one embodiment of the present disclosure.

Detailed Description

Hereinafter, for the purpose of illustrating representative embodiments of the present invention, the present invention will be described in more detail with reference to the accompanying drawings as needed, but the present invention is not limited to these embodiments.

In the present disclosure, "non-fluoro-and non-silicone-based" refers to non-fluorinated and non-silicone-based. That is, the material used is not a fluorine-containing compound material, nor a silicone-based material.

In the present disclosure, "heat-resistant stability" refers to heat-resistant peel stability, for example, the peel strength of the release layer to the silicone adhesive remains stable even when the release liner is applied to the silicone adhesive and then heated or stored at high temperature.

In the present disclosure, "(meth) acrylic" means acrylic acid or methacrylic acid, "(meth) acrylate" means acrylate or methacrylate, and "(meth) acryl" means "acryl" or "methacryl".

In the present disclosure, "polymerizable component" refers to a component capable of free radical polymerization, such as a (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms.

As used herein, "curing" may also include the concept commonly referred to as "crosslinking".

In the present disclosure, for example, "on …" in "a release layer disposed on a substrate" means that the release layer is disposed directly on the substrate or that the release layer is disposed indirectly over the substrate with another layer interposed therebetween.

In the present disclosure, for example, "the order of" including the release liner, the silicone adhesive layer, and the second release liner in this order "means that when three constituent members of the release liner, the silicone adhesive layer, and the second release liner are concerned, the laminate includes these constituent members in this order, and another layer such as a print layer may be interposed between these constituent members, for example, between the silicone adhesive layer and the second release liner.

Fig. 1 is a schematic cross-sectional view of a laminate according to one embodiment of the present disclosure. The laminate 100 of fig. 1 includes, in this order, a release liner 101, a silicone adhesive layer 103, and a second release liner 105. The release liner 101 may be referred to herein as a "first release liner" to distinguish it from a second release liner. The release liner 101 and the second release liner 105 may be the same or different from each other. Although the laminate of the embodiment of fig. 1 has release liners applied to both sides of the silicone adhesive layer, in other embodiments, release liners may be applied to only one side of the silicone adhesive layer.

The release liner for a silicone adhesive layer of the present disclosure includes a release layer on at least one surface of a substrate, and the release layer includes a polymer of a polymerizable component including an alkyl (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms.

Such release layers (which may be referred to as "bnsf release layers") may reduce costs as compared to fluorine-based release layers. The bnnf release layer may exhibit substantially the same release properties with respect to the silicone adhesive layer (simply referred to as "adhesive layer") as the fluorine-based release layer, and may exhibit good release properties compared to typical silicone-based release layers. Furthermore, the bnnf peel ply may exhibit superior heat stability of peel strength as compared to the fluorine-based peel ply.

When release liners are applied to both sides of the adhesive layer, the release layers in the two release liners may be the same or different from each other, as shown in fig. 1. When the release layers are applied to both sides of the substrate of the release liner, the release layers may be the same as or different from each other. Here, when the release layers different from each other are mentioned, for example, in the case of the configuration of fig. 1, in addition to a configuration in which the release layer of the release liner 101 is a bnsf release layer and the release layer of the second release liner 105 is different in the material type of the release layer (such as a fluorine-based release layer), a configuration in which the release layers of both the release liner 101 and the second release liner 105 are bnsf release layers but the release strength of the adhesive layer with respect to the release layer of the release liner 101 and the release strength of the adhesive layer with respect to the release layer of the second release liner are different from each other is included. As shown in fig. 1, in a configuration in which the release layer has two release liners, or in a configuration in which the release layer is applied to both sides of the substrate of the release liner, if either one has a bnsf release layer, the cost can be reduced compared to a configuration in which both have a fluorine-based release layer. However, in view of avoiding contamination of the fluorine component and further reducing the cost, it is preferable that all the release layers are the bnsf release layers in any configuration.

In addition to aspects as an adhesive transfer tape as shown in fig. 1, the release liner for a silicone adhesive layer of the present disclosure may also be used as, for example, a single-sided tape or a double-sided tape. Here, in the case of a single-sided tape, typically, a release layer is provided on one side of a release liner substrate, and an adhesive is applied to the surface of the one side on which the release layer is not provided. With respect to the single-sided tape, there is also a wide mode in which a backing is provided on one side of the pressure-sensitive adhesive layer, and a release liner is provided on the opposite side of the adhesive layer (the release layer of the release liner is provided in contact with the adhesive layer). This aspect is generally used in the case of machining or the like before applying the single-sided tape to the adherend. With respect to the double-sided tape, an adhesive is applied to both sides of a backing, and a release liner is provided on the surface of the adhesive applied to both sides of the backing (such that the release layer of the release liner is in contact with the adhesive layer).

The release layer of the release liner of the present disclosure includes a polymer of a polymerizable component comprising an alkyl (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms (branched alkyl group). Such polymerizable components may be referred to as "polymerizable precursor compositions" and release agents comprising such polymers may be referred to as "(meth) acrylic release agents.

In one embodiment, such polymers have a molecular weight of about 1.0X10 at 20℃and a frequency of 1Hz ² To about 3.0X10 ⁶ Storage elastic modulus of Pa.

The storage modulus of elasticity may be about 5.0X10 ² Pa or greater, about 1.0X10 ³ Pa or greater or about 1.5X10 ³ Pa or greater, and may be about 3.0X10 ⁶ Pa or less, about 1.0X10 ⁵ Pa or less or about 1.0X10 ⁴ Pa or less.

Here, the storage elastic modulus (G') is a value measured in a shear mode at 20 ℃ and a frequency of 1Hz using a viscoelastic device (for example, TA instruments japan (TA Instruments Japan inc.), a rotameter ARES-G2).

The number of carbon atoms of the branched alkyl group may be, for example, 10 or more, 14 or more, 18 or more, 20 or more, or 24 or more, and may be 36 or less, 34 or less, 32 or less, or 30 or less from the viewpoint of peelability of the silicone adhesive layer or the like. The alkyl (meth) acrylate having a branched alkyl group containing 8 or more carbon atoms may be used alone or in combination of two or more thereof.

Branched alkyl groups containing 8 or more carbon atoms may be mono-branched or multi-branched, but are preferably mono-branched from the standpoint of peelability.

From the viewpoint of peelability, the branching position of the branched alkyl group having 8 or more carbon atoms is preferably 2 or 4.

Examples of the alkyl (meth) acrylate having a branched alkyl group having 8 or more carbon atoms include 2-ethylhexyl (meth) acrylate (8 carbon atoms), isononyl (meth) acrylate (9 carbon atoms), 2-hexyldodecyl (meth) acrylate (18 carbon atoms), 2-heptylundecyl (meth) acrylate (18 carbon atoms), 2-octyldecyl (meth) acrylate (18 carbon atoms), isostearyl (meth) acrylate (18 carbon atoms), 2-decyltetradecyl (meth) acrylate (24 carbon atoms), 2-dodecylhexadecyl (meth) acrylate (28 carbon atoms), and 2-tetradecyl octadecyl (meth) acrylate (32 carbon atoms). Such alkyl (meth) acrylates having branched side chains may lower storage elastic modulus and surface energy due to a decrease in crystallinity thereof. Among them, 2-hexyldodecyl (meth) acrylate, 2-octyldecyl (meth) acrylate, 2-decyltetradecyl (meth) acrylate, 2-dodecylhexadecyl (meth) acrylate, 2-tetradecyloctadecyl (meth) acrylate, isostearyl (meth) acrylate are preferable. The use of these prepared poly (meth) acrylates can suitably reduce the surface energy of the release layer.

The content of the alkyl (meth) acrylate monomer having a branched alkyl group having 8 or more carbon atoms in the polymerizable precursor composition may be about 40 mass% or more, about 50 mass% or more, about 60 mass% or more, about 70 mass% or more, about 80 mass% or more, about 90 mass% or more, about 95 mass% or more, or about 99 mass% or more, with respect to the total amount of the alkyl (meth) acrylate monomer components. The upper limit of such monomer content may be about 100 mass% or less, about 100 mass%, about 95 mass% or less, about 90 mass% or less, about 80 mass% or less, about 70 mass% or less, about 60 mass% or less, or about 50 mass% or less.

In one embodiment, the polymerization comprises a polymerizable component comprising an alkyl (meth) acrylate having a branched alkyl group containing 24 or more carbon atoms.

The long-chain alkyl moiety of the branched alkyl group having 24 or more carbon atoms lowers the surface energy of the cured product of the (meth) acrylic release agent, and furthermore, the alkyl group is branched, so that the crystallinity of the cured product is lowered and the storage elastic modulus of the cured product is lowered. As a result, a peeling layer exhibiting smooth (non-jump) peelability at a wide peeling speed can be formed.

Examples of the alkyl (meth) acrylate monomer having a branched alkyl group of 24 or more carbon atoms include 2-decyl tetradecyl (meth) acrylate (24 carbon atoms), 2-dodecyl hexadecyl (meth) acrylate (28 carbon atoms), and 2-tetradecyl octadecyl (meth) acrylate (32 carbon atoms). The alkyl (meth) acrylate monomer having a branched alkyl group having 24 or more carbon atoms may be used alone or in combination of two or more thereof.

Branched alkyl groups containing 24 or more carbon atoms are preferably single branched. As a result, the long chain alkyl portion of the branched alkyl group can be immobilized to form a release layer exhibiting suitable peelability with respect to the silicone adhesive layer.

The branching position of the branched alkyl group having 24 or more carbon atoms is preferably 2 or 4. As a result, crystallinity of the cured product can be effectively reduced, and smoother peelability can be obtained.

The number of carbon atoms of the branches of the branched alkyl group having 24 or more carbon atoms is preferably 8 or more, 10 or more or 12 or more. As a result, the long chain alkyl portion of the plurality of branched alkyl groups can be immobilized to form a release layer exhibiting suitable peelability with respect to the silicone adhesive layer.

The content of the alkyl (meth) acrylate monomer having a branched alkyl group having 24 or more carbon atoms in the polymerizable precursor composition may be about 90 mass% or more, about 95 mass% or more, or about 99 mass% or more with respect to the total amount of the alkyl (meth) acrylate monomer components. The upper limit of the monomer content may be about 100 mass% or less, or less than about 100 mass%.

In one embodiment, from the viewpoint of adjusting the peel strength, the polymerizable precursor composition contains an alkyl (meth) acrylate monomer having a straight-chain alkyl group in addition to the alkyl (meth) acrylate monomer having a branched alkyl group having 8 or more carbon atoms. The alkyl (meth) acrylate monomer having a straight-chain alkyl group may be used alone or in combination of two or more thereof.

The number of carbon atoms of the straight-chain alkyl group may be one or more, three or more, five or more, seven or more, ten or more or 12 or more, and may also be 24 or less, 20 or less, 18 or less, 16 or less, 14 or less or 12 or less.

Examples of the alkyl (meth) acrylate having a straight-chain alkyl group include butyl (meth) acrylate (4 carbon atoms), hexyl (meth) acrylate (6 carbon atoms), octyl (meth) acrylate (8 carbon atoms), decyl (meth) acrylate (10 carbon atoms), dodecyl (meth) acrylate (lauryl (meth) acrylate) (12 carbon atoms), tridecyl (13 carbon atoms), tetradecyl (meth) acrylate (14 carbon atoms), hexadecyl (meth) acrylate (cetyl (16 carbon atoms), octadecyl (meth) acrylate (stearyl (meth) acrylate) (18 carbon atoms), and docosyl (meth) acrylate (22 carbon atoms).

The content of the alkyl (meth) acrylate having a straight-chain alkyl group in the polymerizable precursor composition may be about 60 mass% or less, about 50 mass% or less, about 45 mass% or less, about 40 mass% or less, about 35 mass% or less, about 30 mass% or less, about 20 mass% or less, about 15 mass% or less, or about 10 mass% or less, relative to the total amount of the alkyl (meth) acrylate monomer components.

In one embodiment, the polymerizable precursor composition comprises, in addition to the alkyl (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms, a (meth) acrylate monomer having a radiation active group in the side chain. Such monomers may be blended into the polymerizable precursor composition along with the monomer components described above to form a portion of the polymer. The (meth) acrylate monomers having a radiation active group in the side chain may be used alone or in combination of two or more thereof.

Examples of the (meth) acrylate monomer having a radiation active group in the side chain include a (meth) acrylate monomer having a benzophenone structure in the side chain and a (meth) acrylate monomer having an acetophenone structure in the side chain. The radiation active groups (e.g., benzophenone structures and acetophenone structures) generate radicals by irradiation of radiation such as electron beam, ultraviolet rays, or the like. The generated radicals promote crosslinking of the polymerization product of the polymerizable precursor composition and bonding of the cured product produced by the crosslinking to the substrate. As a result, the (meth) acrylic release agent can be effectively cured with a low irradiation amount of radiation, and the cohesive strength of the cured product and the adhesiveness of the cured product to the substrate are improved, and the transfer of the cured product to the silicone adhesive is suppressed. As a result of suppressing transfer of the cured product to the silicone adhesive, the residual adhesiveness of the silicone adhesive can be maintained at a high level.

Examples of the (meth) acrylate monomer having a benzophenone structure in the side chain include 4- (meth) acryloxybenzophenone, 4- (meth) acryloxyethoxy benzophenone, 4- (meth) acryloxyethoxy-4 ' -methoxybenzophenone, 4- (meth) acryloxy4 ' -bromobenzophenone, and 4- (meth) acryloxyethoxy-4 ' -bromobenzophenone.

Examples of the (meth) acrylate monomer having an acetophenone structure in a side chain include O- (meth) acryloylacetophenone oxime.

The content of the (meth) acrylate monomer having a radiation active group in a side chain in the polymerizable precursor composition is preferably about 1 mass% or less, about 0.8 mass% or less, or about 0.5 mass% or less with respect to the total amount of the alkyl (meth) acrylate monomer components. By setting the content of the (meth) acrylate monomer having a benzophenone structure in the side chain to about 1 mass% or less, an increase in the peeling force can be suppressed. The content of the (meth) acrylate monomer having a benzophenone structure in the side chain in the polymerizable precursor composition is preferably about 0.01 mass% or more, about 0.02 mass% or more, or about 0.05 mass% or more with respect to the total amount of the alkyl (meth) acrylate monomer components. When the content of the (meth) acrylate monomer having a radiation active group in the side chain is about 0.01 mass% or more, crosslinking of the polymer (polymerization product) and bonding of the cured product to the substrate can be effectively promoted.

In one embodiment, the alkyl (meth) acrylate monomers having branched alkyl groups containing 8 or more carbon atoms and the alkyl (meth) acrylate monomers having straight alkyl groups do not have polar functional groups such as carboxyl groups, hydroxyl groups, nitrogen-containing groups (e.g., amino groups and amide groups) and phosphorus-containing groups on the alkyl groups. In this embodiment, even after the cured product has been exposed to high temperature, suitable peelability can be maintained.

In one embodiment, the (meth) acrylic release agent comprises a copolymer of an alkyl (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms, an alkyl (meth) acrylate monomer having a straight alkyl group, and a (meth) acrylate monomer having a radiation active group in a side chain. Further, as the stripping agent, a copolymer of an alkyl (meth) acrylate monomer having a branched alkyl group having 8 or more carbon atoms and an alkyl (meth) acrylate monomer having a straight-chain alkyl group and a copolymer of an alkyl (meth) acrylate monomer having a branched alkyl group having 8 or more carbon atoms and a (meth) acrylate monomer having a radiation active group in a side chain may be blended.

The polymerizable precursor composition comprising a polymerizable precursor component such as a monomer is generally polymerized in the presence of a polymerization initiator. The polymerization mode may vary, and solution polymerization by dissolving the polymerizable component in a solvent is preferable because a polymer having a high molecular weight favorable for coating formation is obtained. When solution polymerization is used, the solution of the polymerization product can be used as a (meth) acrylic polymer release agent after the polymerization is completed.

Examples of the polymerization solvent include aliphatic hydrocarbons such as n-hexane and n-heptane, esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and mixed solvents thereof. Chain transfer agents or chain extenders may also be used from the standpoint of molecular weight control.

Examples of the chain transfer agent include thiol compounds such as 2-mercaptoethanol, 3-mercapto-2-butanol, 3-mercapto-2-propanol, 3-mercapto-1-propanol, dodecanethiol, isooctyl thioglycolate, and 2-mercapto-ethylamine.

Examples of the chain extender include difunctional (meth) acrylic monomers such as 1, 6-hexanediol di (meth) acrylate, 1, 9-nonanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polypropylene glycol di (meth) acrylate.

Solution polymerization of the polymerizable precursor composition can be conducted in an inert gas atmosphere such as nitrogen for about 2 hours to about 100 hours, typically at a reaction temperature of about 50 ℃ to about 100 ℃.

As the polymerization initiator, a general polymerization initiator can be used. Examples of the polymerization initiator include azo compounds such as 2,2 '-azobisisobutyronitrile, 2' -azobis (2-methylbutyronitrile), 2-azobis (2, 4-dimethylpentanenitrile), and dimethyl 2,2 '-azobis (2-methylpropionate) (methyl 2,2' -azobis (2-methylpropionate)), and peroxides such as benzoyl peroxide and lauroyl peroxide.

The amount of the polymerization initiator used is preferably about 0.005 parts by mass or more and about 0.5 parts by mass or less based on 100 parts by mass of the alkyl (meth) acrylate monomer component. By setting the amount of the polymerization initiator to about 0.005 parts by mass or more, a practical polymerization rate can be ensured. By setting the amount of the polymerization initiator used to about 0.5 parts by mass or less, the molecular weight of the polymer can be increased to a degree sufficient for forming a coating layer.

From the viewpoints of the peeling force and the handleability of the polymerization reaction, the polymer contained in the (meth) acrylic peeling agent preferably has a weight average molecular weight of about 100000 or more, about 300000 or more or about 500000 or more, about 5000000 or less, about 4000000 or less, about 3000000 or less, about 2000000 or less, about 1500000 or less or about 1000000 or less. Here, in the present disclosure, the "weight average molecular weight" is a weight average molecular weight according to polystyrene standards as determined by a Gel Permeation Chromatography (GPC) method.

The substrate is not particularly limited, and a plastic film such as polyester (e.g., polyethylene terephthalate, polyethylene naphthalate, or polybutylene terephthalate), polyolefin (e.g., polyethylene), polyimide (e.g., kapton (trade name) available from dupont-doray co., ltd.); paper (e.g., kraft paper); or paper substrates coated with such plastic materials. A colored film may also be used as an example of the substrate. The colored film may be a mixture of dyes in plastic, colored paper, or a transparent film coated with colored ink. For example, an example of using a white film as a coloring film will be described later. By using a colored film, the user can more easily recognize the release sheet. Further, instructions on how to use, etc. may also be printed on the film. By using a colored film, the user can more easily see these printed characters and the like.

The thickness of the substrate is not particularly limited and may be, for example, about 10 microns or more, about 15 microns or more, or about 20 microns or more, and may be about 300 microns or less, about 200 microns or less, or about 150 microns or less.

The coating amount of the above-mentioned release agent may vary depending on the substrate. For example, the stripping agent is typically applied such that the dry thickness is about 0.01 microns or more and about 10 microns or less. In the case of paper substrates in which the substrate is coated with a plastic film or plastic material such as polyester and polyolefin, the dry thickness is typically about 0.05 microns or more, about 1 micron or less, and in the case of less absorbent or less smooth substrates, the dry thickness is typically about 0.1 microns or more and about 5 microns or less.

In one embodiment, the release liner is formed by: the above-mentioned release agent is coated on at least one surface of the substrate and subjected to a drying process, a curing process by heating, a curing process by radiation (e.g., electron beam and ultraviolet light), and the like.

The release liner may be manufactured, for example, by the following process. The (meth) acrylic release agent is diluted with an aliphatic hydrocarbon such as n-hexane or n-heptane, an aromatic hydrocarbon such as toluene or xylene, an ester such as ethyl acetate or butyl acetate, a ketone such as methyl ethyl ketone or methyl isobutyl ketone, a halogenated hydrocarbon such as methylene chloride or a mixed solvent thereof as required, and then applied to a substrate at a predetermined thickness using a bar coater, a roll coater, a spray coater or the like, and dried by heating as required to form a release precursor layer on the substrate. The dilution solvent may be the same as or different from the solvent in which the solution polymerization is carried out.

The release precursor layer is then irradiated with radiation, such as electron beam and ultraviolet light, to form a release layer on the substrate. The release layer is adhered to the substrate by irradiation of radiation. In this way, a release liner can be obtained. For example, in the case of electron beam irradiation, the absorbed dose depends on the thickness and composition of the release precursor layer, but is generally about 1kGy to about 100kGy. In the case of ultraviolet irradiation, the ultraviolet irradiation energy depends on the thickness and composition of the release precursor layer, but is usually about 10mJ/cm ² To about 3000mJ/cm ² Preferably about 20mJ/cm ² To about 500mJ/cm ² . Unlike electron beam irradiation, since ultraviolet irradiation does not require a large-scale device, a release liner can be manufactured at low cost and with high productivity.

The release liner of the present disclosure includes the release layer described above, and thus can exhibit suitable release properties to the silicone adhesive layer.

The silicone adhesive contained in the silicone adhesive layer that can be provided on the release layer of the release liner is not particularly limited, and examples thereof include adhesives containing polyorganosiloxane, polydimethylsiloxane, polydiphenylsiloxane, polydimethyldiphenylsiloxane, and the like as main components. These silicone adhesives may be used alone or in combination of two or more thereof.

The silicone adhesive may be of a curable type or a non-curable type. In particular, such silicone adhesives may include, for example, peroxide curable silicones, addition reactive silicones, electron beam or gamma curable silicones, and modified silicones.

Peroxide curable silicones can be used to increase cohesive strength by a curing (crosslinking) reaction as a catalyst. Addition reactive curable silicones can be used to increase cohesive strength by hydrosilylation crosslinking reactions using metal catalysts. Commercially available products are useful for peroxide curable silicone adhesives and addition reactive silicone adhesives. Commercially available peroxide curable silicone adhesives include DOWSIL (trade name) SH 4280 available from Tao Shidong, inc. (Dow Toray Co., ltd.), KR-12 available from Shin-Etsu Chemical Co., ltd.), and the like. Commercially available addition reactive silicone adhesives include DOWSIL (trade name) SD 4570 available from Tao Shidong, inc. (Dow Toray Co., ltd.), X-40-3004A available from Shin-Etsu Chemical Co., ltd.), and the like.

Examples of peroxides used as curing agents (crosslinking agents) for peroxide-curable silicone adhesives include benzoyl peroxide, diisopropylphenyl peroxide, p-chlorobenzoyl peroxide, 2, 4-dichlorobenzoyl peroxide, and di-t-butyl peroxide. The peroxides may be used alone or in combination of two or more thereof. The amount of peroxide used may be about 0.5 parts by mass to about 2.5 parts by mass per 100 parts by mass of the silicone adhesive.

Examples of metal catalysts used as curing agents (crosslinking agents) for addition-reactive silicone adhesives include platinum catalysts (e.g., chloroplatinic acid catalysts), other group VIIIB (i.e., group 8, group 9, and group 10) catalysts, and hydrosilylation catalysts. The metal catalyst may be used alone or in combination of two or more thereof. The amount of the metal catalyst used may be about 0.5 parts by mass to about 1.5 parts by mass per 100 parts by mass of the silicone adhesive.

In one embodiment, an electron beam or gamma curable silicone is used as the silicone adhesive. The silicone materials useful in electron beam or gamma curable silicones can include, for example, polydiorganosiloxanes, and such materials include a polysiloxane backbone.

As such a silicone material, a nonfunctionalized silicone material may be used. The non-functionalized silicone material may be a linear material described by the formula describing a siloxane backbone comprising aliphatic and/or aromatic substituents:

[ chemical formula 1 ]]

In formula (1), R1, R2, R3, and R4 are independently selected from alkyl groups and aryl groups, each R5 is an alkyl group, n and m are integers, and at least one of m or n is not 0. In some embodiments, one or more of the alkyl or aryl groups may include a halogen substituent (e.g., fluorine). For example, in some embodiments, one or more alkyl groups may be-CH ₂ CH ₂ C ₄ F ₉ 。

In some embodiments, R5 is a methyl group, i.e., the nonfunctionalized polydiorganosiloxane material is terminated with a trimethylsiloxy group. In some embodiments, R1 and R2 are alkyl groups and n is 0, i.e., the material is a poly (dialkylsiloxane). In some embodiments, the alkyl group is a methyl group, i.e., poly (dimethylsiloxane) ("PDMS"). In some embodiments, R1 is an alkyl group, R2 is an aryl group, and n is 0 (i.e., the material is a poly (alkylaryl siloxane)). In some embodiments, R1 is a methyl group and R2 is a phenyl group, i.e., the material is poly (methylphenyl siloxane). In some embodiments, R1 and R2 are alkyl groups and R3 and R4 are aryl groups, i.e., the material is a poly (dialkyldiaryl siloxane). In some embodiments, R1 and R2 are methyl groups and R3 and R4 are phenyl groups, i.e., the material is poly (dimethyldiphenylsiloxane).

In some embodiments, the non-functionalized polydiorganosiloxane material may be branched. For example, one or more of the R1, R2, R3, and/or R4 groups may be a linear or branched siloxane comprising an alkyl or aryl (including alkyl halide or aryl) substituent and a terminal R5 group.

In the present disclosure, a "non-functional group" is any of an alkyl or aryl group consisting of carbon, hydrogen, or (in some embodiments) halogen (e.g., fluorine) atoms. As used herein, a "non-functionalized polydiorganosiloxane material" is a material in which the R1, R2, R3, R4, and R5 groups are non-functional groups.

Typically, the functionalized silicone-based material comprises a unique reactive group (e.g., hydrogen, hydroxyl, vinyl, allyl, or acrylic groups) bonded to the polysiloxane backbone of the starting material. As used herein, "functionalized polydiorganosiloxane material" refers to a material in which at least one of the R groups in formula (2) below is a functional group.

[ chemical formula 2 ]]

In some embodiments, the functionalized polydiorganosiloxane material is a polydiorganosiloxane material in which at least two R groups are functional groups. Generally, the R groups of formula (2) are independently selectable. In some embodiments, at least one functional group is selected from the group consisting of: hydride groups, hydroxyl groups, alkoxy groups, vinyl groups, epoxy groups, and acrylate groups.

In addition to functional R groups, R groups may also be non-functional groups, such as alkyl or aryl groups, including halo (e.g., fluoro) alkyl and aryl groups. In some embodiments, the functionalized polydiorganosiloxane material may be branched. For example, one or more of the R groups may be a linear or branched siloxane bearing functional and/or non-functional substituents.

The electron beam or gamma curable silicone adhesive may be prepared as follows: one or more polydiorganosiloxane materials (e.g., silicone oils or fluids) are combined with a suitable binder-imparting resin (e.g., MQ resin) as desired, the resulting mixture is coated, and cured using electron beam (E-beam) or gamma irradiation. Generally, any known additive useful in blending adhesives may also be included.

In one embodiment, a modified silicone is used as the silicone adhesive. Here, in the present disclosure, "modified silicone" refers to a silicone to which a functional group (for example, a functional group having a urethane structure) is added to the main chain of the silicone. The modified silicone adhesive may be used alone or in combination of two or more thereof, and may be used in combination with the unmodified silicone adhesive as described above.

In one embodiment, the silicone adhesive layer comprising the modified silicone has an elastic modulus of about 2 x 10 at a temperature of-20 ℃ or less ⁵ Pa or greater, about 5×10 ⁵ Pa or greater or about 1×10 ⁶ Pa or greater, and about 7×10 ⁷ Pa or less, about 3×10 ⁷ Pa or less or about 2×10 ⁷ Pa or less. Here, the elastic modulus is a value measured using a viscoelasticity measuring device Discovery HR2 (available from TA instruments, DE, USA) under the following conditions: parallel plateThe temperature rise rate was 3℃per minute, and the measurement temperature was in the range of-65℃to 150℃and the frequency was 1Hz (6.28 rad/sec).

In one embodiment, the weight average molecular weight of the soft segment (silicone moiety) of the modified silicone contained in the silicone adhesive layer is independently 5000 or more, about 10000 or more, about 15000 or more, and about 70000 or less, about 60000 or less, or about 50000 or less.

The modified silicone is a silicone in which a functional group (for example, a functional group having a urethane structure) is imparted to the main chain of the silicone, and generally, the silicone portion constituting the main chain constitutes a soft segment, and the functional group portion constitutes a hard segment. In one embodiment, the mass ratio of soft segments to hard segments in the modified silicone contained in the silicone adhesive layer is soft segments: hard segments = about 1,000: about 1 to about 50: about 1, about 900: about 1 to about 100: about 1 or about 600: about 1 to about 200: about 1.

The modified silicone is not particularly limited and may include, for example, at least one type selected from the group consisting of: silicone polyurea block copolymers, silicone polyoxamide block copolymers, and silicone polyoxamide-hydrazide block copolymers.

In one embodiment, the silicone polyurea block copolymer comprises a polydiorganosiloxane diamine (which may be referred to as a "silicone diamine") polyisocyanate, and optionally comprises the reaction product with an organic polyamine. The silicone polyurea block copolymers may be used alone or in combination of two or more thereof.

Suitable silicone polyurea block copolymers are represented by the repeating units of formula I:

[ chemical formula 3]

In formula I, each R is independently preferably an alkyl moiety having about 1 to 12 carbon atoms, e.g., a moiety that may be substituted with a trifluoroalkyl group or a vinyl group; or preferably of formula R ² (CH ₂ ) _a CH＝CH ₂ (in the formula, R ² Is- (CH) ₂ ) _b -or (CH) ₂ ) _c Ch=ch-, a is 1, 2 or 3, b is 0, 3 or 6, c is 3, 4 or 5), cycloalkyl moieties having from about 6 to 12 carbon atoms, optionally alkylatedMoieties substituted with a group selected from the group consisting of alkyl, fluoroalkyl, and vinyl; or preferably an aryl moiety having about 6 to 20 carbon atoms, such as moieties that may be substituted with alkyl groups, cycloalkyl groups, fluoroalkyl groups, and vinyl groups; alternatively, R is a perfluoroalkyl group as disclosed in U.S. patent No. 5,028,679, a fluorine-containing group as disclosed in U.S. patent No. 5,236,997, and a perfluoropolyether group as disclosed in U.S. patent nos. 4,900,474 and 5,118,775; preferably, at least 50% of the R moieties are methyl groups, the remainder being monovalent alkyl or substituted alkyl, alkenyl groups, phenyl groups or substituted phenyl groups having from 1 to 20 carbon atoms; each Z is a polyvalent group, preferably an arylene group or aralkylene group having about 6 to 20 carbon atoms, preferably an alkylene or cycloalkylene group having about 6 to 20 carbon atoms, preferably Z is 2, 6-tolylene, 4 '-methylenediphenylene, 3' -dimethoxy-4, 4 '-biphenylene, tetramethyl-m-xylylene, 4' -methylenedicyclohexyl, 3, 5-trimethyl-3-methylenecyclohexylene, 1, 6-hexamethylene, 1, 4-cyclohexylene, 2, 4-trimethylhexylene, and mixtures thereof; each Y is independently an alkylene group having 1 to 10 carbon atoms, preferably an aralkylene group or a polyvalent group of an arylene group having 6 to 20 carbon atoms; d are each independently selected from the group consisting of: hydrogen, an alkyl group having 1 to 10 carbon atoms, a phenyl group, and a group which completes a ring structure together with B or Y to form a heterocycle; in formula I, B is a multivalent group selected from the group consisting of: alkylene, aralkylene, cycloalkylene, polyalkylene oxide (such as polyethylene oxide, polypropylene oxide, polybutylene oxide, and copolymers and mixtures thereof); m is a number from 0 to about 1,000; n is a number of at least 1; and p is a number of at least 10, preferably from about 15 to about 2,000, and more preferably from 30 to 1500.

Useful silicone polyurea block copolymers are disclosed, for example, in U.S. Pat. Nos. 5,512,650, 5,214,119 and 5,461,134, WO 96/17726, 96/34028, 96/34030 and 97/40103.

Examples of useful silicone diamines for the synthesis of silicone polyurea block copolymers include polydiorganosiloxane diamines represented by formula II below. Preferably, the polydiorganosiloxane diamine has a number average molecular weight of about 700g/mol or greater:

[ chemical formula 4 ]]

In formula II, R, Y, D and p are each as defined above.

Useful polydiorganosiloxane diamines may include any polydiorganosiloxane diamine within the scope of formula II. Wherein from the standpoint of the balance of application and peeling potential to wallpaper and member retention, polydiorganosiloxane diamines having a number average molecular weight of about 700g/mol or more, about 1000g/mol or more, about 3000g/mol or more, about 5000g/mol or more, about 10000g/mol or more, about 15000g/mol or more, about 20000g/mol or more or about 25000g/mol or more, and about 150000g/mol or less, about 100000g/mol or less, about 80000g/mol or less, about 60000g/mol or less, about 50000g/mol or less or about 40000g/mol or less can be suitably used.

Suitable synthetic methods for polydiorganosiloxane diamines and polydiorganosiloxane diamines are disclosed, for example, in U.S. Pat. Nos. 3,890,269, 4,661,577, 5,026,890, 5,276,122, WO 95/03354 and WO 96/35458.

Examples of polydiorganosiloxane diamines that may be used include polydimethylsiloxane diamine, polydiphenylsiloxane diamine, polytrifluoropropylmethylsiloxane diamine, polyphenylmethylsiloxane diamine, polydiethylsiloxane diamine, polydivinylsiloxane diamine, polyvinylmethylsiloxane diamine, poly (5-hexenyl) methylsiloxane diamine, and mixtures or copolymers thereof.

Suitable polydiorganosiloxane diamines are commercially available, for example, from SEH american hertz united states corporation of california (SEH America Inc, huls America Inc., CA). The polydiorganosiloxane diamine is preferably substantially pure and can be synthesized, for example, in a manner as disclosed in U.S. patent No. 5,214,119. Such high purity polydiorganosiloxane diamines can be synthesized by reacting a cyclic organosilane with bis (aminoalkyl) disiloxane in a two-step reaction step using an anhydrous aminoalkyl-functional silanol, such as tetramethyl ammonium-3-aminopropyl dimethyl silanol, preferably in an amount of less than 1.15 weight percent based on the total amount of cyclic organosilane. It is particularly preferred to synthesize polydiorganosiloxane diamines using cesium and rubidium catalysts, and such synthetic methods are disclosed, for example, in U.S. Pat. No. 5,512,650.

The polydiorganosiloxane diamine component can provide a means for adjusting the elastic modulus of the synthesized silicone polyurea block copolymer. Generally, high molecular weight polydiorganosiloxane diamines can produce low elastic modulus copolymers, while low molecular weight polydiorganosiloxane polyamines can produce high elastic modulus copolymers.

Examples of useful polyamines include polyoxyalkylene diamines including those available from hounsman corporation (Houston, texas) under the following trade names: JEFFAMINE (trade name) D-230 (i.e., polyoxypropylene diamine having a number average molecular weight of 230 g/mol), JEFFAMINE (trade name) D-400 (i.e., polyoxypropylene diamine having a number average molecular weight of 400 g/mol), JEFFAMIN (trade name) D-2000 (i.e., polyoxypropylene diamine having a number average molecular weight of 2,000 g/mol), JEFFAMINE (trade name) D-4000, JEFFAMINE (trade name) ED-2001, and JEFFAMINE (trade name) EDR-148 (i.e., triethylene glycol diamine); and, for example, polyoxyalkylene triamines including those available from Henschel corporation under the trade names T-403, T-3000, and T-5000; and alkylenediamines, including ethylenediamine and polyalkylene obtained from DuPont (Wilmington, delaware) of Weimington, delaware under the tradenames Dytek (trade name) A and Dytek (trade name) EP.

Any polyamine may provide a means for adjusting the elastic modulus of the copolymer. By adjusting the concentration, type and molecular weight of the organic polyamine, the modulus of elasticity of the silicone polyurea block copolymer can be adjusted.

In one embodiment, the silicone polyurea block copolymer comprises preferably about 3 moles or less, and more preferably about 0.25 moles to about 2 moles of polyamine. Preferably, the polyamine has a number average molecular weight of about 300g/mol or less.

The polyisocyanate is not particularly limited, and for example, diisocyanate and triisocyanate may be used.

Examples of suitable diisocyanates include aromatic diisocyanates such as 2, 6-toluene diisocyanate, 2, 5-toluene diisocyanate, 2, 4-toluene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, methylenebis (o-chlorophenyl diisocyanate), methylenediphenyl-4, 4 '-diisocyanate, polycarbonate diimide modified methylenediphenyl diisocyanate, (4, 4' -diisocyanate-3, 3', 5' -tetraethyl) diphenylmethane, 4 '-diisocyanato-3, 3' -dimethoxybiphenyl (o-dianisidine diisocyanate), 5-chloro-2, 4-toluene diisocyanate, and 1-chloromethyl-2, 4-diisocyanatobenzene; aromatic aliphatic diisocyanates such as meta-xylene diisocyanate and tetramethyl-meta-xylene diisocyanate; aliphatic diisocyanates such as 1, 4-diisocyanatobutane, 1, 6-diisocyanatohexane, 1, 12-diisocyanato dodecane, 2-methyl-1, 5-diisocyanato pentane; and cycloaliphatic diisocyanates such as methylene dicyclohexyl-4, 4' -diisocyanate, 3-isocyanatomethyl-3, 5-trimethylcyclohexyl isocyanate (isophorone diisocyanate), and cyclohexylidene-1, 4-diisocyanate.

Any triisocyanate capable of reacting with a polyamine, particularly a polydiorganosiloxane diamine, is suitable. Examples of such triisocyanates include polyfunctional isocyanates prepared from biurets, isocyanurates, and adducts. Examples of commercially available polyisocyanates are part of a series of polyisocyanates obtained from the Bayer group (Bayer AG) under the trade names DESMODUR (trade name) and MONDUR (trade name), from the Asahi Kabushiki Kaisha (Asahi Kasei Corporation) under the trade name DURANATE (trade name) and from the Dow Plastics under the trade name PAPI (trade name).

The polyisocyanate is preferably present in a stoichiometric amount based on the amount of polydiorganosiloxane diamine and any polyamine.

The silicone polyurea block copolymer can be synthesized, for example, by a solvent-based reaction, a solvent-free reaction, or a combination thereof. Useful solvent-based steps are, for example, "Tyagi et al" block organosiloxane copolymers:2 (Segmented Organosiloxane copolymer:2). An effective solvent-based procedure is described, for example, by the following documents: tyagi et al, "Block organosiloxane copolymer: 2.thermal and mechanical properties of silicone-Urea copolymers (Segmented Organicosiloxane Copolymers:2.Thermal and Mechanical Properties of Siloxane-Urea Copolymer), polymers, volume 25, month 12 (1984); U.S. patent No. 5214119 (Leir). Useful methods of making silicone polyurea block copolymers are also described, for example, in U.S. Pat. Nos. 5,512,650, 5,214,119, 5,461,134, WO 96/35458, WO 98/17726, WO 96/34028, and WO 97/40103.

Adhesive compositions comprising silicone polyurea block copolymers can be prepared, for example, using solvent-based reactions, solvent-free reactions, or combinations thereof.

In solvent-based reactions, the MQ resin (if present) may be introduced before, during, or after the polyamine and polyisocyanate are introduced into the reaction mixture. The reaction of the polyamine with the polyisocyanate may be carried out in a single solvent or in a mixed solvent. Preferably, the solvent is non-reactive with the polyamine and polyisocyanate. The starting materials and the end products preferably remain completely mixed in the solvent during and after the polymerization reaction has been completed. These reactions may be carried out at room temperature or at a temperature up to the boiling point of the reaction solvent. The reaction is preferably carried out at an ambient temperature of up to about 50 ℃.

When MQ resin is present, polyamine and polyisocyanate are mixed with MQ resin in a substantially solvent-free reaction in a reaction vessel, and the polyamine and polyisocyanate can be reacted to produce a silicone polyurea block copolymer, and the product can be reacted with MQ resin to produce an adhesive composition.

One useful method involving solvent-based and solventless reactions when MQ resins are present is to use the solventless reaction to prepare a silicone polyurea block copolymer, followed by mixing the silicone polyurea block copolymer and MQ resin solution in a solvent. Preferably, the silicone polyurea block copolymer-based adhesive composition can be synthesized by the combination method described above, which results in a mixture of silicone polyurea block copolymer and MQ resin.

In one embodiment, the silicone polyoxamide block copolymer and the silicone polyoxamide-hydrazide copolymer have at least two repeating units of formula a:

[ chemical formula 5 ]]

In formula A, R ¹ Each independently is alkyl, haloalkyl, aralkyl, alkenyl, aryl, or aryl substituted with alkyl, alkoxy, or halo; y is each independently alkylene, aralkylene, or a combination thereof; gs are each independently a bond or correspond to the formula R ³ HN-G-NHR ³ Subtracting two-NHR from diamine of (2) ³ Divalent residue obtained by radical R ³ Each independently is hydrogen or alkyl, or each R ³ With G and with R ³ And G both of which are bonded to form a heterocyclic group; n is each independently an integer of 0 to 1500, p is each independently an integer of 1 to 10, and q is each independently an integer of 1 or more. At least 50% of q is the integer 2.

R is suitable for use in formula A ¹ The alkyl groups of (a) typically have 1 to 10, 1 to 6 or 1 to 4 carbon atoms. Exemplary alkyl groups include, but are not limited to, methyl, ethyl, isopropyl, n-propyl, n-butyl, and isobutyl. Is suitable for R ¹ Often, the haloalkyl group of (c) has only a portion of the hydrogen atoms of the corresponding alkyl group replaced with halogen. Exemplary haloalkyl groups include chloroalkyl groups and fluoroalkyl groups having 1 to 3 halogen atoms and 3 to 10 carbon atoms. Is suitable for R ¹ Alkenyl groups of (2) often have 2 to 10 carbon atoms. Exemplary alkenyl groups often include those havingVinyl, n-propenyl and n-butenyl having 2 to 8, 2 to 6 or 2 to 4 carbon atoms. Is suitable for R ¹ Has 6 to 12 carbon atoms. Phenyl is an exemplary aryl group. The aryl group may be unsubstituted or substituted with an alkyl group (e.g., an alkyl group having 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms), an alkoxy group (e.g., an alkoxy group having 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms), or a halogen (e.g., chlorine, bromine, or fluorine). Is suitable for R ¹ Typically having an alkylene group containing 1 to 10 carbon atoms and an aryl group containing 6 to 12 carbon atoms. In some exemplary aralkyl groups, the aryl group is phenyl and the alkylene group has 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms (i.e., the structure of the aralkyl group is alkylene-phenyl, where the alkylene is bonded to the phenyl group).

In one embodiment, at least 40%, and preferably at least 50% of R in some of the repeat units of formula A ¹ The group is methyl. For example, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, or at least 99% of R ¹ The group may be methyl. The remainder R ¹ The group may be selected from alkyl, haloalkyl, aralkyl, alkenyl, aryl having at least two carbon atoms, or aryl substituted with an alkyl, alkoxy, or halo.

Y in formula A is each independently alkylene, aralkylene, or a combination thereof. Suitable alkylene groups typically have up to 10 carbon atoms, up to 8 carbon atoms, up to 6 carbon atoms, or up to 4 carbon atoms. Exemplary alkylene groups include alkylene, ethylene, propylene, and butylene. Suitable aralkylene groups typically have an arylene group of 6 to 12 carbon atoms bonded to an alkylene group of 1 to 10 carbon atoms. In some exemplary aralkylene groups, the arylene moiety is phenylene. That is, the divalent aralkylene group is phenylene-alkylene; wherein the benzene subunit is bonded to an alkylene group having 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. As used herein, with respect to Y groups, "a combination thereof" refers to a combination of two or more groups selected from alkylene groups and aralkylene groups. For example, the combination can be a single aralkylene group (e.g., alkylene-arylene-alkylene) bonded to a single alkylene group. In one exemplary alk-aryl-alk-ylidene combination, the aryl subunit is a benzene subunit and each alk has 1 to 10, 1 to 6, or 1 to 4 carbon atoms.

G in formula A is independently a bond or corresponds to R ³ HN-G-NHR ³ Removing two amino groups (i.e., -NHR) ³ A group). When G is a bond, the copolymer is a silicone polyoxamide-hydrazide. In one embodiment, G is a bond, and each R ³ Is hydrogen.

When G is a residue unit, the copolymer is a silicone polyoxamide. The diamine may have primary or secondary amino groups. R is R ³ The radical being hydrogen or alkyl (e.g. alkyl having 1 to 10, 1 to 6 or 1 to 4 carbon atoms), or R ³ And G and R ³ And the nitrogen to which both G are bonded together form a heterocyclic group (e.g., R ³ HN-G-NHR ³ Piperazine). In most embodiments, R ³ Is hydrogen or alkyl. In many embodiments, both amino groups in the diamine are primary amino groups (i.e., two R ³ All hydrogen groups), and the diamine has the formula H ₂ N-G-NH ₂ 。

In one embodiment, G is alkylene, heteroalkylene, arylene, aralkylene, or a combination thereof. Suitable alkylene groups often have 2 to 10, 2 to 6, or 2 to 4 carbon atoms. Exemplary alkylene groups include ethylene, propylene, butylene, and those groups similar to these groups. Suitable alkylene groups are often polyoxyalkylene groups such as polyoxyethylene having at least two ethylene units, polyoxypropylene having at least two propylene units or copolymers thereof. Suitable aralkylene groups typically comprise an aryl group having 6 to 12 carbon atoms bonded to an alkylene group having 1 to 10 carbon atoms. Some exemplary aralkylene groups are phenylene-alkylene; wherein the phenylene group is bonded to an alkylene group which may have 1 to 10 carbon atoms, 1 to 8 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms. As used herein, with respect to the G group, "a combination thereof" refers to a combination of two or more groups selected from alkylene, heteroalkylene, polydiorganosiloxane, arylene, and aralkylene. For example, the combination can be an aralkylene group (e.g., alkylene-arylene-alkylene) bonded to an alkylene group. In one exemplary alk-aryl-alk-ylidene combination, the aryl subunit is a benzene subunit and each alk has 1 to 10, 1 to 6, or 1 to 4 carbon atoms.

Each subscript n in formula a is independently an integer of from 0 to 1,500. For example, subscript n may be an integer of at most 1,000, at most 500, at most 400, at most 300, at most 200, at most 100, at most 80, at most 60, at most 40, at most 20, or at most 10. The value of n is often at least 1, at least 2, at least 3, at least 5, at least 10, at least 20, or at least 40. For example, subscript n may range from 40 to 1,500, 0 to 1,000, 40 to 1,000, 0 to 500, 1 to 500, 40 to 500, 1 to 400, 1 to 300, 1 to 200, 1 to 100, 1 to 80, 1 to 40, or 1 to 20.

Each subscript p is independently an integer of from 1 to 10. For example, the value of p is often an integer up to 9, up to 8, up to 7, up to 6, up to 5, up to 4, up to 3, or up to 2. The value of p may be in the range 1 to 8, 1 to 6 or 1 to 4.

Each subscript q is independently an integer of 1 or greater and at least 50% of q is the integer 2. In one embodiment, at least 75%, at least 90%, at least 99% or all q is the integer 2.

In one embodiment, the silicone polyoxamide block copolymer and the silicone polyoxamide-hydrazide block copolymer tend to be free of groups having the formula: -R ^a - (CO) -NH (wherein R ^a Is an alkylene group). All carbonylamino groups along the backbone of the copolymer material are part of a oxalylamino group (e.g., - (CO) -NH-group). That is, any carbonyl group along the backbone of the copolymer material is bonded to another carbonyl group and is part of an oxalyl group. More specifically, the copolymer comprises a plurality of aminooxalylamino groupsA bolus.

The silicone polyoxamide block copolymer and the silicone polyoxamide-hydrazide block copolymer may be linear block copolymers (i.e., comprising hard blocks and soft blocks) and elastomers. These tend to have more excellent solvent resistance than the known polydiorganosiloxane polyoxamides. Some copolymers are insoluble, for example, insoluble in toluene or even tetrahydrofuran. Here, the following method can determine whether the copolymer is "insoluble" in a particular solvent. About 1g of the sample copolymer was placed in a jar, about 100g of the desired solvent was added, the jar was sealed and left on a roller at ambient temperature for about 4 hours. A copolymer sample is considered insoluble if 90% or more of its original mass is retained after drying to constant weight.

The silicone polyoxamide block copolymer and the silicone polyoxamide-hydrazide block copolymer may be prepared, for example, according to the methods of the present disclosure. The following method may be used to make a copolymeric material having at least two repeat units of formula B:

[ chemical formula 6]

In formula B, R ¹ Each independently is alkyl, haloalkyl, aralkyl, alkenyl, aryl, or aryl substituted with alkyl, alkoxy, or halo; y is each independently alkylene, aralkylene, or a combination thereof; gs are each independently a bond or correspond to the formula R ³ HN-G-NHR ³ Subtracting two-NHR from diamine of (2) ³ Divalent residue obtained by radical R ³ Each independently is hydrogen or alkyl, or each R ³ With G and with R ³ And G both of which are bonded to form a heterocyclic group; and n is each independently an integer from 0 to 1500.

R ¹ Y, G and R ³ Similar to those described above for formula a.

The first step of the disclosed method may comprise using a compound of formula C:

[ chemical formula 7 ]]

In formula C, p is an integer of 1 to 10.

The compound of formula C comprises at least one polydiorganosiloxane segment and at least two glyoxylamino groups. R is R ¹ Y and subscript n are similar to those described for formula B, wherein p is an integer of from 1 to 10. R is R ² Each independently is an alkyl, haloalkyl or aryl group, or an aryl group substituted with an alkyl, alkoxy, halogen or alkoxycarbonyl group, or bonded via N to the following formula D:

[ chemical formula 8 ]]

In formula D, R ⁴ Each independently is hydrogen, alkyl or aryl, or R ⁴ Together forming a ring.

Is suitable for R ² The alkyl and haloalkyl groups of (a) often have 1 to 10, 1 to 6, or 1 to 4 carbon atoms. Although tertiary alkyl (e.g., tertiary butyl) and haloalkyl groups can be used, there are often primary or secondary carbon atoms directly attached (i.e., bonded) to adjacent oxygen groups. Exemplary alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, and isobutyl. Exemplary haloalkyl groups include chloroalkyl groups and fluoroalkyl groups; wherein some, but not all, of the hydrogen atoms on the corresponding alkyl groups are replaced with halogen atoms. For example, the chloroalkyl group or fluoroalkyl group may be chloromethyl, 2-chloroethyl, 2-trichloroethyl, 3-chloropropyl, 4-chlorobutyl, fluoromethyl, 2-fluoroethyl, 2-trifluoroethyl, 3-fluoropropyl, 4-fluorobutyl, and the like. Is suitable for R ² Examples of aryl groups of (a) include those having 6 to 12 carbon atoms, such as phenyl. The aryl groups may be unsubstituted or alkylated A group (e.g., an alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, or n-propyl), an alkoxy group (e.g., an alkoxy group having 1 to 4 carbon atoms such as methoxy, ethoxy, or propoxy), a halogen (e.g., chlorine, bromine, or fluorine), or an alkoxycarbonyl group (e.g., an alkoxycarbonyl group having 2 to 5 carbon atoms such as methoxycarbonyl, ethoxycarbonyl, or propoxycarbonyl).

The compound of formula C may comprise a single compound (i.e., all compounds have the same p-value and n-value), or may comprise multiple compounds (i.e., compounds have different p-values, different n-values, or both different p-values and n-values). Compounds with different values of n have siloxane chains of different lengths. Compounds with at least two p values have an extended chain.

In one embodiment, there is a mixture of a first compound of formula C (wherein subscript p equals 1) and a second compound of formula C (wherein subscript p equals at least 2). The first compound may include a plurality of different compounds having different values of n. The second compound may include a plurality of compounds having different p values, different n values, or both different p and n values. The mixture may contain at least 50 mass% of the first compound of formula C (i.e., p equals 1) and 50 mass% or less of the second compound of formula C (i.e., p equals at least 2), based on the total weight of the first and second compounds in the mixture. In some mixtures, the first compound is present in an amount of at least 55 mass%, at least 60 mass%, at least 65 mass%, at least 70 mass%, at least 75 mass%, at least 80 mass%, at least 85 mass%, at least 90 mass%, at least 95 mass%, or at least 98 mass%, based on the total amount of compounds of formula C. The mixture often contains 50 mass% or less, 45 mass% or less, 40 mass% or less, 35 mass% or less, 30 mass% or less, 25 mass% or less, 20 mass% or less, 15 mass% or less, 10 mass% or less, 5 mass% or less, or 2 mass% or less of the second compound.

In the mixture, different amounts of the compound of formula C, in which the chain is extended, can affect the final properties of the elastomeric material of formula B. That is, the amount of the second compound of formula C (i.e., p equals at least 2) can be advantageously varied to provide an elastomeric material having a range of characteristics. For example, increasing the second compound of formula C may adjust the melt rheology (e.g., make the elastomeric material more flowable when present as a melt), adjust the flexibility of the elastomeric material, decrease the elastic modulus of the elastomeric material, or achieve a combination thereof.

In the first step of the disclosed process, the compound of formula C is combined with a molar excess of a diamine of formula E below under reaction conditions.

[ chemical formula 9 ]]

R in formula E ³ The groups and G groups are similar to those described for formula B.

The diamine of formula E is optionally classified as an organic diamine or polydiorganosiloxane diamine, wherein the organic diamine is selected from, for example, an alkylene diamine, a heteroalkylene diamine, an arylene diamine, an aralkylene diamine, or an alkylene-aralkylene diamine. The diamine may have only two amino groups, such that the resulting polydiorganosiloxane polyoxamides and polyoxamide-hydrazides are linear block copolymers, often elastomers, that melt at high temperatures, and are soluble in some common organic solvents. Diamines do not have polyamines containing more than two primary or secondary amino groups. Tertiary amines that do not react with the compounds of formula C may be present.

Exemplary polyoxyalkylene diamines (i.e., G is an alkylene group in which the heteroatom is oxygen) include, but are not limited to, those commercially available from HUNTSMAN corporation (Woodlands, TX) of woodland, texas under the following trade names: JEFFAMINE (trade name) D-230, JEFFAMINE (trade name) D-400, JEFFAMINE (trade name) D-2000, and JEFFAMINE (trade name) EDR-148, as well as JEFFAMINE (trade name) HK-511 (i.e., a polyetherdiamine containing both oxyethylene groups and oxypropylene groups and having a number average molecular weight of 220 g/mol) and JEFFAMINE ED-2003 (i.e., polyethylene glycol end-protected with polypropylene oxide and having a number average molecular weight of 2000 g/mol), listed above.

Exemplary alkylenediamines (i.e., G is alkylene) include, but are not limited to, ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, 2-methylpentamethylene-1, 5-diamine (i.e., commercially available from DuPont, wilmington, DE) under the trade name DYTEK (trade name) a), 1, 3-pentanediamine (commercially available from DuPont, under the trade name DYTEK (trade name) EP), 1, 4-cyclohexanediamine, 1, 2-cyclohexanediamine (commercially available from DuPont under the trade name DHC-99), 4' -bis (aminocyclohexyl) methane, and 3-aminomethyl-3, 5-trimethylcyclohexylamine.

Exemplary arylene diamines (i.e., G is arylene, such as phenylene) include, but are not limited to, meta-phenylene diamine, ortho-phenylene diamine, and para-phenylene diamine. Exemplary aralkylene diamines (i.e., G is an aralkylene group such as alkylene-phenyl) include, but are not limited to, 4-aminomethylaniline, 3-aminomethylphenyl amine, and 2-aminomethylphenyl amine. Exemplary alkylene-aralkylene diamines (i.e., G is alkylene-aralkylene, such as alkylene-phenylene-alkylene) include, but are not limited to, 4-aminomethyl-benzylamine, 3-aminomethyl-benzylamine, and 2-aminomethyl-benzylamine.

Exemplary hydrazines (i.e., G is a chemical bond) include, but are not limited to, hydrazine and N, N' -diaminopiperidine.

In some preferred embodiments, the diamine of formula E is selected from the group consisting of: hydrazine, 1, 2-diaminoethane, 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 5-diaminopentane, 2-methyl-5-pentanediamine, 1, 6-diaminohexane and m-xylylenediamine.

Reaction of the compound of formula C with a molar excess of diamine of formula E yields an amine-terminated polymer of formula F:

[ chemical formula 10]

The reaction may be carried out using a variety of compounds of formula C, a variety of diamines, or a combination thereof. The various compounds of formula C having different number average molecular weights may be combined with a diamine or diamines under the reaction conditions. For example, the compound of formula C may include a mixture of materials having different n values, different p values, or both different n and p values. The plurality of diamines may include, for example, a first diamine that is an organic diamine, and a second diamine that is a polydiorganosiloxane diamine. Similarly, a single compound of formula C may also be combined with multiple diamines under the reaction conditions.

The condensation of the compounds of the formula C with diamines is often carried out at room temperature or at elevated temperatures, for example at temperatures up to 250 ℃. For example, the reaction can often be carried out at room temperature or at temperatures up to about 100 ℃. In other examples, the reaction may be conducted at a temperature of at least about 100 ℃, at least about 120 ℃, or at least about 150 ℃. For example, the reaction temperature is often in the range of about 100 ℃ to 220 ℃, 120 ℃ to 220 ℃, or 150 ℃ to 200 ℃. The condensation reaction is often completed in less than about 1 hour, less than about 2 hours, less than about 4 hours, less than about 8 hours, or less than about 12 hours.

The reaction may occur in the presence or absence of a solvent. Suitable solvents generally do not react with the reactants or products involved in the reaction. In addition, suitable solvents are generally capable of maintaining all reactants and all products in solution throughout the process. Exemplary solvents include, but are not limited to, toluene, tetrahydrofuran, methylene chloride, aliphatic hydrocarbons (e.g., alkanes such as hexane), or mixtures thereof.

After the reaction is complete, excess diamine and solvent (if present) are removed. Excess diamine may be removed, for example, by vacuum distillation.

The resulting amine-terminated polymer of formula F is then treated with an oxalate ester to form the repeat unit of formula F using the amine-terminated group. Useful oxalate esters have the following formula G:

[ chemical formula 11 ]]

The oxalate of formula G may be prepared, for example, by reacting a compound of formulaR ⁵ The alcohol of-OH is reacted with oxalyl dichloride. Commercially available oxalate esters of formula G (e.g., sigma-Aldrich (Milwaukee, WI)) from Sigma-Aldrich, milwaukee, WIs and VWR company (VWR International (Bristol, CT)) of Bristol, CT include, but are not limited to, dimethyl oxalate, diethyl oxalate, di-n-butyl oxalate, di-tert-butyl oxalate, diphenyl oxalate, bis (pentafluorophenyl) oxalate, 1- (2, 6-difluorophenyl) -2- (2, 3,4,5, 6-pentachlorophenyl) oxalate, and bis (2, 4, 6-trichlorophenyl) oxalate.

Particularly useful oxalate esters of formula G include, for example, oxalate esters of phenol, ethanol, butanol, methyl ethyl ketoxime, acetoxime and trifluoroethanol.

Any suitable reactor (e.g., a glass vessel or a conventional vessel equipped with a stirrer) or process may be used to prepare the silicone polyoxamide block copolymer and the silicone polyoxamide-hydrazide block copolymer according to the methods of the present disclosure. The reaction may be carried out using a batch process, a semi-batch process, or a continuous process.

At the end of the reaction, any solvent present may be removed from the polydiorganosiloxane polyoxamide or polyoxamide-hydrazide obtained. The removal process is often performed at a temperature of at least about 100 ℃, at least about 125 ℃, or at least about 150 ℃. The removal process is typically performed at a temperature of less than about 300 ℃, less than about 250 ℃, or less than about 225 ℃.

It may be desirable to conduct the reaction in the absence of a solvent. In solvents that are incompatible with both the reactants and the products, the reaction becomes incomplete and the degree of polymerization is low.

The blending amount of each of the peroxide curable silicone, the addition reactive silicone, the electron beam or γ -curable silicone, and the modified silicone in the silicone adhesive layer may independently be, for example, about 30 mass% or more, about 35 mass% or more, about 40 mass% or more, about 45 mass% or more, or about 50 mass% or more, and may be about 90 mass% or less, about 85 mass% or less, about 80 mass% or less, about 75 mass% or less, about 70 mass% or less, about 65 mass% or less, about 60 mass% or less, or about 55 mass% or less, with respect to the total amount of the adhesive layer.

The silicone adhesive layer may contain, as optional components, an adhesive imparting agent (e.g., MQ resin), an antioxidant, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a dispersant, a plasticizer, a flow improver, a surfactant, a leveling agent, a silane coupling agent, a catalyst, a filler, a pigment, a dye, and the like, as long as the effects of the present disclosure are not impaired. These optional components may be used alone or in combination of two or more thereof.

In one embodiment, the silicone adhesive layer comprises an MQ resin (which may be referred to as an "MQ tackifying resin").

Examples of useful MQ resins include at least one selected from the group consisting of: MQ silicone resins, MQD silicone resins, and MQT silicone resins. These MQ resins may have a number average molecular weight of about 100 or greater or about 500 or greater, about 50,000 or less or about 20,000 or less, and may have methyl substituents. Here, in the present disclosure, "number average molecular weight" is a number average molecular weight according to polystyrene standards as determined by a Gel Permeation Chromatography (GPC) method.

MQ silicone resins include nonfunctional resins and functional resins. The functional silicone resin has one or more functional groups including, for example, silicon-bonded hydrogen, silicon-bonded alkenyl, and silanol groups.

MQ silicone resin is a silicone resin with R' ₃ SiO _1/2 Unit (M unit) and SiO _4/2 Copolymerizable silicone resin of unit (Q unit). Such resins are disclosed in the following documents: for example, encyclopedia of polymer science and engineering (Encyclopedia of Polymer Science and Engineering), volume 15, john Weili (1989), pages 265-270; and U.S. Pat. Nos. 2,676,182 (Daudi et al), 3,627,851 (Brady), 3,772,247 (Flannigan) and 5,248,739 (Schmidt et al). For example, MQ silicone resins having functional groups are disclosed in the following documents: U.S. patent No. 4,774,310 (Butler), which discloses silyl hydride groups; U.S. Pat. No. 5,262,558(Kobayashi et al), which discloses vinyl and trifluoropropyl groups; and U.S. patent No. 4,707,531 (Shirahata), which discloses silyl cyanide and vinyl groups. The above resins are usually prepared in solvents. The dried or solventless MQ silicone resins can be prepared as disclosed in U.S. patent nos. 5,319,040 (wentrovies et al), 5,302,685 (Tsumura et al) and 4,935,484 (wolfguber et al).

MQD silicone resin is provided with R' ₃ SiO _1/2 Unit (M unit), siO _4/2 Units (Q units) and R' ₂ SiO _2/2 Terpolymers of units (D units) are described, for example, in U.S. Pat. No. 5,110,890 (Butler).

MQT silicone resin is provided with R' ₃ SiO _1/2 Unit (M unit), siO _4/2 Units (Q units) and R' SiO _3/2 Terpolymers of units (T units) (MQT resins).

MQ silicone resins are typically supplied in organic solvents. Examples of commercially available MQ silicone resins include a toluene solution of SilGrip (trade name) SR-545MQ resin available from michigan new materials japan limited (Momentive Performance Materials Japan GK) and a toluene solution of MQOH resin available from PCR corporation of ganeseville, florida (PCR, inc.). These organic solutions of MQ silicone resins may be used as provided by the suppliers, or may be dried by a number of techniques known in the art to provide MQ silicone resins having 100% non-volatile content. Examples of suitable drying methods include, but are not limited to, spray drying, oven drying, and steam separation drying.

The blending amount of the MQ resin in the adhesive layer may be, for example, about 30 mass% or more, about 35 mass% or more, about 40 mass% or more, about 45 mass% or more, or about 50 mass% or more, and may be about 70 mass% or less, about 65 mass% or less, about 60 mass% or less, about 55 mass% or less, or about 50 mass% or less, with respect to the total amount of the adhesive layer.

The silicone adhesive layer may or may not have a carrier such as paper, plastic film, nonwoven, foam layer, or the like.

The thickness of the silicone adhesive layer can be set to about 1 μm or more, about 5 μm or more, or about 10 μm or more, and about 100 μm or less, about 80 μm or less, or about 50 μm or less. Here, the thickness of the adhesive layer is an average value of the thicknesses of at least five optional positions of the adhesive layer of the laminate obtained by measuring the cross section in the thickness direction of the laminate using a scanning electron microscope. Such thickness measurement methods may also be similarly used for the thickness of the layers making up the laminate.

In one embodiment, the peel strength of the silicone adhesive layer relative to the release layer of the release liner is about 10N/25mm or less, about 7.5N/25mm or less, about 5.0N/25mm or less, about 3.0N/25mm or less, or about 1.5N/25mm or less, and about 0.01N/25mm or more, about 0.02N/25mm or more, about 0.05N/25mm or more, about 0.10N/25mm or more, or about 0.20N/25mm or more. Here, the peel strength is the peel strength when the release liner is peeled in the 180 degree direction at 300mm/min based on JIS Z0237.

The method for applying the silicone adhesive to the release liner to obtain the laminate is not particularly limited, and is, for example, a solvent coating method, an aqueous coating method, or a hot melt coating method such as a slit bar coating, doctor blade coating, roll coating, reverse roll coating, gravure coating, wire wound bar coating, slot hole coating, slot die coating, or extrusion coating. If necessary, any step such as drying or curing may be performed after the adhesive is applied to the release liner. As described above, the laminate in which the silicone adhesive is applied to the release liner can be used in tapes such as single sided tapes, double sided tapes, adhesive transfer tapes, and the like.

The tape of one embodiment includes a release liner having a release layer disposed thereon and a silicone adhesive layer laminated on the release layer of the release liner. When used in an aspect in which the adhesive layer is separated from the release sheet and attached to the adherend, the adhesive layer is also referred to as an adhesive transfer tape.

The tape of this embodiment may further include a carrier substrate such as paper, a plastic film, (meth) acrylic resin, a foam material such as polyurethane resin, a nonwoven fabric, or the like, laminated on the surface of the adhesive layer on the opposite side from the release liner. In this embodiment, in the case where the surface of the carrier substrate opposite to the surface facing the adhesive layer has a second adhesive layer, it is in the form of a so-called double-sided tape. When the surface of the support substrate opposite to the surface facing the adhesive layer does not have an adhesive layer, it is in the form of a so-called single-sided tape.

As shown in fig. 1, a laminate 100 having a configuration in which release liners are applied to both sides of a silicone adhesive layer can be manufactured, for example, by: an adhesive is applied to the release layer of the release liner 101 (first release liner) to form a silicone adhesive layer 103, and then the spaced apart second release liners 105 are bonded with the release layer interposed therebetween. Laminates having such constructions can be used, for example, as adhesive transfer tapes.

Here, the two release liners (i.e., the first release liner and the second release liner) included in the laminate having such a configuration may be the same type of release liner or different types of release liners. In one embodiment, the first and second release liners are both release liners having a bnsf release layer, and the first and second release liners may also be release liners having a fluorine-based release layer and a bnsf release layer, or a bnsf release layer and a fluorine-based release layer, respectively. Release liners having different bnnf release layers may also be used in the first and second release liners, respectively. From the standpoint of cost and avoidance of contamination by fluorine components, it is advantageous that the two release liners are release liners each having a bnnf release layer.

From the standpoint of usability of a laminate having such a configuration, it is preferable that the peel strength of the silicone adhesive layer to the release layer of the first release liner and the peel strength of the silicone adhesive layer to the release layer of the second release liner differ from each other by about 2.0 times or more, about 2.5 times or more, or about 3.0 times or more, about 20 times or less, about 10 times or less, about 5.0 times or less, about 4.5 times or less, or about 4.0 times or less. For both peel strengths, the peel strength of the first adhesive layer to the release layer of the first release liner may be higher, or the peel strength of the second adhesive layer to the release layer of the second release liner may be higher.

The roll 200 shown in fig. 2 may be manufactured, for example, by: one release layer of the release liner 201 having release layers on both sides is coated with an adhesive, and the release liner is wound into a roll while the silicone adhesive layer 203 is formed. The roll having such a structure can be used, for example, as an adhesive transfer tape or the like.

Here, the two peeling layers included in the roll body having such a configuration may be the same kind of peeling layer or different kinds of peeling layers. In one embodiment, both of the release layers are bnnf release layers, and the two release layers may be a fluorine-based release layer and a bnnf release layer or a bnnf release layer and a fluorine-based release layer, respectively. It is to be noted that different bNSNF release layers may be used for the two release layers. It is advantageous from the standpoint of cost, environmental issues, and avoidance of contamination by fluorine components that both release layers be bnnf release layers.

From the standpoint of usability of a roll body having such a configuration, it is preferable that the peel strength of the silicone adhesive layer to the release layer (first release layer) of the two release layers of the release liner and the peel strength of the silicone adhesive layer to the other release layer (second release layer) differ from each other by about 2.0 times or more, about 2.5 times or more, or about 3.0 times or more, about 20 times or less, about 10 times or less, about 5.0 times or less, about 4.5 times or less, or about 4.0 times or less. Regarding the peel strength of both, from the viewpoint of usability, the peel strength of the adhesive layer to the release layer provided on the outer peripheral side surface of the roll (i.e., the release layer on the side of symbol 201 in fig. 2) is preferably lower than the peel strength of the adhesive layer to the release layer provided on the inner peripheral side surface line of the roll (i.e., the release layer on the opposite side of symbol 201 in fig. 2).

In the release liner, laminate and roll of the present disclosure, other layers such as a print layer, a decorative layer and a concealing layer may be optionally provided within a range that does not inhibit the effects of the present disclosure. Other layers may be applied to all or part of the sides.

Examples

Specific embodiments of the present disclosure will be illustrated in the following examples; however, the present invention is not limited to these embodiments. All parts and percentages are by mass unless otherwise indicated. The values essentially comprise errors due to the measurement principle and the measurement device. The numerical values are represented by significant digits after applying ordinary rounding techniques.

Test example 1

The adhesive tape prepared using the generated release liner was inspected.

Table 1 shows the various materials used. Here, "Mw" in the table refers to weight average molecular weight. "straight-chain", "branched" and "number of carbon atoms" refer to the alkyl group of the alkyl (meth) acrylate monomer. Further, regarding HCA-32, HCA-32 (2-tetradecyl octadecyl acrylate) was synthesized from the esterification reaction of 2-tetradecyl-1-octadecanol (iso-C32 alcohol) with acryloyl chloride using the reaction conditions and purification method described in method 2 of U.S. Pat. No. 8,137,807, pages 8 to 9 (column 14, line 63 to column 15, line 8).

TABLE 1

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Precursor Polymer 1

These monomers were mixed so that the blending ratio of STA, ISA and AEBP was 50.0 parts by mass, 50.0 parts by mass and 0.2 parts by mass. The monomer mixture was diluted with an ethyl acetate/n-heptane (50 mass%/50 mass%) mixed solvent so that the monomer concentration was 50 mass%. Further, V-601 as an initiator was added in a proportion of 0.20 parts by mass with respect to the alkyl (meth) acrylate component, and the system was purged with nitrogen for 2 minutes. Then, the reaction was allowed to proceed in a constant temperature bath at 65℃for 48 hours to obtain a precursor polymer 1 of a viscous solution.

Precursor Polymer 2 to precursor Polymer 12

Precursor polymer 2 to precursor polymer 12 were obtained in the same manner as precursor polymer 1 described above, except that the formulation was changed as shown in table 2. In the precursor polymer 10, the monomer mixture was diluted with an ethyl acetate solvent to a monomer concentration of 40 mass%.

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Release liner 1

The precursor polymer 1 was diluted to 1 mass% with a mixed solvent of toluene/MEK (50 mass%/50 mass%). This dilution was coated on a polyester film (EMBLET (trade name) S-50) using a bar coater (# 04). The solvent was then evaporated to form a lift-off precursor layer having a thickness of about 0.1 microns.

The polyester film having the release precursor layer was subjected to ultraviolet irradiation at a line speed of 20m/min using an ultraviolet irradiation device (F300, medium pressure mercury lamp (H bulb), he Lishi group of Hanau, hessen, germany) to cure the release precursor layer, thereby producing a release liner 1. The amount of ultraviolet light per pass measured with a radiometer UV POWER PUCK (trade name) II from EIT at the time of irradiation was 350mJ/cm ² (UVA 168mJ/cm ² ，UVB 158mJ/cm ² And UVC 24mJ/cm ² )。

Release liner 2 to release liner 12

Release liners 2 to 12 were obtained in the same manner as in release liner 1 described above, except that the precursor polymers 2 to 12 in table 2 were used for release liners 2 to 12, respectively. Here, for the precursor polymer 8 and the precursor polymer 9, these precursor polymers were diluted to 1.06 mass% with a mixed solvent of toluene/MEK/n-heptane (34 mass%/33 mass%). In addition, for the precursor polymer 12, the precursor polymer was diluted to 1.22 mass% with a single solvent of n-heptane.

Release liner 13 and release liner 14 (release liner for PCK substrate)

With respect to the release liner 13 and the release liner 14, the release liner 13 and the release liner 14 were obtained in the same manner as in the release liner 1 described above, except that the above-described precursor polymer 1 and precursor polymer 9 were coated on PCK instead of the polyester film (emble (trade name) S-50), respectively.

Release liners 15 to 21 (release liners with white films)

With respect to the release liner 15, the release liner 15 was obtained in the same manner as in the release liner 1 described above, except that the precursor polymer 9 was coated on the white polyester film Crisper (trade name) K1212-100 instead of the polyester film (emble (trade name) S-50). With respect to the release liner 16 and the release liner 17, the release liner 16 and the release liner 17 were obtained in the same manner as in the release liner 15, except that the precursor polymer 9 was diluted to 1.5 mass% and 2.0 mass% respectively instead of 1.06 mass%. With respect to the release liner 18, the release liner 18 was obtained in the same manner as in the release liner 17, except that 2.0 mass% of the precursor polymer 1 was coated on the white polyester film (Crisper (trade name) K1212-100) instead of the precursor polymer 9. With respect to the release liner 19 and the release liner 20, the release liner 19 and the release liner 20 were obtained in the same manner as in the release liner 18, except that 2.0 mass% of the precursor polymer 1 was coated on the white polyester films diafil (trade name) W400-75 and Lumirror (trade name) #75-E20, respectively, instead of the Cripper (trade name) K1212-100. With respect to the release liner 21, the release liner 21 was obtained in the same manner as the release liner 18, except that 1.0 mass% of the precursor polymer 1 was coated on the white polyester film diafil (trade name) W100-75 instead of the Crisper (trade name) K1212-100 instead of 2.0 mass% of the precursor polymer 1.

Adhesive tape preparation using the release liner and silicone polyurea block copolymer based adhesive produced

Samples of the tapes to be evaluated used in examples and comparative examples were prepared by the following two methods.

(1) Applying an adhesive solution to the release liner produced (direct application)

First, 60 parts by mass of SPU 33K, 100 parts by mass of XR37-B1795, 180 parts by mass of toluene, and 60 parts by mass of isopropyl alcohol were mixed to prepare an adhesive solution. Here, SPU 33K was prepared in the same manner as described in example 28 of U.S. patent No. 6,569,521. The adhesive solution was coated on the manufactured release liner and dried at 105 ℃ for 10 minutes. The thickness of the dried adhesive layer was about 50 microns. The adhesive tape was obtained by applying a release liner of FD-75 onto the adhesive layer.

(2) The release liner produced was applied to an adhesive layer (dry lamination)

The above adhesive solution was coated on a release liner of FD-75 and dried at 105 ℃ for 10 minutes. The thickness of the dried adhesive layer was about 50 microns. The manufactured release liner was applied onto an adhesive layer to obtain an adhesive tape.

The produced adhesive tapes were evaluated as follows, and the results are shown in tables 3 to 6. Here, in the table, regarding the release liner, for example, release liner 1 is abbreviated as "liner 1". In addition, "NSNF group" in the table refers to non-fluoro and non-silicone based release liners prepared using alkyl (meth) acrylate monomers having a straight chain alkyl group instead of alkyl (meth) acrylate monomers having a branched chain alkyl group, and "bnsf group" refers to non-fluoro and non-silicone based release liners prepared using alkyl (meth) acrylate monomers having a branched chain alkyl group.

Peel strength test: release of adhesive layer of release liner produced to release layerStrength of

The release liner of FD-75 was peeled off from the adhesive tape, and a polyester film (cosmosfine (trade name) a 4100) was attached to the adhesive layer of the adhesive tape. Then, the polyester film and the SUS panel were bonded to each other with a double-sided tape interposed therebetween. The peel strength of the release liner thus produced was measured by using an Autograph AG-X (Shimadzu corporation (Shimadzu Corporation (Kyoto-shi, kyoto, japan)) of Kyoto City, japan) at a peeling rate of 300mm/min in a 180-degree direction. Here, when the peel strength exceeds 10N/25mm, it is described as ">10" in the table. Table 3 shows test results of the adhesive tape prepared by direct coating, table 4 shows test results when the adhesive tape prepared by direct coating was aged for several weeks at 50 ℃ and 80% RH, and table 5 shows test results of the adhesive tape prepared by direct coating and the adhesive tape prepared by dry lamination.

Residual adhesion test

After the peel strength test, the polyester film having the adhesive layer remaining on the SUS panel was peeled off from the double-sided tape, and the adhesive layer exposed on the polyester film was attached to the SUS 304 (BA) panel. The adhesion at the time of leaving the polyester film to stand at room temperature for 30 minutes and then peeling at a peeling rate of 300mm/min in a 180-degree direction was measured as residual adhesion using a precision universal tester Autograph AG-X (Shimadzu corporation (Kyoto-shi, kyoto, japan)) of Kyoto City, japan. Table 6 also shows, as reference example 1, the residual adhesiveness of the adhesive tape prepared by the above-described direct application method (1) using two fluorine-based release liners (FD-75).

From the results in table 3, it can be seen that the release layers of the non-fluoro-based and non-silicone-based bnsf release liners of the present disclosure exhibit good release properties relative to the silicone adhesive layer. Further, for example, it has also been confirmed that by adjusting the polymer composition, a release liner having low release and a release liner having high release can be manufactured, respectively.

Table 4: direct application (aging at 50deg.C, 80% RH)

From the results of table 4, it was confirmed that the non-fluorine-based and non-silicone-based bnsf release liners of the present disclosure did not affect physical properties (peel strength) even when subjected to aging treatment, and exhibited excellent wet heat stability in peel strength.

TABLE 5

From the results of table 5, it can be confirmed that the non-fluoro-based and non-silicone-based bnsf release liners of the present disclosure have equivalent physical properties (peel strength) by either the direct application method or the dry lamination method.

From the results of table 6, it was confirmed that the residual adhesiveness of the adhesive layers peeled from the non-fluorine-based and non-silicone-based bnsf release liners of the present disclosure was the same as that of the fluorine-based release liner of reference example 1.

Adhesive tape preparation using the release liner produced and silicone polyoxamide block copolymer-based adhesive

For peel strength testing and residual adhesion testing, a silicone polyoxamide block copolymer-based adhesive was used instead of a silicone polyurea block copolymer-based adhesive. First, 60 parts by mass of SPO 20K, 100 parts by mass of XR37-B1795, and 140 parts by mass of ethyl acetate were mixed to prepare a binder solution. Here, SPO 20K was prepared in the same manner as described in example 12 of U.S. Pat. No. 8,765,881. The adhesive solution was then coated on a release liner of FD-75 and dried at 105 ℃ for 10 minutes. The thickness of the dried adhesive layer was about 50 microns. Finally, the manufactured release liners (liner 1, liner 18 to liner 21) were applied onto the adhesive layer to obtain an adhesive tape, as in the dry lamination method.

The peel strength test and the residual adhesion test of the adhesive tape prepared with the silicone polyoxamide block copolymer-based adhesive were evaluated in the same manner as the adhesive tape prepared with the silicone polyurea block copolymer-based adhesive. Table 7 shows the test results of the peel strength test and the residual adhesion test.

TABLE 7

Test example 2

The heat-resistant stability of the release liner against the release strength of several silicone adhesive tapes was evaluated.

Table 8 shows the various materials used. An adhesive tape using the manufactured release liner was prepared as follows, and the heat-resistant stability of the release liner was evaluated.

Examples 38 and 39 and comparative examples 4 to 6

100 parts BY mass of DOWSIL (trade name) BY-24-740, 50 parts BY mass of toluene, 1 part BY mass of DOWSIL (trade name) BY-24-741, and 0.9 part BY mass of DOWSIL (trade name) SRX-212 were mixed to prepare an adhesive solution. The binder solution was coated on a substrate (cosmosine (trade name) a 4100) and dried at 65 ℃ for 5 minutes, and then at 120 ℃ for 3 minutes. The thickness of the dried adhesive layer was about 30 microns. The adhesive tapes of examples 38 and 39 and comparative examples 4 to 6 were obtained by applying each release liner shown in table 9 to an adhesive layer.

Examples 40 and 41 and comparative examples 7 to 9

100 parts by mass of DOWSIL (trade name) SH 4280, 50 parts by mass of toluene, and 3 parts by mass of Niper (trade name) BMT-K40 were mixed to prepare a binder solution. The binder solution was coated on a substrate (cosmosine (trade name) a 4100) and dried at 65 ℃ for 5 minutes, and then at 130 ℃ for 10 minutes. The thickness of the dried adhesive layer was about 30 microns. The adhesive tapes of examples 40 and 41 and comparative examples 7 to 9 were obtained by applying each release liner shown in table 9 to the adhesive layer.

Peel strength test

The polyester film substrate (cosmosfine (trade name) a 4100) surface of each adhesive tape manufactured as described above was adhered to the SUS panel by a double-sided tape. The peel strength of the release liner was measured at a peeling speed of 300mm/min in a 180-degree direction using an Autograph AG-X (Shimadzu corporation of Beijing City, kyoto-shi, kyoto, japan). The measurement results are shown in table 9. Here, the peel strength was measured using an adhesive tape after standing at room temperature (23 ℃ ±1 ℃ C., relative humidity 50% ±5%) for 24 hours and an adhesive tape after standing at 70 ℃ for 3 days.

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As can be seen from the results of table 9, in the adhesive tapes of examples 38, 39 and 40 and 41, the peel strength of the release liner was stable and did not change greatly after standing at room temperature and after standing at 70 ℃.

Examples 42 and 49 and comparative examples 10 to 21

Four commercially available silicone adhesive tapes, namely, a 3M (trade name) polyimide-based silicone double-sided adhesive tape 4390, a 3M (trade name) polyester tape 8403, a 3M (trade name) heat-resistant polyimide tape 5413, and a Nitoflon (trade name) 903UL were used to evaluate the heat-resistant stability of the release liner.

For the 3M (trade name) polyimide substrate silicone double-sided adhesive tape 4390, first, one liner was peeled off, and a substrate (cosmosfine (trade name) a 4100) was applied onto the adhesive layer to obtain a single-sided adhesive tape. Next, the single-sided adhesive tape and 3M (trade name) polyester tape 8403, 3M (trade name) heat-resistant polyimide tape 5413 and Nitoflon (trade name) 903UL, which are also silicone single-sided adhesive tapes, were applied to release liners shown in tables 10 to 13, respectively, to obtain adhesive tapes of examples 42 to 49 and comparative examples 10 to 21. Here, the silicone adhesive is applied to the release liner by: the silicone adhesive surface was attached to the release liner by reciprocating while pressing the silicone adhesive surface with a rubber roller having a weight of 5kg, and the laminate was left at room temperature (23 ℃ ±2 ℃ c, relative humidity 50% ±5%) for 24 hours.

The above peel strength test performed in example 38 was similarly performed on the adhesive tape, and the measurement results are shown in tables 10 to 13. Here, the peel strength was measured using an adhesive tape which was left to stand at room temperature for 24 hours, an adhesive tape which was left to stand at 100 ℃ for 12 hours, and an adhesive tape which was left to stand at 120 ℃ for 1 hour.

Table 10

TABLE 11

Table 12

TABLE 13

As can be seen from the results of tables 10 to 13, the adhesive tapes of examples 42 to 49 have very high heat-resistant stability. On the other hand, all commercially available release liners shown as comparative examples resulted in strong release forces depending on the environment.

Examples 50 to 57

As in examples 42 to 49, four commercially available silicone adhesive tapes were used to evaluate the heat resistance stability of the release liners 13 and 14. Release liners 13 and 14 were applied to the silicone adhesive surface of each of the commercially available silicone adhesive tapes shown in tables 13 to 16 in the same manner as in examples 42 to 49 to obtain adhesive tapes of examples 50 to 57.

The above peel strength test performed in example 38 was similarly performed on the adhesive tape, and the measurement results are shown in tables 14 to 17. Here, the peel strength was measured using an adhesive tape left standing at room temperature for 24 hours and an adhesive tape left standing at 70 ℃ for 3 days.

TABLE 14

TABLE 15

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Table 16

TABLE 17

According to the results of tables 14 to 17, the adhesive tapes of examples 50 to 57 had stable release forces even in the case of the PCK substrate, and had stable release forces even at high temperatures.

It will be apparent to those having skill in the art that various modifications can be made to the above-described embodiments and examples without departing from the underlying principles of the invention. Further, it will be apparent to those skilled in the art that various improvements and modifications can be made to the present invention without departing from the spirit and scope of the invention.

List of reference numerals

100. Laminate body

101. Release liner (first release liner)

103. Silicone adhesive layer

105. Second release liner

200. Rolling body

201. Release liner

203. Silicone adhesive layer

Claims (11)

1. A release liner for a silicone adhesive layer, the release liner comprising:

a substrate; and

a release layer on at least one surface of the substrate,

wherein the release layer comprises a poly (meth) acrylate and the poly (meth) acrylate is a polymer comprising a polymerizable component of an alkyl (meth) acrylate monomer having a branched alkyl group containing 8 or more carbon atoms.

2. The release liner of claim 1,

wherein the polymerizable component contains 40 mass% or more of an alkyl (meth) acrylate monomer having a branched alkyl group having 8 or more carbon atoms with respect to the total amount of the alkyl (meth) acrylate monomer components.

3. The release liner of claim 1 or 2,

wherein the polymerizable component comprises an alkyl (meth) acrylate monomer having a straight chain alkyl group.

4. The release liner of claim 1 to 3,

wherein the polymerizable component comprises a (meth) acrylate monomer having a radiation active group in a side chain.

5. The release liner of any one of claim 1 to 4,

wherein the substrate comprises paper.

6. The release liner of any one of claim 1 to 5,

wherein the substrate comprises a white film.

7. A laminate, the laminate comprising:

the release liner of any one of claims 1 to 6 and a silicone adhesive layer disposed on the release layer of the release liner.

8. The laminate according to claim 7,

wherein the silicone adhesive layer has a peel strength of 10N/25mm or less with respect to the release layer of the release liner.

9. A laminate, the laminate comprising, in this order:

the release liner according to any one of claims 1 to 6;

a silicone adhesive layer; and

and a second release liner.

10. A roll, the roll comprising:

The release liner according to any one of claims 1 to 6, comprising a release layer on both sides; and

a silicone adhesive layer.

11. Laminate according to any one of claims 7 to 9 or roll according to claim 10 for use as a single sided tape, double sided tape or adhesive transfer tape.