Peeling control agent, release film-forming silicone composition, and release substrate

Abstract

The present application relates to a peeling control agent and a release film-forming silicone composition containing the same, the peeling control agent comprising: an average unit formula: (R 1 3SiO 1 / 2 ) a (SiO 4 / 2 ) 1.0 (Wherein each R 1 is independently an alkyl group having 1 to 6 carbon atoms, and a is a number from 0.5 to 1.5) represents an organic silicone resin having a weight average molecular weight of 3000 to 6000 as measured by gel permeation chromatography in terms of a standard polystyrene; and (B) a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule; and / or (C) an alpha-olefin having 12 to 24 carbon atoms. The release film-forming silicone composition forms a release film in which the adhesion of an adhesive is small, but the adhesive is allowed to cure for a long time in a state of close contact, and the change in the peeling force is small, and the residual adhesive force of the adhesive is not reduced.

Description

Technical Field

[0001] The present invention relates to a release control agent, an organosilicon composition for forming a release film containing the release control agent, and a release substrate formed by forming a release film from the composition. Background Technology

[0002] The silicone composition for forming a release film can be coated onto the surface of various substrates such as paper and synthetic resin films, and then cured to form a film exhibiting release properties against the adhesive. For such a release film, it is required that the peeling force when peeling off the adhesive is constant, and furthermore, it is required that even after the release film and the adhesive have been in close contact for a long time, the residual adhesive force of the adhesive does not decrease.

[0003] On the other hand, in order to achieve a strong peel-off film (requiring a large peeling force), an organosilicon resin is typically incorporated as a peel control agent. For example, Patent Document 1 proposes to use R3SiO2 as a peel control agent. 1 / 2 Unit (R is a monovalent hydrocarbon group having two or fewer carbon atoms, which may be the same or different from each other) and SiO 4 / 2 The organosilicon resin, composed of unit cells, can be combined with, as needed, dibutyl maleate, decyl vinyl ether, dodecyl vinyl ether, camphene, C 16 The reactive diluents in the group consisting of -18-α-olefins and m-diisopropenylbenzene are also incorporated into a curable organosilicon composition consisting of an alkenyl diorganopolysiloxane, a methylhydropolysiloxane having silicon atoms bonded to hydrogen atoms, and a catalyst for hydrosilylation reaction. Furthermore, Patent Document 2 discloses an organosilicon composition for peelable film formation, comprising: an alkenyl diorganopolysiloxane having at least two alkenyl groups in one molecule, an organohydropolysiloxane having at least two silicon atoms bonded to hydrogen atoms in one molecule, and a composition of the formula: (CH3)3SiO 0.5 Solvent-soluble organosilicon resins composed of siloxane units represented by SiO2 and those derived from the formula: (CH3)3SiO 0.5 (CH3)2(CH2=CH)SiO 0.5 And a mixture of solvent-soluble organosilicon resins composed of siloxane units represented by SiO2, and a catalyst for addition reactions. Furthermore, Patent Document 3 discloses an organosilicon composition for exfoliating film formation, comprising: an organosilicon resin, an organopolysiloxane having at least three silicon atoms bonded to hydrogen atoms in one molecule, and a catalyst for hydrosilylation reactions, optionally incorporating an organopolysiloxane having at least two alkenyl groups in one molecule, wherein the organosilicon resin is substantially composed of the general formula: SiO2 and R'3SiO 1 / 2units, R' is a monovalent hydrocarbon group having at most three carbon atoms, a hydrogen atom, an alkenyl group, or an oxoalkenyl group, at least one R' in one molecule is the alkenyl group or the oxoalkenyl group, the R'3SiO 1 / 2 50% or less of the units are units having the alkenyl group or the oxoalkenyl group.

[0004] However, a release film formed from the silicone composition for release film formation as described above has a technical problem that it is difficult to be sufficiently re-released, and in addition, after the adhesive is long-termly adhered, the release force changes or the residual adhesive force of the adhesive decreases.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 59-084953

[0008] Patent Document 2: Japanese Patent Application Laid-Open (JP-A) No. 01-215857

[0009] Patent Document 3: Japanese Patent Application Laid-Open (JP-A) No. 07-252360 SUMMARY

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] An object of the present application is to provide a release control agent for forming a release film which, although showing a large release force against an adhesive, has a small change in release force after the adhesive is aged for a long time in an adhered state, and in addition, does not decrease the residual adhesive force of the adhesive. Further, another object of the present application is to provide a silicone composition for release film formation which is capable of forming such a release film; and a release substrate formed by forming a release film from the composition.

[0012] SOLUTION TO THE PROBLEM

[0013] The control agent of the present application is characterized by containing the following (A) component to (C) release component:

[0014] (A) having an average unit formula:

[0015] (R 1 3SiO 1 / 2 ) a (SiO 4 / 2 ) 1.0

[0016] (In the formula, each R 1 is independently an alkyl group having 1 to 6 carbon atoms, and a is a number of 0.5 to 1.5)

[0017] a silicone resin having a weight average molecular weight of 3000 to 6000 in terms of a standard polystyrene measured by gel permeation chromatography;

[0018] (B) a diorganopolysiloxane having at least two silicon atoms bonded to alkenyl groups in one molecule: 0 to 150 parts by mass relative to 100 parts by mass of the component (A); and

[0019] (C) an α-olefin having 12 to 24 carbon atoms: 0 to 200 parts by mass relative to 100 parts by mass of the component (A),

[0020] The release control agent has at least either one of the component (B) and the component (C) described above.

[0021] It is preferable that, in the release control agent described above, the component (A) is a silicone resin containing 2 to 5 mass% of a hydroxyl group bonded to a silicon atom.

[0022] Further, it is preferable that, in the release control agent described above, the component (C) is an α-olefin having 12 to 18 carbon atoms.

[0023] Further, it is preferable that the release control agent described above further contains, relative to 100 parts by mass of the component (A), at most 300 parts by mass of a component (D) which is a silicone resin represented by an average unit formula:

[0024] (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0

[0025] (in the formula, each R 2 independently is an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, and at least one R 2 is the alkenyl group in one molecule, and b is a number of 0.5 to 1.5)

[0026] a silicone resin represented by the formula.

[0027] The silicone composition for release film formation of the present application is characterized by containing the following components (I) to (IV):

[0028] (I) the release control agent described above;

[0029] (II) a diorganopolysiloxane having at least two silicon atoms bonded to alkenyl groups in one molecule: at most 400 parts by mass relative to 100 parts by mass of the total of the components (A) to (C) in the component (I);

[0030] (III) an organopolysiloxane having at least two silicon atoms bonded to hydrogen atoms in one molecule: the amount of silicon atoms bonded to hydrogen atoms in this component is 0.5 to 10 moles per 1 mole of the total of the alkenyl groups in the present composition; and

[0031] (IV) a catalyst for the hydrosilylation reaction.

[0032] It is preferable that the above composition further contains (V) a hydrosilylation reaction inhibitor in an amount of 0.001 to 5 mass% of the present composition.

[0033] It is preferable that the above composition preferably further contains (VI) an organosilicon resin represented by the average unit formula:

[0034] (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0

[0035] (in the formula, each R 2 independently is an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, wherein at least one R 2 is the alkenyl group in one molecule, and b is a number of 0.5 to 1.5)

[0036] in one molecule.

[0037] The release substrate of the present application is characterized in that it is formed of a release film formed from the above-mentioned organosilicon composition for release film formation on the surface of a film-shaped or tape-shaped base material.

[0038] Advantages

[0039] The release control agent of the present application, by being incorporated into the organosilicon composition for release film formation, enables the formation of a release film that, although exhibiting a large release force against an adhesive, shows a small change in release force after long-term aging of the adhesive in a close contact state, and in addition, does not cause a decrease in the residual adhesive force of the adhesive. Furthermore, the organosilicon composition for release film formation of the present application enables the formation of the above-mentioned release film. Moreover, the release substrate of the present application has the above-mentioned release film, and thus has the following characteristics: although exhibiting a large release force against an adhesive, shows a small change in release force after long-term aging of the adhesive in a close contact state, and in addition, does not cause a decrease in the residual adhesive force of the adhesive. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 is a cross-sectional view of the release substrate of the present application.

[0041] Figure 2 is a sectional view showing a state in which an adhesive is layered on the release substrate of the present application. DETAILED DESCRIPTION

[0042] <Definitions of Terms>

[0043] In the present specification, the "weight average molecular weight" refers to a value converted to a standard polystyrene, which is obtained by a gel permeation chromatography method. Note that, in the measurement by the gel permeation chromatography method, a measurement device uses Waters Alliance e2695 Separations Module, a column uses TSKgel Multipore HXL-M (two are used) of Tosoh, an eluent uses toluene, and a standard polystyrene uses a standard polystyrene covering a range of molecular weights of 590 to 6,770,000.

[0044] <Release Control Agent>

[0045] The release control agent of the present application is characterized by being composed of the following (A) component and (B) component:

[0046] (A) an organosilicon resin represented by the average unit formula:

[0047] (R 1 3SiO 1 / 2 ) a (SiO 4 / 2 ) 1.0

[0048] represented by the following formula:

[0049] (B) a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule, or

[0050] composed of the above (A) component and the following (C) component:

[0051] (C) an α-olefin having 12 to 24 carbon atoms,

[0052] or

[0053] composed of the above (A) component to the above (C) component.

[0054] The (A) component is a main agent of the present release control agent, and is an organosilicon resin represented by the above average unit formula. In the formula, each R 1 is independently an alkyl group having 1 to 6 carbon atoms, and specifically, examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group, and is preferably a methyl group.

[0055] Further, in the formula, a is a value representing an organosilicon resin represented by the formula: R 1 3SiO 1 / 2siloxane units represented by the formula: SiO 4 / 2 a is a number within the range of 0.5 to 1.5, preferably a number within the range of 0.6 to 1.2, or a number within the range of 0.6 to 1.0, of the molar ratio of the siloxane units represented by the formula: SiO

[0056] The weight average molecular weight of such a silicone resin, measured by gel permeation chromatography in terms of standard polystyrene, is within the range of 3000 to 6000, preferably within the range of 3000 to 5000, within the range of 4000 to 6000, or within the range of 4000 to 5000. This is because, if the weight average molecular weight of the silicone resin is above the lower limit of the above range, the resulting release film is heavy release, and on the other hand, if the weight average molecular weight of the silicone resin is below the upper limit of the above range, the coatability of the release film-forming silicone composition with the (A) component is improved.

[0057] Furthermore, such a silicone resin is preferably a silicone resin in which the silicon atoms in the molecule are bonded to hydroxyl groups, and the content of the hydroxyl groups bonded to the silicon atoms is preferably within the range of 2 to 5 mass%, within the range of 2 to 4 mass%, within the range of 2.5 to 4 mass%, or within the range of 2.5 to 3.5 mass%. This is because, if the content of the hydroxyl groups bonded to the silicon atoms in the silicone resin is within the above range, the curing reaction of the release film-forming silicone composition is facilitated, and the residual adhesion rate of the adhesive when the resulting release liner is used can be improved.

[0058] The (B) component is a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule, and is a dispersant for the (A) component. As the alkenyl group in the (B) component, examples include alkenyl groups having 2 to 6 carbon atoms such as vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, and the like, with vinyl group and hexenyl group being preferred. Furthermore, as the group other than the alkenyl group bonded to the silicon atom in the (B) component, examples include alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, and the like; aryl groups having 6 to 12 carbon atoms such as phenyl group, tolyl group, xylyl group, and the like; halogen-substituted alkyl groups having 1 to 6 carbon atoms such as 3,3,3-trifluoropropyl group, and the like, with methyl group being preferred. Furthermore, within a range that does not impair the object of the present application, the silicon atom in the (B) component can also be bonded to a small amount of alkoxyl groups having 1 to 3 carbon atoms such as hydroxyl group, methoxyl group, ethoxyl group, and the like.

[0059] (B) component, for example, straight-chain, partially branched straight-chain. Further, the viscosity at 25°C of the (B) component is not limited, and as the (B) component, a substance having a low viscosity to a substance having a high viscosity which is a gel can be used, and from the viewpoint of the dispersibility of the present release control agent, it is preferable that the viscosity be in the range of 10 to 1000 mPa-s, or in the range of 10 to 500 mPa-s. Note that the viscosity at 25°C of the (B) component can be measured by a rotational viscometer according to JIS K7117-1.

[0060] As such a (B) component, for example, dimethylvinylsiloxy-terminated dimethylpolysiloxane, dimethylvinylsiloxy-terminated dimethylsiloxane / methylvinylsiloxane copolymer, partially branched dimethylpolysiloxane having a dimethylvinylsiloxy group at one molecular chain end, partially branched dimethylpolysiloxane having a dimethylvinylsiloxy group at one molecular chain end and a trimethylsiloxy group at the other molecular chain end, trimethylsiloxy-terminated dimethylsiloxane / methylvinylsiloxane copolymer, trimethylsiloxy-terminated methylvinylsiloxane / methyl(3,3,3-trifluoropropyl)siloxane copolymer, and dimethylsiloxane / methylvinylsiloxane copolymer having a silanol group at both molecular chain ends can be exemplified.

[0061] In the present release control agent, the inclusion of the (B) component is optional, and in the case where the (C) component is not included, the inclusion of the (B) component is mandatory. Note that in the present release control agent, the content of the (B) component is in the range of 0 to 150 parts by mass relative to 100 parts by mass of the (A) component, preferably in the range of 10 to 150 parts by mass, or in the range of 20 to 100 parts by mass. This is because if the content of the (B) component is above the lower limit of the above range, the viscosity of the obtained release control agent can be reduced, the handling becomes easy, and further, the release film can be subjected to re-releasing stably. On the other hand, if the content of the (B) component is below the upper limit of the above range, the release force thereof becomes stable, and further, re-releasing can be performed with a small amount of the release control agent.

[0062] In the present release control agent, a dispersant of the above (A) component or the above (A) component and a (C) α-olefin having 12 to 24 carbon atoms for re-releasing the release film can be included. As such an α-olefin, for example, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, and preferably an α-olefin having 14 to 18 carbon atoms can be exemplified.

[0063] In the present release control agent, the inclusion of the (C) component is optional, and in the case where the (B) component is not included, the inclusion of the (C) component is mandatory. Note that the (C) component is preferably included in order to promote re-release. The content of such (C) component is not limited, and in order to promote the curing of the release film and re-release, the content of the (C) component is preferably at most 200 parts by mass, at most 180 parts by mass, at most 150 parts by mass, or at most 100 parts by mass, relative to 100 parts by mass of the (A) component.

[0064] Further, in order to adjust the release speed dependency of the release force and the like, and in order to improve the mechanical strength of the release film, the present release control agent can further include a (D) component that is an organosilicon resin represented by the average unit formula:

[0065] (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0

[0066] .

[0067] In the formula, each R 2 is independently an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, and of these, at least one R 2 is the alkenyl group. As the alkyl group of R 2 , the same groups as R 1 are exemplified, and a methyl group is preferred. Further, as the alkenyl group of R 2 , a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group are exemplified, and a vinyl group and a hexenyl group are preferred.

[0068] Further, in the formula, b is a number within a range of 0.5 to 1.5 that represents the molar ratio of the siloxane unit represented by the formula: R 2 3SiO 1 / 2 to the siloxane unit represented by the formula: SiO 4 / 2 , and is preferably a number within a range of 0.6 to 1.2 or a number within a range of 0.6 to 1.0. This is because if b is above the lower limit of the above range, the dispersibility of the present release control agent improves, and on the other hand, if b is below the upper limit of the above range, the mechanical strength of the obtained release film improves.

[0069] In the present release control agent, the content of the (D) component is not limited, and in order not to affect the release properties of the release film, the content of the (D) component is preferably at most 300 parts by mass, relative to 100 parts by mass of the (A) component. This is because if the content of the (D) component is increased, it becomes difficult to cause the release film to undergo re-release.

[0070] Further, the present release control agent can contain an organic solvent used at the time of producing the (A) component, at the time of compounding the (A) component to the (B) component, provided that the object of the present application is not impaired. As such an organic solvent, aliphatic solvents such as hexane, heptane, octane, and the like; aromatic solvents such as toluene, xylene, and the like; ketone solvents such as acetone, and the like can be exemplified. The content of the organic solvent is not limited, and in the case where the organic solvent is contained, the content of the organic solvent is preferably at most 100 parts by mass with respect to 100 parts by mass of the (A) component.

[0071] The present release control agent, by being compounded into the release film-forming organosilicon composition, can control the release force of the obtained release film against an adhesive, and become a heavy release. The curing mechanism of the release film-forming organosilicon composition is not limited, and a hydrosilylation reaction, a condensation reaction, a radical reaction, a radical reaction initiated by high-energy ray irradiation, a condensation reaction initiated by high-energy ray irradiation, or a hydrosilylation reaction initiated by high-energy ray irradiation can be exemplified, and a hydrosilylation reaction is preferred.

[0072] <Release film-forming organosilicon composition>

[0073] The release film-forming organosilicon composition of the present application is characterized by containing (I) to (IV) as follows:

[0074] (I) the above-mentioned release control agent;

[0075] (II) a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule;

[0076] (III) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule; and

[0077] (IV) a catalyst for a hydrosilylation reaction.

[0078] (I) the component is a release control agent for adjusting the release force of a release film obtained by coating the present composition on the surface of various substrates such as paper, synthetic resin films, and the like, and curing.

[0079] (I) component, or to adjust the release force, an ingredient which is a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule. As the alkenyl group in the (II) component, the same alkenyl groups as those in the (B) component can be exemplified, preferably a vinyl group, a hexenyl group. Further, as the group other than the alkenyl group in the (II) component which is bonded to the silicon atom, the same alkyl groups; aryl groups; halogen-substituted alkyl groups, preferably a methyl group, as those in the (B) component can be exemplified. Also, within a range not impairing the object of the present application, the silicon atom in the (II) component can be bonded to a small amount of a hydroxyl group, a methoxyl group, an ethoxyl group, or the like, an alkoxy group having 1 to 3 carbon atoms.

[0080] The molecular structure of the (II) component is not limited, and, for example, a straight chain, a straight chain having a part of a branched chain can be exemplified. Further, the viscosity at 25°C of the (II) component is also not limited, and, as the (II) component, a substance from a low viscosity to a substance which is gummy at a high viscosity can be used, and, from the viewpoints that the coatability of the present composition is good, and the release property of the obtained cured film is excellent, it is preferable that the viscosity is in the range of 10 to 10,000 mPa-s, or in the range of 10 to 1,000 mPa-s. Note that the viscosity at 25°C of the (II) component can be measured by a rotational viscometer according to JIS K7117-1.

[0081] As such a (II) component, the same diorganopolysiloxane as that in the (B) component can be exemplified.

[0082] In the present composition, the content of the (II) component is arbitrary, and, if there is sufficient alkenyl group-containing diorganopolysiloxane, alkenyl group-containing silicone resin in the (I) component which is required to cure the present composition, the (II) component need not be contained, and, in other cases, or to adjust the release force, or to impart softness or the like to the obtained release film, the content of the (II) component is at most 400 parts by mass, preferably at most 100 parts by mass, or at most 50 parts by mass, relative to 100 parts by mass of the total of the (A) component to the (C) component in the (I) component. This is because, if the content of the (II) component is the above upper limit or less, the obtained release film can be sufficiently cured, and re-releasability can be performed.

[0083] (III) Component is a crosslinking agent of the present composition, and is an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule. As the group bonded to the silicon atom other than the hydrogen atom in the (III) component, there can be exemplified: a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and the like alkyl groups having 1 to 6 carbon atoms; a phenyl group, a tolyl group, a xylyl group, and the like aryl groups having 6 to 12 carbon atoms; a 3,3,3-trifluoropropyl group, and the like halogen-substituted alkyl groups having 1 to 6 carbon atoms, with a methyl group being preferred. Also, within a range not impairing the object of the present application, the silicon atom in the (III) component can also be bonded to a small amount of an alkoxy group having 1 to 3 carbon atoms such as a hydroxyl group, a methoxy group, and an ethoxy group.

[0084] The molecular structure of the (III) component is not limited, and there can be exemplified: a straight chain, a straight chain having a part of a branched chain, a branched chain, a resinous shape, a ring shape, with a straight chain, a straight chain having a part of a branched chain, or a resinous shape being preferred. Also, the viscosity at 25°C of the (III) component is not limited, and is preferably within a range of 1 to 1000 mPa-s, or within a range of 5 to 200 mPa-s. Note that the viscosity at 25°C of the (III) component can be measured by a rotational viscometer in accordance with JIS K7117-1.

[0085] As such a (III) component, there can be exemplified: a methyl hydrogen polysiloxane having both ends of the molecular chain capped with a trimethylsiloxy group; a methyl hydrogen siloxane / dimethyl siloxane copolymer having both ends of the molecular chain capped with a trimethylsiloxy chain; a dimethyl hydrogen methylsiloxy capped dimethyl siloxane / methyl hydrogen siloxane copolymer having both ends of the molecular chain capped with a dimethyl hydrogen methylsiloxy group; a dimethyl polysiloxane having both ends of the molecular chain capped with a dimethyl hydrogen methylsiloxy group; a copolymer composed of siloxane units represented by the formula: H(CH3)2SiO 1 / 2 and siloxane units represented by the formula: SiO 4 / 2 ; and a copolymer composed of siloxane units represented by the formula: (CH3)3SiO 1 / 2 , siloxane units represented by the formula: H(CH3)2SiO 1 / 2 , and siloxane units represented by the formula: SiO 4 / 2 .

[0086] In the present composition, the content of the (III) component is not limited, and is within a range of 0.5 to 10 moles per 1 mole of the silicon atom-bonded hydrogen atoms in the present component relative to the total of the alkenyl groups in the present composition, preferably within a range of 1.0 to 5.0 moles, or within a range of 1.5 to 4.0 moles. This is because, if the content of the (III) component is above the lower limit of the above range, the obtained release film can be sufficiently cured, and on the other hand, if it is below the upper limit of the above range, the release force of the obtained release film becomes less likely to vary.

[0087] (IV) component is a catalyst for a hydrosilation reaction for promoting curing of the present composition, and examples thereof include platinum-based catalysts, rhodium-based catalysts, and palladium-based catalysts. In particular, from the viewpoint of being able to significantly promote curing of the present composition, the (IV) component is preferably a platinum-based catalyst. As the platinum-based catalyst, examples include platinum fine powder, chloroplatinic acid, an alcohol solution of chloroplatinic acid, a platinum-alkenylsiloxane complex, a platinum-olefin complex, and a platinum-carbonyl complex, and a platinum-alkenylsiloxane complex is particularly preferred. In the platinum-alkenylsiloxane complex, examples of the alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetra-vinylcyclotetrasiloxane, alkenylsiloxanes in which a part of the methyl groups of these alkenylsiloxanes are substituted with ethyl groups, phenyl groups, or the like, and alkenylsiloxanes in which the vinyl groups of these alkenylsiloxanes are substituted with allyl groups, hexenyl groups, or the like. In particular, from the viewpoint of the platinum-alkenylsiloxane complex having good stability, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is preferred.

[0088] In the present composition, the content of the (IV) component is not particularly limited as long as it is an amount that promotes curing of the present composition, and preferably, the amount of the catalyst metal atoms in the (IV) component is in the range of 0.01 to 1000 ppm, in terms of mass, relative to the total of the (A) component to the (D) component and the total of the (II) component to the (VI) component in the present composition, the amount is in the range of 0.01 to 500 ppm, or the amount is in the range of 0.1 to 500 ppm.

[0089] In the present composition, a small amount of a (V) hydrosilation reaction inhibitor, which is 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-phenyl-3-butyn-2-ol, 1-ethynylcyclohexan-1-ol, or the like acetylenic alcohol; (1,1-dimethyl-2-propynoxy)trimethylsilane, bis(1,1-dimethyl-2-propynoxy)dimethylsilane, bis(1,1-dimethyl-2-propynoxy)methylvinylsilane, tris(1,1-dimethyl-2-propynoxy)methylsilane, tris(1-methyl-1-phenyl-2-propynoxy)methylsilane, tetra(1,1-dimethyl-2-propynoxy)silane, (1-ethynyl-cyclohexyloxy)dimethylvinylsilane, or the like silylated acetylenic alcohol; 3-methyl-3-penten-1-yne, 3,5-dimethyl-3-hexen-1-yne, or the like ene-yne compound; 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, or the like cycloalkenylsiloxane; benzotriazole, or the like triazole compound, or the like, is preferably incorporated for the purpose of adjusting the curability of the present composition, or increasing the pot life of the present composition at room temperature. The content of such a (V) component is not limited, and is preferably in the range of 0.001 to 5 mass% of the present composition.

[0090] Further, the present composition can further contain, within a range not impairing the object of the present application, a (VI) organosilicon resin represented by the average unit formula:

[0091] (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0

[0092]

[0093] In the formula, each R 2 is independently an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, and at least one R 2 in one molecule is the alkenyl group. As the alkyl group of R 2 , the same group as R 1 is exemplified, and methyl is preferred. Further, as the alkenyl group of R 2 , vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group are exemplified, and vinyl group, hexenyl group are preferred.

[0094] Further, in the formula, b represents a siloxane unit represented by the formula: R 2 3SiO 1 / 2 and a siloxane unit represented by the formula: SiO 4 / 2 ​The number of the molar ratio of the siloxane units represented by the formula (I) is in the range of 0.5 to 1.5, preferably in the range of 0.6 to 1.2, or in the range of 0.6 to 1.0. This is because, if b is above the lower limit of the above range, the coatability of the present composition is improved, and on the other hand, if b is below the upper limit of the above range, the mechanical strength of the obtained release film is improved.

[0095] In the present composition, the content of the (VI) component is not particularly limited, and is preferably at most 80 parts by mass relative to 100 parts by mass of the total of the (A) component to the (C) component in the (I) component. This is because, if the content of the (VI) component is below the upper limit of the above range, the release properties of the obtained release film are not affected.

[0096] Further, the present composition can contain an organic solvent, as long as the object of the present application is not impaired, in order to improve the coating work of the present composition, or in order to adjust the coating amount on the surface of the substrate. As such an organic solvent, aliphatic solvents such as hexane, heptane, octane, and the like; aromatic solvents such as toluene, xylene, and the like; and ketone solvents such as acetone, and the like can be exemplified. The content of the organic solvent is not limited, and can be appropriately adjusted depending on the coating amount, and the like.

[0097] <Release Substrate>

[0098] The release substrate of the present application is characterized in that, for example, as shown in Figure 1 , a release film 2 is formed on the surface of a substrate 1 in a film shape or a tape shape, from the above-described silicone composition for forming a release film. As the substrate 1, paper such as paper, board paper, corrugated paper, glassine paper, clay-coated paper, polyolefin-laminated paper, polyethylene-laminated paper, synthetic paper, and the like; plastic films such as polyimide, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polycarbonate, polyethylene terephthalate, nylon, and the like; cloth such as natural fiber cloth, synthetic fiber cloth, artificial leather cloth, and the like; and glass wool, metal foil, and the like can be exemplified.

[0099] As a method of producing the release substrate of the present application, for example, the above-described silicone composition for forming a release film can be applied to the surface of a substrate by a gravure coating method, a bar coating method, a spray coating method, a spin coating method, a knife coating method, a roll coating method, a die coating method, and the like, and cured at room temperature or by heating, thereby forming a release film. Further, in the release substrate of the present application, the coating amount (after drying and curing) of the release film formed on the surface of the substrate is not limited, and is preferably in the range of 0.01 to 10 g / m 2 , or in the range of 0.1 to 5 g / m 2 .

[0100] The release substrate of the present application can also be, for example, as shown in Figure 2As shown, an adhesive 3 is further formed on the release film 2 formed on the surface of the base material 1. As such an adhesive 3, a silicone-based adhesive, an acrylic-based adhesive can be exemplified.

[0101] Examples

[0102] The release control agent, the silicone composition for release film formation, and the release liner according to the present application are described in detail by way of examples. Note that the method for producing the release liner and the measurement of the release force / residual adhesive rate are performed as described below.

[0103] <Method for producing release liner>

[0104] To adjust the viscosity, the silicone composition for release film formation was diluted with heptane so that the total of the components (A) to (D) and the total of the components (II) to (VI) in the composition would be 10 mass%. Using a Mayer Bar #5, the solution was applied to the surface of a polyethylene laminated Kraft paper in an amount of 0.6 to 0.8 g / m 2 after drying and curing, and cured by heating in a hot air drier at 120°C for 30 seconds to produce a release liner.

[0105] <Measurement of release force>

[0106] After the release liner produced by the above method was treated in a drier at 70°C for 3 days, a tape (Tesa 7475 tape; product name manufactured by Tesa Tape.Inc.) having a width of 25 mm was attached, and the release liner was cut into a long strip having a width of 30 mm with the tape as the center to produce a test body. A part of the test body was treated at 23°C under a load of 20 g / cm 2 for 1 day, and then, after the load was stopped and left for 30 minutes, the Tesa 7475 tape was stretched at an angle of 180° at a release speed of 0.3 m / minute using a tensile testing machine to measure the release force (gf / 25 mm). Further, the remaining test body was treated in a drier at 70°C under a load of 20 g / cm 2 for 1 day, and then, after the load was stopped and left for 30 minutes, the release force was measured in the same manner as described above.

[0107] <Residual adhesive rate>

[0108] After the release substrates prepared by the above method were treated in a dryer at 70°C for 3 days, a 38mm wide adhesive tape (polyester tape 31B; trade name manufactured by Nitto Denko Co., Ltd.) was applied. Using this tape as the center, the release substrates were cut into strips 45mm wide to create test specimens. Furthermore, as a reference, using the same tape and Teflon (registered trademark) sheets as release substrates, the same test specimens were prepared. These test specimens were then subjected to a 27g / cm² pressure in a dryer at 70°C. 2 After one day of load treatment, the film was air-cooled for approximately 30 minutes. Then, the tape was adhered to a 200 μm thick polyethylene terephthalate film and pressed twice with a 2 kg tape roller. The tape was then stretched using a tensile testing machine at a 180° angle and a peel speed of 0.3 m / min to measure the peel force (gf / 38 mm). The residual adhesion rate is defined as the ratio (%) of the adhesive force obtained in the use example with a peel substrate to the adhesive force obtained using a Teflon (registered trademark) sheet as a peel substrate.

[0109] <Examples 1-19 · Comparative Examples 1-6>

[0110] The following components are uniformly mixed in the manner shown in Tables 1 to 5 to prepare a release control agent and a release-resistant film-forming silicone composition in conjunction with the release control agent. It should be noted that the content of the catalyst for the hydrosilylation reaction in the release-resistant film-forming silicone composition is set to 100 ppm by mass, relative to the total of components (A) to (D) and components (II) to (VI) in the composition.

[0111] The silicone resin used as component (A) contains the following components.

[0112] (a-1): The weight-average molecular weight of standard polystyrene, determined by gel permeation chromatography, is 4490. (Based on the average unit formula:)

[0113] [(CH3)3SiO 1 / 2 ] 0.75 (SiO 4 / 2 ) 1.0

[0114] The indicated silicone resin (content of silicon atoms bonded to hydroxyl groups = 3.0% by mass).

[0115] (a-2): The weight-average molecular weight of standard polystyrene, determined by gel permeation chromatography, is 4900. (Based on the average unit formula:)

[0116] [(CH3)3SiO 1 / 2 ] 0.74(SiO 4 / 2 ) 1.0

[0117] an organosilicon resin represented by the formula:

[0118] (a-3) : a weight average molecular weight of 2240 in terms of a standard polystyrene, measured by a gel permeation chromatography, and having an average unit formula:

[0119] [(CH3)3SiO 1 / 2 ] 0.97 (SiO 4 / 2 ) 1.0

[0120] an organosilicon resin represented by the formula:

[0121] (a-4) : a weight average molecular weight of 6860 in terms of a standard polystyrene, measured by a gel permeation chromatography, and having an average unit formula:

[0122] [(CH3)3SiO 1 / 2 ] 0.92 (SiO 4 / 2 ) 1.0

[0123] an organosilicon resin represented by the formula:

[0124] As the diorganopolysiloxane of the component (B), the following components were used.

[0125] (b-1) : a dimethylpolysiloxane having both ends of the molecular chain dimethylvinylsiloxy-terminated, having a viscosity of 60 mPa-s, and having a content of vinyl group of 1.5 mass %.

[0126] (b-2) : a dimethylsiloxane / methylhexenylsiloxane copolymer having both ends of the molecular chain dimethylvinylsiloxy-terminated, having a viscosity of 200 mPa-s, and having a content of vinyl group of 1.1 mass %.

[0127] As the α-olefin of the component (C), the following components were used.

[0128] (c-1) : 1-hexadecene.

[0129] (c-2) : 1-tetradecene.

[0130] (c-3) : 1-octadecene.

[0131] As the component (D), the following component was used.

[0132] (d-1) : a dimethylpolysiloxane having both ends of the molecular chain dimethylvinylsiloxy-terminated, having a viscosity of 60 mPa-s, and having a content of vinyl group of 1.5 mass %.

[0133] [(CH2=CH)(CH3)2SiO 1 / 2 ] 0.05 [(CH3)3SiO 1 / 2 ] 0.43 (SiO 4 / 2 ) 0.52

[0134] Organic silicone resin represented by the formula (vinyl content = 2.0 mass %).

[0135] As the (E) organic solvent, the following ingredient was used.

[0136] (e-1): Xylene.

[0137] As the (II) component, the following ingredients were used.

[0138] (ii-1): Molecule chain both ends dimethyl vinylsiloxy-terminated dimethyl polysiloxane (vinyl content = 1.5 mass %) having a viscosity of 60 mPa-s.

[0139] (ii-2): Molecule chain both ends dimethyl vinylsiloxy-terminated dimethyl siloxane / methyl hexenyl siloxane copolymer (vinyl content = 1.1 mass %) having a viscosity of 200 mPa-s.

[0140] As the (III) component, the following ingredients were used.

[0141] (iii-1): Molecule chain both ends trimethylsiloxy-terminated methyl hydrogen polysiloxane (silicon atom-bonded hydrogen atom content = 1.6 mass %) having a viscosity of 20 mPa-s.

[0142] (iii-2): Molecule chain both ends trimethylsiloxy-terminated methyl hydrogen siloxane / dimethyl siloxane copolymer (silicon atom-bonded hydrogen atom content = 1.0 mass %) having a viscosity of 70 mPa-s.

[0143] As the (IV) component, the following ingredient was used.

[0144] (iv-1): 1,3-Divinyl tetramethyl disiloxane solution of platinum 1,3-divinyl tetramethyl disiloxane complex having a platinum concentration of 0.6 mass %.

[0145] As the (V) component, the following ingredients were used.

[0146] (v-1): 1-Ethynyl-cyclohexane-1-ol.

[0147] (v-2): 2-Methyl-3-butyn-2-ol.

[0148] As the (VI) component, the following component was used.

[0149] (vi-1): an organosilicon resin represented by the average unit formula:

[0150] [(CH2=CH)(CH3)2SiO 1 / 2 ] 0.05 [(CH3)3SiO 1 / 2 ] 0.43 (SiO 4 / 2 ) 0.52

[0151] an organosilicon resin (content of vinyl group = 2.0 mass%) represented by the following formula.

[0152] As the (VII) organic solvent, the following component was used.

[0153] (vii-1): heptane.

[0154] [Table 1]

[0155]

[0156] [Table 2]

[0157]

[0158] [Table 3]

[0159]

[0160] [Table 4]

[0161]

[0162] [Table 5]

[0163]

[0164] Industrial Applicability

[0165] The release film-forming organosilicon composition with the release control agent of the present application can form a release film in which the change in release force is small even when the adhesive is aged for a long time in a state of close adhesion, and in which the residual adhesive force of the adhesive is not reduced, and is thus suitable for applications such as adhesive labels, adhesive seals, tapes, engineering papers, optical adhesive films, and the like, which require long-term control of release properties.

[0166] Explanation of Symbols

[0167] 1: base material;

[0168] 2: release film;

[0169] 3: Adhesive.

Claims

1. A release control agent comprising the following (A) component to (C) component: (A) a silicone resin represented by the following average unit formula, having a weight average molecular weight of 3000 to 6000 in terms of a standard polystyrene measured by gel permeation chromatography: (B) a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule: 0 to 150 parts by mass per 100 parts by mass of the (A) component; and (C) an a-olefin having 12 to 24 carbon atoms: 0 to 200 parts by mass per 100 parts by mass of the (A) component, the release control agent having at least either the above (B) component or the above (C) component.

2. The release control agent according to claim 1, wherein the (A) component is a silicone resin containing 2 to 5 mass% of silicon atom-bonded hydroxyl groups. (R 1 3SiO 1 / 2 ) a (SiO 4 / 2 ) 1.0 wherein each R 1 independently is an alkyl group having 1 to 6 carbon atoms, and a is a number of 0.5 to 1.5; 3. The release control agent according to claim 1 or 2, wherein the (C) component is an a-olefin having 14 to 18 carbon atoms.

4. The release control agent according to any one of claims 1 to 3, wherein the release control agent further comprises, at most 300 parts by mass of (D) a silicone resin represented by the following average unit formula per 100 parts by mass of the (A) component:

5. A release film-forming silicone composition comprising the following (I) component to (IV) component: (I) the release control agent according to any one of claims 1 to 4; (II) a diorganopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule: at most 400 parts by mass per 100 parts by mass of the total of the (A) component to the (C) component in the (I) component; (III) an organopolysiloxane having at least two silicon atom-bonded hydrogen atoms in one molecule: the amount of silicon atom-bonded hydrogen atoms in this component is 0.5 to 10 moles per 1 mole of the total of alkenyl groups in this composition; and (IV) a catalyst for a hydrosilylation reaction.

6. The release film-forming silicone composition according to claim 5, wherein the release film-forming silicone composition further contains (V) a hydrosilylation reaction inhibitor in an amount of 0.001 to 5 mass% of this composition.

7. The release film-forming silicone composition according to claim 5 or 6, wherein the release film-forming silicone composition further contains (VI) a silicone resin represented by the following average unit formula at most 50 parts by mass per 100 parts by mass of the total of the (A) component to the (B) component in the (I) component:

8. A release substrate which is a release film formed from the release film-forming silicone composition according to any one of claims 5 to 7 on the surface of a film-shaped or tape-shaped base material. ​ ​ ​ (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0 wherein each R 2 independently is an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, wherein at least one R 2 is the alkenyl group, and b is a number from 0.5 to 1.

5. ​ ​ ​ ​ ​ ​ ​ ​ ​ (R 2 3SiO 1 / 2 ) b (SiO 4 / 2 ) 1.0 wherein each R 2 independently is an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms, wherein at least one R 2 is the alkenyl group, and b is a number from 0.5 to 1.

5. ​

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