WO2021060390A1 - Composition for covered-wire seal and covered wire - Google Patents

Abstract

Provided is a composition for a covered-wire seal, the composition containing a 2-cyanoacrylate compound that includes, with respect to the total mass of the 2-cyanoacrylate compound, 10 mass% of an alkyl-2-cyanoacrylate having an alkyl group with a carbon number of four or more, the compound also including a thickener, and the composition having a viscosity of 20-120 mPa·s at 25°C.

Description

Coated wire sealing composition and covered wire

The present invention relates to a coated electric wire sealing composition and a coated electric wire. More specifically, the present invention relates to a composition widely used as a sealing agent for a coated electric wire in wiring of various electric systems such as automobiles, home appliances and OA (Office Automation) equipment, and a coated electric wire including a cured product of the composition. It is a thing.

Various electric systems are wired by electric wires in automobiles, home appliances, OA equipment, etc., and the harness part has conventionally been crimped or sealed.

As a conventional coated electric wire sealing composition, those described in Patent Document 1 or 2 are known.
Patent Document 1 describes a composition for coating a coated electric wire, which comprises an alkyl-2-cyanoacrylate, a 2-cyanoacrylate having an ether bond at an ester residue, and a (meth) acrylate having two or more (meth) acryloyloxy groups. Has been described.
Patent Document 2 describes a coated electric wire sealing composition containing 2-cyanoacrylate containing 10% by mass or more of alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms in the main chain. There is.

Japanese Unexamined Patent Publication No. 9-118839 International Publication No. 2018/216737

According to one embodiment of the present invention, there is provided a coated electric wire sealing composition capable of obtaining a cured product having both water resistance and cold thermal impact resistance under high temperature and high humidity conditions and excellent heat resistance.
According to another embodiment of the present invention, a coated electric wire provided with a cured product of the coated electric wire sealing composition is provided.

The present invention includes the following aspects.
<1> Contains a 2-cyanoacrylate compound containing 10% by mass or more of an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms with respect to the total mass of the 2-cyanoacrylate compound, and a thickener. A composition for a coated electric wire seal having a viscosity at 25 ° C. of 20 mPa · s to 120 mPa · s.
<2> The composition for coating electric wire sealing according to <1>, wherein the content of the thickener is 1 part by mass to 12 parts by mass with respect to 100 parts by mass of the content of the 2-cyanoacrylate compound.
<3> The composition for coating electric wire sealing according to <1> or <2>, wherein the thickener is a copolymer containing a monomer unit composed of a (meth) acrylic monomer.
<4> The composition for a coated electric wire seal according to any one of <1> to <3>, wherein the thickener is an elastomer.
<5> The composition for a coated electric wire seal according to any one of <1> to <4>, wherein the thickener has a weight average molecular weight of 50,000 or more.
<6> The tip of a capillary tube having an inner diameter of 1.05 mm and a length of 120 mm is immersed in a bath solution of the coated electric wire sealing composition having a depth of 30 mm for 2 seconds and pulled up, and then the longitudinal direction of the capillary tube is changed. The coating according to any one of <1> to <5>, wherein the suction length when left to stand for 24 hours in a state of being installed so as to be horizontal to the direction of gravity is 7 mm or more and 35 mm or less. Composition for electric wire seal.
<7> Any of <1> to <6>, wherein the cured product of the coated electric wire sealing composition has a storage elastic modulus of 9.0 × 10 ⁵ Pa or more and 1.5 × 10 ^{8 Pa or less at 80 ° C.} The composition for sealing a coated electric wire according to one of the above.
<8> The 2-cyanoacrylate compound is 2-octyl-2-cyanoacrylate, 2-ethylhexyl-2-cyanoacrylate, n-octyl-2-cyanoacrylate, n-hexyl-2-cyanoacrylate, n-butyl. The composition for coating a coated electric wire according to any one of <1> to <7>, which is at least one compound selected from the group consisting of -2-cyanoacrylate and isobutyl-2-cyanoacrylate. ..
<9> The 2-cyanoacrylate compound contains alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms and / or 2-cyanoacrylate having an ether bond at an ester residue <1> to < The composition for sealing a coated electric wire according to any one of 8>.
<10> The 2-cyanoacrylate compound contains an alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms.
The content of the alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms is 10% by mass or more and 90% by mass or less with respect to the total mass of the 2-cyanoacrylate compound, <1> to The composition for sealing a coated electric wire according to any one of <9>.
<11> The 2-cyanoacrylate compound contains 2-cyanoacrylate having an ether bond at the ester residue.
Any of <1> to <10> in which the content of 2-cyanoacrylate having an ether bond in the ester residue is more than 0% by mass and 50% by mass or less with respect to the total mass of the 2-cyanoacrylate compound. The composition for sealing a coated electric wire according to one of the above.
<12> The thickener is a copolymer obtained by at least copolymerizing at least one monomer selected from the group consisting of ethylene, propylene, isoprene and butadiene with a (meth) acrylate compound. The composition for sealing a coated electric wire according to any one of <1> to <11>.
<13> The thickener is at least copolymerized with at least one monomer selected from the group consisting of ethylene, propylene, isoprene and butadiene, a (meth) acrylate compound and a monomer having a carboxy group. The composition for sealing a coated electric wire according to any one of <1> to <12>, which is a copolymer.
<14> The composition for a coated electric wire seal according to any one of <1> to <13>, further comprising a phthalic anhydride derivative represented by the following formula (1).

 

In the formula (1), R ¹ independently represents an alkyl group, an acyl group, an acyloxy group, an aryloxycarbonyl group, an aryl group, a hydroxy group, a chlorine atom, a bromine atom or an iodine atom, and n is 1 to 4 Represents an integer of.

<15> The composition for a coated electric wire seal according to any one of <1> to <14>, further comprising a plasticizer.
<16> The composition for coating electric wire sealing according to <15>, wherein the content of the plasticizer is 0.01 part by mass to 10 parts by mass with respect to 100 parts by mass of the content of the 2-cyanoacrylate compound. ..
<17> Further containing a (meth) acrylate having two or more (meth) acryloyloxy groups,
The content of the (meth) acrylate having two or more (meth) acryloyloxy groups is 1% by mass or more and 35% by mass or less with respect to the total mass of the coated electric wire sealing composition, <1> to <16> The composition for sealing a coated electric wire according to any one of.
<18> A coated electric wire comprising a cured product of the coated electric wire sealing composition according to any one of <1> to <17>.

According to one embodiment of the present invention, it is possible to provide a coated electric wire sealing composition capable of obtaining a cured product having both water resistance and cold thermal impact resistance under high temperature and high humidity conditions and excellent heat resistance.
Further, according to another embodiment of the present invention, it is possible to provide a coated electric wire provided with a cured product of the coated electric wire sealing composition.

The description of the constituent elements described below may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In the specification of the present application, "-" is used to mean that the numerical values described before and after the value are included as the lower limit value and the upper limit value, respectively.
In the numerical range described stepwise in the present specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. Good. Further, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present invention, "% by mass" and "% by weight" are synonymous, and "parts by mass" and "parts by weight" are synonymous.
Further, in the present invention, a combination of two or more preferred embodiments is a more preferred embodiment.
Further, in the present specification, "(meth) acrylic" represents both acrylic and methacrylic, or either, and "(meth) acryloyl" represents both acryloyl and methacryloyl, or either. ) Acrylic "represents both acrylate and methacrylate, or either.
In the present specification, the amount of each component in the composition is the total amount of the plurality of substances present in the composition unless otherwise specified, when a plurality of substances corresponding to each component are present in the composition. Means.
Hereinafter, an embodiment of the present invention will be described in detail.

(Composition for coated electric wire seal)
In the composition for sealing a coated electric wire of the present disclosure (hereinafter, also simply referred to as “composition”), an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms is added to the total mass of the 2-cyanoacrylate compound. On the other hand, it contains a 2-cyanoacrylate compound containing 10% by mass or more and a thickener, and has a viscosity at 25 ° C. of 20 mPa · s to 120 mPa · s.
Further, the coated electric wire sealing composition of the present disclosure can be suitably used as a coated electric wire sealing composition in wire harnesses of automobiles, home appliances, OA equipment, etc., and the coated electric wire sealing composition in automobile wire harnesses. As a thing, it can be used particularly preferably.

As a result of diligent studies by the present inventors, a composition for a coated electric wire seal capable of obtaining a cured product having both water resistance and cold heat impact resistance under high temperature and high humidity conditions and excellent heat resistance by adopting the above configuration. I found that I could provide it.
The mechanism of action of the excellent effect by this is not clear, but it is estimated as follows.
By containing an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms in an amount of 10% by mass or more based on the total mass of the 2-cyanoacrylate compound, the durability against moisture is high. A cured product having sufficient flexibility can be obtained, and a thickener is contained, and the viscosity at 25 ° C. is 20 mPa · s to 120 mPa · s, so that the flexibility, especially the flexibility at low temperature, is obtained. It is presumed that it is excellent in heat resistance.
Further, the coated electric wire sealing composition of the present disclosure contains alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms in an amount of 10% by mass or more based on the total mass of the 2-cyanoacrylate compound, and is increased. By containing a thickener, the obtained cured product is also excellent in bending resistance.

<Various physical property values of composition or cured product>
-viscosity-
The coated wire sealing composition of the present disclosure has a viscosity at 25 ° C. of 20 mPa · s to 120 mPa · s, and the obtained cured product has water resistance, cold thermal shock resistance, heat resistance, and heat resistance under high temperature and high humidity conditions. From the viewpoint of bending resistance, it is preferably 25 mPa · s to 100 mPa · s, more preferably 30 mPa · s to 80 mPa · s, and particularly preferably 35 mPa · s to 60 mPa · s.

The method for measuring the viscosity of the coated wire sealing composition of the present disclosure at 25 ° C. is a TVE-20H type viscometer (salt water / flat plate method, Toki Sangyo Co., Ltd.) which is an E type viscometer (cone plate type viscometer). The viscosity is measured under the following conditions.
-Measurement condition-
Cone shape: Angle 1 ° 34', radius 24 mm
Temperature: 25 ° C ± 0.5 ° C

-Sucking length-
The composition for sealing a coated electric wire of the present disclosure is 20 mPa · s to 120 mPa · s, and from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. The tip of the capillary tube having an inner diameter of 1.05 mm and a length of 120 mm is immersed in a bath solution of the coated electric wire sealing composition having a depth of 30 mm for 2 seconds and pulled up, and then the longitudinal direction of the capillary tube is set in the direction of gravity. The suction length when left to stand for 24 hours in a state of being installed so as to be in the horizontal direction is preferably 7 mm or more and 35 mm or less, more preferably 10 mm or more and 32 mm or less, and 13 mm or more and 25 mm or less. Is particularly preferable.
The suction length is measured at 23 ° C. ± 0.5 ° C., and the capillary tube is made of borosilicate glass.

-Storage modulus-
The storage elastic modulus of the cured product of the coated wire sealing composition of the present disclosure at 80 ° C. ^{is preferably 9.0 × 10 5} Pa or more and 1.5 × 10 ⁸ Pa or less, preferably 9.0 × 10 ⁵ Pa. It is more preferably 5.0 × 10 ⁷ Pa or more, and particularly preferably 9.0 × 10 ⁵ Pa or more and 5.0 × 10 ⁶ Pa or less.

The storage elastic modulus of the cured product of the coated wire sealing composition of the present disclosure at 80 ° C. shall be measured as follows using MCR 301 manufactured by Antonio Par.
After applying a curing accelerator solution (ethanol solution of 5% by mass N, N'-dimethylparatoluidine) to both sides of the upper and lower parallel plates and drying, apply an appropriate amount of the composition to the lower plate and immediately apply the upper plate. To descend. Then, it is left at 25 ° C. for 2 hours, and the storage elastic modulus at 80 ° C. is measured under the conditions of strain 0.1%, frequency 1 Hz, heating rate 2 ° C./min, and initial gap 300 μm.

<2-Cyanoacrylate compound>
The composition for sealing a coated electric wire of the present disclosure contains an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms in an amount of 10% by mass or more based on the total mass of the 2-cyanoacrylate compound. including.
The composition for sealing a coated electric wire of the present disclosure contains an alkyl group having 4 or more carbon atoms as a 2-cyanoacrylate compound even if it contains only an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms. Alkyl-2-cyanoacrylate having and other 2-cyanoacrylate compound may be contained.

The content of the 2-cyanoacrylate compound in the coated wire sealing composition of the present disclosure is determined from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. It is preferably 50% by mass to 99.8% by mass, more preferably 70% by mass to 99.5% by mass, and 80% by mass to 99% by mass with respect to the total mass of the composition. It is more preferably 85% by mass to 97% by mass.

<< Alkyl-2-cyanoacrylate having an alkyl group with 4 or more carbon atoms >>
Various alkyl-2-cyanoacrylates having an alkyl group having 4 or more carbon atoms in the main chain, which is a constituent component of the composition of the present disclosure, can be used. The upper limit of the number of carbon atoms in the main chain is not particularly limited, but can be, for example, 12 or less. The upper limit of the number of carbon atoms in the main chain is preferably 8 or less. Specific examples include n-butyl-2-cyanoacrylate, 2-butyl-2-cyanoacrylate, isobutyl-2-cyanoacrylate (2-methylpropyl-2-cyanoacrylate), n-hexyl-2-cyanoacrylate, and the like. n-Heptyl-2-cyanoacrylate, 1-methylpentyl-2-cyanoacrylate, n-octyl-2-cyanoacrylate, 2-octyl-2-cyanoacrylate, 2-ethylhexyl-2-cyanoacrylate, n-nonyl- Examples thereof include 2-cyanoacrylate, isononyl-2-cyanoacrylate, n-decyl-2-cyanoacrylate, isodecyl-2-cyanoacrylate, n-undecyl-2-cyanoacrylate, and n-dodecyl-2-cyanoacrylate. .. These can be used alone or in combination of two or more.

Among these, 2-octyl-2-cyanoacrylate, 2-ethylhexyl-2-cyanoacrylate, n-octyl-2-cyanoacrylate, n-hexyl-2-cyanoacrylate, isobutyl-2-cyanoacrylate and n-butyl It is preferable to contain at least one compound selected from the group consisting of -2-cyanoacrylate because the obtained cured product is excellent in water resistance, cold thermal impact resistance, and heat resistance under high temperature and high humidity conditions. Further, the composition of the present disclosure may contain at least one compound selected from the group consisting of 2-octyl-2-cyanoacrylate and isobutyl-2-cyanoacrylate as the 2-cyanoacrylate compound. preferable.
Further, from the viewpoint of water resistance under high temperature and high humidity conditions, it is also preferable to use 2-octyl-2-cyanoacrylate and isobutyl-2-cyanoacrylate in combination.

The content of alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms is 10% by mass or more, even if it is 10% by mass to 100% by mass, based on the total mass of the 2-cyanoacrylate compound. From the viewpoint of water resistance and cold thermal impact resistance of the obtained cured product under high temperature and high humidity conditions, it is preferably 25% by mass to 100% by mass, and more preferably 40% by mass to 100% by mass. , 50% by mass to 95% by mass is particularly preferable.

It is also preferable that the composition of the present disclosure has the following aspects.
The composition of the present disclosure contains isobutyl-2-cyanoacrylate as a 2-cyanoacrylate compound from the viewpoints of water resistance, cold thermal impact resistance, and heat resistance of the obtained cured product under high temperature and high humidity conditions. However, it is preferably more than 90% by mass and 100% by mass, more preferably 95% by mass to 100% by mass, and particularly preferably 100% by mass with respect to the total mass of the 2-cyanoacrylate compound. ..

<< Alkyl-2-cyanoacrylate having an alkyl group with 1 to 3 carbon atoms >>
In the composition of the present disclosure, an alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms can be blended for the purpose of improving the heat resistance of the obtained cured product.
Various alkyl-2-cyanoacrylates having an alkyl group having 1 to 3 carbon atoms can be blended, and specific examples thereof include methyl-2-cyanoacrylate, ethyl-2-cyanoacrylate, and n-. Examples thereof include propyl-2-cyanoacrylate and isopropyl-2-cyanoacrylate. These can be used alone or in combination of two or more.
Among these, isopropyl-2-cyanoacrylate and / or ethyl-2-cyanoacrylate are preferable, and ethyl-2-cyanoacrylate is more preferable, from the viewpoint of facilitating the enhancement of cold and thermal impact resistance of the obtained cured product.

The content of alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms is based on the total mass of the 2-cyanoacrylate compound from the viewpoint of cold and thermal impact resistance and bending resistance in the obtained cured product. It is preferably 10% by mass or more and 90% by mass or less, more preferably 15% by mass or more and 80% by mass or less, and particularly preferably 20% by mass or more and 60% by mass or less.

<< 2-cyanoacrylate having an ether bond at the ester residue >>
In the composition of the present disclosure, 2-cyanoacrylate having an ether bond at the ester residue can be blended for the purpose of imparting flexibility related to cold and thermal impact resistance in the obtained cured product, and the type thereof includes , Alkoxyalkyl-2-cyanoacrylate, 2-cyanoacrylate of cyclic alkyl ether and the like.
The "ester residue" is an atomic group bonded to an oxygen atom of an ester bond in the compound.
Further, the 2-cyanoacrylate having an ether bond in the ester residue is preferably 2-cyanoacrylate in which the group bonded to the oxygen atom of the ester bond has an ether bond.

Specific examples of alkoxyalkyl-2-cyanoacrylate include methoxyethyl-2-cyanoacrylate, ethoxyethyl-2-cyanoacrylate, propoxyethyl-2-cyanoacrylate, isopropoxyethyl-2-cyanoacrylate, and butoxyethyl-2. -Cyanoacrylate, hexyloxyethyl-2-cyanoacrylate, 2-ethylhexyloxyethyl-2-cyanoacrylate, butoxyethoxyethyl-2-cyanoacrylate, hexyloxyethoxyethyl-2-cyanoacrylate, 2-ethylhexyloxyethoxy Ethyl-2-cyanoacrylate, methoxypropyl-2-cyanoacrylate, methoxypropoxypropyl-2-cyanoacrylate, methoxypropoxypropoxypropyl-2-cyanoacrylate, ethoxypropyl-2-cyanoacrylate and ethoxypropoxypropyl-2-cyanoacrylate And so on.
Specific examples of 2-cyanoacrylate of cyclic alkyl ether include tetrahydrofurfuryl-2-cyanoacrylate.
The 2-cyanoacrylate having an ether bond at the ester residue can be used alone or in combination of two or more.

Among these, it is easy to obtain and excellent in stability by using lower alkoxyethyl-2-cyanoacrylate such as methoxyethyl-2-cyanoacrylate, ethoxyethyl-2-cyanoacrylate and butoxyethyl-2-cyanoacrylate. Therefore, ethoxyethyl-2-cyanoacrylate is preferable, and ethoxyethyl-2-cyanoacrylate is particularly preferable.

When the composition of the present disclosure contains 2-cyanoacrylate having an ether bond in the ester residue, the content of 2-cyanoacrylate having an ether bond in the ester residue determines the water resistance and cold heat resistance in the obtained cured product. From the viewpoint of properties, it is preferably more than 0% by mass and 50% by mass or less, and more preferably more than 0% by mass and 40% by mass or less, based on the total mass of the 2-cyanoacrylate compound.

<Thickener>
The coated wire sealing composition of the present disclosure contains a thickener.
The thickener is not particularly limited as long as it exhibits a thickening effect, but specifically, polymethyl (meth) acrylate, polybutyl (meth) acrylate, methyl methacrylate and methyl acrylate. Copolymers, homopolymers or copolymers of various (meth) acrylates such as copolymers of methyl methacrylate and ethyl acrylate, cellulose derivatives such as hydroxypropyl cellulose and cellulose acetate butyrate, acrylic rubber such as butyl polyacrylate. , Olefin-acrylic rubber such as ethylene-acrylic elastomer, acrylonitrile butadiene rubber (NBR), butadiene rubber (BR) and the like.
Further, the thickener preferably does not have a polar group such as a hydroxy group or an amino group.
Among them, thickeners include olefin-acrylic rubber, acrylonitrile butadiene rubber, and cellulose derivatives from the viewpoints of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. At least one compound selected from the group consisting of acrylic rubber and butadiene rubber is preferable, and at least one compound selected from the group consisting of olefin-acrylic rubber and acrylonitrile butadiene rubber is more preferable, and olefin-. Acrylic rubber is more preferred, and ethylene-acrylic elastomer is particularly preferred.

The weight average molecular weight of the thickener (hereinafter, also referred to as “Mw”) is 10,000 from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. It is preferably 50,000 or more, more preferably 100,000 or more and 1 million or less, and particularly preferably 150,000 or more and 500,000 or less.
In the present disclosure, the weight average molecular weight of the thickener means a value obtained by converting the molecular weight measured by gel permeation chromatography (hereinafter, also referred to as “GPC”) under the following conditions into polystyrene.
Equipment: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: 2 TSKgel GMHXL (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran 1.00 ml / min Detector: RI (Differential Refractometer)

The thickener is a copolymer containing a structural unit derived from a (meth) acrylic monomer from the viewpoint of water resistance, cold thermal impact resistance, and heat resistance of the obtained cured product under high temperature and high humidity conditions. Is preferable.
Examples of the (meth) acrylic monomer include (meth) acrylate compounds, (meth) acrylonitrile, (meth) acrylic acid, and (meth) acrylamide compounds. Specific examples of these are preferably (meth) acrylic monomers used for elastomers described later.
Of these, a monomer unit composed of a (meth) acrylate compound is preferable, and a monomer unit composed of an alkyl (meth) acrylate compound is more preferable.

Further, the thickener is preferably an elastomer from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions.
The "elastomer" in the present disclosure has rubber-like elasticity near room temperature (20 ° C. ± 15 ° C.), or has a peak of tangent (tan δ) of dynamic viscoelasticity measured at a frequency of 1 Hz of 20 ° C. or less. There is no particular limitation as long as it is in.
Examples of elastomers having rubber-like elasticity near room temperature include acrylic acid ester-based copolymers, acrylonitrile-styrene-based copolymers, acrylonitrile-styrene-acrylic acid ester-based copolymers, acrylonitrile-butadiene-based copolymers, and acrylonitrile-. Butadiene-styrene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, ethylene-acrylic acid ester copolymer, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer , Polyurethane-based copolymers, polyester-based copolymers, fluorine-based copolymers, polyisoprene-based copolymers, chloroprene-based copolymers, and the like. These may be used alone or in combination of two or more.
Further, as the elastomer in which the peak of the loss tangent (tan δ) of the dynamic viscoelasticity measured at a frequency of 1 Hz is 20 ° C. or lower, a core-shell type elastomer can also be used.
In the core-shell type elastomer, the glass transition point (hereinafter, also referred to as “Tg”) of the polymer constituting the core and / or shell is preferably 20 ° C. or lower, and more preferably −10 ° C. or lower.
Examples of the monomer of the core phase forming such a polymer include acrylic acid esters, and acrylic acid esters having an alkyl group having 2 to 8 carbon atoms are preferable.
On the other hand, the shell phase forming the outermost layer is not particularly limited as long as it is a polymer component that is easily compatible with or dispersed with the 2-cyanoacrylate compound, but a glassy polymer having a glass transition point of 60 ° C. or higher is used as the outermost layer. It is preferable to form it.
Examples of the monomer forming the glassy polymer include methyl methacrylate and styrene.

Among these elastomers that can be used as thickeners, a monomer in which the homopolymer can be a poorly soluble polymer in the 2-cyanoacrylate compound and a homopolymer in which the homopolymer is soluble in the 2-cyanoacrylate compound are preferable. Examples thereof include copolymers obtained by copolymerizing a monomer (excluding the following monomer having a carboxy group) which can be a polymer of the above. This copolymer can be a poorly soluble segment obtained by polymerizing a monomer in which the homopolymer can be a poorly soluble polymer in the 2-cyanoacrylate compound, and a polymer in which the homopolymer is soluble in the 2-cyanoacrylate compound. It is preferable to include a soluble segment obtained by polymerizing the monomer.

The monomer in which the homopolymer can be a polymer sparingly soluble in the 2-cyanoacrylate compound is not particularly limited, and examples thereof include ethylene, propylene, isoprene, butadiene, chloroprene, 1-hexene and cyclopentene. Only one kind of these monomers may be used, or two or more kinds thereof may be used in combination.
The monomer that can be the poorly soluble polymer is preferably at least one monomer selected from the group consisting of ethylene, propylene, isoprene, butadiene and chloroprene, and is preferably ethylene, propylene, isoprene and butadiene. More preferably, it is at least one monomer selected from the group consisting of.

Further, the monomer in which the homopolymer can be a polymer soluble in the 2-cyanoacrylate compound is not particularly limited, and examples thereof include acrylic acid ester, methacrylic acid ester, vinyl chloride, vinyl acetate, vinyl ether, styrene and acrylonitrile. , At least one monomer selected from the group consisting of acrylic acid ester and methacrylic acid ester is preferable.
Examples of the acrylic acid ester include methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, n-hexyl acrylate, and n-acrylate. Examples thereof include heptyl, n-octyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, methoxypropyl acrylate, ethoxyethyl acrylate and ethoxypropyl acrylate. Only one kind of these monomers may be used, or two or more kinds thereof may be used in combination.
Further, examples of the methacrylic acid ester include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, n-hexyl methacrylate and methacrylic acid. Examples thereof include n-heptyl, n-octyl methacrylate, 2-ethylhexyl methacrylate, methoxyethyl methacrylate, methoxypropyl methacrylate, ethoxyethyl methacrylate and ethoxypropyl methacrylate. Only one kind of these monomers may be used, or two or more kinds thereof may be used in combination.
Further, the acrylic acid ester and the methacrylic acid ester may be used in combination.

The ratio of the sparingly soluble segment obtained by polymerizing the monomer which can be the sparingly soluble polymer and the soluble segment obtained by polymerizing the monomer which can be the soluble polymer is not particularly limited.
When the total of the monomer units forming the sparingly soluble segment and the monomer units forming the soluble segment is 100 mol%, the amount of the monomer unit forming the sparingly soluble segment is preferably 5 mol% to 90 mol%. , More preferably 10 mol% to 80 mol%, further preferably 30 mol% to 80 mol%, particularly preferably 40 mol% to 80 mol%, and most preferably 50 mol% to 75 mol%. Is.
When the total of the monomer units forming the sparingly soluble segment and the monomer units forming the soluble segment is 100 mol%, the amount of the monomer units forming the soluble segment is preferably 10 mol% to 95 mol%, more preferably. Is 20 mol% to 90 mol%, more preferably 20 mol% to 70 mol%, particularly preferably 20 mol% to 60 mol%, and most preferably 25 mol% to 50 mol%.
When the ratio of each segment is in the above range, the copolymer can be appropriately dissolved in the 2-cyanoacrylate compound, and the composition has high shear adhesion strength and excellent durability. can do.
The proportion of each segment can be calculated by the integral value of protons measured by proton nuclear magnetic resonance spectroscopy (hereinafter ^{referred to as "1 H-NMR").}

Further, particularly preferable of the above-mentioned elastomers that can be used as a thickener, a monomer in which the homopolymer can be a poorly soluble polymer in the 2-cyanoacrylate compound and a homopolymer in which the homopolymer is soluble in the 2-cyanoacrylate compound are soluble. There is also a copolymer obtained by copolymerizing a monomer that can be a polymer of the above and a monomer having a carboxy group. In this copolymer, the monomer having a carboxy group may be copolymerized in a small amount.
The monomer having a carboxy group is also not particularly limited, and examples thereof include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, and cinnamic acid. Only one kind of these monomers may be used, or two or more kinds thereof may be used in combination.
Acrylic acid and methacrylic acid are preferably used as the monomer having a carboxy group, and either one of these may be used or may be used in combination.
The segment having a carboxy group obtained by copolymerizing the monomer having a carboxy group becomes a segment soluble in a highly hydrophilic 2-cyanoacrylate compound. When the elastomer is a copolymer having a carboxy group, a composition exhibiting better adhesive durability is provided.

The proportion of segments having a carboxy group is also not particularly limited.
A segment having a carboxy group is formed when the total of the monomer unit forming the sparingly soluble segment, the monomer unit forming the soluble segment, and the monomer unit forming the segment having a carboxy group is 100 mol%. The amount of the monomer unit is preferably 0.1 mol% to 5 mol%, more preferably 0.3 mol% to 4 mol%, still more preferably 0.4 mol% to 3 mol%, and particularly preferably. Is 0.5 mol% to 2.5 mol%, most preferably 0.5 mol% to 2.3 mol%.
When the ratio of the segments having a carboxy group is in the above range, the curable property is excellent and the obtained cured product has excellent temperature resistance.
The proportion of the segment having a carboxy group can be measured by the potentiometric titration method or the indicator titration method according to JIS K0070 (1992).

A monomer in which the homopolymer can be a poorly soluble polymer in a 2-cyanoacrylate compound, and a monomer in which the homopolymer can be a polymer soluble in a 2-cyanoacrylate compound (however, a single amount having the above-mentioned carboxy group). Examples of the copolymer obtained by copolymerizing (excluding the body) include ethylene / methyl acrylate copolymer, ethylene / methyl acrylate / butyl acrylate copolymer, ethylene / methyl methacrylate copolymer, and ethylene. / Vinyl acetate copolymer, butadiene / methyl acrylate copolymer, butadiene / acrylonitrile copolymer, butadiene / acrylonitrile / acrylic acid ester copolymer, butadiene / styrene / acrylonitrile / methyl acrylate copolymer and the like are used. be able to. Of these, ethylene / methyl acrylate copolymer or ethylene / methyl acrylate / butyl acrylate copolymer is particularly preferable.
Further, a copolymer obtained by polymerizing a monomer used for each of the above copolymers and a monomer having a carboxy group such as acrylic acid and / or methacrylic acid, for example, ethylene / acrylic acid. Methyl / methyl acrylate copolymer, ethylene / methyl acrylate / methacrylic acid copolymer, ethylene / methyl acrylate / butyl acrylate / acrylate copolymer, and ethylene / methyl acrylate / butyl acrylate / methacrylic acid A polymer or the like can also be used.
As these copolymers, only one kind may be used, or two or more kinds may be used in combination, and a copolymer in which a monomer having a carboxy group is not copolymerized and a monomer having a carboxy group are used. May be used in combination with a copolymer obtained by copolymerizing the above.

Among them, the thickener is selected from the group consisting of ethylene, propylene, isoprene and butadiene from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. It is preferably a copolymer obtained by at least copolymerizing at least one of the above-mentioned monomers and a (meth) acrylate compound, and at least one selected from the group consisting of ethylene, propylene, isoprene and butadiene. More preferably, it is a copolymer obtained by at least copolymerizing a monomer, a (meth) acrylate compound, and a monomer having a carboxy group.

The thickener may be used alone or in combination of two or more.
The content of the thickener is 100 parts by mass of the 2-cyanoacrylate compound from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions. On the other hand, it is preferably 0.1 part by mass to 30 parts by mass, more preferably 0.5 part by mass to 20 parts by mass, further preferably 1 part by mass to 12 parts by mass, and 2 parts by mass. It is particularly preferable that the amount is 9 parts by mass.

<Pthalic anhydride derivative represented by the formula (1)>
The composition for sealing a coated electric wire of the present disclosure is a phthalic anhydride represented by the following formula (1) from the viewpoints of water resistance, cold thermal impact resistance, and heat resistance of the obtained cured product under high temperature and high humidity conditions. It is preferable to further contain a derivative.

 

In the formula (1), R ¹ independently represents an alkyl group, an acyl group, an acyloxy group, an aryloxycarbonyl group, an aryl group, a hydroxy group, a chlorine atom, a bromine atom or an iodine atom, and n is 1 to 4 Represents an integer of.

^{R 1} in the formula (1) is independently an alkyl group having 1 to 4 carbon atoms, a chlorine atom or a bromine atom from the viewpoint of solubility in a 2-cyanoacrylate compound, stability of the composition and curability. It is preferably a methyl group or a bromine atom.
Further, n is preferably an integer of 1 to 3, more preferably 1 or 2, and particularly preferably 1.

Specific examples of the phthalic anhydride derivative represented by the formula (1) include 3-methylphthalic anhydride, 4-methylphthalic anhydride, 4-tert-butylphthalic anhydride, and 3-hydroxyphthalic anhydride. , 4-Hydroxyphthalic anhydride, 3-acetoxyphthalic anhydride, 4-benzoylphthalic anhydride, 4-phenylphthalic anhydride, 4-phenoxycarbonylphthalic anhydride, 3-chlorophthalic anhydride, 4-Chlorophthalic anhydride, 3-bromophthalic anhydride, 4-bromophthalic anhydride, 3-iodophthalic anhydride, 4-iodophthalic anhydride, 3,4-dichlorophthalic anhydride, 3,5-dichloro Phthrate anhydride, 3,6-dichlorophthalic anhydride, 4,5-dichlorophthalic anhydride, 3,4-dibromophthalic anhydride, 3,5-dibromophthalic anhydride, 3,6-dibromo Phthrate anhydride, 4,5-dibromophthalic anhydride, 3,4-diiodophthalic anhydride, 3,5-diiodophthalic anhydride, 3,6-diiodophthalic anhydride, 4,5-diiodophthalic anhydride , 4-Bromo-5-iodophthalic anhydride, 3,4,5-trichlorophthalic anhydride, 3,4,6-trichlorophthalic anhydride, 3,4,5-tribromophthalic anhydride, 3 , 4,6-Tribromophthalic anhydride, 3,4,5-triiodophthalic anhydride, 3,4,6-triiodophthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride Products, tetraiodophthalic anhydride and the like can be mentioned.

The content of the phthalic anhydride derivative represented by the formula (1) is the total mass of the composition from the viewpoints of water resistance, cold thermal impact resistance, and heat resistance of the obtained cured product under high temperature and high humidity conditions. On the other hand, it is preferably 0.01% by mass to 5% by mass, more preferably 0.05% by mass to 4% by mass, and particularly preferably 0.1% by mass to 3% by mass.

<Plasticizer>
The composition for sealing a coated electric wire of the present disclosure preferably further contains a plasticizer from the viewpoints of water resistance, cold thermal impact resistance, heat resistance, and bending resistance of the obtained cured product under high temperature and high humidity conditions.
As the plasticizer, the thickener is particularly a copolymer composed of a large amount of a monomer that can be a poorly soluble polymer, that is, a copolymer having many poorly soluble segments (for example, the proportion of the poorly soluble segment is high. When 65 mol% or more of the copolymer) is used, the solubility of the copolymer can be improved by containing an appropriate amount.
Plasticizing agents include triethyl acetyl citrate, tributyl acetyl citrate, dimethyl adipate, diethyl adipate, dimethyl sebacate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diisodecyl phthalate, dihexyl phthalate, diheptyl phthalate. , Dioctyl phthalate, bis (2-ethylhexyl) phthalate, diisononyl phthalate, diisotridecyl phthalate, dipentadecyl phthalate, dioctyl terephthalate, diisononyl isophthalate, decyl toruate, bis (2-ethylhexyl) oxalate, 2-ethylhexyl Examples thereof include cyclohexylcarboxylate, diisobutyl fumarate, diisobutyl maleate, triglyceride caproate, 2-ethylhexyl benzoate, and dipropylene glycol dibenzoate.
Among these, tributyl acetylcitrate, dimethyl adipate, dimethyl phthalate, 2-ethylhexyl benzoate, and dipropylene glycol are excellent in compatibility with 2-cyanoacrylate compounds and high plasticization efficiency. It is preferably at least one compound selected from the group consisting of dibenzoate.

Only one type of plasticizer may be used, or two or more types may be used in combination.
The content of the plasticizer is not particularly limited, but the content of the 2-cyanoacrylate compound is contained in the obtained cured product from the viewpoint of water resistance, cold thermal impact resistance, heat resistance, and bending resistance under high temperature and high humidity conditions. The amount is preferably 0.01 parts by mass to 20 parts by mass, more preferably 0.01 parts by mass to 10 parts by mass, and 0.01 parts by mass to 7 parts by mass with respect to 100 parts by mass. Is particularly preferable.

<(Meta) acrylate having two or more (meth) acryloyloxy groups>
The composition of the present disclosure may contain a (meth) acrylate having two or more (meth) acryloyloxy groups for the purpose of imparting heat resistance and flexibility to the obtained cured product. Various (meth) acrylates having two or more (meth) acryloyloxy groups can be used, but from the viewpoint of not easily affecting the stability of the composition and the adhesiveness of the 2-cyanoacrylate compound. , Amino groups and other functional groups are preferred. The upper limit of the number of (meth) acryloyloxy groups is not particularly limited, but may be, for example, 6 or less.

Examples of the (meth) acrylate having two (meth) acryloyloxy groups include ethylene glycol di (meth) acrylate [commercially available products include NK ester 1G (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.). The same applies hereinafter], polyethylene glycol di (meth) acrylate [acrylate: Aronix M-240 (manufactured by Toa Synthetic Co., Ltd.), methacrylate: NK ester 4G, 9G, 14G, 23G (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc. ], Tripropylene glycol di (meth) acrylate [Aronix M-220 (manufactured by Toa Synthetic Co., Ltd.), etc.], Neopentyl glycol di (meth) acrylate [Light acrylate NP-A (manufactured by Kyoeisha Chemical Co., Ltd.), etc.] , 1,6-hexanediol di (meth) acrylate [light acrylate 1.6HX-A (manufactured by Kyoeisha Chemical Co., Ltd.), etc.], ethylene oxide-modified di (meth) acrylate of bisphenol A [Aronix M-211B (Toa Synthetic) Co., Ltd.), etc.], 3- (meth) acryloyloxyglycerin mono (meth) acrylate [light acrylate G-201P (manufactured by Kyoeisha Chemical Co., Ltd.), etc.], hydrogenated dicyclopentadienyldi (meth) acrylate [Light acrylate DCP-A (manufactured by Kyoeisha Chemical Co., Ltd.), etc.], Polyester (meth) acrylate represented by the following formula (A) [KAYARAD HX-220, 620 (manufactured by Nippon Kayaku Co., Ltd.), etc.], Urethane (meth) acrylate [Aronix M-1100, 1200 (manufactured by Toa Synthetic Co., Ltd.), etc.] and bisphenol A-diepoxy- (meth) acrylic acid adduct [Viscort # 540 (manufactured by Osaka Organic Chemical Industry Co., Ltd.) ) Etc.] etc.

 

In the formula (A), the average value of mA + nA is 2 to 4.

Examples of the (meth) acrylate having three (meth) acryloyloxy groups include pentaerythritol tri (meth) acrylate [Aronix M-305 (manufactured by Toa Synthetic Co., Ltd.)], trimethylolpropane tri (meth) acrylate [ Aronix M-309 (manufactured by Toa Synthetic Co., Ltd.), etc.], trimethylolpropane propylene oxide-modified tri (meth) acrylate [Aronix M-321 (manufactured by Toa Synthetic Co., Ltd.), etc.], trimethylolpropane tri (meth) acrylate [NK ester A-TMPT, TMPT (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc.] and the like can be mentioned.
Examples of the (meth) acrylate having four (meth) acryloyloxy groups include pentaerythritol tetra (meth) acrylate [Aronix M-450 (manufactured by Toa Synthetic Co., Ltd.), etc.], and five (meth) acryloyl. As the (meth) acrylate having an oxy group, dipentaerythritol penta (meth) acrylate, and as the (meth) acrylate having 6 (meth) acryloyloxy groups, dipentaerythritol hexa (meth) acrylate [KAYARAD DPHA ( Nippon Kayaku Co., Ltd.)], dipentaerythritol propylene oxide-modified hexa (meth) acrylate [KAYARAD DPCA-20, 30, 60, 1209; Nihon Kayaku Co., Ltd.] and the like can be mentioned.
The (meth) acrylate having two or more (meth) acryloyloxy groups may be used alone or in combination of two or more.

Among these, it is preferable to use an acrylate represented by the formula (1), a polyethylene glycol di (meth) acrylate and / or a polypropylene glycol di (meth) acrylate or the like because the obtained cured product has appropriate flexibility.

The content of the (meth) acrylate having two or more (meth) acryloyloxy groups is 50% by mass or less with respect to the total mass of the composition from the viewpoint of water resistance and cold thermal impact resistance of the obtained cured product. It is preferably 1% by mass to 35% by mass, more preferably 1% by mass to 20% by mass, and particularly preferably 1% by mass to 15% by mass.

<Polymerization initiator>
A polymerization initiator may be added to the composition of the present disclosure.
In particular, in the form of blending the (meth) acrylate component having two or more (meth) acryloyloxy groups in the composition of the present disclosure, the polymerization of the (meth) acrylate component having two or more (meth) acryloyloxy groups. It is preferable to add a radical polymerization initiator that promotes.
Further, as the polymerization initiator, a thermal polymerization initiator is preferably mentioned, and a thermal radical polymerization initiator is more preferably mentioned.
Examples of the radical polymerization initiator include dialkyl peroxides such as hydroperoxide, peroxyester, ketone peroxide, peroxyketal, and di-t-butylhydroperoxide, and diacyl peroxide and peroxydicarbonate. Examples include organic peroxides.
From the viewpoint of storage stability, the content of the polymerization initiator is preferably 0.1% by mass to 1% by mass, preferably 0.3% by mass to 0.6% by mass, based on the total mass of the composition. More preferably.

<Other ingredients>
The composition of the present disclosure may contain other components in addition to the above components. Examples of other components include known additives, and specific examples thereof include stabilizers, polymerization accelerators, dyes, pigments, and diluents.
The content of other components is not particularly limited, but is preferably 20% by mass or less, and more preferably 10% by mass or less, based on the total mass of the composition.

As the other component, a stabilizer is preferably mentioned.
As the stabilizer, known polymerization inhibitors, polymerization inhibitors and the like can be used, and examples thereof include hydroquinone and sulfurous acid gas.

Further, as the other components, a polymerization accelerator is preferably mentioned, and an anionic polymerization accelerator is more preferably mentioned.
Examples of the anionic polymerization accelerator include polyalkylene oxides and derivatives thereof, crown ethers and derivatives thereof, sila crown ethers and derivatives thereof, calixalene derivatives and the like.

In addition to these, dyes, pigments, diluents, fillers (silica particles, etc.) and the like can also be blended.

<How to use>
The composition for sealing a coated electric wire of the present disclosure includes a composition in which one lead wire is coated with an insulating coating, a stranded wire composed of several lead wires is coated with an insulating coating, and the like. It can be used for various coated electric wires.
Specifically, the exposed portion of the coated electric wire and its surroundings are covered with the composition of the present disclosure, and the composition of the present disclosure is cured to seal the exposed portion of the coated electric wire.
Various methods can be adopted as the coating method. For example, a method of applying or injecting the composition of the present disclosure to the exposed portion of the coated electric wire and its periphery, or a method of applying or injecting the composition of the present disclosure to the exposed portion of the coated electric wire and its periphery of the exposed portion of the coated electric wire The method of immersing in the water can be mentioned.
As a method for curing the coated composition of the present disclosure, a method usually adopted for a cyanoacrylate-based adhesive can be applied, and the composition is usually cured by moisture in the air when left unattended, and the curing rate of the composition is high. If it is not sufficient, the coated portion may be coated with an anionic polymerization initiator amine such as N, N'-dimethylaniline, triethanolamine [commercially available products include aa accelerator (manufactured by Toa Synthetic Co., Ltd.)] and the like. Can also be sprayed to accelerate curing.
Among the compositions of the present disclosure, the low-viscosity composition is suitable because it easily penetrates into the gap between the lead wire and the coating, can sufficiently seal the coated electric wire, and has excellent workability. It is preferable to adopt a method of immersing the exposed portion of the electric wire and its surroundings in the composition of the present disclosure.
More specifically, the coated wire of the coated electric wire is crimped with a specific component, and the exposed portion of the coated electric wire and its surroundings are immersed in the composition of the present disclosure. The time for immersing the exposed portion of the covered electric wire and its surroundings may be appropriately selected depending on the type of the composition to be used, but is usually about several seconds to 30 seconds.
In this method, when the curing rate is too fast and the composition does not sufficiently penetrate into the gap between the lead wire and the coating, a composition having an increased proportion of the polymerization inhibitor described above may be used.

(Covered wire)
The coated electric wire of the present disclosure includes a cured product of the composition for sealing the coated electric wire of the present disclosure.
The composition for sealing a coated electric wire of the present disclosure can be suitably used for sealing a portion where the electric wire is exposed at the end of the coated electric wire, particularly the end of the coated electric wire, and two or more coated electric wires can be electrically used. It can be more preferably used to seal the exposed portion of the connected wire.
The exposed electric wire portion may be an end portion or an intermediate portion of the covered electric wire.
Further, the composition for sealing a coated electric wire of the present disclosure may be suitably used for sealing at a connecting portion between a coated electric wire and another member (connector, terminal, protective tool, molding tool, fixture, substrate, etc.). it can.

The electric wire in the coated electric wire is not particularly limited, and a known electric wire can be used. Examples of the material of the electric wire include copper, aluminum, and alloys thereof.
Further, the electric wire may be a single wire or a plurality of strands, but a plurality of strands is preferable.
The coating material in the coated electric wire is not particularly limited, and a known coating material can be used.
The coating material is preferably an insulating material.
Further, the coating material preferably contains a resin, and more preferably contains a thermoplastic resin.
The cross-sectional shape, length, coating thickness, and the like of the coated electric wire are not particularly limited and may be appropriately selected.
As the covered electric wire of the present disclosure, wire harnesses for automobiles, home appliances, OA equipment and the like are preferably mentioned, and wire harnesses for automobiles are particularly preferably mentioned.

Hereinafter, the present invention will be specifically described based on Examples. The present invention is not limited to these examples. In the following, "parts" and "%" mean "parts by mass" and "% by mass", respectively, unless otherwise specified.

<Measurement method of suction length>
The tip of a capillary tube having an inner diameter of 1.05 mm and a length of 120 mm is immersed in a bath solution having a depth of 30 mm for 2 seconds and pulled up, and then the longitudinal direction of the capillary tube is made horizontal with respect to the direction of gravity. The suction length was measured when it was left to stand for 24 hours in a state where it was installed so as to be.
The suction length was measured at 23 ° C. ± 0.5 ° C., and the capillary tube was made of borosilicate glass.

<Method of measuring viscosity at 25 ° C>
The viscosity of the composition was measured under the following conditions using a TVE-20H type viscometer (salt water / flat plate method, manufactured by Toki Sangyo Co., Ltd.), which is an E type viscometer (cone plate type viscometer). ..
-Measurement condition-
Cone shape: Angle 1 ° 34', radius 24 mm
Temperature: 25 ° C ± 0.5 ° C

<Measurement method of storage elastic modulus of cured product of coated electric wire sealing composition at 80 ° C>
The measurement was carried out as follows using MCR 301 manufactured by Antonio Par.
After applying a curing accelerator solution (ethanol solution of 5% by mass N, N'-dimethylparatoluidine) to both sides of the upper and lower parallel plates and drying, apply an appropriate amount of the composition to the lower plate and immediately apply the upper plate. Was lowered. Then, it was left at 25 ° C. for 2 hours, and the storage elastic modulus at 80 ° C. was measured under the conditions of strain 0.1%, frequency 1 Hz, heating rate 2 ° C./min, and initial gap 300 μm.

(Examples 1 to 24 and Comparative Examples 1 to 10)
In Examples 1 to 3, 5 to 11 and 13 to 24, and Comparative Examples 6 to 10, the compounds having the compositions shown in Table 1 were mixed by a conventional method to prepare a coated electric wire sealing composition.
Further, in Examples 4, 12, and Comparative Examples 1 to 5, the compounds having the compositions shown in Table 1 and 1 part by mass of dit-butyl hydroperoxide (perbutyl) with respect to 100 parts by mass of the total amount thereof. Z and NOF Corporation) were mixed by a conventional method to prepare a coated electric wire sealing composition.

<Evaluation>
The obtained coated wire sealing composition was evaluated as follows. The results are shown in Table 2.

-Electric wire sealability test (wet heat test, cold shock test and heat resistance test)-
Peel off the coated polyvinyl chloride of the soft polyvinyl chloride coated wire (diameter of the wire: 2.5 mm in diameter of 30 copper wires, 3.5 mm in outer diameter of the coated PVC) from the tip, and 30 mm from the tip. Was immersed in the coated wire sealing composition for about 2 seconds, and then cured by curing in an atmosphere of 23 ° C. and 50% humidity for 1 day or more.
The wire sealability test was performed on the sealed coated electric wire exposed to a moist heat environment at 80 ° C. and a humidity of 95% RH for 50 hours (wet heat test).
On the other hand, the wire sealability test was also performed on the sealed coated electric wire that was subjected to a cold shock at −40 ° C. for 30 minutes to 120 ° C. for 30 cycles for 100 cycles in the same manner as described above (cold heat shock test).
Further, the sealed electric wire exposed to 120 ° C. for 96 hours was also subjected to an electric wire sealing property test in the same manner as described above (heat resistance test).
In the wire sealability test, compressed air at a predetermined pressure shown below was sent from the unsealed side of the covered wire, and the tip of the covered wire was immersed in water to check for air leakage.
It was evaluated by A to E according to the airtight pressure at which the air leak occurred.
A: Airtight pressure 1.0 kg / cm ² or more B: Airtight pressure 0.8 kg / cm ² or more, less than 1.0 kg / cm ² C: Airtight pressure 0.6 kg / cm ² or more, less than 0.8 kg / cm ^{2 D} : Airtight pressure 0.4 kg / cm ² or more, less than 0.6 kg / cm ² E: Airtight pressure 0.4 kg / cm less than ²

-Bending test (bending resistance test)-
The sealed coated electric wire was measured one by one using the following device based on the description of bending resistance of JIS K5600-5-1 (1999), and visually evaluated according to the following evaluation criteria.
<< Test equipment >>
All Good Cylindrical Mandrel Bending Tester Mandrel Diameter: 2mmΦ
<< Evaluation Criteria >>
A: No cracks and cracks B: No cracks, only cracks C: Both cracks and cracks

 
 

The numerical values in the columns other than the additive (phthalic anhydride derivative represented by the above formula (1)) and the initiator in Table 1 represent the content mass ratio in the composition, and the numerical values in the columns of the additive and the initiator are , Represents the content (ppm) of the composition relative to the total mass. There was no photocurable resin composition whose inside (dark part) was uncured.

The details of the abbreviations in Table 1 are shown below.
KAYARAD HX-620: Acrylate compound represented by the formula (A), mA + nA = 4, KAYARAD HX-220 manufactured by Nippon Kayaku Co., Ltd .: Acrylate compound represented by the formula (A), mA + nA = 2, Japan Chemicals Co., Ltd. M-305: Toagosei Co., Ltd. Aronix M-305 (pentaerythritol tri (meth) acrylate)
Vamac G: ethylene acrylic elastomer (ethylene-methylacrylate-acrylic acid copolymer), manufactured by Du Pont, Mw = 260,000 Vamac LT: ethylene acrylic elastomer (ethylene-methylacrylate-butyl acrylate-acrylic acid copolymer), Du Pont, Mw = 270,000 NIPOL 1072: Acrylic nitrile butadiene rubber, Nippon Zeon Co., Ltd., Mw = 160,000 CAB: Cellulose acetate butyrate, Eastman Chemical Japan, Mw => 70,000 BR-60: Acrylic resin, Mw = 70,000 ATBC: Tributyl acetyl citrate DINP: Diisononyl phthalate DIDP: Diisodecyl phthalate 4-BrPA: 4-Bromophthalic acid anhydride 4-MePA: 4-Methyl phthalate anhydride

As shown in Tables 1 and 2, the coated wire sealing compositions of Examples 1 to 24 have higher water resistance and water resistance under high temperature and high humidity conditions in the obtained cured product than the compositions of Comparative Examples 1 to 10. It has both cold impact resistance and excellent heat resistance of the obtained cured product.
Further, as shown in Tables 1 and 2, the coated wire sealing compositions of Examples 1 to 24 are also excellent in bending resistance of the obtained cured product.

The disclosure of Japanese Patent Application No. 2019-176677, filed September 27, 2019, is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards described herein are to the same extent as if the individual documents, patent applications, and technical standards were specifically and individually stated to be incorporated by reference. Incorporated herein by reference.

The coated electric wire sealing composition of the present disclosure has excellent workability, and the cured product can maintain the electric wire sealing property even under severe high temperature and humidity conditions and cold heat cycle conditions. It can be widely used as an electric wire sealant for wiring of various electric systems such as home appliances and OA equipment.

Claims (18)

1. A 2-cyanoacrylate compound containing 10% by mass or more of an alkyl-2-cyanoacrylate having an alkyl group having 4 or more carbon atoms with respect to the total mass of the 2-cyanoacrylate compound.
   Contains thickeners and
   The viscosity at 25 ° C. is 20 mPa · s to 120 mPa · s.
   Composition for coated electric wire seal.
2. The coated wire sealing composition according to claim 1, wherein the content of the thickener is 1 part by mass to 12 parts by mass with respect to 100 parts by mass of the content of the 2-cyanoacrylate compound.
3. The coated wire sealing composition according to claim 1 or 2, wherein the thickener is a copolymer containing a monomer unit composed of a (meth) acrylic monomer.
4. The composition for a coated electric wire seal according to any one of claims 1 to 3, wherein the thickener is an elastomer.
5. The coated wire sealing composition according to any one of claims 1 to 4, wherein the thickener has a weight average molecular weight of 50,000 or more.
6. The tip of the capillary tube having an inner diameter of 1.05 mm and a length of 120 mm is immersed in a bath solution of the coated electric wire sealing composition having a depth of 30 mm for 2 seconds and pulled up, and then the longitudinal direction of the capillary tube is set in the direction of gravity. The covered electric wire seal according to any one of claims 1 to 5, wherein the suction length when left to stand for 24 hours in a state of being installed in the horizontal direction is 7 mm or more and 35 mm or less. Composition.
7. Any one of claims 1 to 6, wherein the cured product of the coated electric wire sealing composition has a storage elastic modulus of 9.0 × 10 ⁵ Pa or more and 1.5 × 10 ^{8 Pa or less at 80 ° C.} The composition for sealing a coated electric wire according to.
8. The 2-cyanoacrylate compound is 2-octyl-2-cyanoacrylate, 2-ethylhexyl-2-cyanoacrylate, n-octyl-2-cyanoacrylate, n-hexyl-2-cyanoacrylate, n-butyl-2-. The coated wire sealing composition according to any one of claims 1 to 7, which is at least one compound selected from the group consisting of cyanoacrylate and isobutyl-2-cyanoacrylate.
9. Claims 1 to 8 wherein the 2-cyanoacrylate compound contains an alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms and / or a 2-cyanoacrylate having an ether bond at an ester residue. The composition for coating a coated electric wire according to any one of the items.
10. The 2-cyanoacrylate compound contains an alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms.
    Claims 1 to 90, wherein the content of the alkyl-2-cyanoacrylate having an alkyl group having 1 to 3 carbon atoms is 10% by mass or more and 90% by mass or less with respect to the total mass of the 2-cyanoacrylate compound. The composition for sealing a coated electric wire according to any one of claims 9.
11. The 2-cyanoacrylate compound contains 2-cyanoacrylate having an ether bond at the ester residue.
    Any of claims 1 to 10, wherein the content of 2-cyanoacrylate having an ether bond in the ester residue is more than 0% by mass and 50% by mass or less with respect to the total mass of the 2-cyanoacrylate compound. The composition for sealing a coated electric wire according to item 1.
12. Claim 1 The thickener is a copolymer obtained by at least copolymerizing at least one monomer selected from the group consisting of ethylene, propylene, isoprene and butadiene with a (meth) acrylate compound. The composition for sealing a coated electric wire according to any one of claims 11.
13. The thickener comprises at least a copolymerization of at least one monomer selected from the group consisting of ethylene, propylene, isoprene and butadiene, a (meth) acrylate compound and a monomer having a carboxy group. The composition for sealing a coated electric wire according to any one of claims 1 to 12, which is a polymer.
14. The composition for a coated electric wire seal according to any one of claims 1 to 13, further comprising a phthalic anhydride derivative represented by the following formula (1).
    

    

    
    
    In the formula (1), R ¹ independently represents an alkyl group, an acyl group, an acyloxy group, an aryloxycarbonyl group, an aryl group, a hydroxy group, a chlorine atom, a bromine atom or an iodine atom, and n is 1 to 4 Represents an integer of.
15. The composition for a coated electric wire seal according to any one of claims 1 to 14, further comprising a plasticizer.
16. The coated electric wire sealing composition according to claim 15, wherein the content of the plasticizer is 0.01 part by mass to 10 parts by mass with respect to 100 parts by mass of the content of the 2-cyanoacrylate compound.
17. Further containing a (meth) acrylate having two or more (meth) acryloyloxy groups,
    Claims 1 to 35, wherein the content of the (meth) acrylate having two or more (meth) acryloyloxy groups is 1% by mass or more and 35% by mass or less with respect to the total mass of the coated electric wire sealing composition. Item 2. The composition for sealing a coated electric wire according to any one of Items 16.
18. A coated electric wire comprising a cured product of the coated electric wire sealing composition according to any one of claims 1 to 17.