JP2019052258A - Polyvalent hydroxy resin, production method thereof, curing agent for epoxy resin, epoxy resin, epoxy resin composition, cured product thereof, semiconductor encapsulant, and laminate - Google Patents

Abstract

Provided is a polyvalent hydroxy resin capable of obtaining a cured product having a low elastic modulus and excellent heat resistance and adhesion when used as a curing agent for an epoxy resin. A structural unit represented by the formula (1) and a structural unit represented by the formula (2) are included, and the compound represented by the formula (m2) is included or not included. The total content of the structural unit represented by the compound represented by the formula (m2) is 20 to 50% by mass, the content of the compound represented by the formula (m2) is 10% by mass or less, A polyvalent hydroxy resin having a softening point of 50 to 100 ° C. R1 represents a hydrogen atom, a methyl group, a hydroxyl group or an allyl group, q, r, s, t and u each independently represents 0 or 1, n represents an integer of 1 to 15, and R4 represents a carbon number of 10 to 10. 25 represents a linear or branched hydrocarbon group, m and n each independently represents 0 or 1, X represents a hydrogen atom or a hydroxyl group, and Y represents a hydrogen atom or a methyl group. [Chemical 1] [Selected figure] None

Description

  The present invention relates to a polyvalent hydroxy resin, a production method thereof, a curing agent for epoxy resin, an epoxy resin composition, a cured product thereof, an epoxy resin, a semiconductor sealing material, and a laminate.

  In recent years, as represented by smartphones, personal computers, tablets, and the like, electronic devices have become smaller and thinner, and accordingly, the density, integration, and mounting of electronic components are accelerating. In addition, semiconductor devices used therein tend to have a high density due to the narrowing of the wiring pitch, and lead-free high melting point solder is increasing from the environmental aspect. As a method for mounting a semiconductor device, a surface mounting method such as BGA in which a semiconductor element is directly mounted on a circuit board has become mainstream. Among them, phenol resin has strength and heat resistance as an excellent curing agent for epoxy resin, and is widely used for electronic materials.

Printed wiring boards and sealants that are compatible with high-density mounting used in electronic devices tend to be thinner, smaller, and higher in density than before. Has become an issue. In response to this problem, an epoxy resin composition in which a specific phenol resin curing agent is combined with an epoxy resin has been proposed (Patent Document 1).
However, the cured product of the epoxy resin described in Patent Document 1 has a high elastic modulus, is poor in flexibility, and is brittle, so that cracks are likely to occur under severe conditions such as high temperature and high humidity. In addition, the adhesion to other materials such as metals is weak, and wiring peeling is likely to occur when wiring is provided on the surface of the cured product.

In general, a rubber component is effective as a technique for reducing the elastic modulus of a resin material (for example, Patent Document 2).
However, the rubber component has low polarity and is hardly compatible with other resin components. Therefore, in the curing system of the resin composition that is not compatible, there is a concern that uniform curing is difficult and a sea-island structure is formed, and there is a local difference in cured physical properties.

A phenol resin having a long-chain hydrocarbon group has been proposed (for example, Patent Documents 3 to 5). In patent documents 3-5, this phenol resin is made into hardened | cured material with the hardening | curing agent. Hexamethylenetetramine or the like is recommended as the curing agent.
However, gas is generated when the phenol resin is cured using hexamethylenetetramine. In sealing material applications and substrate material applications, it is difficult to use materials that generate gas during curing.

It has been proposed to use a phenol resin having a long-chain hydrocarbon group as a curing agent for an epoxy resin (Patent Document 6).
However, the balance of heat resistance, low elastic modulus, and adhesion of a cured product obtained by curing an epoxy resin using the phenol resin of Patent Document 6 is not sufficient. For example, when the content of long-chain hydrocarbon groups in the resin structure is high, the resulting cured product has a low elastic modulus but low heat resistance.

JP2013-209442A JP2013-256615A JP 2007-2032 A JP 2007-269843 A JP 2013-209439 A Japanese Patent Laying-Open No. 2015-89940

  The present invention has been made in view of the above circumstances, and when used as a curing agent for an epoxy resin, a polyvalent hydroxy resin from which a cured product having a low elastic modulus and excellent heat resistance and adhesion can be obtained, and its An object of the present invention is to provide a production method, and a curing agent for epoxy resins, an epoxy resin, an epoxy resin composition, a cured product thereof, a semiconductor encapsulant, and a laminate using the polyvalent hydroxy resin.

The present invention has the following aspects.
[1] having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2), including or not including a compound represented by the following formula (m2),
The total content of the structural unit represented by the formula (2) and the compound represented by the formula (m2) is 20 to 50% by mass, and the content of the compound represented by the formula (m2) Is a polyvalent hydroxy resin having a softening point of 50 to 100 ° C.

[In the formula, Ar represents a benzene ring or a naphthalene ring, R represents a group represented by the following formula (r1), (r2), (r3), (r4), (r5) or (r6); ¹ represents a hydrogen atom, a methyl group, a hydroxyl group or an allyl group, q, r, s, t and u each independently represents 0 or 1, and at least one of q, r, s, t and u is 1 N represents an integer of 1 to 15,
R ⁴ represents a linear or branched hydrocarbon group having 10 to 25 carbon atoms, m and n each independently represents 0 or 1, X represents a hydrogen atom or a hydroxyl group, and Y represents a hydrogen atom or a methyl group. Indicates. ]

[2] The polyvalent hydroxy resin according to [1], having a mass average molecular weight of 1000 to 5000.
[3] The polyvalent hydroxy resin according to [1] or [2], which has a melt viscosity at 150 ° C. of 0.1 P to 6 P.
[4] A method for producing a polyvalent hydroxy resin according to any one of [1] to [3],
A first step in which a part of at least two phenol components and formaldehyde are reacted in the presence of a basic catalyst to obtain a first reaction product;
A second step of obtaining a polyvalent hydroxy resin by reacting the remainder of the at least two kinds of phenol components and the first reaction product in the presence of an acidic catalyst,
The at least two phenol components include a compound represented by the following formula (m1) and a compound represented by the formula (m2),
The total amount of the compound represented by the formula (m2) is reacted in the first step,
A method for producing a polyvalent hydroxy resin, wherein at least a part of the compound represented by the formula (m1) is reacted in the second step.

[Wherein, Ar, R, R ¹ and n are as defined above,
R ² and R ³ each independently represent a hydrogen atom or a methyl group. ]
[5] The method for producing a polyvalent hydroxy resin according to [4], wherein the content of the binuclear body is 3% by mass or less in the total amount of the compound represented by the formula (m1).
[6] The amount of formaldehyde to be reacted in the first step is 10 to 80% by mass with respect to the compound represented by the formula (m2).
The mass ratio of the compound represented by the formula (m1) to the compound represented by the formula (m2) in the at least two kinds of phenol components is 50:50 to 80:20 [4] or [5] A method for producing a polyvalent hydroxy resin.
[7] A curing agent for epoxy resins, comprising the polyvalent hydroxy resin according to any one of [1] to [3].
[8] An epoxy resin in which at least part of the hydroxyl groups of the polyvalent hydroxy resin according to any one of [1] to [3] is epoxidized.
[9] An epoxy resin composition comprising an epoxy resin and a curing agent for epoxy resin according to [7].
[10] A cured product obtained by curing the epoxy resin composition of [9].
[11] A semiconductor encapsulant comprising the cured product of [10].
[12] A laminate comprising a fibrous base material and a cured product of [10].

  According to the present invention, when used as a curing agent for an epoxy resin, a polyvalent hydroxy resin capable of obtaining a cured product having a low elastic modulus and excellent heat resistance and adhesion, a method for producing the same, and the polyvalent hydroxy resin The used curing agent for epoxy resin, epoxy resin, epoxy resin composition, cured product thereof, semiconductor encapsulant, and laminate can be provided.

<Polyvalent hydroxy resin>
The polyvalent hydroxy resin of the present invention includes a structural unit represented by the following formula (1) (hereinafter also referred to as structural unit (1)) and a structural unit represented by the following formula (2) (hereinafter referred to as structural unit). (Also referred to as (2)). The polyvalent hydroxy resin of the present invention may further have other structural units other than the structural unit (1) and the structural unit (2). “Structural unit” indicates a unit constituting the polymer.

［式中、Ａｒはベンゼン環またはナフタレン環を示し、Ｒは下記式（ｒ１）、（ｒ２）、（ｒ３）、（ｒ４）、（ｒ５）または（ｒ６）で表される基を示し、Ｒ^１は水素原子、メチル基、水酸基またはアリル基を示し、ｑ、ｒ、ｓ、ｔおよびｕはそれぞれ独立に０または１を示し、ｑ、ｒ、ｓ、ｔおよびｕのうち少なくとも１つは１であり、ｎは１〜１５の整数を示し、
Ｒ^４は炭素数１０〜２５の直鎖または分岐状の炭化水素基を示し、ｍおよびｎはそれぞれ独立に０または１を示し、Ｘは水素原子または水酸基を示し、Ｙは水素原子またはメチル基を示す。］

[In the formula, Ar represents a benzene ring or a naphthalene ring, R represents a group represented by the following formula (r1), (r2), (r3), (r4), (r5) or (r6); ¹ represents a hydrogen atom, a methyl group, a hydroxyl group or an allyl group, q, r, s, t and u each independently represents 0 or 1, and at least one of q, r, s, t and u is 1 N represents an integer of 1 to 15,
R ⁴ represents a linear or branched hydrocarbon group having 10 to 25 carbon atoms, m and n each independently represents 0 or 1, X represents a hydrogen atom or a hydroxyl group, and Y represents a hydrogen atom or a methyl group. Indicates. ]

In the above formulas, “-*” represents a bond.
At least one of the six bonds in formula (1) binds to another structural unit (another structural unit (1), structural unit (2), etc.), and three bonds in formula (2). At least one of them binds to another structural unit (another structural unit (2), structural unit (1), etc.). Of the bonds in each formula, bonds not bonded to other structural units are bonded to a hydrogen atom.

  However, Ar in the structural unit (1) and the benzene ring in the structural unit (2) are bonded via a methylene group and are not directly bonded. Further, when two or more structural units (1) are present in the same molecule and the structural units (1) are directly bonded to each other, Ar in each structural unit (1) is bonded through a methylene group, Do not join directly. Similarly, when there are two or more structural units (2) in the same molecule and the structural units (2) are directly bonded to each other, the benzene ring in each structural unit (2) is bonded via a methylene group. And do not join directly.

That is, the bond extending from Ar in Formula (1) is bonded to the methylene group of another structural unit (another structural unit (1), a structural unit (2) in which at least one of m and n is 1), or the like). Or bonded to a hydrogen atom. The bond extending from the methylene group in the formula (1) is bonded to an aromatic ring of another structural unit (a benzene ring of the structural unit (2), Ar of another structural unit (1), or the like) or a hydrogen atom. To join.
The bond extending from the benzene ring in formula (2) is bonded to the methylene group of another structural unit (such as structural unit (1), another structural unit (2) in which at least one of m and n is 1). Or bonded to a hydrogen atom.

When q (or r, s, or t, or u) in the formula (1) is 0, — (CH ₂ ) _q — * (or — (CH ₂ ) _r — *, or — (CH ₂₎ ) _S- * or-(CH ₂ ) _t- * or-(CH ₂ ) _u- *) represents a bond (-*) similar to the bond extending from Ar. That is, it is bonded to a methylene group of another structural unit or bonded to a hydrogen atom.
When q (or r, s, or t, or u) in the formula (1) is 0, — (CH ₂ ) _q — * (or — (CH ₂ ) _r — *, or — (CH ₂₎ ) _S- *, or-(CH ₂ ) _t- *, or-(CH ₂ ) _u- *) represents a bond (-*) similar to the bond extending from the methylene group. That is, it is bonded to an aromatic ring of another structural unit or bonded to a hydrogen atom.
At least one of q, r, s, t and u is 1. That is, at least one bond extending from the methylene group exists. In addition, at least one bond extending from the methylene group is bonded to another structural unit, and — (CH ₂ ) _q — *, — (CH ₂ ) _r — *, — (CH ₂ ) _s — *, — ( CH ₂ ) _t — * and — (CH ₂ ) _u — * are not all bonded to a hydrogen atom.

When m (or n) in Formula (2) is 0, — (CH ₂ ) _m — * (or — (CH ₂ ) _n — *) is a bond similar to the bond extending from the benzene ring ( -*). That is, it is bonded to a methylene group of another structural unit or bonded to a hydrogen atom.
When m (or n) in the formula (2) is 1, — (CH ₂ ) _m — * (or — (CH ₂ ) _n — *) is a methylene group, and the bond is other constituent. Bonded to the aromatic ring of the unit or bonded to a hydrogen atom to form a methyl group. However, when both m and n are 1, at least one of — (CH ₂ ) _m — * and — (CH ₂ ) _n — * is bonded to the benzene ring of another structural unit. That is, two methyl groups are not bonded to the benzene ring in formula (2).

The polyvalent hydroxy resin of the present invention may contain a non-polymer. For example, the raw materials (phenols etc.) used for the production of the polyvalent hydroxy resin may remain.
The polyvalent hydroxy resin of the present invention typically has a compound represented by the following formula (m1) (hereinafter also referred to as compound (m1)) and a compound represented by the following formula (m2) (hereinafter referred to as compound). (M2)) is a reaction product of at least two phenol components including formaldehyde and formaldehyde. That is, it is a polycondensate obtained by polycondensing the at least two phenol components with formaldehyde.
The phenol component may further contain other phenol components other than the compound (m1) and the compound (m2).

［式中、Ａｒ、Ｒ、Ｒ^１、ｎ、Ｒ^４、およびＸはそれぞれ前記と同義であり、
Ｒ^２、Ｒ^３、およびＹはそれぞれ独立に、水素原子またはメチル基を示す。］

[Wherein, Ar, R, R ¹ , n, R ⁴ , and X are as defined above;
R ² , R ³ , and Y each independently represent a hydrogen atom or a methyl group. ]

  The polyvalent hydroxy resin of the present invention may or may not contain the compound (m2). When the polyvalent hydroxy resin contains the compound (m2), the compound (m2) typically remains without reacting during the production of the polyvalent hydroxy resin. In the reaction (polycondensation) of the phenol component with formaldehyde, an unreacted compound (m2) may remain. The compound (m2) has a high boiling point and cannot be removed by distillation, and tends to remain in the polyvalent hydroxy resin.

(Structural unit (1))
The structural unit (1) contributes to the improvement of the heat resistance of the cured product.
In the above formula (1), (n + 1) R ^{1 s} may be the same or different. The same applies to q, r, s, and t. When n is 2 or more, n pieces of R may be the same or different from each other. The average value of n is preferably 1 to 20, and more preferably 1 to 15.
R is preferably a group represented by the above formula (r1) from the viewpoint of availability of raw materials and cost.

The structural unit (1) is derived from the compound (m1).
As the compound (m1), bisphenol A, bisphenol F, a reaction product of a monovalent or divalent phenol component represented by the following formula (i) and a crosslinking agent (hereinafter also referred to as a phenol resin (I)). Etc. In the case of the phenol resin (I), R in the formula (m1) is a crosslinking group derived from a crosslinking agent.

［式中、Ｒ^１〜Ｒ^３はそれぞれ前記と同義である。］

[Wherein, R ^{1 to} R ³ are as defined above. ]

Monovalent phenol components (compounds in which R ¹ in formula (i) is a hydrogen atom, a methyl group, or an allyl group) include phenol, orthocresol, paracresol, metacresol, allylphenol, ethylphenol, propylphenol Octylphenol, nonylphenol, 1-naphthol, 2-naphthol and the like.
Examples of the divalent phenol component (a compound in which R ¹ in formula (i) is a hydroxyl group) include hydroquinone, resorcin, catechol, naphthalenediols, and the like.
Cross-linking agents include formaldehyde, acetaldehyde, benzaldehyde, parahydroxybenzaldehyde, paraxylylene glycol, paraxylylene glycol dimethyl ether, divinylbenzene, diisopropenylbenzene, dimethoxymethylbiphenyls, divinylbiphenyl, diisopropenylbiphenyls, bischloro Examples include methyl biphenyl and paraxylylene dichloride.

Specific examples of the phenol resin (I) include phenol novolak, orthocresol novolak, allylphenol novolak, naphthol novolak, dicyclopentadiene type phenol resin, phenol aralkyl resin, biphenyl aralkyl type phenol resin, naphthol aralkyl resin, triphenylmethane type. Phenol novolac and the like can be mentioned.
As the phenol resin (I), a commercially available product may be used, or a product produced by a known production method may be used. The phenol resin (I) can be produced by reacting a monovalent or divalent phenol component with a crosslinking agent. The said reaction can be implemented by a conventional method.

200-5000 are preferable and, as for the mass mean molecular weight (Mw) of phenol resin (I), 300-4000 are more preferable. When Mw is not less than the above lower limit, the resulting resin has a low viscosity, and the resulting cured product is excellent in low elastic modulus, and when it is not more than the above upper limit, the resulting cured product is excellent in heat resistance.
Mw is a value measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

Of the total amount of the compound (m1) used in the production of the polyvalent hydroxy resin, the content of the binuclear body is preferably 3% by mass or less, and more preferably 2% by mass or less. The lower limit is not particularly limited, and may be 0% by mass. If the content of the binuclear body is less than or equal to the above upper limit, the content of the polynuclear body having 4 or more nuclei in the polyvalent hydroxy resin is sufficiently increased, and the heat resistance of the cured product is further improved.
A binuclear body is a compound having two aromatic rings. Examples of the binuclear compound include compounds in which n in the formula (m1) is 1, and R is a group represented by the formula (r1), (r2), or (r6).

(Structural unit (2))
The structural unit (2) is a structural unit derived from the compound (m2), and contributes to lowering the elastic modulus and improving the adhesion of the cured product.
In formula (2), R ⁴ is a linear or branched hydrocarbon group having 10 to 25 carbon atoms. When the number of carbon atoms is 10 or more, it is easy to lower the melt viscosity of the polyvalent hydroxy resin, and it is easy to obtain a cured product having a low elastic modulus and high adhesion. When the number of carbon atoms is 25 or less, the heat resistance of the cured product is excellent.
10-25 are preferable and, as for carbon number of the said hydrocarbon group, 15-20 are more preferable.
The hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group having an unsaturated bond (carbon-carbon double bond, carbon-carbon triple bond, etc.). The number of unsaturated bonds contained in the unsaturated hydrocarbon group may be one or two or more.
Specific examples of the hydrocarbon group include — (CH ₂ ) ₁₄ CH ₃ , — (CH ₂ ) ₇ CH═CH (CH ₂ ) ₅ CH ₃ , — (CH ₂ ) ₇ CH═CHCH ₂ CH═CH ( _{CH 2) 2 CH 3, -} (CH 2) 7 CH = CHCH 2 CH = CHCH = CHCH 3, - (CH 2) 7 CH = CHCH 2 CH = CHCH 2 CH = CH 2 and the like.
In formula (2), X is preferably a hydrogen atom in terms of low water absorption of the cured product.

In the formula (2), the bonding position of R ^{4 in} the benzene ring is preferably the meta position (the 3rd position or the 5th position) with respect to the position where the hydroxyl group is bonded (the 1st position) in terms of reactivity with formaldehyde. When X is a hydroxyl group, the 1-position indicates not the X bonding position but the hydroxyl bonding position shown as “OH” in the formula.
The bonding position of X in the benzene ring is not particularly limited. When X is a hydroxyl group, from the viewpoint of reactivity with formaldehyde, the meta position is preferred with respect to the position (the 1st position) where the hydroxyl group is represented as “OH” in the formula.
In the structural unit (2), the bonding position of the methylene group in the benzene ring is not particularly limited. Typically, it is either the ortho position (2nd or 6th position) or the para position (4th position) with respect to the position where the hydroxyl group is bonded (1st position).

The structural unit (2) is derived from the compound (m2).
In the compound (m2), the bonding position of Y in the benzene ring is not particularly limited. When Y is a methyl group, the ortho position is preferred with respect to the position to which the hydroxyl group is bonded (position 1).
The compound (m2) used in the production of the polyvalent hydroxy resin may consist of a single compound or a mixture of two or more thereof. For example, cashew nut shell liquid and purified product thereof, cardanol, cardol (also called curdle). ), 2-methylcardol, anacardic acid, urushiol and the like.

As the compound (m2), cashew nuts are relatively inexpensive, easy to control the reactivity, and the obtained polyvalent hydroxy resin tends to exhibit low viscosity characteristics and easily obtain a cured product having a low elastic modulus. Shell liquid or a purified product thereof is preferred. Cashew nut shell liquid and purified products thereof often contain a plurality of compounds (m2) containing cardanol.
The cashew nut shell liquid or a purified product thereof has a cardanol content of 70 to 100% by mass, a cardol content of 0 to 25% by mass, and a methyl cardanol with respect to the total mass of the cashew nut shell liquid or the purified product thereof. Is preferably 0 to 5%, and the total amount of cardanol, cardol, and methylcardanol (active ingredient amount) is 70% by mass or more.

(Other phenol components)
Examples of the other structural unit include structural units derived from other phenol components other than the compound (m1) and the compound (m2).
Examples of other phenol components include phenol, orthocresol, paracresol, metacresol, allylphenol, ethylphenol, propylphenol, octylphenol, nonylphenol, and the like. The other phenol component used in the reaction may be a single compound or a mixture of two or more.
Among the above, since it is inexpensive, excellent in reactivity, and has a low boiling point, it can be easily removed, and can be easily recycled even when used in large quantities. Therefore, phenol, orthocresol, paracresol, and allylphenol are preferable.

In the polyvalent hydroxy resin of the present invention, the total content of the structural unit (2) and the compound (m2) is 20 to 50% by mass and 30 to 40% by mass with respect to the total mass of the polyvalent hydroxy resin. Is preferred. The structural unit (2) and the compound (m2) both have R ⁴ . If the total content of the structural unit (2) and the compound (m2) is not less than the above lower limit value, a sufficient amount of R ⁴ is present, and the cured product can have a low elastic modulus and high adhesion. If total content of a structural unit (2) and a compound (m2) is below the said upper limit, the curability at the time of hardening an epoxy resin and the heat resistance of hardened | cured material will be excellent.

  In the polyvalent hydroxy resin of the present invention, the content of the compound (m2) is 10% by mass or less, preferably 5% by mass or less, based on the total mass of the polyvalent hydroxy resin. The lower limit is not particularly limited, and may be 0% by mass. If content of a compound (m2) is below the said upper limit, the heat resistance of cured | curing material will be excellent.

  In the polyvalent hydroxy resin of the present invention, the content of the structural unit (1) is preferably 50 to 80% by mass and more preferably 60 to 70% by mass with respect to the total mass of the polyvalent hydroxy resin. If content of a structural unit (1) is more than the said lower limit, the heat resistance of cured | curing material will be more excellent. If content of a structural unit (1) is below the said upper limit, hardened | cured material can be made into a low elasticity modulus and high adhesiveness more.

  In the polyvalent hydroxy resin of the present invention, the content of other structural units is preferably 0 to 30% by mass and more preferably 0 to 20% by mass with respect to the total mass of the polyvalent hydroxy resin.

  The polyvalent hydroxy resin of the present invention preferably contains no unreacted phenol component and formaldehyde other than the compound (m2) from the viewpoints of the environment and the curing rate with the epoxy resin.

The softening point of the polyvalent hydroxy resin of the present invention is 50 to 100 ° C, preferably 60 to 90 ° C. When the softening point is equal to or higher than the lower limit, the fluidity when the polyvalent hydroxy resin is melted is excellent, and the inorganic filler can be highly blended. Moreover, it is excellent in the heat resistance and low elastic modulus of the hardened | cured material obtained. If a softening point is below the said upper limit, it is excellent in a moldability and the heat resistance of hardened | cured material.
The softening point of the polyvalent hydroxy resin is measured according to JIS K 6910.
The softening point of the polyvalent hydroxy resin can be adjusted by the mass ratio between the compound (m1) and the compound (m2), the reaction conditions, and the like.

The melt viscosity at 150 ° C. of the polyvalent hydroxy resin of the present invention is preferably 0.1P to 6P, and more preferably 0.2P to 4P. When the melt viscosity is at least the above lower limit, the fluidity at the time of melting of the polyvalent hydroxy resin is excellent, and high blending of the inorganic filler becomes possible. When the melt viscosity is not more than the above upper limit, the fluidity is excellent.
The melt viscosity of the polyvalent hydroxy resin is measured by a method based on JIS K 7117-2.
The melt viscosity of the polyvalent hydroxy resin can be adjusted by the mass average molecular weight (Mw) of the polyvalent hydroxy resin, the total content of the structural unit (2) and the compound (m2).

1000-5000 are preferable and, as for the mass mean molecular weight (Mw) of the polyvalent hydroxy resin of this invention, 1500-4500 are more preferable. When the Mw is not less than the above lower limit, the reactivity with the epoxy resin is excellent, and the heat resistance of the cured product is more excellent. When Mw is not more than the above upper limit, the fluidity at the time of melting of the polyvalent hydroxy resin is more excellent.
The dispersity (Mw / number average molecular weight (Mn)) of the polyvalent hydroxy resin is preferably 1.5 to 4.5, more preferably 2.0 to 4.0.
Mw and Mn are values measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

The hydroxyl equivalent of the polyvalent hydroxy resin of the present invention is preferably 110 to 160 g / eq, more preferably 115 to 150 g / eq. When the hydroxyl equivalent is not less than the above lower limit, the heat resistance of the cured product is more excellent. When the hydroxyl group equivalent is not more than the above upper limit, the cured product has a lower elastic modulus.
The hydroxyl group equivalent of the polyvalent hydroxy resin is measured by an acetylation method using acetic anhydride.

<Method for producing polyvalent hydroxy resin>
The polyvalent hydroxy resin of the present invention can be produced by reacting at least two phenol components including the compound (m1) and the compound (m2) with formaldehyde.
When the phenol component and formaldehyde are reacted, an addition reaction (methylolation reaction) of formaldehyde with respect to the phenol component and a condensation reaction between the produced methylol body and the phenol component proceed. Thereby, a polyvalent hydroxy resin is produced.

  In the at least two phenol compounds, the mass ratio of the compound (m1): the compound (m2) is preferably 50:50 to 80:20. When the mass ratio of the compound (m1): the compound (m2) is within the above range, the total content of the structural unit (2) and the compound (m2) in the polyvalent hydroxy resin is in the range of 20 to 50% by mass. It is easy to be inside.

  In the above-mentioned at least two kinds of phenol compounds, the mass ratio of the total mass of other phenol components: compound (m1) and compound (m2) is preferably 0: 100 to 60:40, and 0: 100 to 50:50. More preferred.

As a manufacturing method of the polyvalent hydroxy resin of this invention, the following manufacturing methods are preferable.
A first step in which a part of the at least two phenol components and formaldehyde are reacted in the presence of a basic catalyst to obtain a first reaction product;
A second step of obtaining a polyvalent hydroxy resin by reacting the remainder of the at least two kinds of phenol components and the first reaction product in the presence of an acidic catalyst,
The total amount of compound (m2) is reacted in the first step,
A method for producing a polyvalent hydroxy resin, wherein at least a part of the compound (m1) is reacted in the second step.

Of the compound (m1) and the compound (m2), the compound (m2) is less reactive with formaldehyde. Therefore, when these are reacted with formaldehyde all at once, the unreacted compound (m2) tends to remain in the reaction product. When the compound (m2) remains in the polyvalent hydroxy resin, the cured physical properties are deteriorated. Further, since the compound (m2) has a high boiling point, the remaining compound (m2) cannot be easily removed.
Therefore, first, the whole amount of the compound (m2) is reacted with formaldehyde, and then at least a part of the compound (m1) is reacted. A part of the compound (m1) may be reacted with the compound (m2) in the first step.
When the compound (m2) and formaldehyde are reacted in the presence of a basic catalyst, 1 to 3 molecules of formaldehyde are added to the compound (m2) to form a methylol compound represented by the following formula (3). By adding the compound (m1) to the methylol body thus produced, it is possible to suppress the compound (m2) from remaining in the polyvalent hydroxy resin.

［式中、Ｒ^４、ＸおよびＹはそれぞれ前記と同義であり、ｋは１〜３の整数を示す。］

[Wherein, R ⁴ , X and Y are as defined above, and k represents an integer of 1 to 3. ]

The reaction between the methylol body and the compound (m1) proceeds even in the presence of the basic catalyst, but in the presence of the basic catalyst, the methylol bodies react with each other to form a polymer that does not contain the structural unit (1). The side reaction such as the reaction of generating a methylol body is more likely to occur due to the reaction to form and the formaldehyde generated by the reaction of the methylol body.
On the other hand, in the presence of an acidic catalyst, the reaction between the methylol produced in the first stage reaction and the compound (m1) in excess tends to preferentially proceed, and the formaldehyde produced by the reaction of the methylol is excessive. It reacts preferentially with the compound (m1) in the above, and the side reaction as described above hardly occurs.

  In the above production method, when another phenol component is reacted as a phenol component, the other phenol component may be reacted in the first step, may be reacted in the second step, or reacted in both steps. Also good. The timing for reacting the other phenol components can be appropriately set according to the reactivity with formaldehyde. For example, allylphenol, like compound (m1), is more reactive with formaldehyde than compound (m2), so it is preferable to react in the second step.

  Hereinafter, the first step and the second step will be described in detail.

(First step)
In the first step, a part of the above-mentioned at least two phenol components and formaldehyde are reacted in the presence of a basic catalyst to obtain a first reaction product.
The phenol component to be reacted in the first step includes the total amount of the compound (m2). As needed, a part of compound (m1) and a part or all of other phenol components may be contained.
When the proportion of the compound (m1) in the phenol component to be reacted in the first step and other phenol components increases, the amount of the polymer not having the structural unit (2) increases, or the compound (m2) remaining unreacted. If the amount increases, the cured physical properties may decrease. Therefore, from the viewpoint of obtaining more excellent cured properties, the compound (m1) to be reacted in the first step is preferably 20% by mass or less with respect to the compound (m2). Moreover, 20 mass% or less of the other phenol component made to react at a 1st process is preferable with respect to a compound (m2). The lower limit of the ratio of the compound (m1) and the other phenol component to the compound (m2) is not particularly limited, and may be 0% by mass.

  Formaldehyde may be a solid or an aqueous solution. It is preferable to use an aqueous solution because it is inexpensive and the reaction can be easily controlled.

10-80 mass% is preferable with respect to a compound (m2), and, as for the quantity of the formaldehyde made to react at a 1st process, 20-60 mass% is more preferable.
0.5-4.0 are preferable and, as for the molar ratio (formaldehyde / compound (m2)) of formaldehyde and a compound (m2), 1.0-3.0 are more preferable.
As the amount of formaldehyde is smaller within the above range, the total content of the structural unit (2) and the compound (m2) in the polyvalent hydroxy resin tends to increase. As the amount of formaldehyde is larger within the above range, the ratio of the compound (m2) to the total content tends to decrease.
If the amount of formaldehyde is too small, a large amount of unreacted compound (m2) remains in the produced polyvalent hydroxy resin, and the cured physical properties such as glass transition temperature and curing rate may be lowered. If the amount of formaldehyde is too large, excess formaldehyde remains in the produced polyvalent hydroxy resin, and it is necessary to remove the formaldehyde.
The cashew nut shell liquid may contain components other than the compound (m2). When cashew nut shell liquid is used, the amount of the active ingredient (total amount of cardanol, cardol, and methyl cardanol) of cashew nut shell liquid is the amount of compound (m2).

  The basic catalyst is not particularly limited as long as the reaction proceeds. For example, alkali metal hydroxides (sodium hydroxide, potassium hydroxide, etc.), ammonia water, tertiary amines (triethylamine, etc.), alkaline earth metal oxides and hydroxides such as calcium, magnesium, barium, sodium carbonate, sodium carbonate And alkaline substances such as A basic catalyst may be used individually by 1 type, or may use 2 or more types together.

In the first step, the amount of the basic catalyst used is preferably 1.3 to 40% by mass and more preferably 6.7 to 20% by mass with respect to the compound (m2).
0.1-3.0 are preferable and, as for the molar ratio (basic catalyst / compound (m2)) of a basic catalyst and a compound (m2), 0.5-1.5 are more preferable.
If the amount of the basic catalyst used is too small, the reaction rate is slow, and if the amount used is too large, the reaction proceeds rapidly and it becomes difficult to control the reaction.

The first step is preferably performed in the presence of an alcohol having 1 to 4 carbon atoms such as methanol, ethanol, propanol, butanol and the like. Thereby, it can prevent that a compound (m2) and a reaction product aggregate during reaction.
C1-C4 alcohol may be used individually by 1 type, or may use 2 or more types together. As the alcohol having 1 to 4 carbon atoms, methanol is particularly preferable.
As for the usage-amount of C1-C4 alcohol, 10-100 mass% is preferable with respect to a compound (m2).
In the subsequent reaction with the compound (m1) under an acidic catalyst (second step), the alcohol having 1 to 4 carbon atoms remaining in the reaction system also functions as an alkylating agent. The methylol group (—CH ₂ OH) of the compound (m2) methylolated in the first step (methylol form of the above formula (3)) is an alkyl group of an alcohol having 1 to 4 carbon atoms (hereinafter abbreviated as R ⁵ ). .) To be —CH ₂ O—R ⁵ (capped methylol body). Thereby, compared with the case where a methylol group exists as it is, the side reaction which a methylol body of a compound (m2) reacts in the case of reaction of a 2nd process does not arise easily.
On the other hand, since the methylol body and the capped methylol body easily react with the compound (m1) present in excess, the desired resin is easily obtained.

0-100 degreeC is preferable and, as for the reaction temperature in a 1st process, 30-60 degreeC is more preferable. If the reaction temperature is too low, the reaction does not proceed. If the reaction temperature is too high, it becomes difficult to control the reaction, and it becomes difficult to stably obtain the target polyvalent hydroxy resin.
At the end of the reaction in the first step, an acid may be added to the reaction system to neutralize the basic catalyst.

(Second step)
In the second step, the remainder of the above-described at least two phenol components (the phenol component not reacted in the first step) and the first reaction product obtained in the first step are present in the presence of an acidic catalyst. React.
The phenol component to be reacted in the second step includes a part or all of the compound (m1). If necessary, some or all of the other phenol components may be contained.

The acidic catalyst is not particularly limited as long as the reaction proceeds. Examples include hydrochloric acid, sulfuric acid, phosphoric acid, oxalic acid, trifluoroacetic acid, p-toluenesulfonic acid, methanesulfonic acid, boron trifluoride, aluminum chloride, iron chloride, zinc chloride and the like. An acidic catalyst may be used individually by 1 type, or may use 2 or more types together.
Of the above, phosphoric acid and oxalic acid are preferred. These acidic catalysts are available at a relatively low cost. Further, when R ⁴ contains an unsaturated bond, the polymerization reaction of the unsaturated bond hardly occurs when the raw material or the reaction product contains an unsaturated bond.

In the second step, the amount of the acidic catalyst used is preferably 0.04 to 12.6% by mass, more preferably 0.4 to 4.2% by mass, based on the compound (m2) used in the first step.
The molar ratio of the acidic catalyst to the compound (m2) (acidic catalyst / compound (m2)) is preferably 0.001 to 0.3, and more preferably 0.01 to 0.1.
If the amount of the acidic catalyst used is too small, the reaction rate is slow, and if the amount used is too large, the reaction proceeds rapidly and it becomes difficult to control the reaction.

  30-150 degreeC is preferable and, as for the reaction temperature in a 2nd process, 80-120 degreeC is more preferable. If the reaction temperature is too low, the reaction does not proceed. If the reaction temperature is too high, it becomes difficult to control the reaction, and it becomes difficult to stably obtain the target polyvalent hydroxy resin.

The reaction product obtained in the second step can be directly used as the polyvalent hydroxy resin of the present invention.
After the reaction in the second step, if necessary, the reaction product may be subjected to treatment such as removal of unreacted raw materials by distillation or the like, concentration, purification (washing, column chromatography, etc.), etc. . Unreacted formaldehyde is preferably removed by washing or distillation. When other phenol components are used, it is preferable to remove other phenol components.

  The polyvalent hydroxy resin of the present invention has the structural unit (1) and the structural unit (2), and the total content of the structural unit (2) and the compound (m2) is 20 to 50% by mass. Since the content of the compound (m2) is 10% by mass or less and the softening point is 50 to 100 ° C., when used as a curing agent for epoxy resins, it has low elasticity and heat resistance and adhesion. An excellent cured product can be obtained. In addition, it is possible to obtain effects such as a high curing speed with the epoxy resin, an uncured portion hardly generated at the time of curing, and excellent toughness of the cured product.

Conventionally, a general method for synthesizing a polyvalent hydroxy resin having a long-chain hydrocarbon group includes a method in which the compound (m2), other phenols, aldehydes and the like are collectively reacted in the presence of a catalyst. In the polyvalent hydroxy resin obtained by such a production method, the compound (m2) as the monomer component tends to remain. Moreover, since the compound (m2) has a high boiling point, it is difficult to remove.
When the epoxy resin is cured using a polyvalent hydroxy resin, a phenolic hydroxyl group (hydroxyl group bonded to an aromatic ring) reacts unlike the case where the polyvalent hydroxy resin is cured with hexamethylenetetramine. When the compound (m2) remains in the polyvalent hydroxy resin, the phenolic hydroxyl group of the compound (m2) also reacts at the time of curing, thereby inhibiting the molecular weight growth. The remaining of the compound (m2) not only adversely affects the environment, but also causes a decrease in the curing rate and uncuring of the epoxy resin, and there is a concern that the physical properties and reliability of the cured product will be significantly decreased. When the remaining compound (m2) is further reacted and consumed, the molecular weight increases, and the fluidity decreases. Moreover, although hardened | cured material becomes low elasticity and high adhesiveness, Tg becomes low and heat resistance falls.
In the polyvalent hydroxy resin of the present invention, since the content of the compound (m2) is 10% by mass or less, the molecular weight growth is difficult to be inhibited at the time of curing, and the curing rate of the epoxy resin is reduced, uncured, Deterioration of physical properties is difficult to occur. Since the total content of the structural unit (2) and the compound (m2) is 20% by mass or more, the cured product is formed by the long-chain hydrocarbon group (R ⁴ ) derived from the structural unit (2) or the compound (m2). Low elasticity and high adhesion. The high adhesion is considered to be due to the anchor effect of the long-chain hydrocarbon group on the other material. On the other hand, if the long-chain hydrocarbon group is present in excess, Tg is lowered and heat resistance is lowered. Since the total content is 50% by mass or less, the cured product has high heat resistance.

The use of the polyvalent hydroxy resin of the present invention is not particularly limited, and can be used for various known uses as the use of a polyvalent hydroxy resin such as a phenol resin.
For example, since the polyvalent hydroxy resin of the present invention has a plurality of hydroxyl groups, it serves as a curing agent (crosslinking agent) for compounds having functional groups (epoxy groups, carboxyl groups, isocyanate groups, halides, etc.) that react with hydroxyl groups. Can be used. Since the said effect is show | played, the polyvalent hydroxy resin of this invention is suitable as a hardening | curing agent for epoxy resins.
The polyvalent hydroxy resin of the present invention can be used as a material for producing an epoxy resin. For example, an epoxy resin can be obtained by epoxidizing the hydroxyl group of a polyvalent hydroxy resin.

<Curing agent for epoxy resin>
The epoxy resin curing agent of the present invention comprises the above-described polyvalent hydroxy resin of the present invention. That is, the preferable aspect of the curing agent for epoxy resins of the present invention is the same as the preferable aspect of the polyvalent hydroxy resin of the present invention.

<Epoxy resin>
The epoxy resin of the present invention is obtained by epoxidizing at least part of the hydroxyl groups of the polyvalent hydroxy resin of the present invention.
Epoxidation of the hydroxyl group can be carried out by a known method. For example, by reacting a polyvalent hydroxy resin with epichlorohydrin, part or all of the hydroxyl groups (phenolic hydroxyl groups in the structural unit (1), structural unit (2), etc.) of the polyvalent hydroxy resin are —OZ. (Here, Z is a glycidyl group.) An epoxy resin having a structure can be obtained.

<Epoxy resin composition>
The epoxy resin composition of the present invention includes an epoxy resin and the aforementioned curing agent for epoxy resin of the present invention.
The epoxy resin composition of this invention may further contain other components other than the epoxy resin and the hardening | curing agent for epoxy resins of this invention as needed.
The epoxy resin composition of the present invention may contain a solvent, if necessary.
A solvent can be blended in the epoxy resin composition of the present invention, and a resin varnish can be obtained by dissolving an epoxy resin, an epoxy resin curing agent, and the like in the solvent. Such a resin varnish is useful as a laminate material used in the production of laminates.
When using the epoxy resin composition of the present invention as a sealing material (semiconductor sealing material or the like), the epoxy resin composition of the present invention preferably does not contain a solvent.

The epoxy resin is not particularly limited, and may be a known epoxy resin, such as a phenol novolac type epoxy resin, an orthocresol novolac type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a biphenol type epoxy resin, Naphthalene type epoxy resin, anthracene type epoxy resin, naphthol type epoxy resin, xylylene type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin, stilbene type epoxy resin, sulfur atom-containing epoxy resin, A phosphorus atom containing epoxy resin etc. are mentioned. Any one of these epoxy resins may be used alone, or two or more thereof may be used in combination.
As the epoxy resin, the epoxy resin of the present invention (an epoxy resin in which at least a part of the hydroxyl groups of the polyvalent hydroxy resin of the present invention is epoxidized) may be used.

  In the epoxy resin composition, since the content of the curing agent for epoxy resin of the present invention has good cured product properties, the epoxy equivalent of epoxy resin / the hydroxyl equivalent of the curing agent for epoxy resin of the present invention is 0.7. The amount is preferably 1.5, and more preferably 0.9 to 1.1 because the cured product is more excellent in heat resistance, low elastic modulus, and adhesion.

As other components, a curing agent other than the epoxy resin curing agent of the present invention (hereinafter also referred to as other curing agent), a curing accelerator, a filler (filler), a release agent, a surface treatment agent, a colorant. And a flexibility imparting agent.
As other curing agents, those conventionally known as curing agents used for epoxy resins can be used, such as phenol resins such as phenol novolac resins and triphenylmethane type phenol resins, acid anhydrides, amine resins and the like. It is done.

It does not specifically limit as a hardening accelerator, A well-known hardening accelerator may be sufficient. Examples thereof include phosphorus compounds, tertiary amines, imidazole compounds, organic acid metal salts, Lewis acids, amine complex salts, and the like. Examples of the phosphorus compound include triphenylphosphine, tris-2,6-dimethoxyphenylphosphine, tri-p-tolylphosphine, and triphenyl phosphite. Examples of the tertiary amine include 2-dimethylaminomethylphenol, benzyldimethylamine, α-methylbenzyldimethylamine, 1,8-diazabicyclo [5.4.0] undecene-7, and the like. Examples of the imidazole compound include 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, and the like. Any one of these curing accelerators may be used alone, or two or more thereof may be used in combination.
As the curing accelerator, a phosphorus compound (particularly triphenylphosphine) and an imidazole compound are preferable in that they are more excellent in curability, heat resistance, and electrical properties, and are difficult to reduce moisture reliability.
As for content of a hardening accelerator, 0.1-5 mass% is preferable with respect to an epoxy resin.

Examples of the filler (filler) include crystalline silica powder, fusible silica powder, quartz glass powder, talc, calcium silicate powder, zirconium silicate powder, alumina powder, calcium carbonate powder, and the like. A fusible silica powder is preferred.
Examples of the release agent include various waxes such as carnauba wax.
Examples of the surface treatment agent include known silane coupling agents.
Examples of the colorant include carbon black.
Examples of the flexibility imparting agent include silicone resin and butadiene-acrylonitrile rubber.

  The solvent is not particularly limited as long as it can dissolve an epoxy resin, a curing agent, a curing accelerator, and the like, and a polar solvent is typically used. Examples of polar solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, N, N-dimethylformamide, N-methyl-2-pyrrolidone, methanol, ethanol, butanol, ethyl acetate, butyl acetate, methyl cellosolve, ethyl diglycol acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, tetrahydrofuran and the like.

  The epoxy resin composition of this invention can be prepared by mixing an epoxy resin, the hardening | curing agent for epoxy resins of this invention, and another component as needed. Mixing can be performed by a conventional method.

The epoxy resin composition of the present invention has thermosetting properties and can be used as a thermosetting molding material.
There is no restriction | limiting in particular as an application of the epoxy resin composition of this invention, It may be the same as that of the use of a well-known thermosetting molding material. For example, a sealing material, a film material, a laminated material, etc. are mentioned.

<Hardened product>
The cured product of the present invention is obtained by curing the epoxy resin composition of the present invention.
Curing of the epoxy resin composition is preferably performed by controlling the temperature at 100 to 200 ° C.
As an example of the curing operation, there may be mentioned a method of once performing curing at the above-mentioned suitable temperature for 30 seconds to 1 hour and further performing post-curing at the above-mentioned suitable temperature for 1 to 20 hours.

<Semiconductor encapsulant>
The semiconductor sealing material of the present invention includes the cured product of the present invention.
The shape of the sealing material is not particularly limited, and a shape similar to the shape of the sealing material employed in a known semiconductor or the like can be employed.
The method for forming the sealing material of the present invention is not particularly limited, and a known molding method such as a transfer forming method or a compression forming method can be employed.

<Laminated plate>
The laminated board of this invention contains a fibrous base material and the hardened | cured material of this invention.

Examples of fibers constituting the fibrous base material include inorganic fibers such as glass fibers, carbon fibers, ceramic fibers, and stainless fibers; natural fibers such as cotton, hemp, and paper; synthetic organic fibers such as polyester resins and polyamide resins. Can be mentioned. Any one of these fibers may be used alone, or two or more thereof may be used in combination.
The shape of the fibrous base material is not particularly limited, and examples thereof include short fibers, yarns, mats, and sheets.

  The laminated board of this invention can be manufactured using the resin varnish containing an epoxy resin, the hardening | curing agent for epoxy resins of this invention, and a solvent. For example, a laminate comprising a prepreg in which a fibrous base material is impregnated with a resin varnish is heated and pressurized and cured to obtain a laminate.

The resin varnish is the same as the above-described epoxy resin composition of the present invention except that a solvent is an essential component.
The content of the solvent in the resin varnish is appropriately set according to the solid content concentration of the resin varnish. The solid content concentration of the resin varnish varies depending on the use, but is preferably 30 to 80% by mass, and more preferably 50 to 70% by mass.
The solid content concentration of the resin varnish is the ratio of the mass of the resin varnish excluding the solvent to the total mass of the resin varnish.

The prepreg is obtained by impregnating a fibrous base material with a resin varnish, drying, and removing the solvent.
The amount of the resin varnish to be impregnated into the fibrous base material is not particularly limited. For example, the solid content of the resin varnish to be impregnated is about 30 to 50% by mass with respect to the fibrous base material (100% by mass). To be.

The number of prepregs laminated in the laminate may be one layer or two or more layers.
In the laminate, a substrate other than the prepreg may be laminated. As another base material, metal foil, such as copper foil, is mentioned, for example.
The heating temperature for heating and pressurizing the laminate is preferably the aforementioned curing temperature. As a pressurizing condition, ² to ²⁰ kN / m ² is preferable.

  The laminated board manufactured as mentioned above is provided with the fiber reinforced resin layer containing a fibrous base material and the hardened | cured material of a resin varnish. The number of fiber reinforced resin layers provided in the laminate may be one or two or more. The laminated board may have metal foil layers, such as copper foil.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the examples.
In the following, “%” indicates “mass%” unless otherwise specified.
The measuring method of the characteristic of polyvalent hydroxy resin and the raw material used for manufacture of polyvalent hydroxy resin are shown below.

<Measurement method>
[Mass average molecular weight (Mw), dispersity (Mw / Mn)]
The mass average molecular weight (Mw) and dispersity (Mw / Mn) of the polyvalent hydroxy resin were measured using the following GPC apparatus and column as a standard substance as polystyrene.
GPC apparatus: HLC8120GPC manufactured by Tosoh Corporation.
Column: TSKgel G3000H + G2000H + G2000H.

[Hydroxyl equivalent]
The hydroxyl group equivalent of the polyvalent hydroxy resin was measured by an acetylation method with acetic anhydride using an automatic titrator (COM-1700S manufactured by Hiranuma Sangyo).

[Melt viscosity]
The melt viscosity of the polyvalent hydroxy resin was measured by a viscometer (CAP2000 VISCOMETER manufactured by Brookfield) set at 150 ° C.

[Softening point]
The softening point of the polyvalent hydroxy resin was measured according to JIS K 6910.

<Raw materials>
Cashew nut shell liquid (CNSL): GOLDEN CASHEW PRODUCTS PVT Co., Ltd., trade name: CARDANOL, component: cardanol content 90.44%, cardol content 4.02%, methyl cardol 1.04%, total of them (Amount of active ingredient) 95.5%.
LVR8210DL: phenol novolak, manufactured by Gunei Chemical Industry Co., Ltd., trade name: LVR8210DL, softening point 69 ° C., 150 ° C. melt viscosity 0.5 P, mass average molecular weight (Mw) 508, binuclear content 0.8%.
PS-4271: phenol novolak, manufactured by Gunei Chemical Industry Co., Ltd., trade name: PS-4271, softening point 70 ° C., 150 ° C. melt viscosity 0.7 P, mass average molecular weight (Mw) 800, binuclear content 27 %.
The softening point, melt viscosity, and Mw of these phenol novolacs were measured by the same measurement method as described above. The binuclear content was measured by GPC area%.
Incidentally, the phenol novolaks, ^R 1 to R ³ in the formula (m1) is a hydrogen atom, R consists of one or more of the compounds represented by formula (r1). According to GPC, the main component of LVR8210DL was a compound having n = 2 (about 80 area%), and the main component of PS-4271 was a compound having n = 1 (about 27 area%). The main component means a structure having the highest structure ratio in the GPC distribution.

<Example 1>
A 3 L glass flask equipped with a thermometer, stirrer, and condenser is charged with 300 g of CNSL, 150 g of methanol, and 180 g of a 50% formaldehyde aqueous solution (3.0 mol, 60% with respect to CNSL). 133 g of an aqueous sodium hydroxide solution was added dropwise at 35 ° C. over 1.5 hours. Thereafter, methylolation reaction of CNSL was performed at 60 ° C. for 4 hours. Next, 1200 g of methyl isobutyl ketone was added, neutralized with 220 g of 30% acetic acid, washed with water, neutralized salts were removed, 1200 g of LVR8210DL (CNSL: LVR8210DL = 20: 80), and oxalic acid 6 g was added to acidify the system, and an addition reaction was performed at 100 ° C. for 4 hours. Subsequently, washing with water was performed, and then methyl isobutyl ketone was distilled off to obtain a polyvalent hydroxy resin A.
The softening point of the polyvalent hydroxy resin A is 78 ° C., the melt viscosity at 150 ° C. is 1.5 P, the mass average molecular weight (Mw) in gel permeation chromatography (GPC) is 2260, and the dispersity (Mw / Mn) is 2. 980, the hydroxyl group equivalent was 116 g / eq. The total content of the structural unit (2) and the compound (m2) is 20.0% (the balance is 80.0%) with respect to the total mass of the polyvalent hydroxy resin A, and the content of the compound (m2) Was 0.13%. These contents were determined by the mass of the polyvalent hydroxy resin A, the amount of CNSL used, and gas chromatography.

<Example 2>
A 3 L glass flask equipped with a thermometer, stirrer, and condenser is charged with 300 g of CNSL, 150 g of methanol, and 135 g of a 50% aqueous formaldehyde solution (2.25 mol, 45% relative to CNSL), and 30% of the mixture 133 g of an aqueous sodium hydroxide solution was added dropwise at 35 ° C. over 1.5 hours. Thereafter, methylolation reaction of CNSL was performed at 60 ° C. for 4 hours. Next, 450 g of methyl isobutyl ketone was added, neutralized with 220 g of 30% acetic acid, washed with water, neutralized salts were removed, 700 g of LVR8210DL (CNSL: LVR8210DL = 30: 70), and oxalic acid 7.5 g was added to acidify the system, and an addition reaction was performed at 100 ° C. for 4 hours. Next, washing with water was performed, and then methyl isobutyl ketone was distilled off to obtain a polyvalent hydroxy resin B.
The softening point of the polyvalent hydroxy resin B is 78 ° C., the melt viscosity at 150 ° C. is 3.2 P, the mass average molecular weight (Mw) in gel permeation chromatography (GPC) is 2941, and the degree of dispersion (Mw / Mn) is 2. 977, and the hydroxyl equivalent weight was 125 g / eq. The total content of the structural unit (2) and the compound (m2) is 30.0% (the balance is 70.0%) with respect to the total mass of the polyvalent hydroxy resin B, and the content of the compound (m2) Was 0.05%. These contents were determined by the mass of the polyvalent hydroxy resin B, the amount of CNSL used, and gas chromatography.

<Example 3>
A 3 L glass flask equipped with a thermometer, stirrer, and condenser is charged with 300 g of CNSL, 150 g of methanol, and 135 g of a 50% aqueous formaldehyde solution (2.25 mol, 45% relative to CNSL), and 30% of the mixture 133 g of an aqueous sodium hydroxide solution was added dropwise at 35 ° C. over 1.5 hours. Thereafter, methylolation reaction of CNSL was performed at 60 ° C. for 4 hours. Next, 450 g of methyl isobutyl ketone was added, neutralized with 220 g of 30% acetic acid, washed with water, neutralized salts were removed, and 700 g of PS-4271 (CNSL: PS-4271 = 30: 70) Then, 7.5 g of oxalic acid was added to acidify the system, and an addition reaction was performed at 100 ° C. for 4 hours. Next, washing with water was performed, and then methyl isobutyl ketone was distilled off to obtain a polyvalent hydroxy resin C.
The softening point of the polyvalent hydroxy resin C is 83 ° C., the melt viscosity at 150 ° C. is 4.1 P, the mass average molecular weight (Mw) in gel permeation chromatography (GPC) is 3819, and the dispersity (Mw / Mn) is 3. 566 and the hydroxyl equivalent weight was 125 g / eq. The total content of the structural unit (2) and the compound (m2) is 30.0% (the balance is 70.0%) with respect to the total mass of the polyvalent hydroxy resin C, and the content of the compound (m2) Was 0.16%. These contents were determined by the mass of the polyvalent hydroxy resin C, the amount of CNSL used, and gas chromatography.

<Example 4>
A 3 L glass flask equipped with a thermometer, stirrer, and condenser is charged with 300 g of CNSL, 150 g of methanol, and 120 g of 50% formaldehyde aqueous solution (2.0 mol, 40% based on CNSL), and 30% of the mixture 133 g of an aqueous sodium hydroxide solution was added dropwise at 35 ° C. over 1.5 hours. Thereafter, CNSL methylolation reaction was carried out at 35 ° C. for 6 hours. Next, 450 g of methyl isobutyl ketone was added, neutralized with 220 g of 30% acetic acid, washed with water, the neutralized salt was removed, 450 g of LVR8210DL (CNSL: LVR8210DL = 40: 60), and oxalic acid 7.5 g was added to acidify the system, and an addition reaction was performed at 100 ° C. for 4 hours. Next, washing with water was performed, and then methyl isobutyl ketone was distilled off to obtain a polyvalent hydroxy resin D.
The softening point of the polyvalent hydroxy resin D is 60 ° C., the melt viscosity at 125 ° C. is 3.0 P, the melt viscosity at 150 ° C. is 0.2 P, and the mass average molecular weight (Mw) in gel permeation chromatography (GPC) is 1880, The dispersity (Mw / Mn) was 2.148, and the hydroxyl equivalent was 140 g / eq. The total content of the structural unit (2) and the compound (m2) is 40.0% (the balance is 60.0%) with respect to the total mass of the polyvalent hydroxy resin D, and the content of the compound (m2) Was 3.6%. These contents were determined by the mass of the polyvalent hydroxy resin D, the amount of CNSL used, and gas chromatography.

<Example 5>
A 3 L glass flask equipped with a thermometer, stirrer, and condenser is charged with 300 g of CNSL, 150 g of methanol, and 120 g of 50% formaldehyde aqueous solution (2.0 mol, 40% based on CNSL), and 30% of the mixture 133 g of an aqueous sodium hydroxide solution was added dropwise at 35 ° C. over 1.5 hours. Thereafter, methylolation reaction of CNSL was performed at 60 ° C. for 4 hours. Next, 450 g of methyl isobutyl ketone was added, neutralized with 220 g of 30% acetic acid, washed with water, the neutralized salt was removed, 450 g of LVR8210DL (CNSL: LVR8210DL = 40: 60), and oxalic acid 7.5 g was added to acidify the system, and an addition reaction was performed at 100 ° C. for 4 hours. Next, washing with water was performed, and then methyl isobutyl ketone was distilled off to obtain a polyvalent hydroxy resin E.
The softening point of the polyvalent hydroxy resin E is 79 ° C., the melt viscosity at 150 ° C. is 3.7 P, the mass average molecular weight (Mw) in gel permeation chromatography (GPC) is 4293, and the dispersity (Mw / Mn) is 3. 522, hydroxyl equivalent was 148 g / eq. The total content of the structural unit (2) and the compound (m2) is 40.0% (the balance is 60.0%) with respect to the total mass of the polyvalent hydroxy resin E, and the content of the compound (m2) Was 0.23%. These contents were determined by the mass of the polyvalent hydroxy resin E, the amount of CNSL used, and gas chromatography.

<Comparative Example 1>
Phenol novolac resin (manufactured by Gunei Chemical Industry Co., Ltd., trade name: PS-4261, softening point 82 ° C., 150 ° C. melt viscosity 2.2 P, hydroxyl group equivalent 104 g / eq) was designated as polyvalent hydroxy resin F.

<Comparative example 2>
Phenol novolac resin (manufactured by Gunei Chemical Industry Co., Ltd., trade name: PS-4271, softening point 70 ° C., 150 ° C. melt viscosity 0.7 P, hydroxyl group equivalent 104 g / eq) was designated as polyvalent hydroxy resin G.

  Table 1 summarizes the characteristics of the polyvalent hydroxy resins A to G.

<Evaluation>
A curing agent, an epoxy resin and a curing accelerator were mixed in the composition shown in Table 2 to obtain an epoxy resin composition. The compounding amounts of the epoxy resin and the curing agent were set so that the equivalent ratio of the epoxy group equivalent in the epoxy resin and the hydroxyl group equivalent in the curing agent was 1.
In Table 2, the curing agents A to G are the polyvalent hydroxy resins A to G, respectively.
The epoxy resin is an ortho-cresol type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., product name: EOCN1020).
The curing accelerator is triphenylphosphine (reagent: manufactured by Wako Pure Chemical Industries, Ltd.).
The following evaluation was performed about the obtained epoxy resin composition. The results are shown in Table 2.

[Production of molded product (cured product)]
The obtained epoxy resin composition was melted at 110 ° C., poured into a mold of width 100 mm × length 100 mm × thickness 1 mm, press-molded at 180 ° C., and afterbaked at 180 ° C. for 5 hours, width 100 mm × length A molded product (cured product) having a thickness of 100 mm and a thickness of 1 mm was obtained.

[Glass transition temperature and storage modulus of cured product]
The produced molded product was processed into a width of 10.0 mm, a length of 5.5 mm, and a thickness of 1.0 mm to obtain a test piece. About the said test piece, viscoelasticity measurement is carried out in the range of 30 degreeC-300 degreeC with the temperature increase rate of 2 degree-C / min using a viscoelasticity measuring apparatus (Hitachi High-Tech Science make, DMA7100), and glass transition temperature (Tg). And the storage modulus at 120 ° C. was determined.

[5% heat reduction temperature of cured product]
The produced molded product is finely pulverized and heated in a range of 30 ° C. to 600 ° C. at a temperature increase rate of 10 ° C./min in an air atmosphere by a differential thermothermal gravimetric simultaneous measurement apparatus (TG / DTA6300 manufactured by Seiko Instruments Inc.). The weight loss was measured and the 5% heat reduction temperature was determined.

[Bending strength, flexural modulus]
The produced molded product was processed into a test piece by processing the width 25.0 mm × length 30.0 mm × thickness 1.0 mm. About the said test piece, the bending strength and bending elastic modulus in 25 degreeC were measured according to JISK6911: 1955 using the Toyo Seiki Co., Ltd. tension compression testing machine (Strograph V10-C).

[Shear strength]
Two oxygen-free copper plates C1020P (width 10 mm × length 50 mm × thickness 1 mm) were prepared.
The obtained epoxy resin composition was melted at 110 ° C., applied on one side of one oxygen-free copper plate C1020P, and the other oxygen-free copper plate C1020P was stacked thereon, so that the adhesion surface by the epoxy resin composition was approximately 10 mm × Adhesion was made to be 10 mm. Thereafter, the epoxy resin composition was cured at 180 ° C. for 5 hours to obtain a test piece in which a pair of oxygen-free copper plates C1020P were laminated via a layer made of a cured product of the epoxy resin composition.
The above test piece was subjected to a tensile test using a tensile compression tester (Strograph V10-C) manufactured by Toyo Seiki Co., Ltd. at room temperature, a distance between chucks of 70 mm, and a shear rate of 5 mm / min. The shear strength (N / mm ² ) was calculated from the load (N) and the test piece adhesion area (mm ² ).

The cured product of the epoxy resin composition using the polyvalent hydroxy resin of Examples 1 to 5 had a sufficiently high glass transition temperature and 5% thermal decomposition temperature, and was excellent in heat resistance. Further, the storage elastic modulus at 120 ° C. and the bending elastic modulus at 25 ° C. were low and the elastic modulus was low. Moreover, the shear strength was high and the adhesiveness was excellent. Further, the bending strength at 25 ° C. was sufficiently high and the toughness was excellent.
The hardened | cured material of the epoxy resin composition using the polyvalent hydroxy resin of Comparative Examples 1-2 was high in elasticity, and was inferior to adhesiveness.

  By using the polyvalent hydroxy resin of the present invention as a curing agent for epoxy resins, it is possible to impart a low elastic modulus, high heat resistance and high adhesion to the cured product. Therefore, the polyvalent hydroxy resin of the present invention and the epoxy resin composition using the same are extremely useful as a high-functional polymer material. It can be used for a wide range of applications such as electrical insulating materials, resins for copper-clad laminates, resins for conductive pastes, resins for sealing electronic parts, paints, various coating agents, adhesives, and build-up laminate materials.

Claims (12)

Having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2), including or not including a compound represented by the following formula (m2),
The total content of the structural unit represented by the formula (2) and the compound represented by the formula (m2) is 20 to 50% by mass, and the content of the compound represented by the formula (m2) Is a polyvalent hydroxy resin having a softening point of 50 to 100 ° C.

[In the formula, Ar represents a benzene ring or a naphthalene ring, R represents a group represented by the following formula (r1), (r2), (r3), (r4), (r5) or (r6); ¹ represents a hydrogen atom, a methyl group, a hydroxyl group or an allyl group, q, r, s, t and u each independently represents 0 or 1, and at least one of q, r, s, t and u is 1 N represents an integer of 1 to 15,
R ⁴ represents a linear or branched hydrocarbon group having 10 to 25 carbon atoms, m and n each independently represents 0 or 1, X represents a hydrogen atom or a hydroxyl group, and Y represents a hydrogen atom or a methyl group. Indicates. ]

  The polyvalent hydroxy resin according to claim 1, which has a mass average molecular weight of 1,000 to 5,000.   The polyvalent hydroxy resin according to claim 1 or 2, wherein the melt viscosity at 150 ° C is 0.1P to 6P. A method for producing a polyvalent hydroxy resin according to any one of claims 1 to 3,
A first step in which a part of at least two phenol components and formaldehyde are reacted in the presence of a basic catalyst to obtain a first reaction product;
A second step of obtaining a polyvalent hydroxy resin by reacting the remainder of the at least two kinds of phenol components and the first reaction product in the presence of an acidic catalyst,
The at least two phenol components include a compound represented by the following formula (m1) and a compound represented by the formula (m2),
The total amount of the compound represented by the formula (m2) is reacted in the first step,
A method for producing a polyvalent hydroxy resin, wherein at least a part of the compound represented by the formula (m1) is reacted in the second step.

[Wherein, Ar, R, R ¹ and n are as defined above,
R ² and R ³ each independently represent a hydrogen atom or a methyl group. ]   The method for producing a polyvalent hydroxy resin according to claim 4, wherein the content of the binuclear body is 3% by mass or less in the total amount of the compound represented by the formula (m1). The amount of formaldehyde reacted in the first step is 10 to 80% by mass with respect to the compound represented by the formula (m2),
The mass ratio of the compound represented by the formula (m1) to the compound represented by the formula (m2) in the at least two kinds of phenol components is 50:50 to 80:20. A method for producing a polyvalent hydroxy resin.   The hardening | curing agent for epoxy resins which consists of a polyhydric hydroxy resin as described in any one of Claims 1-3.   The epoxy resin in which at least one part of the hydroxyl group of the polyhydric hydroxy resin as described in any one of Claims 1-3 was epoxidized.   The epoxy resin composition containing an epoxy resin and the hardening | curing agent for epoxy resins of Claim 7.   A cured product obtained by curing the epoxy resin composition according to claim 9.   The semiconductor sealing material containing the hardened | cured material of Claim 10.   A laminate comprising a fibrous base material and the cured product according to claim 10.