JPWO2015152037A1 - Phenol resin, epoxy resin composition containing the phenol resin, cured product of the epoxy resin composition, and semiconductor device having the cured product - Google Patents

Abstract

A phenol resin represented by the general formula (1), wherein the cured product obtained from the phenol resin, the epoxy resin represented by the general formula (2), and a curing accelerator is 40 ° C or higher and 180 ° C or lower. , A coefficient of thermal expansion of 1.5% or more is given. It is preferable that the phenol resin gives the cured product a storage elastic modulus of 15 MPa or more at 250 ° C.

Description

  The present invention relates to a phenolic resin. The present invention also relates to an epoxy resin composition containing the phenol resin and a cured product of the epoxy resin composition. Furthermore, this invention relates to the semiconductor device which has this hardened | cured material.

  Epoxy resin compositions are widely used in the fields of electric / electronic parts, structural materials, adhesives, paints and the like due to workability and excellent electrical properties, heat resistance, adhesion, moisture resistance, etc. of the cured product.

  In recent years, with the increase in performance, size, and thickness of electronic devices typified by smartphones and tablet terminals, the number of pins, high integration, size, and thickness of semiconductor devices are accelerating. For this reason, in a single-side sealed package such as a conventional BGA (Ball Grid Array) package, an improvement in reliability due to a reduction in warp accompanying thinning is required.

  In a single-sided sealed package, internal stress remains due to the difference in thermal expansion coefficient between the substrate material and the member used in the semiconductor device, such as a sealing resin, resulting in warpage and mounting reliability. There is a problem that it decreases. In conventional single-sided sealed packages, the thermal expansion coefficient of the sealing resin is larger than that of a substrate material including a base material such as glass cloth, and warping occurs on the sealing resin side, so that the thermal expansion coefficient of the sealing resin is reduced. Has been studied.

  However, in recent single-side sealed packages, the thickness has been reduced, and the number of packages with a thin sealing resin layer is increasing. As a result, unlike the conventional single-side sealed package, there is a problem that warpage occurs on the substrate material side due to the shrinkage of the substrate material. Therefore, there is a demand for reducing warpage to the substrate material side at room temperature by increasing the thermal shrinkage of the sealing resin after molding.

  As a technique for reducing the warp by increasing the thermal shrinkage of the sealing resin, the thermal shrinkage ratio is improved by reducing the amount of the inorganic filler in the sealing resin (Patent Document 1), or the silicon compound is directly bonded to silicon. There has been proposed a method for improving the thermal contraction rate (Patent Document 2) of a sealing resin by using a silicone compound containing a silanol group without containing an alkoxy group.

  In addition, as the thickness of the sealing resin becomes thinner, there is a demand for improved reliability by imparting rigidity to the sealing resin when heated. Therefore, there is a demand for a material having high thermal rigidity, that is, a high thermal elastic modulus.

JP-A-8-153831 JP 2013-224400 A

  However, if the amount of the inorganic filler is reduced as in the technique described in Patent Document 1, there is a concern about deterioration of moisture resistance reliability due to deterioration of the water absorption rate of the cured product. Moreover, even if it uses the silicone compound containing the silanol group of patent document 2, it does not lead to the improvement of the elasticity modulus of hardened | cured material. As described above, the technology that has been proposed so far focuses on the additive in the epoxy resin composition, and no proposal has been made for improvement of the resin itself. Therefore, it is desired to develop a phenol resin that has a large thermal expansion when a cured product of the epoxy resin composition is heated, in other words, a large thermal contraction during cooling and a high elastic modulus during heating.

  Accordingly, an object of the present invention is to provide a phenolic resin that can provide an epoxy resin composition having high heat shrinkage and high elastic modulus that can realize improvement in reliability by reducing warpage of a thinned single-side sealed package. It is to provide.

  As a result of intensive investigations to solve the above problems, the present inventors have found that a cured product having a large degree of thermal expansion due to heating has a high thermal shrinkage rate upon cooling, and further studies based on this finding. As a result of the progress, by using a phenol resin comprising a phenol compound having a saturated or unsaturated hydrocarbon group having 2 to 15 carbon atoms, an epoxy resin having a large degree of thermal expansion due to heating and a high thermal shrinkage rate upon cooling. It was found that a composition and a cured product were obtained, and the present invention was completed.

前記フェノール樹脂は、該フェノール樹脂と、下記一般式（２）

で表されるエポキシ樹脂と、硬化促進剤とから得られる硬化物に、４０℃以上１８０℃以下において、１．５％以上の熱膨張率を与えるものであるフェノール樹脂を提供することにより、前記の課題を解決するものである。That is, the present invention is a phenol resin represented by the following general formula (1),

The phenol resin includes the phenol resin and the following general formula (2).

By providing a phenol resin that gives a coefficient of thermal expansion of 1.5% or more at 40 ° C. or more and 180 ° C. or less to a cured product obtained from the epoxy resin represented by It solves the problem.

  Moreover, this invention provides the epoxy resin composition containing the said phenol resin and an epoxy resin, and the epoxy resin hardened | cured material formed by hardening | curing this epoxy resin composition.

  The semiconductor device of a thin single-sided sealed package having a sealing material formed from an epoxy resin composition using the phenolic resin of the present invention, due to the high coefficient of thermal expansion during heating of the sealing material, The thermal contraction rate at the time of cooling is also high, whereby warpage generated in the substrate material on which the semiconductor device is mounted can be reduced.

  The phenol resin of the present invention is represented by the general formula (1). In the formula (1), the saturated or unsaturated hydrocarbon group represented by R has a large rotational free volume around the phenylene axis, so that it exhibits high thermal expansion during heating, and consequently high thermal shrinkage during cooling. From the viewpoint of expression of sex. From this viewpoint, the carbon number of R is 2 or more and 15 or less as described above, preferably 3 or more and 15 or less, more preferably 3 or more and 10 or less, and most preferably 3 or 4.

  In the formula (1), when R is a saturated hydrocarbon group, examples of the group include an ethyl group, an n-butyl group, a tert-butyl group, a propyl group, and an octyl group. In particular, it is preferable to use a tert-butyl group which is a group having a large rotational free volume around the phenylene axis. On the other hand, when R is an unsaturated hydrocarbon group, examples of the group include an allyl group, a 1-propenyl group, and an acetylene group. In particular, when an allyl group that is a group having a large rotational free volume around the phenylene axis is used, the thermal expansion coefficient of the cured product of the epoxy resin composition can be increased, and the thermal elastic modulus can be increased. preferable. R may be the same or different. Preferably all R are the same group. In that case, the group is preferably an allyl group.

  In formula (1), q represents an integer of 1 or more and 3 or less as described above, and is preferably 1 or 2. In order to increase the thermal elastic modulus of the cured epoxy resin, a larger q value is preferable. In formula (1), p is preferably either 1 or 2. When p and q are both 1, R is preferably bonded to the o-position or p-position with respect to OH.

  In formula (1), n represents an integer of 0 or more as described above. The upper limit of n is preferably a value such that the melt viscosity at 150 ° C. of the phenol resin of the present invention is 30.0 P or less, more preferably 0.1 P or more and less than 20.0 P, and still more preferably 0.8. The value is preferably 1 P or more and 10.0 P or less, more preferably 0.1 P or more and 7.0 P or less, and most preferably 0.1 P or more and 5.0 P or less. Since the phenol resin of the present invention is an aggregate of polymers having various molecular weights, the value of n is represented by an average value in the aggregate.

  The phenol resin of the present invention preferably has a melt viscosity at 150 ° C. in the above range from the viewpoint of successfully producing a semiconductor sealing material obtained by kneading with an inorganic filler or the like. In addition, the softening point is 100 ° C. or less, particularly 50 ° C. or more and 100 ° C. or less, particularly 60 ° C. or more and 90 ° C. or less, particularly 60 ° C. or more and 80 ° C. or less from a temperature lower than 25 ° C. (ie, liquid state at 25 ° C.). It is preferable from the viewpoint of handling in handling due to blocking or the like, and handling in a kneading operation with an inorganic filler or the like. Moreover, it is preferable also from the point which can raise the elastic modulus at the time of the epoxy resin hardened | cured material obtained from the phenol resin of this invention. Further, the hydroxyl group equivalent is 400 g / eq or less, particularly 300 g / eq or less, particularly 200 g / eq or less, and it is effectively prevented that the crosslinking density of the cured epoxy resin is excessively low, and the elasticity at the time of heating. It is preferable from the point which can suppress the fall of a rate effectively. Although there is no restriction | limiting in particular in the lower limit of a hydroxyl equivalent, If it is 100 g / eq or more, a satisfactory result will be obtained. The measuring method of these physical property values will be described in the examples described later.

  The phenol resin of the present invention is a cured product obtained from the epoxy resin represented by the above general formula (2) and a curing accelerator, at 40 ° C. or higher and 180 ° C. or lower, 1.5% or higher, preferably 1 0.55% or more, more preferably 1.60% or more, still more preferably 1.65% or more, and most preferably 2.00% or more. In other words, it gives a high thermal contraction rate upon cooling. . When a semiconductor device of a thin single-sided sealed package is manufactured with a sealing material made of a curing agent having such a thermal expansion coefficient, the thermal expansion coefficient of the sealing material is high, that is, the thermal contraction rate during cooling is high. As a result, warpage generated in the substrate material on which the semiconductor device is mounted can be reduced.

  From the viewpoint of making the effect of reducing warpage even more remarkable, the phenol resin of the present invention is a cured product obtained from the epoxy resin represented by the general formula (2) and a curing accelerator. It is preferable to give a storage elastic modulus of 15 MPa or more at ° C. From the viewpoint of making the effect of reducing warpage even more pronounced, the phenolic resin of the present invention provides a storage elastic modulus of 15 MPa to 120 MPa, particularly 30 MPa to 110 MPa, particularly 80 MPa to 100 MPa. Even more preferred.

  The measuring method of the thermal expansion coefficient and the storage elastic modulus described above will be described in Examples described later.

  The phenol resin of the present invention can be obtained by reacting a phenol compound represented by the following general formula (3) with formaldehyde under an acidic catalyst or a basic catalyst.

  Examples of the phenol compound represented by the formula (3) include, but are not limited to, ethylphenol, propylphenol, n-butylphenol, tert-butylphenol, octylphenol, allylphenol, dipropylphenol, dibutylphenol and the like. These phenol compounds can be used individually by 1 type or in combination of 2 or more types. In particular, it is preferable to use allylphenol or tert-butylphenol from the viewpoint of increasing the thermal expansion coefficient during heating of the cured product obtained from the phenol resin of the present invention and increasing the thermal shrinkage ratio during cooling. Preference is given to using phenol.

  Formaldehyde, which is a compound that forms a methylene bridging group between the compounds represented by formula (3), is not particularly limited. For example, formaldehyde can be used in the form of its aqueous solution. Alternatively, it can be used in the form of a polymer such as paraformaldehyde or trioxane that decomposes in the presence of an acid to form formaldehyde.

  Preferable phenol resin in the present invention is a narrow dispersion type having a low low molecular weight component, can shorten the gelation time of the epoxy resin composition, and can increase the thermal expansion coefficient of the cured epoxy resin. To preferred. In general formula (1), it is preferable that the number of compounds with n = 0 is small in view of further shortening the gelation time and achieving a high thermal expansion coefficient. From this point of view, in the area ratio based on the chart obtained by measuring the phenol resin of the present invention by gel permeation chromatography, the compound of n = 0 in the general formula (1) is 5.5 based on the whole phenol resin. It is preferably area% or less, more preferably 4.5 area% or less. There is no restriction | limiting in particular in the lower limit of the ratio for which the compound of n = 0 occupies the whole phenol resin, It is so preferable that it is small, Most preferably, it is 0.

  Moreover, from the point which can shorten the gelatinization time of an epoxy resin composition, and the point which can raise the thermal elasticity modulus of an epoxy resin hardened | cured material, in the general formula (1), n = 1 and n = 1 The total content with the compound is preferably 10.0 area% or less, and more preferably 7.0 area% or less. The lower limit of the ratio of the compound of n = 0 and the compound of n = 1 to the entire phenol resin is not particularly limited, but is preferably 4.0% by area or more from the viewpoint of increasing the thermal elastic modulus, More preferably, it is 4.5 area% or more.

  In addition, the content of the compound in which n = 2 in the general formula (1) is 4 because the gelation time of the epoxy resin composition can be shortened and the thermal elastic modulus of the cured epoxy resin can be increased. It is preferably 0.0 area% or more and 14.0 area% or less, and more preferably 5.0 area% or more and 13.5 area% or less.

  In the general formula (1), the total content of the compound where n = 0 and the compound where n = 1 and the content of the compound where n = 2 in the general formula (1) are both within the above range. By doing so, a narrow dispersion type phenol resin having a good balance between the molecular weight distribution and the molecular weight can be obtained, and the softening point and 150 ° C. melt viscosity of the phenol resin can be within a preferable range, and the gelation time of the epoxy resin composition In addition, the thermal expansion coefficient of the cured epoxy resin and the thermal elastic modulus can be increased. For example, the total content of the compound with n = 0 and the compound with n = 1 is less than 4.0 area%, and the content of the compound with n = 2 is less than 4.0 area%. In some cases, the content of a compound having a higher molecular weight (a compound having n = 3 or more) is higher than that of a compound with n = 2, and a high molecular weight is advanced, so that the softening point and the 150 ° C. melt viscosity are increased. It may be too much. Further, even when the total content of the compound where n = 0 and the compound where n = 1 is 10.0 area% or less, the content of the compound where n = 2 is less than 14.0 area%. If it is large, the molecular weight is low, so the softening point and 150 ° C. melt viscosity may be too low.

  Although the weight average molecular weight of the preferable phenol resin in this invention does not specifically limit, Preferably it is 1000 or more and 8000 or less, More preferably, it is 1400 or more and 4000 or less, More preferably, it is 1500 or more and 3000 or less. The value of weight average molecular weight / number average molecular weight, which is the degree of dispersion of the molecular weight distribution, is preferably 1.0 or more and 4.0 or less, more preferably 1.3 or more and 2.5 or less, and still more preferably 1.4 or more and 2. 0 or less. Moreover, by setting both the weight average molecular weight and the dispersity within the above ranges, the gelation time of the epoxy resin composition can be shortened, and the thermal expansion coefficient of the cured epoxy resin can be increased and the elastic modulus during heat can be increased. it can.

  The phenol resin of the present invention can be obtained using the above-described phenol compound and formaldehyde as raw materials in the presence of an acidic catalyst or in the presence of a basic catalyst. The catalyst that can be used includes, for example, oxalic acid, sulfuric acid, paratoluenesulfonic acid and the like when it is an acidic catalyst. In the case of a basic catalyst, for example, alkali metal catalysts such as sodium hydroxide and potassium hydroxide, ammonia, and amine-based catalysts such as triethylamine are exemplified. In particular, it is preferable to use an acid catalyst such as oxalic acid, sulfuric acid, or paratoluenesulfonic acid, and it is particularly preferable to use oxalic acid from the viewpoint of catalyst removal efficiency. In particular, the above-mentioned narrow dispersion type phenol resin is not limited, but for example, a first resolation reaction of a phenol compound represented by the general formula (3) and formaldehyde in the presence of a basic catalyst. Suitable by a production method comprising a step and a second step of adding a phenol compound represented by the general formula (3) to the reaction mixture obtained in the first step and causing a novolak reaction in the presence of an acid catalyst. Can be prepared. In this preparation method, the proportion of the component i component (i represents the component of n = i in the general formula (1)) in the phenol resin, the proportion of the reaction raw material, the reaction time, and the reaction temperature will be described below. It is possible to easily control by adjusting as described above. By conducting preliminary experiments as necessary, those skilled in the art can accurately determine actual reaction conditions.

The first step in the preparation method will be described.
The ratio of the phenol compound represented by the general formula (3) and formaldehyde that reacts in the first step is preferably 1 to 3 with respect to 1 mol of the phenol compound represented by the general formula (3). Mol, more preferably 1.5 to 2.5 mol. By setting the ratio of the phenolic compound and formaldehyde within this range, the production of low molecular weight components can be suppressed, and the components of high molecular weight components can also be suppressed, resulting in a narrow dispersion type phenol resin. .

  Although the usage-amount of the basic catalyst in a 1st process is not limited, It should be a ratio of 0.1-1.5 mol with respect to 1 mol of phenolic compounds represented by General formula (3). Preferably, the ratio is 0.2 to 1.0 mol. By using a basic catalyst at this ratio, the reaction proceeds successfully and it becomes difficult for unreacted components to remain, and the removal of the catalyst becomes easy and productivity is improved. Although reaction temperature is not limited, Preferably it is 10-80 degreeC, More preferably, it is 20-60 degreeC. By setting the reaction temperature within this range, the reaction proceeds successfully, the high molecular weight component can also be suppressed, and the resolation reaction can be easily controlled. Although reaction time is not limited, Preferably it is 0.5 to 24 hours, More preferably, it is 3 to 12 hours.

Next, the second step will be described.
In the second step, preferably, the reaction mixture obtained by the resolation reaction in the first step is neutralized with an acidic compound, then the phenol compound represented by the general formula (3) is added, and an acidic catalyst is further added. Preferred examples of the acidic compound used for neutralization include hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, oxalic acid, butyric acid, lactic acid, benzenesulfonic acid, and p-toluenesulfonic acid. One kind of acidic compound may be used alone, or two or more kinds may be used in combination.

  The phenol compound represented by the general formula (3) used in the second step is preferably 0.5 to 1. per mole of the phenol compound represented by the general formula (3) used in the first step. 5 moles, more preferably 0.7 to 1.1 moles. By setting the amount of the phenolic compound represented by the general formula (3) used in the second step within this range, the generation of a high molecular weight component is suppressed, and the melt viscosity of the phenolic resin can be attributed to that. An excessive increase is suppressed. Moreover, unreacted phenols hardly remain.

  The amount of the acidic catalyst used in the second step is preferably a ratio of 0.0001 to 0.07 mol with respect to 1 mol of the phenol represented by the general formula (3) used in the first step. More preferably, the ratio is 0.0005 to 0.05 mole. By using an acidic catalyst in the range of this ratio, the reaction can proceed successfully, the formation of high molecular weight components is suppressed, and the reaction can be easily controlled. Although reaction temperature is not limited, Preferably it is about 50-150 degreeC, More preferably, it is about 80-120 degreeC, More preferably, it is about 70-100 degreeC. By setting within this temperature range, the reaction can proceed successfully, the formation of high molecular weight components is suppressed, and the novolak reaction can be easily controlled. Although reaction time is not limited, Preferably it is 0.5 to 12 hours, More preferably, it is 1 to 6 hours. By setting the reaction time within this range, the reaction can proceed successfully, and the production of high molecular weight components is suppressed. Examples of the acidic catalyst used in the second step include the same acidic compounds used in the same step.

  Next, the epoxy resin composition of the present invention comprising the phenol resin will be described. The epoxy resin used in the epoxy resin composition of the present invention is not particularly limited. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol aralkyl type epoxy resin, cresol novolak type epoxy resin, phenol novolak type epoxy resin. , Glycidyl ether type epoxy resin such as triphenolmethane type epoxy resin, biphenyl type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, halogenated epoxy resin, etc. epoxy resin having two or more epoxy groups in the molecule, etc. Is mentioned. These epoxy resins may be used individually by 1 type, and may use 2 or more types together. A particularly preferable epoxy resin is the biphenyl type epoxy resin represented by the general formula (2) described above.

  The addition ratio of the epoxy resin used in the epoxy resin composition of the present invention is the ratio of the hydroxyl equivalent (g / eq) of the phenol resin represented by the formula (1) to the epoxy equivalent in the epoxy resin. Is preferably in the range of 0.5 to 2.0, more preferably in the range of 0.8 to 1.2. By setting the value of hydroxyl equivalent / epoxy equivalent within this range, the curing reaction can sufficiently proceed, and it is possible to effectively prevent the unreacted curing agent and epoxy resin from remaining. Thereby, a cured product having a high coefficient of thermal expansion when heated, and thus having a high coefficient of thermal shrinkage when cooled can be obtained.

  The phenol resin represented by the formula (1) has a role of a curing agent for the epoxy resin in the epoxy resin composition of the present invention, and the epoxy resin composition of the present invention is a phenol represented by the formula (1). A curing agent other than the resin may be included. There is no limitation in particular in the kind of hardening | curing agents other than the phenol resin represented by Formula (1), According to the intended purpose of an epoxy resin composition, various hardening | curing agents can be used. For example, an amine curing agent, an amide curing agent, an acid anhydride curing agent, or the like can be used.

  In the epoxy resin composition of the present invention, the proportion of the phenol resin represented by the formula (1) in all the curing agents is sufficient for high expansion during heating of the cured product obtained from the epoxy resin composition. From the viewpoint of increasing the temperature and, in turn, sufficiently increasing the high heat shrinkability during cooling, a higher ratio is preferable. Specifically, the proportion of the phenol resin represented by the formula (1) in all the curing agents is preferably 30% by mass or more, more preferably 50% by mass or more, and further preferably 70% by mass or more. More preferably, it is 90 mass%, Most preferably, it is 100 mass%.

  In the epoxy resin composition of this invention, the other component used with a normal epoxy resin composition can be used suitably according to the use. For example, a curing accelerator for curing an epoxy resin with a phenol resin can be used. Preferred examples of the curing accelerator include known organic phosphine compounds and their boron salts, tertiary amines, quaternary ammonium salts, imidazoles and their tetraphenylboron salts. Among these, it is preferable to use triphenylphosphine from the viewpoints of curability and moisture resistance. In addition, when the high fluidity | liquidity is requested | required of an epoxy resin composition, it is preferable to use the heat | fever latent hardening accelerator which expresses activity by heat processing. Examples of such a curing accelerator include tetraphenylphosphonium derivatives such as tetraphenylphosphonium and tetraphenylborate. The ratio of the curing accelerator added to the epoxy resin composition can be the same as the ratio in the known epoxy resin composition.

  Further, a filler such as an inorganic filler can be suitably blended in the epoxy resin composition of the present invention. As the inorganic filler, for example, amorphous silica, crystalline silica, alumina, calcium silicate, calcium carbonate, talc, mica, barium sulfate and the like can be used. In particular, it is preferable to use amorphous silica and crystalline silica. Although there is no restriction | limiting in particular in the particle size of an inorganic filler, when a filling rate is considered, it is desirable that it is 0.01 micrometer or more and 150 micrometers or less. Although there is no restriction | limiting in particular in the mixture ratio of an inorganic filler, It is preferable that the ratio of the inorganic filler to an epoxy resin composition is 70 to 95 mass%, and it is 70 to 90 mass%. Is more preferable. Setting the blending ratio of the inorganic filler within this range is preferable because the water absorption rate of the cured product of the epoxy resin composition is difficult to increase. Moreover, the thermal expansion property at the time of heating of this hardened | cured material becomes high enough, and, thereby, the heat-shrinkability at the time of cooling becomes high enough, and also it becomes difficult for fluidity | liquidity to be impaired, and it is preferable.

  If necessary, the epoxy resin composition of the present invention may be added with a release agent, a colorant, a coupling agent, a flame retardant, or the like, or may be reacted in advance. The mixing ratio of these additives may be the same as the ratio in the known epoxy resin composition. In addition to this, the epoxy resin composition of the present invention contains a nitrogen-based flame retardant such as melamine and an isocyanuric acid compound, and a phosphorus-based flame retardant such as red phosphorus, a phosphoric acid compound and an organic phosphorus compound, if necessary. It can be added appropriately as a combustion aid.

  To prepare the epoxy resin composition of the present invention, for example, a phenol resin, an epoxy resin, and a curing accelerator, an inorganic filler, and other additives that are added as necessary are uniformly mixed using a mixer or the like. The kneaded material is kneaded in a molten state using a kneader such as a heating roll, a kneader, or an extruder, the kneaded product is cooled, and pulverized as necessary.

  The epoxy resin composition thus obtained is not particularly limited, but can be suitably used as a sealing material for sealing a semiconductor element. For example, after a lead frame or the like on which the semiconductor element is mounted is placed in a metal cavity, an epoxy resin composition is molded by a molding method such as a transfer mold, a compression mold, or an injection mold, and the temperature is about 120 ° C. to 300 ° C. A semiconductor device can be suitably obtained by curing the epoxy resin composition by heat treatment or the like. In particular, when the semiconductor device is formed of a thin single-sided sealed package, the cured product of the epoxy resin composition has a high expansibility, so that the cured product is greatly shrunk when cooled, thereby causing warping. There is an advantageous effect that generation can be effectively reduced.

  The present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass”. “%” Indicates “mass%”.

[1] Preparation of phenol resin The analysis method and evaluation method used in the following examples of preparation of phenol resin will be described.
<Softening point> The softening point was determined by ring and ball softening point measurement based on JIS K6910.
<150 ° C. melt viscosity> Using an ICI melt viscometer, the melt viscosities of phenol resin and epoxy resin at 150 ° C. were measured.
The measuring method of ICI viscosity is as follows.
ICI Cone Plate Viscometer MODEL CV-1S TOA Industrial Co., Ltd.
The plate temperature of the ICI viscometer is set to 150 ° C., and a predetermined amount of the sample is weighed.
Place the weighed resin on the plate, press it with a cone from the top, and leave it for 90 seconds. The cone is rotated and its torque value is read as ICI viscosity.
<Hydroxyl equivalent> It was determined by measuring the hydroxyl equivalent according to JIS K0070.
<Measurement of molecular weight distribution> The molecular weight distribution of the phenol resin was measured by gel permeation chromatography as follows. The ratio of i component (i represents the component of n = i in General formula (1)) in the phenol resin was calculated based on the peak area in the measured chart using analysis software Multi Station GPC-8020. At that time, the straight line part before and after the peak was taken as the baseline (zero value), and the peak was divided by the vertical cut at the lowest point between the peaks of each component. The sampling pitch was 500 milliseconds. Moreover, molecular weight (Mw, Mn) and dispersity (Mw / Mn) were calculated by standard polystyrene conversion.
Apparatus: HLC-8220 (manufactured by Tosoh Corporation, gel permeation chromatograph analyzer)
Column: TSK-GEL H type
G2000H × L 4
1 G3000H x L
One G4000H × L Measurement condition: Column pressure 13.5 MPa
Solution: Tetrahydrofuran (THF)
Flow rate: 1 mL / min Measurement temperature: 40 ° C
Detector: RI detector RANGE: 256 (Recorder output: 256 × 10 ⁻⁶ RIU / 10 mV)
Temperature control (temperature control temperature of RI optical block): 40 ° C
Injection volume: 100 μmL
Sample concentration: 5 mg / mL (THF)
<Measurement of molecular weight (Mw, Mn) and dispersity (Mw / Mn)> The molecular weight (Mw, Mn) and dispersity (Mw / Mn) of the phenol resin were measured by gel permeation chromatography as follows. The ratio of i component (i represents the component of n = i in General formula (1)) in the phenol resin was calculated based on the peak area in the measured chart using analysis software Multi Station GPC-8020. At that time, the straight line part before and after the peak was taken as the baseline (zero value), and the peak was divided by the vertical cut at the lowest point between the peaks of each component. The sampling pitch was 500 milliseconds. Moreover, molecular weight (Mw, Mn) and dispersity (Mw / Mn) were calculated by standard polystyrene conversion.
Apparatus: HLC-8220 (manufactured by Tosoh Corporation, gel permeation chromatograph analyzer)
Column: TSK-GEL H type
G2000H × L 4
1 G3000H x L
One G4000H × L Measurement condition: Column pressure 13.5 MPa
Solution: Tetrahydrofuran (THF)
Flow rate: 1 mL / min Measurement temperature: 40 ° C
Detector: Spectrophotometer (UV-8020)
RANGE: 2.56
WAVE LENGTH: 254nm
Injection volume: 100 μmL
Sample concentration: 5 mg / mL (THF)
<Gelification time>
Equipment used: Cyber Co., Ltd. Automatic curing time measuring device Measuring conditions: 150 ° C 600 rpm
Measurement method: o-cresol type epoxy resin EOCN-1020-55 (manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 195 g / eq) and the hydroxyl equivalent of the phenolic resin equivalent ratio (ratio of epoxy equivalent to hydroxyl equivalent) Mixing in 1), an epoxy resin composition in which 1.9% of triphenylphosphine as a curing accelerator is blended with respect to the epoxy resin is prepared in a 50% methyl ethyl ketone (MEK) solution. About 0.6 mL of the MEK solution of the epoxy resin composition is weighed and placed on the hot plate of the apparatus for measurement. The time when the measured torque was 20% of the measurement upper limit torque value of the apparatus was defined as the gel time.

[Example 1]
In a glass flask having a capacity of 300 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 134 parts (1.0 mol) of o-allylphenol, 32 parts (0.98 mol) of 92% paraformaldehyde, 0.4 parts of pure water and 1.1 parts of oxalic acid were added. The mixture was reacted at 100 ° C. for 12 hours under reflux, further reacted at 160 ° C. for 2 hours, and then cooled to 95 ° C. After cooling, 130 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature is raised to 160 ° C., a decompression-steaming treatment is performed, and unreacted components are removed, whereby phenol novolak resin A (R in the general formula (1) is an allyl group, p = 1, q = 1 phenol novolac resin). The obtained phenol novolac resin A had a softening point of 73 ° C., a melt viscosity at 150 ° C. of 4.3 P, a hydroxyl group equivalent of 170 g / eq, and a gel time of 72 seconds. According to the gel permeation chromatographic measurement, the compound with n = 0 was 5.9 area% of the entire phenol resin, and the compound with n = 1 was 6.2 area% of the entire phenol resin.

[Example 2]
In a glass flask having a capacity of 300 parts equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 134 parts (1.0 mol) of o-allylphenol, 36 parts of 92% paraformaldehyde (1.1 mol), 0.4 parts of pure water and 1.1 parts of oxalic acid were added. The mixture was reacted at 100 ° C. for 12 hours under reflux, further reacted at 160 ° C. for 2 hours, and then cooled to 95 ° C. After cooling, 130 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature is raised to 160 ° C., a decompression-steaming treatment is performed, and unreacted components are removed, whereby phenol novolak resin B (R in the general formula (1) is an allyl group, p = 1, q = 1 phenol novolac resin). The obtained phenol novolac resin B had a softening point of 98 ° C., a melt viscosity at 150 ° C. of 20 P, and a hydroxyl group equivalent of 172 g / eq.

Example 3
In a glass flask having a capacity of 2000 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 1200 parts (9.0 moles) of o-allylphenol, 127 parts (1.8 moles) of 42% formalin, and 12 parts of oxalic acid was added. The mixture was reacted at 100 ° C. for 7 hours under reflux. After completion of the reaction, 600 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature is raised to 160 ° C., a decompression-steaming treatment is performed, and unreacted components are removed to remove phenol novolac resin C (R in the general formula (1) is an allyl group, p = 1, q = 1 phenol novolac resin). The obtained phenol novolac resin C was liquid at room temperature, and the hydroxyl group equivalent was 141 g / eq.

Example 4
95 parts (0.5 mol) of diallyl resorcin and 14 parts (0.2 mol) of 42% formalin were placed in a glass flask having a capacity of 300 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer. The mixture was reacted at 100 ° C. for 12 hours under reflux, and then cooled to 95 ° C. After cooling, 110 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C. and the pressure was reduced to obtain a phenol novolac resin D (R in the general formula (1) is an allyl group, p = 2, q = 2 phenol novolac resin). The obtained phenol novolac resin D was liquid at normal temperature and the hydroxyl group equivalent was 108 g / eq.

Example 5
To a glass flask having a capacity of 1000 parts equipped with a thermometer, charging / distilling outlet, condenser and stirrer, p-tert-butylphenol 200 parts (1.3 mol), 42% formalin 57 parts (0.8 mol), 0.3 parts of oxalic acid was added. The mixture was reacted at 100 ° C. for 20 hours under reflux, and then cooled to 95 ° C. After cooling, 130 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature is raised to 180 ° C., a decompression-steaming treatment is performed, and unreacted components are removed, whereby phenol novolak resin E (R in the general formula (1) is a tert-butyl group, p = 1) , Q = 1 phenol novolac resin). The obtained phenol novolac resin E had a softening point of 99 ° C., an ICI viscosity at 150 ° C. of 4.3 P, and a hydroxyl group equivalent of 167 g / eq.

Example 6
In a glass flask with a capacity of 300 parts (300 mL) equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 67.0 parts (0.50 mol) of o-allylphenol, 71.4 parts of 42% formalin (1.00 mol) and 19.2 parts (0.12 mol) of 25% sodium hydroxide as a basic catalyst were added and reacted at 60 ° C. for 7 hours to carry out a resolation reaction in the first step. To this reaction mixture, 134 parts of pure water for stopping the reaction was added, the temperature was lowered to 40 ° C., and 17.5 parts (0.12 mol) of 25% hydrogen chloride was added to neutralize to obtain a reaction mixture. It was. Next, 73.7 parts (0.55 mol) of o-allylphenol and 1.3 parts of oxalic acid as an acid catalyst were added to the reaction mixture, and reacted at 100 ° C. for 2 hours and then at 120 ° C. for 2 hours. A novolak reaction of the process was performed. The resulting reaction mixture was cooled to 95 ° C. and washed with 134 parts of pure water at the same temperature. After washing with water, the temperature was raised to 160 ° C., a steaming treatment was performed, and unreacted components were removed, whereby phenol novolac resin I (R in the general formula (1) was an allyl group, p = 1, q = 1. Phenol novolac resin). The obtained phenol novolac resin I had a softening point of 59 ° C., an ICI viscosity of 1.2 P at 150 ° C., a hydroxyl group equivalent of 154 g / eq, and a gelation time of 59 seconds. According to the gel permeation chromatographic measurement, the compound with n = 0 was 3.5 area% of the entire phenol resin, and the compound with n = 1 was 6.0 area% of the entire phenol resin.

Example 7
In a glass flask having a capacity of 300 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 67.0 parts (0.50 mol) of o-allylphenol, 71.4 parts of 42% formalin (1. 00 mol) and 19.2 parts (0.12 mol) of 25% sodium hydroxide as a basic catalyst were added and reacted at 60 ° C. for 7 hours to carry out a resorching reaction in the first step. To this reaction mixture, 134 parts of pure water for stopping the reaction was added, the temperature was lowered to 40 ° C., and 17.5 parts (0.12 mol) of 25% hydrogen chloride was added to neutralize to obtain a reaction mixture. It was. Next, 60.3 parts (0.45 mol) of o-allylphenol and 1.3 parts of oxalic acid as an acid catalyst were added to the reaction mixture, and reacted at 100 ° C. for 2 hours and then at 120 ° C. for 2 hours. A novolak reaction of the process was performed. Thereafter, in the same manner as in Example 6, a phenol novolac resin J (Phenol novolac resin in which R in the general formula (1) is an allyl group, p = 1, q = 1) was obtained. The obtained phenol novolac resin J had a softening point of 74 ° C., an ICI viscosity of 4.3 P at 150 ° C., a hydroxyl group equivalent of 159 g / eq, and a gel time of 55 seconds. According to gel permeation chromatographic measurement, the compound with n = 0 was 1.9 area% of the entire phenol resin, and the compound with n = 1 was 4.1 area% of the entire phenol resin.

Example 8
In a glass flask having a capacity of 300 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 67.0 parts (0.50 mol) of o-allylphenol, 71.4 parts of 42% formalin (1. 00 mol) and 19.2 parts (0.12 mol) of 25% sodium hydroxide as a basic catalyst were added and reacted at 60 ° C. for 7 hours to carry out a resorching reaction in the first step. To this reaction mixture, 134 parts of pure water for stopping the reaction was added, the temperature was lowered to 40 ° C., and 17.5 parts (0.12 mol) of 25% hydrogen chloride was added to neutralize to obtain a reaction mixture. It was. Next, 46.9 parts (0.35 mol) of o-allylphenol and 1.3 parts of oxalic acid as an acid catalyst were added to the reaction mixture, and the mixture was reacted at 100 ° C. for 2 hours and then at 120 ° C. for 2 hours. A novolak reaction of the process was performed. Thereafter, in the same manner as in Example 6, a phenol novolac resin K (Phenol novolac resin in which R in the general formula (1) is an allyl group, p = 1, q = 1) was obtained. The obtained phenol novolak resin K had a softening point of 91 ° C., an ICI viscosity of 29 P at 150 ° C., a hydroxyl group equivalent of 159 g / eq, and a gelation time of 51 seconds. According to gel permeation chromatographic measurement, the compound of n = 0 was 1.4 area% of the whole phenol resin, and the compound of n = 1 was 2.8 area% of the whole phenol resin.

[Comparative Example 1]
In a glass flask having a capacity of 1000 parts equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 513 parts (5.5 mol) of phenol, 229 parts (3.3 mol) of 42% formalin, and 0 oxalic acid .6 parts were added. The mixture was reacted at 100 ° C. for 6 hours under reflux. After completion of the reaction, the internal temperature was raised to 160 ° C., a decompression-steaming treatment was performed, and unreacted components were removed, whereby phenol novolac resin F (p = 1, q = 0 in the general formula (1)) Phenol novolac resin) was obtained. The obtained phenol novolac resin F had a softening point of 83 ° C., an ICI viscosity of 2.0 P at 150 ° C., and a hydroxyl group equivalent of 107 g / eq.

[Comparative Example 2]
In a glass flask having a capacity of 300 parts equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 108 parts (1.0 mol) of o-cresol, 32 parts (0.98 mol) of 92% paraformaldehyde, pure 0.4 parts of water and 1.1 parts of oxalic acid were added. The mixture was reacted at 100 ° C. for 6 hours under reflux, and further reacted at 160 ° C. for 2 hours. After completion of the reaction, a decompression-steaming treatment is performed to remove unreacted components, whereby a phenol novolac resin G (R in the general formula (1) is a methyl group, p = 1, q = 1 phenol novolac resin). Obtained. The resulting phenol novolac resin G had a softening point of 130 ° C., but the ICI viscosity at 150 ° C. could not be measured. The hydroxyl equivalent was 116 g / eq.

[Comparative Example 3]
In a glass flask having a capacity of 300 parts equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 170 parts (1.0 mol) of o-phenylphenol, 42 parts (42 mol) of 42% formalin, and 3.8 parts of paratoluenesulfonic acid were added. The mixture was reacted at 100 ° C. for 7 hours under reflux, and then cooled to 95 ° C. After cooling, the mixture was neutralized with 25% aqueous sodium hydroxide solution. Further, 340 parts of pure water having a temperature of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature is raised to 160 ° C., a decompression-steaming treatment is performed, and unreacted components are removed, whereby phenol novolak resin H (R in the general formula (1) is a phenyl group, p = 1, q = 1 phenol novolac resin). The obtained phenol novolac resin H had a softening point of 81 ° C., an ICI viscosity at 150 ° C. of 1.7 P, and a hydroxyl group equivalent of 188 g / eq.

  Using the phenol resins obtained in Examples and Comparative Examples, an epoxy resin composition was prepared, and the cured product characteristics of the cured product obtained from the epoxy resin composition were measured. The results are summarized in Table 1.

[2] Preparation and Evaluation of Epoxy Resin Composition and Cured Product The phenol resin obtained in Examples and Comparative Examples, and the biphenyl type epoxy resin represented by the general formula (2) (YX-manufactured by Mitsubishi Chemical Corporation) 4000 epoxy equivalent: 186 g / eq) and triphenylphosphine (TPP manufactured by Hokuko Chemical Co., Ltd.) as a curing accelerator were used to prepare an epoxy resin composition. In preparation, the phenol resin and the epoxy resin are blended so that the value of [hydroxyl equivalent (g / eq) / epoxy equivalent (g / eq)], which is the ratio of the hydroxyl equivalent to the epoxy equivalent, is 1. The mixture was heated and melted and mixed, and then the amount of triphenylphosphine shown in Table 1 was added and mixed uniformly to obtain an epoxy resin composition. The obtained epoxy resin composition was post-cured at 150 ° C. for 5 hours and at 180 ° C. for 8 hours to obtain a cured epoxy resin. About the obtained epoxy resin hardened | cured material, the thermal expansion coefficient, the glass transition point, the linear expansion coefficient, and the storage elastic modulus were measured.

The analysis method and the evaluation method used in the example of the cured product of the epoxy resin composition will be described.
(1) Storage elastic modulus The epoxy cured product was cut into 40 mm × 2 mm × 4 mm and used as a measurement sample. The measurement is performed using a dynamic viscoelasticity measuring device RSA-G2 manufactured by TA Instruments Inc., measuring the storage elastic modulus while increasing the temperature from 30 ° C. at a rate of 3 ° C./min, at 250 ° C. The storage elastic modulus was determined. The peak temperature of Tan δ was defined as Tg.
(2) Glass transition temperature (Tg), coefficient of linear expansion (α1, α2) and coefficient of thermal expansion An epoxy cured product was cut into 10 mm × 6 mm × 4 mm and used as a measurement sample. Using a thermomechanical analyzer TMA-60 manufactured by Shimadzu Corporation, the glass transition temperature and linear expansion coefficient (α1, α2) of the sample were measured while increasing the temperature from 30 ° C. at a rate of 3 ° C./min. The linear expansion coefficient from 40 ° C to 70 ° C was α1, and the linear expansion coefficient from 185 ° C to 220 ° C was α2. Moreover, the thermal expansion coefficient of the sample in 40 to 180 degreeC was calculated | required.

As is apparent from the results shown in Table 1, the cured epoxy resin obtained using the phenol novolak resin obtained in each example is the epoxy resin obtained using the phenol novolak resin obtained in each comparative example. It can be seen that the coefficient of thermal expansion is higher when heated compared to the cured product, in other words, the coefficient of thermal shrinkage is high when cooled, and the storage modulus is high.
In particular, as is clear from the comparison between Example 1 and Examples 6 to 8, the ratio of the compound of n = 0 in the general formula (1) is set to a small amount of 5% or less with respect to the whole phenol novolac resin. Thus, the coefficient of thermal expansion of the cured product can be increased and the gelation time can be shortened.
Further, as is clear from the comparison between Example 1 and Examples 6 to 8, the total ratio of the compound of n = 0 and the compound of n = 1 in the general formula (1) is based on the whole phenol novolac resin. By setting it to 10% or less, the thermal expansion coefficient of the cured product can be increased, and the gelation time can be shortened.
Further, as is clear from comparison with Examples 6 to 8, the total ratio of the compound of n = 0 and the compound of n = 1 in the general formula (1) is 10% or less with respect to the whole phenol novolac resin. In addition, by setting the ratio of the compound where n = 2 to 5.0% or more and 13.5% or less, the thermal expansion coefficient of the cured product can be increased, and the gelation time can be shortened and stored. The elastic modulus (thermal elastic modulus) can be increased.
In addition, as is clear from the comparison between Examples 1, 2, 4 and 7 (substituent R is an allyl group) and Comparative Examples 1, 2 and 3 (substituent R is other than an allyl group), the substituent R is an allyl group. By doing so, the coefficient of thermal expansion of the cured product can be increased, and the elastic modulus during heating can also be increased. The same is apparent from the comparison between Example 1 (substituent R is an allyl group) and Example 5 (substituent R is a tert-butyl group).
Further, Example 1 (150 ° C. melt viscosity: 4.3 P, softening point: 73 ° C., storage elastic modulus 86 MPa) and Example 2 (150 ° C. melt viscosity: 20.0 P, softening point: 98 ° C., storage elastic modulus: As is clear from the comparison with 33 MPa), the 150 ° C. melt viscosity value is more preferably 0.1 P or more and less than 20.0 P, further preferably 0.1 P or more and 10.0 P or less, and further preferably 0.1 P or more and 7 or less. When a cured product is produced using a phenol novolac resin having a viscosity of 0.0 P or less, and most preferably 0.1 P or more and 5.0 P or less, the thermal modulus of the cured product can be increased. The same applies to Example 7 (150 ° C. melt viscosity: 4.3 P, softening point: 74 ° C., storage modulus 96 MPa) and Example 8 (150 ° C. melt viscosity: 29.0 P, softening point: 91 ° C., It is also clear by comparison with the storage elastic modulus 26 MPa).
Further, Example 4 (substituent R: allyl group, p = 2, q = 2, softening point: liquid, 150 ° C. melt viscosity: <0.1, storage modulus 100 MPa) and Example 3 (substituent R) : Allyl group, p = 1, q = 1, softening point: liquid, 150 ° C. melt viscosity: <0.1, storage elastic modulus 19 MPa, q (allyl bonded to one phenol nucleus) When the number of groups is more than 1 (when it is 2 or more), even when the phenol novolak resin has a low melt viscosity at 150 ° C., for example, less than 0.1 P, it is cured with a high thermal modulus. You can get a body.

  As described above in detail, by using the phenol resin of the present invention, it is possible to obtain a cured product of an epoxy resin composition having a high thermal expansion coefficient during heating, that is, a high shrinkage ratio during cooling, and an elastic modulus during high heat. it can. Therefore, according to this invention, the phenol resin which can be used suitably for the epoxy resin composition of a thin single-sided sealing package can be provided.

Claims (13)

A phenol resin represented by the following general formula (1),

The phenol resin includes the phenol resin and the following general formula (2).

The phenol resin which gives the thermal expansion coefficient of 1.5% or more to the hardened | cured material obtained from the epoxy resin represented by these, and a hardening accelerator in 40 to 180 degreeC.   The phenol resin according to claim 1, wherein the cured product is given a storage elastic modulus of 15 MPa or more at 250 ° C.   The phenol resin according to claim 1 or 2, wherein R in the general formula (1) is an allyl group, p is 1 or 2, and q is 1 or 2.   The phenol resin according to any one of claims 1 to 3, which has a softening point of 60 ° C or higher and 90 ° C or lower.   5. The phenol resin according to claim 1, wherein in the molecular weight distribution measured by gel permeation chromatography, the content of the compound where n = 0 in the general formula (1) is 5.5 area% or less. .   The phenol resin according to any one of claims 1 to 5, wherein the degree of dispersion [weight average molecular weight / number average molecular weight] measured by gel permeation chromatography is 1.0 or more and 4.0 or less.   The epoxy resin composition containing the phenol resin and epoxy resin as described in any one of Claims 1 thru | or 6.   Furthermore, the epoxy resin composition of Claim 7 containing a hardening accelerator.   The epoxy resin composition according to claim 7 or 8, further comprising an inorganic filler.   An epoxy resin cured product obtained by curing the epoxy resin composition according to any one of claims 7 to 9.   The cured epoxy resin product according to claim 10, which has a coefficient of thermal expansion of 1.5% or more at 40 ° C. or more and 180 ° C. or less.   A semiconductor device comprising the cured epoxy resin according to claim 10.   The semiconductor device according to claim 12, comprising a thin single-side sealed package.