JP2011093971A - Manufacturing method for liquid crystal resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To industrially and efficiently produce a liquid crystal resin used as a material for an insulating resin substrate for a printed wiring board, a package substrate, and the like by a batch polymerization process. <P>SOLUTION: A resin producing process of producing a liquid crystal resin P by melt polymerization of a material M in a polymerization vessel 3, and a resin ejecting process of ejecting the liquid crystal resin P produced in the resin producing process from the polymerization vessel 3 are executed repeatedly for a plurality of lots. The liquid crystal resin P remaining in a molten state at an outlet 3c of the polymerization vessel 3 is re-ejected from the polymerization vessel 3 by a gauge pressure higher than 0.005 MPa after the resin ejecting process for each lot and before the resin producing process of the subsequent lot. Thus, choking of the outlet 3c of the polymerization vessel 3 by solidification of the liquid crystal resin P remaining in the polymerization vessel 3 is avoided. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a liquid crystal resin suitable for use as a material for an insulating resin base material on a substrate such as a printed wiring board (printed circuit board or printed circuit board) or a package substrate.

  Conventionally, in this type of substrate, an insulating resin base material that is used with a conductive layer attached to the surface is used, and this insulating resin base material has heat resistance, electrical characteristics, low moisture absorption, dimensions. Characteristics such as stability are required. Conventionally, as such an insulating resin base material, a base material in which a glass cloth is impregnated with an epoxy resin has been widely used.

  However, with the recent increase in the digital signal propagation speed (several hundred MHz or more) of electronic devices, the digital signal frequency has been increased, and an insulating resin substrate having higher electrical characteristics (low dielectric loss tangent). Materials are desired. For this reason, a base material obtained by impregnating a conventional glass cloth with an epoxy resin is not always capable of sufficiently dealing with it.

  Therefore, in order to meet such a demand, for example, Patent Document 1 proposes a resin-impregnated base material impregnated with a solvent-soluble liquid crystal resin, which can maintain solder heat resistance in addition to high electrical characteristics. Is disclosed. This solvent-soluble liquid crystal resin has an amide bond as part of the bond.

  When such a liquid crystal resin is produced industrially, a batch polymerization method is generally widely employed (for example, see Patent Document 2). In this batch polymerization method, the raw material to be polymerized is divided into a plurality of lots (equivalent to one batch) in advance, and then the raw material is charged into the polymerization vessel for the first lot, and this raw material is polymerized to obtain a liquid crystal resin. (Polymer) is generated and the liquid crystal resin is discharged from the discharge port of the polymerization container. Then, for the next lot, the raw material is put into the same polymerization container, and the raw material is polymerized to form a liquid crystal resin. This means a polymerization method in which the polymerization of all the raw materials is performed by repeating the same procedure until the polymerization operation of the raw materials of the last lot is completed after the resin is discharged from the discharge port of the polymerization container.

JP 2007-146139 A JP-A-6-192403

  However, a liquid crystal resin having a specific structure, particularly a liquid crystal resin containing a lot of amide bonds, has a glass transition temperature (glass transition point). There was a problem that productivity could not be increased due to inconvenience in manufacturing.

  That is, since the liquid crystal resin produced in the polymerization vessel has a predetermined viscosity, even when discharged from the discharge port of the polymerization vessel, a part of the liquid crystal resin remains attached to the inner wall of the polymerization vessel. Thus, the liquid crystal resin remaining in the polymerization vessel flows and accumulates at the discharge port of the polymerization vessel over time, and when the temperature drops below the glass transition temperature and solidifies, the discharge port of the polymerization vessel is blocked. Therefore, the liquid crystal resin discharge operation cannot be executed for the next lot, and batch polymerization cannot be repeated.

  Therefore, in view of such circumstances, the present invention provides a liquid crystal resin that can be industrially efficiently produced by a batch polymerization method even when the liquid crystal resin has a glass transition temperature. An object is to provide a manufacturing method.

  In order to achieve such an object, the present inventor has intensively studied, and in order to avoid occurrence of a situation in which the liquid crystal resin remaining in the polymerization vessel is solidified to block the discharge port of the polymerization vessel, the liquid crystal resin is added to the polymerization vessel. Focusing on re-discharge of the liquid crystal resin by applying a predetermined pressure after discharging from the liquid, the present invention has been completed.

  That is, the invention according to claim 1 is a resin generation step in which a raw material is melt-polymerized in a polymerization vessel to generate a liquid crystal resin, and a resin discharge in which the liquid crystal resin generated in the resin generation step is discharged from the polymerization vessel. The process is a liquid crystal resin manufacturing method that is repeatedly executed for a plurality of lots, and the polymerization is performed after the resin discharge process for each lot and before the resin generation process for the next lot of the lot. A method for producing a liquid crystal resin in which a resin re-discharge process for re-discharging the liquid crystal resin remaining in a molten state at a discharge port of the container from the polymerization container at a gauge pressure exceeding 0.005 MPa is incorporated. To do.

  The invention described in claim 2 is characterized in that, in addition to the structure described in claim 1, the liquid crystal resin is a liquid crystal resin having a glass transition temperature in a range of 50 to 200 ° C.

  In addition to the constitution described in claim 1 or 2, the invention described in claim 3 is characterized in that the liquid crystal resin includes a monomer unit having a 1,3-phenylene skeleton, a monomer unit having a 2,3-phenylene skeleton, and It is a liquid crystal resin containing at least one monomer unit selected from the group consisting of monomer units having a 2,3-naphthalene skeleton in a proportion of 10 to 45 mol% with respect to the total structural units.

According to a fourth aspect of the present invention, in addition to the structure according to any one of the first to third aspects, the liquid crystal resin is a structural unit represented by the following formulas (1), (2) and (3): The content of the structural unit represented by the formula (1) is 20 to 70 mol% and the content of the structural unit represented by the formula (2) is 40 to 15 mol% with respect to the total of all the structural units. The liquid crystal resin is characterized in that the content of the structural unit represented by formula (3) is 40 to 15 mol%.
(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
⁽³⁾ -X-Ar 3 -Y-
(In the formula, Ar ¹ represents a phenylene group or a naphthylene group, Ar ² represents a phenylene group, a naphthylene group, or a group represented by the following formula (4), and Ar ³ represents a phenylene group or the following formula (4). X and Y each independently represents O or NH, wherein the hydrogen atom bonded to the aromatic ring of Ar ¹ , Ar ² and Ar ³ is a halogen atom or an alkyl group Or it may be substituted with an aryl group.)
^{(4) -Ar 11 -Z-Ar} 12 -
(In the formula, Ar ¹¹ and Ar ¹² each independently represent a phenylene group or a naphthylene group, and Z represents O, CO, or SO _2. )

  Further, the invention described in claim 5 is characterized in that, in addition to the structure described in claim 4, at least one of X and Y of the structural unit represented by the formula (3) is NH.

  According to the present invention, the liquid crystal resin remaining in the polymerization container is incorporated by incorporating a resin re-discharge process in which the liquid crystal resin is re-discharged from the polymerization container at a predetermined pressure after the resin discharge process of discharging the liquid crystal resin from the polymerization container. It is possible to avoid the occurrence of a situation where the solidifies and blocks the discharge port of the polymerization vessel. As a result, even when the liquid crystal resin has a glass transition temperature, the liquid crystal resin can be industrially efficiently produced by a batch polymerization method.

It is a schematic block diagram which shows the manufacturing equipment which concerns on Embodiment 1 of this invention. FIG. 6 is a cross-sectional view showing a flow state of the liquid crystal resin when the discharge pressure of the liquid crystal resin in the resin re-discharge process is higher than a predetermined threshold, where (a) is a state diagram immediately before the resin re-discharge process, It is a state figure immediately after a resin re-discharge process. It is sectional drawing which shows the flow state of liquid crystal resin when the discharge pressure of the liquid crystal resin in a resin re-discharge process is below a predetermined threshold value, Comprising: (a) is a state figure just before a resin re-discharge process, (b) These are state diagrams immediately after the resin re-discharge process.

Embodiments of the present invention will be described below.
Embodiment 1 of the Invention

FIG. 1 shows a first embodiment of the present invention.
<Configuration of liquid crystal resin>

  The liquid crystal resin according to the present invention is a thermotropic liquid crystal resin exhibiting liquid crystallinity when melted, and in particular, a liquid crystal resin having a glass transition temperature. The glass transition temperature can be observed by differential scanning calorimetry (DSC) in the range of 50 to 200 ° C.

  Examples of the liquid crystal resin include wholly aromatic polyesters, wholly aromatic polyester amides, aromatic-aliphatic polyesters, aromatic-aliphatic polyester amides, etc., and monomer units having a 1,3-phenylene skeleton, 2, A liquid crystal resin comprising at least one monomer unit selected from the group consisting of a monomer unit having a 3-phenylene skeleton and a monomer unit having a 2,3-naphthalene skeleton in a proportion of 10 to 45 mol% based on the total structural units. It is preferable.

Examples of such a liquid crystal resin include a structural unit represented by the following formula (1) (hereinafter referred to as “formula (1) structural unit”) and a structural unit represented by the following formula (2) (hereinafter referred to as “formula”). (2) Structural Unit ”) and a structural unit represented by the following Formula (3) (hereinafter referred to as“ Formula (3) Structural Unit ”). ) Is 20 to 70 mol%, the content of the structural unit represented by the formula (2) is 40 to 15 mol%, and the content of the structural unit represented by the formula (3) is 40 to 40 mol%. A 15 mol% liquid crystal resin is preferred.
(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
⁽³⁾ -X-Ar 3 -Y-
(In the formula, Ar ¹ represents a phenylene group or a naphthylene group, Ar ² represents a phenylene group, a naphthylene group, or a group represented by the following formula (4), and Ar ³ represents a phenylene group or the following formula (4). X and Y each independently represents O or NH, wherein the hydrogen atom bonded to the aromatic ring of Ar ¹ , Ar ² and Ar ³ is a halogen atom or an alkyl group Or it may be substituted with an aryl group.)
^{(4) -Ar 11 -Z-Ar} 12 -
(In the formula, Ar ¹¹ and Ar ¹² each independently represent a phenylene group or a naphthylene group, and Z represents O, CO, or SO _2. )

  Here, the structural unit of the formula (1) is a structural unit derived from an aromatic hydroxycarboxylic acid, and examples of the aromatic hydroxycarboxylic acid include p-hydroxybenzoic acid, m-hydroxybenzoic acid, 2-hydroxy- Examples include 6-naphthoic acid, 2-hydroxy-3-naphthoic acid, and 1-hydroxy-4-naphthoic acid.

  Further, the structural unit of the formula (2) is a structural unit derived from an aromatic dicarboxylic acid, and examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and 1,5-naphthalene. Examples thereof include dicarboxylic acid, diphenyl ether-4,4′-dicarboxylic acid, diphenylsulfone-4,4′-dicarboxylic acid, diphenyl ketone-4,4′-dicarboxylic acid and the like.

  Furthermore, the structural unit of the formula (3) is a structural unit derived from an aromatic diol, an aromatic amine having a phenolic hydroxyl group (phenolic hydroxyl group) or an aromatic diamine. Examples of the aromatic diol include hydroquinone, resorcin, 1,2-benzenediol, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, bis (4-hydroxyphenyl) ether, bis- (4-hydroxyphenyl) ketone, bis- (4-hydroxyphenyl) sulfone, etc. can be mentioned.

  Examples of the aromatic amine having a phenolic hydroxyl group include p-aminophenol and m-aminophenol. Examples of the aromatic diamine include 1,4-phenylenediamine and 1,3-phenylenediamine. Can be mentioned.

  In the liquid crystal resin according to the present invention, when the structural unit of the formula (2) is resorcin, 1,2-benzenediol as the aromatic diol, and / or the case where it is isophthalic acid as the aromatic dicarboxylic acid, (3) When the structural unit is resorcin, 1,2-benzenediol as an aromatic diol, and / or an aromatic amine having a phenolic hydroxyl group or a structural unit derived from an aromatic diamine, a solvent It becomes a soluble liquid crystal resin.

  Such solvent solubility means dissolution in a solvent (solvent) at a concentration of 1% by mass or more at a temperature of 50 ° C.

As such a solvent-soluble liquid crystal resin, those containing a structural unit derived from an aromatic amine having a phenolic hydroxyl group and / or an aromatic diamine as the structural unit of the formula (3) are preferable. That is, the structural unit represented by the formula (3) preferably includes a structural unit in which at least one of X and Y is NH, and substantially all of the structural units represented by the formula (3) are represented by the following formula (3 ′): Is more preferable (hereinafter referred to as “formula (3 ′) structural unit”).
(3 ′) — X—Ar ³ —NH—
(In the formula, Ar ³ and X are as defined above.)

  The structural unit of formula (3 ′) is more preferably contained in the range of 40 to 15 mol%, further preferably in the range of 35 to 20 mol%, based on the total of all the structural units. By doing so, the solvent solubility is further improved.

  The structural unit of the formula (1) is in the range of 20 to 70 mol% and more preferably in the range of 25 to 55 mol% with respect to the total of all the structural units. The liquid crystal resin containing the structural unit of the formula (1) at such a molar fraction tends to be more excellent in solubility in a solvent while sufficiently maintaining liquid crystallinity. Furthermore, p-hydroxybenzoic acid and / or 2-hydroxy-6-naphthoic acid is preferable as the aromatic hydroxycarboxylic acid from which the structural unit of formula (1) is derived. From the viewpoint of improving the solvent solubility of the liquid crystal resin and reducing the dielectric loss tangent, 2-hydroxy-6-naphthoic acid is preferred.

  The structural unit of the formula (2) is in the range of 40 to 15 mol% and more preferably in the range of 37.5 to 22.5 mol% with respect to the total of all the structural units. The liquid crystal resin containing the structural unit of the formula (2) at such a mole fraction tends to have more excellent solubility in a solvent while sufficiently maintaining liquid crystallinity. As the aromatic dicarboxylic acid for deriving the structural unit of the formula (2), at least one selected from the group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid is preferable in that it can be easily obtained. Isophthalic acid is preferable from the viewpoint of improving the solvent solubility of the liquid crystal resin, and 2,6-naphthalenedicarboxylic acid is preferable from the viewpoint of lowering the dielectric loss tangent.

In addition, in the point that the obtained liquid crystal resin exhibits a higher degree of liquid crystallinity, the molar fraction of the structural unit of the formula (2) and the structural unit of the formula (3) is expressed by [formula (2) structural unit] / [formula ( 3) Structural unit], a range of 0.9 / 1 to 1 / 0.9 is preferable.
<Method for producing liquid crystal resin>

  As shown in FIG. 1, a production facility 1 used in the method for producing a liquid crystal resin according to the present invention includes a glass reaction vessel 2 for performing an acylation reaction of a raw material M. The reaction vessel 2 has a cylindrical casing 2a, and a charging port 2b is formed upward in the upper portion of the casing 2a. The reaction vessel 2 is provided with a stirrer, a nitrogen gas introducing device, a thermometer, and a reflux condenser (all not shown).

  Further, in the vicinity of the reaction vessel 2 (on the right side in FIG. 1), a glass polymerization vessel 3 for performing a production reaction of the liquid crystal resin P (polymerization reaction of the raw material M) is installed. The polymerization vessel 3 has a cylindrical casing 3a, and a charging port 3b is formed upward in the upper portion of the casing 3a. A discharge port 3c is formed downward in the casing 3a, and a cock 3d is attached to the discharge port 3c so as to be freely opened and closed. Further, a conical inclined surface 3e is formed on the lower inner wall of the casing 3a so as to incline so as to guide the contents in the casing 3a to the discharge port 3c and collect them by its own weight. Further, a jacket 5 is provided on the outer surface of the polymerization vessel 3, and the contents in the polymerization vessel 3 are supplied to the jacket 5 by supplying a heating medium (heating medium) from an external heat source (not shown). Can be heated or cooled.

  When the liquid crystal resin P is industrially produced in the production facility 1, the raw material M to be used is divided into a plurality of lots, and as described below, these lots are subjected to batch polymerization. The liquid crystal resin P is repeatedly manufactured.

  First, the first lot (first lot) is manufactured.

  That is, in the acylation step, the raw material M is acylated in the reaction vessel 2 to be converted into an ester-forming / amide-forming derivative. For this purpose, the raw material M is introduced into the reaction vessel 2 from the introduction port 2b, and the acylation reaction proceeds in the reaction vessel 2. Thus, the method of acylating the raw material M prior to the resin production step described later is preferable in that the operation is simple.

  Here, this ester-forming / amide-forming derivative will be described with examples.

  As an ester-forming / amide-forming derivative of a monomer having a carboxyl group, such as an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid, an acid is used so that the carboxyl group promotes a reaction to form a polyester or polyamide. Form esters with alcohols, ethylene glycol, etc., such as those with highly reactive groups such as chlorides, acid anhydrides, and the like, such that the carboxyl group generates polyester or polyamide by transesterification / amide exchange reaction And the like.

  As an ester-forming / amide-forming derivative of a monomer having a phenolic hydroxyl group, such as an aromatic hydroxycarboxylic acid or aromatic diol, a phenolic hydroxyl group is formed so as to form a polyester or a polyamide by a transesterification reaction. Are those that form esters with carboxylic acids.

  Examples of the amide-forming derivative of a monomer having an amino group, such as an aromatic diamine, include those in which an amino group forms an amide with a carboxylic acid so that a polyamide is formed by an amide exchange reaction. Can be mentioned.

  Among these, in order to more easily produce a liquid crystal resin, it has an aromatic hydroxycarboxylic acid, an aromatic diol, an aromatic amine having a phenolic hydroxyl group, an aromatic amine, a phenolic hydroxyl group and / or an amino group. After acylating the monomer with a fatty acid anhydride to form an ester-forming / amide-forming derivative (acylated product), the acyl group of this acylated product and the carboxyl group of the monomer having a carboxyl group undergo transesterification / amide exchange. A method of producing a liquid crystal resin by polymerization as it occurs is particularly preferred.

  In the acylation, the amount of fatty acid anhydride used is preferably 1 to 1.2 times equivalent, and 1.05 to 1.1 times equivalent to the total of the phenolic hydroxyl group and amino group. And more preferable. If the amount of fatty acid anhydride used is less than 1 equivalent, the acylated product or raw material M tends to sublimate during polymerization and the reaction system tends to be blocked, and if it exceeds 1.2 equivalents, it is obtained. The liquid crystal resin tends to be markedly colored.

  The acylation is preferably performed at 130 to 180 ° C. for 5 minutes to 10 hours, more preferably at 140 to 160 ° C. for 10 minutes to 3 hours.

  The fatty acid anhydride used for the acylation is preferably acetic anhydride, propionic anhydride, butyric anhydride, isobutyric anhydride or a mixture of two or more selected from these, particularly preferably anhydrous, from the viewpoint of price and handleability. Acetic acid.

  In this acylation process, the by-product fatty acids and unreacted fatty acid anhydrides are distilled out of the system by evaporating, etc. in order to shift the equilibrium according to Le Chatelier-Brown's law (equilibrium transfer principle). It is preferable to do.

  Note that the acylation step and the resin production step may be performed in the presence of a catalyst. As such a catalyst, those conventionally known as polyester polymerization catalysts can be used, such as magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate, antimony trioxide and the like. And organic compound catalysts such as N, N-dimethylaminopyridine and N-methylimidazole.

  However, since a catalyst containing a metal greatly affects electrical characteristics, among the above catalysts, a heterocyclic compound containing two or more nitrogen atoms such as N, N-dimethylaminopyridine and N-methylimidazole is preferably used. (For example, refer to JP 2002-146003 A).

  This catalyst is usually added together when the raw material M is charged, and it is not always necessary to remove it after acylation. If the catalyst is not removed, the process may proceed directly from the acylation step to the resin production step. it can.

  When the raw material M is acylated in this way, the process proceeds to a resin production step, and in the polymerization vessel 3, the raw material M is melt polymerized to produce the liquid crystal resin P. For this purpose, with the cock 3d of the polymerization vessel 3 closed, the raw material M in the reaction vessel 2 is introduced into the polymerization vessel 3 from its inlet 3b, and the melt polymerization reaction proceeds in the polymerization vessel 3. In this resin production | generation process, it is preferable to carry out heating at a rate of 0.1 to 50 ° C./min at 130 to 400 ° C., and at a rate of 0.3 to 5 ° C./min at 150 to 350 ° C. More preferably.

  When the liquid crystal resin P is thus generated, the process proceeds to a resin discharge process, and the liquid crystal resin P is discharged from the polymerization container 3 in the polymerization container 3. For this purpose, with the cock 3d of the polymerization vessel 3 closed, the inside of the polymerization vessel 3 is usually 0.01 MPa or higher (preferably 0.03 MPa or higher) and 0.2 MPa or lower gauge pressure (for example, 0.05 MPa gauge). Pressure), the cock 3d of the polymerization vessel 3 is opened. Then, since the inside of the polymerization container 3 is released from the high pressure state to the atmosphere at once, the liquid crystal resin P in the polymerization container 3 is discharged from the discharge port 3c. Then, when the discharge operation of the liquid crystal resin P is interrupted, the cock 3d of the polymerization vessel 3 is closed. At this time, since the liquid crystal resin P has a predetermined viscosity, a part of the liquid crystal resin P remains in the casing 3 a of the polymerization vessel 3 in a form of adhering to the inclined surface 3 e of the polymerization vessel 3.

  Thus, when most of the liquid crystal resin P is discharged from the polymerization container 3, the process proceeds to the resin re-discharge process. In the polymerization container 3, the liquid crystal resin P remaining in the casing 3a exceeds 0.005 MPa and is usually 0. Re-discharge from the polymerization vessel 3 at a gauge pressure of 2 MPa or less (preferably a gauge pressure of 0.007 MPa or more and 0.2 MPa or less). For this purpose, the inside of the polymerization vessel 3 is pressurized to a gauge pressure of more than 0.005 MPa and 0.2 MPa or less (for example, a gauge pressure of 0.01 MPa) with the cock 3d of the polymerization vessel 3 closed. The cock 3d of the polymerization vessel 3 is opened. Then, since the inside of the polymerization container 3 is released from the high pressure state to the atmosphere at once, the liquid crystal resin P remaining in the casing 3a is discharged from the discharge port 3c.

  At this time, by the discharge pressure (gauge pressure exceeding 0.005 MPa) in this resin re-discharge step, the polymerization is performed so that most of the liquid crystal resin P remaining in the molten state in the polymerization vessel 3 is swept before solidification. The liquid can be discharged from the discharge port 3 c of the container 3. Therefore, it is possible to avoid a situation in which the liquid crystal resin P remaining in the polymerization container 3 is solidified and the discharge port 3c of the polymerization container 3 is blocked.

  As described above, when the discharge pressure in the resin re-discharge process exceeds 0.005 MPa (gauge pressure), as shown in FIG. 2 (a), the liquid crystal resin P is melted immediately before the resin re-discharge process. Even if it remains in the vicinity of the discharge port 3c of the polymerization vessel 3 in the state, immediately after the resin re-discharge process, the liquid crystal resin P is inclined to the inclined surface 3e by a high discharge pressure as shown in FIG. It can be inferred that this is because the fluid can be extruded from the discharge port 3c of the polymerization vessel 3 along the flow line.

  On the other hand, when the discharge pressure in the resin re-discharge process is 0.005 MPa (gauge pressure) or less, as shown in FIG. 3A, the liquid crystal resin P is in a molten state immediately before the resin re-discharge process. If it remains in the vicinity of the discharge port 3c of the polymerization vessel 3, even immediately after the resin re-discharge step, as shown in FIG. 3B, the liquid crystal resin P is discharged to the discharge port 3c of the polymerization vessel 3 by the discharge pressure. Therefore, the liquid crystal resin P remaining in the polymerization vessel 3 may be solidified at a temperature lower than the glass transition temperature as it is, and the discharge port 3c of the polymerization vessel 3 may be blocked.

  Here, the production of the first lot is completed.

  Subsequently, in order to manufacture the next lot (second lot), an acylation process, a resin generation process, a resin discharge process, and a resin re-discharge process are sequentially performed in the same procedure as the manufacture of the first lot. Also at this time, the occurrence of a situation where the liquid crystal resin P remaining in the polymerization container 3 is solidified and the discharge port 3c of the polymerization container 3 is blocked can be avoided as in the case of manufacturing the first lot.

  Thereafter, the third and subsequent lots are manufactured in the same manner, and the manufacturing process of the liquid crystal resin P is completed when the final lot is manufactured.

  Thus, in the manufacturing method of the liquid crystal resin P described above, the resin re-discharge process is incorporated after the resin discharge process for each lot and before the resin generation process for the next lot of the lot. It is possible to avoid a situation in which the three discharge ports 3c are blocked by the liquid crystal resin P. Therefore, even when the liquid crystal resin P has a glass transition temperature, the liquid crystal resin P can be industrially efficiently produced by a batch polymerization method.

As described above, only the reaction vessel 2 is used in the acylation step, and only the polymerization vessel 3 is used in the resin production step, the resin discharge step, and the resin re-discharge step. While performing the discharge process and the resin re-discharge process, the acylation process of the next lot is also performed. By doing so, the idle time in the reaction vessel 2 and the polymerization vessel 3 constituting the production facility 1 can be shortened as much as possible, and the production of the liquid crystal resin P through all lots can be efficiently performed in a short time.
[Other Embodiments of the Invention]

  In the first embodiment described above, the method for producing the liquid crystal resin P in which the acylation process is incorporated before the resin production process has been described. However, depending on the type of the raw material M to be used, this acylation process may be omitted. Is also possible.

Examples of the present invention will be described below. In addition, this invention is not limited to an Example.
<Example 1>

  First, the first lot was manufactured.

  That is, in the acylation step, a reaction vessel equipped with a stirrer, a nitrogen gas introducing device, a thermometer and a reflux condenser was charged with 35 mol% 2-hydroxy-6-naphthoic acid, 32.5 mol% 4-hydroxyacetanilide and isophthalic acid. 32.5 mol% of acid was charged as a raw material, and acetic anhydride was charged as a fatty acid anhydride for acylating these raw materials. The acetic anhydride content was 1.1 times equivalent to the total of phenolic hydroxyl groups and amine groups of 2-hydroxy-6-naphthoic acid and 4-hydroxyacetanilide. Then, after sufficiently replacing the reaction vessel with nitrogen gas, the temperature was raised to 145 ° C. over 30 minutes under a nitrogen gas stream, and the temperature (145 ° C.) was maintained and refluxed for 3 hours.

  Thereafter, in the resin production step, the contents were transferred to a polymerization vessel, and the temperature was raised to 290 ° C. while distilling off by-product acetic acid and unreacted acetic anhydride.

  Next, in the resin discharge step, the liquid crystal resin was discharged from the polymerization vessel at a gauge pressure of 0.05 MPa.

  Finally, in the resin re-discharge process, the discharge port of the polymerization vessel was once closed, the inside of the polymerization vessel was pressurized with a gauge pressure of 0.01 MPa, and the liquid crystal resin remaining in the molten state in the polymerization vessel was discharged.

  Then, the polymerization container was returned to atmospheric pressure, and the adhesion state of the liquid crystal resin was visually confirmed at the discharge port of the polymerization container, and it was found that the discharge port of the polymerization container was not blocked by the liquid crystal resin.

  Subsequently, the second lot was manufactured, and after the temperature of the polymerization vessel was cooled to 150 ° C. by flowing water through the jacket, the second lot was manufactured in the same procedure as the first lot described above. . And also in this 2nd lot, it turned out that the discharge port of the superposition | polymerization container is not obstruct | occluded with liquid crystal resin.

Subsequently, after moving to the third lot and flowing the water through the jacket, the temperature of the polymerization vessel was cooled to 150 ° C., and then the third lot was manufactured in the same procedure as the first lot described above. . However, in the third lot, the scale was 1.6 times that of the first lot. And also in this 3rd lot, it turned out that the discharge port of the superposition | polymerization container is not obstruct | occluded with liquid crystal resin.
<Comparative Example 1>

  The first lot was manufactured in the same manner as in Example 1 described above except that the discharge pressure in the resin re-discharge process was changed from 0.01 MPa (gauge pressure) to 0.005 MPa (gauge pressure).

  That is, in the acylation step, a reaction vessel equipped with a stirrer, a nitrogen gas introducing device, a thermometer and a reflux condenser was charged with 35 mol% 2-hydroxy-6-naphthoic acid, 32.5 mol% 4-hydroxyacetanilide and isophthalic acid. 32.5 mol% of acid was charged as a raw material, and acetic anhydride was charged as a fatty acid anhydride for acylating these raw materials. The acetic anhydride content was 1.1 times equivalent to the total of phenolic hydroxyl groups and amine groups of 2-hydroxy-6-naphthoic acid and 4-hydroxyacetanilide. Then, after sufficiently replacing the reaction vessel with nitrogen gas, the temperature was raised to 145 ° C. over 30 minutes under a nitrogen gas stream, and the temperature (145 ° C.) was maintained and refluxed for 3 hours.

  Thereafter, in the resin production step, the contents were transferred to a polymerization vessel, and the temperature was raised to 290 ° C. while distilling off by-product acetic acid and unreacted acetic anhydride.

  Next, in the resin discharge step, the liquid crystal resin was discharged from the polymerization vessel at a gauge pressure of 0.05 MPa.

  Finally, in the resin re-discharge process, the discharge port of the polymerization vessel was once closed, the inside of the polymerization vessel was pressurized with a gauge pressure of 0.005 MPa, and the liquid crystal resin remaining in the molten state in the polymerization vessel was discharged.

Then, the polymerization container was returned to atmospheric pressure, and the state of adhesion of the liquid crystal resin was confirmed at the discharge port of the polymerization container. As a result, it was found that the discharge port of the polymerization container was blocked by the liquid crystal resin. Therefore, the second and subsequent lots could not be repeatedly manufactured.
<Measurement of glass transition temperature of liquid crystal resin>

  The glass transition temperatures of the liquid crystal resins obtained in Example 1 and Comparative Example 1 were measured. That is, using an analytical differential scanning calorimetry system “DSC6200” manufactured by Seiko Instruments Inc., a calorimetric profile obtained at a heating rate of 10 ° C./min was measured to obtain an endothermic curve. The lowest temperature of the endothermic peak in the endothermic curve thus obtained was taken as the melting point, and the temperature at the inflection point in the endothermic curve appearing on the lower temperature side than this melting point was taken as the glass transition temperature.

  As a result, it was confirmed that all of the liquid crystal resins obtained in Example 1 and Comparative Example 1 had a glass transition temperature in the range of 130 to 135 ° C.

  The present invention can be widely applied to the production of a liquid crystal resin used as a material for an insulating resin base material on a substrate such as a printed wiring board or a package substrate.

DESCRIPTION OF SYMBOLS 1 ... Manufacturing equipment 2 ... Reaction container 2a ... Casing 2b ... Input port 3 ... Polymerization container 3a ... Casing 3b ... Input port 3c ... Discharge port 3d ... Cock 3e ... Inclined surface 5 ... Jacket P …… Liquid crystal resin M …… Raw material

Claims (5)

A resin production process for producing a liquid crystal resin by melt polymerization of raw materials in a polymerization container and a resin ejection process for discharging the liquid crystal resin produced in the resin production process from the polymerization container are repeated for a plurality of lots. A liquid crystal resin manufacturing method to be executed,
After the resin discharge step for each lot and before the resin generation step for the next lot, the liquid crystal resin remaining in the molten state at the discharge port of the polymerization vessel is measured at a gauge pressure exceeding 0.005 MPa. A method for producing a liquid crystal resin, wherein a resin re-discharge process for re-discharge from the polymerization container is incorporated.   The method for producing a liquid crystal resin according to claim 1, wherein the liquid crystal resin is a liquid crystal resin having a glass transition temperature in a range of 50 to 200 ° C.   The liquid crystal resin contains at least one monomer unit selected from the group consisting of a monomer unit having a 1,3-phenylene skeleton, a monomer unit having a 2,3-phenylene skeleton, and a monomer unit having a 2,3-naphthalene skeleton. The method for producing a liquid crystal resin according to claim 1, wherein the liquid crystal resin is contained in a proportion of 10 to 45 mol% with respect to the structural unit. The liquid crystal resin has structural units represented by the following formulas (1), (2), and (3), and the content of the structural unit represented by the formula (1) is the total of all the structural units. The liquid crystal resin has a content of 20 to 70 mol%, a content of the structural unit represented by the formula (2) of 40 to 15 mol%, and a content of the structural unit represented by the formula (3) of 40 to 15 mol%. The method for producing a liquid crystal resin according to any one of claims 1 to 3.
(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
⁽³⁾ -X-Ar 3 -Y-
(In the formula, Ar ¹ represents a phenylene group or a naphthylene group, Ar ² represents a phenylene group, a naphthylene group, or a group represented by the following formula (4), and Ar ³ represents a phenylene group or the following formula (4). X and Y each independently represents O or NH, wherein the hydrogen atom bonded to the aromatic ring of Ar ¹ , Ar ² and Ar ³ is a halogen atom or an alkyl group Or it may be substituted with an aryl group.)
^{(4) -Ar 11 -Z-Ar} 12 -
(In the formula, Ar ¹¹ and Ar ¹² each independently represent a phenylene group or a naphthylene group, and Z represents O, CO, or SO _2. )   The method for producing a liquid crystal resin according to claim 4, wherein at least one of X and Y of the structural unit represented by the formula (3) is NH.