Resin composition and molded article

Abstract

A resin composition and a molded article containing the resin composition, the resin composition containing: a polyimide resin (A) containing a repeating structural unit represented by formula (1) and a repeating structural unit represented by formula (2), the content ratio of the repeating structural unit of formula (1) to the total of the repeating structural unit of formula (1) and the repeating structural unit of formula (2) is 20-70 mol%; and a resin represented by a predetermined formula (5) or an acid-modified product (B) thereof. The ratio [(B) / {(A) + (B)}] of the content mass of the component (B) to the total content mass of the component (A) and the component (B) is 0.50 or less. (In the formula, R1 represents a divalent group having 6-22 carbon atoms and containing at least one alicyclic hydrocarbon structure. And R2 is a divalent chain aliphatic group having 5-16 carbon atoms. And each of X1 and X2 independently represents a tetravalent group having 6-22 carbon atoms and containing at least one aromatic ring. > # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a resin composition and a molded article. Background Art

[0002] Polyimide resins are useful engineering plastics having high heat stability, high strength, and high solvent resistance due to the rigidity of the molecular chain, resonance stabilization, and strong chemical bonding, and are applied to a wide range of fields.

[0003] Polyimide resins have high heat resistance. On the other hand, there is a problem that they do not exhibit thermoplasticity and have low moldability. In recent years, however, polyimide resins having thermoplasticity have been reported. Thermoplastic polyimide resins have excellent moldability in addition to the heat resistance inherent in polyimide resins. Therefore, thermoplastic polyimide resins can also be applied to molded articles used in harsh environments where nylons and polyesters, which are general thermoplastic resins, cannot be used.

[0004] It is also known that polyimide resins exhibit low dielectric constant and low dielectric loss tangent (hereinafter, these are also collectively referred to as "low dielectric properties"). For example, Patent Document 1 discloses a film having low dielectric properties formed of a thermoplastic polyimide resin, and describes that the film can be applied to high-frequency circuit boards, copper-clad laminates, and the like.

[0005] In addition, Patent Document 2 discloses that a resin composition containing a specified liquid crystal polymer and a specific crystalline thermoplastic polyimide resin has excellent melt processability, is easy to melt-knead and extrude, and can achieve both low dielectric constant and low dielectric loss tangent.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: International Publication No. 2022 / 202150

[0009] Patent Document 2: International Publication No. 2022 / 004471 Summary of the Invention

[0010] Problems to be Solved by the Invention

[0011] In recent years, the demand for low dielectric materials as components related to the fifth-generation mobile communication system (5G) and the sixth-generation mobile communication system (6G) has increased, and from the viewpoint of obtaining high electrical properties, further reduction of the dielectric constant and dielectric loss tangent is also desired in organic materials. However, in a thermoplastic resin composition in which a thermoplastic polyimide and other low dielectric resins are used in combination as in the disclosed technique of Patent Document 2, even if a molded article can be produced by injection molding, the moldability in film forming by an extrusion method is low, and it is sometimes difficult to produce a film having a good appearance.

[0012] An object of the present invention is to provide a resin composition having excellent low dielectric properties and good thin film formability, and a molded body containing the resin composition.

[0013] Means for solving the problem

[0014] The present inventors have found that the above problems can be solved by a resin composition containing a polyimide resin and an aromatic resin having a specific structure in a specific ratio, the polyimide resin being composed of specific different polyimide structural units combined in a specific ratio.

[0015] That is, the present invention relates to the following.

[0016] [1] A resin composition containing: a polyimide resin (A) containing a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), and the content ratio of the repeating structural unit of the formula (1) to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 20 to 70 mol%; and a resin represented by the following formula (5) or its acid-modified product (B), and the proportion [(B) / {(A)+(B)}] of the content mass of the foregoing component (B) to the total content mass of the foregoing component (A) and the foregoing component (B) is 0.50 or less.

[0017]

[0018] (R1 is a divalent group having 6 to 22 carbon atoms containing at least 1 alicyclic hydrocarbon structure, R2 is a divalent linear aliphatic group having 5 to 16 carbon atoms, and X1 and X2 are each independently a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring.)

[0019]

[0020] (R 51 ~R 55 and R 61 ~R 64 are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 4 carbon atoms, and R 65 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is the number of repeating structural units and is a number of 10 or more.)

[0021] [2] The resin composition according to the above [1], wherein the total content of the foregoing component (A) and the foregoing component (B) in the resin composition is 50% by mass or more.

[0022] [3] The resin composition according to the above [1] or [2], wherein the intrinsic viscosity of the foregoing component (B) measured in chloroform at 30 ° C is 0.20 to 0.60 dL / g.

[0023] [4] The resin composition according to any one of [1] to [3] above, wherein the resin composition is obtained by melt-kneading at a temperature higher than the melting point of the component (A).

[0024] [5] The resin composition according to any one of [1] to [4] above, wherein the pellets formed from the resin composition have a microphase-separated structure.

[0025] [6] The resin composition according to any one of [1] to [5] above, having a dielectric constant of 3.0 or less and a dielectric loss tangent of 0.005 or less at a measurement frequency of 10 GHz.

[0026] [7] The resin composition according to any one of [1] to [6] above, wherein the absolute value of the coefficient of linear thermal expansion of the molded article obtained by molding the resin composition in the temperature range of 23°C to 210°C measured according to JIS K7197:2012 is 100 ppm / °C or less.

[0027] [8] A molded article comprising the resin composition according to any one of [1] to [7] above.

[0028] [9] The molded article according to [8] above, wherein the molded article is a thin film.

[0029] Effects of the Invention

[0030] According to the present invention, it is possible to provide a resin composition having excellent low dielectric properties and good thin film formability, and a molded article containing the resin composition. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic diagram showing a method for producing a specimen (ultrathin section) used in field emission scanning transmission electron microscope (FE-STEM) observation.

[0032] Figure 2 is a micrograph of a cross-section cut in a direction orthogonal to the flow direction (MD) of the resin composition (pellets) of Example 5 observed by FE-STEM. DETAILED DESCRIPTION

[0033] [Resin Composition]

[0034] The resin composition of the present invention contains: a polyimide resin (A) which comprises a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), and the content ratio of the repeating structural unit of the formula (1) relative to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 20 to 70 mol%; and a resin represented by the following formula (5) or its acid-modified product (B), and the ratio of the content mass of the foregoing component (B) relative to the total content mass of the foregoing component (A) and the foregoing component (B) [(B) / {(A)+(B)}] is 0.50 or less.

[0035]

[0036] (R1 is a divalent group having 6 to 22 carbon atoms containing at least one alicyclic hydrocarbon structure, R2 is a divalent linear aliphatic group having 5 to 16 carbon atoms, and X1 and X2 are each independently a tetravalent group having 6 to 22 carbon atoms containing at least one aromatic ring.)

[0037]

[0038] (R 51 ~R 55 and R 61 ~R 64 are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 4 carbon atoms, and R 65 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is the number of repeating structural units and is a number of 10 or more.)

[0039] The resin composition of the present invention becomes a resin composition having excellent low dielectric properties and good film formability by containing a polyimide resin (A) in which specific different polyimide structural units are combined at the above specific ratio and the resin represented by the foregoing formula (5) or its acid-modified product (B).

[0040] The reason for obtaining the above effects in the present invention is not clear yet, but it is considered as follows.

[0041] Both component (A) and component (B) are thermoplastic resins having low dielectric properties. Component (A) is a crystalline thermoplastic resin, and component (B) is an amorphous thermoplastic resin. By using component (A) and component (B), a resin composition having excellent low dielectric properties can be obtained.

[0042] However, generally, it is difficult to compatibilize a crystalline thermoplastic resin and an amorphous thermoplastic resin. Even if a resin composition obtained by mixing them can be used to produce a molded body by injection molding, its formability in film forming by the extrusion method is low, and it is sometimes difficult to produce a film having a good appearance.

[0043] In the present invention, by using the component (A) having excellent formability as a crystalline thermoplastic resin and using the component (A) and the component (B) in a specific ratio, the component (A) and the component (B) can form a micro-dispersed structure (micro-phase separation structure) in the range of micrometers to nanometers. In particular, by making the above mass ratio [(B) / {(A)+(B)}] 0.50 or less, when the component (A) and the component (B) form a sea-island structure as the micro-phase separation structure, the component (A) is likely to exist on the sea side. As a result, discoloration (ヤケ) and the like due to oxidative degradation of the component (B) are suppressed, and thus it is considered that the film formability based on the extrusion method can be improved while maintaining the low dielectric characteristics.

[0044] In addition, the resin composition of the present invention can be made into a resin composition having high crystallinity derived from the component (A) by making the above mass ratio [(B) / {(A)+(B)}] 0.50 or less. As a result, the obtained resin composition and the formed body are excellent in, for example, reflow soldering resistance. In the present specification, the crystallinity of the resin composition can be judged by taking the heat of fusion as an index.

[0045] Furthermore, according to the resin composition of the present invention, a formed body having a low coefficient of thermal expansion and excellent dimensional stability can be produced.

[0046] <Polyimide resin (A)>

[0047] The polyimide resin (A) used in the present invention contains a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), and the content ratio of the repeating structural unit of the formula (1) with respect to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 20 to 70 mol%.

[0048]

[0049] (R1 is a divalent group having 6 to 22 carbon atoms containing at least 1 alicyclic hydrocarbon structure, R2 is a divalent chain aliphatic group having 5 to 16 carbon atoms, and X1 and X2 are each independently a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring.)

[0050] The polyimide resin (A) used in the present invention is a thermoplastic resin, and as its form, powder or pellets are preferred. The thermoplastic polyimide resin is different from, for example, a polyimide resin formed by closing the imide ring after forming in the state of a polyimide precursor such as polyamic acid and having no glass transition temperature (Tg), or a polyimide resin that decomposes at a temperature lower than the glass transition temperature.

[0051] The repeating structural unit of the formula (1) will be described in detail below.

[0052] R1 is a divalent group having 6 to 22 carbon atoms and containing at least one alicyclic hydrocarbon structure. Here, the alicyclic hydrocarbon structure refers to a ring derived from an alicyclic hydrocarbon compound, which may be saturated or unsaturated, and may be a monocyclic or polycyclic ring.

[0053] Examples of the alicyclic hydrocarbon structure include cycloalkane rings such as cyclohexane ring, cycloalkene rings such as cyclohexene ring, bicycloalkane rings such as norbornane ring, and bicycloalkene rings such as norbornene ring, but are not limited thereto. Among them, cycloalkane rings are preferred, cycloalkane rings having 4 to 7 carbon atoms are more preferred, and cyclohexane ring is further preferred.

[0054] The carbon number of R1 is 6 to 22, preferably 8 to 17.

[0055] R1 contains at least one alicyclic hydrocarbon structure, preferably 1 to 3.

[0056] R1 is preferably a divalent group represented by the following formula (R1-1) or (R1-2).

[0057]

[0058] (m 11 and m 12 are each independently an integer of 0 to 2, preferably 0 or 1, m 13 to m 15 are each independently an integer of 0 to 2, preferably 0 or 1.)

[0059] R1 is particularly preferably a divalent group represented by the following formula (R1-3).

[0060]

[0061] It should be noted that in the divalent group represented by the above formula (R1-3), the positional relationship of the two methylene groups with respect to the cyclohexane ring can be cis or trans, and in addition, the ratio of cis to trans can be any value.

[0062] X1 is a tetravalent group having 6 to 22 carbon atoms and containing at least one aromatic ring. The above aromatic ring can be a monocyclic ring or a fused ring, and examples include benzene ring, naphthalene ring, anthracene ring, and tetracene ring, but are not limited thereto. Among them, benzene ring and naphthalene ring are preferred, and benzene ring is more preferred.

[0063] The carbon number of X1 is 6 to 22, preferably 6 to 18.

[0064] X1 contains at least one aromatic ring, preferably 1 to 3.

[0065] X1 is preferably a tetravalent group represented by any one of the following formulas (X-1) to (X-4).

[0066]

[0067] (R 11 ~R 18 Each independently represents an alkyl group having 1 to 4 carbon atoms. p 11 ~p 13 Each independently represents an integer from 0 to 2, preferably 0. p 14 、p 15 、p 16 and p 18 Each independently represents an integer from 0 to 3, preferably 0. p 17 is an integer from 0 to 4, preferably 0. L 11 ~L 13 Each independently represents a single bond, an ether group, a carbonyl group, or an alkylene group having 1 to 4 carbon atoms.)

[0068] It should be noted that X1 is a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring. Therefore, R in formula (X-2) 12 、R 13 、p 12 and p 13 are selected such that the number of carbon atoms of the tetravalent group represented by formula (X-2) falls within the range of 10 to 22.

[0069] Similarly, L in formula (X-3) 11 、R 14 、R 15 、p 14 and p 15 are selected such that the number of carbon atoms of the tetravalent group represented by formula (X-3) falls within the range of 12 to 22, and L in formula (X-4) 12 、L 13 、R 16 、R 17 、R 18 、p 16 、p 17 and p 18 are selected such that the number of carbon atoms of the tetravalent group represented by formula (X-4) falls within the range of 18 to 22.

[0070] X1 is particularly preferably a tetravalent group represented by the following formula (X-5) or (X-6).

[0071]

[0072] Next, the repeating structural unit of formula (2) will be described in detail.

[0073] R2 is a divalent linear aliphatic group having 5 to 16 carbon atoms, preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and further preferably 8 to 10 carbon atoms. Here, the linear aliphatic group refers to a group derived from a linear aliphatic compound, which may be saturated or unsaturated, may be linear or branched, and may contain heteroatoms such as oxygen atoms.

[0074] R2 is preferably an alkylene group having 5 to 16 carbon atoms, more preferably an alkylene group having 6 to 14 carbon atoms, further preferably an alkylene group having 7 to 12 carbon atoms, and particularly preferably an alkylene group having 8 to 10 carbon atoms. The above alkylene group may be a linear alkylene group or a branched alkylene group, and is preferably a linear alkylene group.

[0075] R2 is preferably at least one selected from octamethylene and decamethylene, and particularly preferably octamethylene.

[0076] In addition, as another preferred embodiment of R2, a divalent linear aliphatic group having 5 to 16 carbon atoms containing an ether group can be cited. The number of carbon atoms is preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and further preferably 8 to 10 carbon atoms. Among them, it is preferably a divalent group represented by the following formula (R2-1) or (R2-2).

[0077]

[0078] (m 21 and m 22 are each independently an integer of 1 to 15, preferably 1 to 13, more preferably 1 to 11, and further preferably 1 to 9. m 23 ~m 25 are each independently an integer of 1 to 14, preferably 1 to 12, more preferably 1 to 10, and further preferably 1 to 8.)

[0079] It should be noted that since R2 is a divalent linear aliphatic group having 5 to 16 carbon atoms (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and further preferably 8 to 10 carbon atoms), m 21 and m 22 in the formula (R2-1) are selected in such a way that the number of carbon atoms of the divalent group represented by the formula (R2-1) falls within the range of 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and further preferably 8 to 10 carbon atoms). That is, m 21 +m 22 is 5 to 16 (preferably 6 to 14, more preferably 7 to 12, and further preferably 8 to 10).

[0080] Similarly, m 23 ~m 25The number of carbon atoms of the divalent group represented by the formula (R2-2) is selected so as to fall within the range of 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and still more preferably 8 to 10 carbon atoms). That is, m 23 +m 24 +m 25 is 5 to 16 (preferably 6 to 14 carbon atoms, more preferably 7 to 12 carbon atoms, and still more preferably 8 to 10 carbon atoms).

[0081] X2 is defined in the same manner as X1 in the formula (1), and the preferred manner is also the same.

[0082] The content ratio of the repeating structural unit of the formula (1) to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 20 to 70 mol%. When the content ratio of the repeating structural unit of the formula (1) is within the above range, the polyimide resin can be sufficiently crystallized even in a general injection molding cycle. If the content ratio is less than 20 mol%, the moldability is reduced. If it is higher than 70 mol%, the crystallinity is reduced, and thus the heat resistance is reduced.

[0083] From the viewpoint of exhibiting high crystallinity, the content ratio of the repeating structural unit of the formula (1) to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is preferably 65 mol% or less, more preferably 60 mol% or less, and still more preferably 50 mol% or less.

[0084] Among them, the content ratio of the repeating structural unit of the formula (1) to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is preferably 20 mol% or more and less than 40 mol%. If it is within this range, the crystallinity of the polyimide resin (A) becomes high, and a resin composition having more excellent heat resistance can be obtained.

[0085] From the viewpoint of moldability, the above content ratio is preferably 25 mol% or more, more preferably 30 mol% or more, and still more preferably 32 mol% or more. From the viewpoint of exhibiting high crystallinity, it is still more preferably 35 mol% or less.

[0086] The content ratio of the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) to all the repeating structural units constituting the polyimide resin (A) is preferably 50 to 100 mol%, more preferably 75 to 100 mol%, still more preferably 80 to 100 mol%, and still more preferably 85 to 100 mol%.

[0087] The polyimide resin (A) may further contain a repeating structural unit represented by the following formula (3). In this case, the content ratio of the repeating structural unit of the formula (3) relative to the total of the repeating structural units of the formula (1) and the repeating structural unit of the formula (2) is preferably 25 mol% or less. On the other hand, the lower limit is not particularly limited, and it may be higher than 0 mol%.

[0088] From the viewpoint of improving heat resistance, the above content ratio is preferably 5 mol% or more, more preferably 10 mol% or more. On the other hand, from the viewpoint of maintaining crystallinity, it is preferably 20 mol% or less, more preferably 15 mol% or less.

[0089]

[0090] (R3 is a divalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring. X3 is a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring.)

[0091] R3 is a divalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring. The above aromatic ring may be a monocyclic ring or a fused ring, and examples thereof include a benzene ring, a naphthalene ring, an anthracene ring, and a tetracene ring, but are not limited thereto. Among them, a benzene ring and a naphthalene ring are preferred, and a benzene ring is more preferred.

[0092] The carbon number of R3 is 6 to 22, preferably 6 to 18.

[0093] R3 contains at least 1 aromatic ring, preferably 1 to 3.

[0094] In addition, a monovalent or divalent electron-withdrawing group may be bonded to the above aromatic ring. Examples of the monovalent electron-withdrawing group include a nitro group, a cyano group, a p-toluenesulfonyl group, a halogen, a haloalkyl group, a phenyl group, and an acyl group. Examples of the divalent electron-withdrawing group include, in addition to a fluoroalkylene group (such as -C(CF3)2-, -(CF2) p -(where p is an integer of 1 to 10)) such a fluoroalkylene group, -CO-, -SO2-, -SO-, -CONH-, -COO-, etc.

[0095] R3 is preferably a divalent group represented by the following formula (R3-1) or (R3-2).

[0096]

[0097] (m 31 and m 32 are each independently an integer of 0 to 2, preferably 0 or 1. m 33 and m 34 are each independently an integer of 0 to 2, preferably 0 or 1. R 21 、R 22 and R23 Each independently represents an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, or an alkynyl group having 2 to 4 carbon atoms. p 21 , p 22 and p 23 is an integer from 0 to 4, preferably 0. L 21 is a single bond, an ether group, a carbonyl group, or an alkylene group having 1 to 4 carbon atoms.)

[0098] In addition, R3 is a divalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring, so m in formula (R3-1) 31 , m 32 , R 21 and p 21 are selected such that the number of carbon atoms of the divalent group represented by formula (R3-1) falls within the range of 6 to 22.

[0099] Similarly, L in formula (R3-2) 21 , m 33 , m 34 , R 22 , R 23 , p 22 and p 23 are selected such that the number of carbon atoms of the divalent group represented by formula (R3-2) falls within the range of 12 to 22.

[0100] X3 is defined in the same manner as X1 in formula (1), and the preferred manner is also the same.

[0101] The polyimide resin (A) may further contain a repeating structural unit represented by the following formula (4).

[0102]

[0103] (R4 is a divalent group containing -SO2- or -Si(R x )(R y )O-, and R x and R y each independently represent a linear aliphatic group having 1 to 3 carbon atoms or a phenyl group. X4 is a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring.)

[0104] X4 is defined in the same manner as X1 in formula (1), and the preferred manner is also the same.

[0105] The terminal structure of the polyimide resin (A) is not particularly limited, and preferably has a linear aliphatic group having 5 to 14 carbon atoms at the terminal.

[0106] The chain aliphatic group may be saturated or unsaturated, and may be linear or branched. When the polyimide resin (A) has the above specific group at the terminal, a resin composition excellent in heat aging resistance can be obtained.

[0107] Examples of the saturated chain aliphatic group having 5 to 14 carbon atoms include n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, lauryl, n-tridecyl, n-tetradecyl, isopentyl, neopentyl, 2-methylpentyl, 2-methylhexyl, 2-ethylpentyl, 3-ethylpentyl, isooctyl, 2-ethylhexyl, 3-ethylhexyl, isononyl, 2-ethyloctyl, isodecyl, isododecyl, isotridecyl, isotetradecyl, etc.

[0108] Examples of the unsaturated chain aliphatic group having 5 to 14 carbon atoms include 1-pentenyl, 2-pentenyl, 1-hexenyl, 2-hexenyl, 1-heptenyl, 2-heptenyl, 1-octenyl, 2-octenyl, nonenyl, decenyl, dodecenyl, tridecenyl, tetradecenyl, etc.

[0109] Among them, the above chain aliphatic group is preferably a saturated chain aliphatic group, more preferably a saturated linear chain aliphatic group. Further, from the viewpoint of obtaining heat aging resistance, the above chain aliphatic group preferably has 6 or more carbon atoms, more preferably 7 or more carbon atoms, still more preferably 8 or more carbon atoms, preferably 12 or less carbon atoms, more preferably 10 or less carbon atoms, still more preferably 9 or less carbon atoms. The above chain aliphatic group may be only 1 kind or 2 or more kinds.

[0110] The above chain aliphatic group is particularly preferably at least one selected from the group consisting of n-octyl, isooctyl, 2-ethylhexyl, n-nonyl, isononyl, n-decyl and isodecyl, more preferably at least one selected from the group consisting of n-octyl, isooctyl, 2-ethylhexyl, n-nonyl and isononyl, and most preferably at least one selected from the group consisting of n-octyl, isooctyl and 2-ethylhexyl.

[0111] Further, from the viewpoint of heat aging resistance, the polyimide resin (A) preferably has only a chain aliphatic group having 5 to 14 carbon atoms at the terminal in addition to the terminal amino group and the terminal carboxyl group. When having a group other than the above at the terminal, its content is preferably 10 mol% or less, more preferably 5 mol% or less, relative to the chain aliphatic group having 5 to 14 carbon atoms.

[0112] From the viewpoint of exhibiting excellent heat aging resistance, with respect to a total of 100 mol% of all repeating structural units constituting the polyimide resin (A), the content of the above-mentioned linear aliphatic group having 5 to 14 carbon atoms in the polyimide resin (A) is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, and further preferably 0.2 mol% or more. In addition, in order to ensure a sufficient molecular weight and obtain good mechanical properties, with respect to a total of 100 mol% of all repeating structural units constituting the polyimide resin (A), the content of the above-mentioned linear aliphatic group having 5 to 14 carbon atoms in the polyimide resin (A) is preferably 10 mol% or less, more preferably 6 mol% or less, and further preferably 3.5 mol% or less.

[0113] The content of the above-mentioned linear aliphatic group having 5 to 14 carbon atoms in the polyimide resin (A) can be determined by depolymerizing the polyimide resin (A).

[0114] The polyimide resin (A) preferably has a melting point of 360°C or lower and a glass transition temperature of 150°C or higher. From the viewpoint of heat resistance, the melting point of the polyimide resin (A) is more preferably 280°C or higher, and further preferably 290°C or higher. From the viewpoint of exhibiting high formability, it is preferably 345°C or lower, more preferably 340°C or lower, and further preferably 335°C or lower. In addition, from the viewpoint of heat resistance, the glass transition temperature of the polyimide resin (A) is more preferably 160°C or higher, and more preferably 170°C or higher. From the viewpoint of exhibiting high formability, it is preferably 250°C or lower, more preferably 230°C or lower, and further preferably 200°C or lower.

[0115] The melting point and glass transition temperature of the polyimide resin (A) can both be measured using a differential scanning calorimeter.

[0116] In addition, for the polyimide resin (A), from the viewpoints of improving crystallinity, heat resistance, mechanical strength, and chemical resistance, the heat of the crystallization exothermic peak (hereinafter also simply referred to as "heat of crystallization") observed when the polyimide resin (A) is melted and cooled at a cooling rate of 20°C / minute as measured by a differential scanning calorimeter is preferably 5.0 mJ / mg or more, more preferably 10.0 mJ / mg or more, and further preferably 17.0 mJ / mg or more. The upper limit value of the heat of crystallization is not particularly limited and is usually 45.0 mJ / mg or less.

[0117] Specifically, the melting point, glass transition temperature, and heat of crystallization of the polyimide resin (A) can be measured using the methods described in the examples.

[0118] The logarithmic viscosity of a 0.5 mass% sulfuric acid solution of the polyimide resin (A) at 30 °C is preferably in the range of 0.2 to 2.0 dL / g, more preferably in the range of 0.3 to 1.8 dL / g. If the logarithmic viscosity is 0.2 dL / g or more, sufficient mechanical strength can be obtained when the resulting resin composition is formed into a molded article, and if it is 2.0 dL / g or less, the formability and workability become good. The logarithmic viscosity μ is determined by measuring the flow times of sulfuric acid and the above polyimide resin solution at 30 °C using a Cannon-Fenske viscometer and calculating from the following formula.

[0119] μ = ln(ts / t0) / C

[0120] t0: Flow time of sulfuric acid

[0121] ts: Flow time of polyimide resin solution

[0122] C: 0.5 (g / dL)

[0123] The weight average molecular weight Mw of the polyimide resin (A) is preferably in the range of 10,000 to 150,000, more preferably in the range of 15,000 to 100,000, further preferably in the range of 20,000 to 80,000, still further preferably in the range of 30,000 to 70,000, and even more preferably in the range of 35,000 to 65,000. If the weight average molecular weight Mw of the polyimide resin (A) is 10,000 or more, the mechanical strength of the resulting molded article becomes good, if it is 40,000 or more, the stability of the mechanical strength becomes good, and if it is 150,000 or less, the formability becomes good.

[0124] The weight average molecular weight Mw of the polyimide resin (A) can be measured by gel permeation chromatography (GPC) using polymethyl methacrylate (PMMA) as a standard sample.

[0125] (Method for producing polyimide resin (A))

[0126] The polyimide resin (A) can be produced by reacting a tetracarboxylic acid component with a diamine component. The tetracarboxylic acid component contains a tetracarboxylic acid containing at least 1 aromatic ring and / or its derivative, and the diamine component contains a diamine containing at least 1 alicyclic hydrocarbon structure and a linear aliphatic diamine.

[0127] The tetracarboxylic acid containing at least one aromatic ring is preferably a compound in which 4 carboxyl groups are directly bonded to the aromatic ring, and an alkyl group may be included in the structure. Additionally, the above-mentioned tetracarboxylic acid preferably has 6 to 26 carbon atoms. As the above-mentioned tetracarboxylic acid, pyromellitic acid, 2,3,5,6-toluene tetracarboxylic acid, 3,3',4,4'-benzophenone tetracarboxylic acid, 3,3',4,4'-biphenyl tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, etc. are preferred. Among them, pyromellitic acid is more preferred.

[0128] As derivatives of the tetracarboxylic acid containing at least one aromatic ring, an anhydride or an alkyl ester of the tetracarboxylic acid containing at least one aromatic ring can be cited. The above-mentioned tetracarboxylic acid derivative preferably has 6 to 38 carbon atoms. As the acid anhydride of the tetracarboxylic acid, pyromellitic acid monoanhydride, pyromellitic dianhydride, 2,3,5,6-toluene tetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, etc. can be cited. As the alkyl ester of the tetracarboxylic acid, dimethyl pyromellitate, diethyl pyromellitate, dipropyl pyromellitate, diisopropyl pyromellitate, dimethyl 2,3,5,6-toluene tetracarboxylate, dimethyl 3,3',4,4'-diphenylsulfone tetracarboxylate, dimethyl 3,3',4,4'-benzophenone tetracarboxylate, dimethyl 3,3',4,4'-biphenyl tetracarboxylate, dimethyl 1,4,5,8-naphthalene tetracarboxylate, etc. can be cited. Among the above-mentioned alkyl esters of the tetracarboxylic acid, the alkyl group preferably has 1 to 3 carbon atoms.

[0129] The tetracarboxylic acid containing at least one aromatic ring and / or its derivative can use at least one compound selected from the above alone, or can use two or more compounds in combination.

[0130] The carbon number of the diamine containing at least one alicyclic hydrocarbon structure is preferably 6 to 22. For example, 1,2-bis(aminomethyl)cyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 4,4'-diaminodicyclohexylmethane, 4,4'-methylenebis(2-methylcyclohexylamine), carvone diamine, limonene diamine, isophorone diamine, norbornane diamine, bis(aminomethyl)tricyclo[5.2.1.0 2,6 decane, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, 4,4'-diaminodicyclohexylpropane, etc. can be used. These compounds can be used alone, or two or more of them can be used in combination. Among them, 1,3-bis(aminomethyl)cyclohexane can be preferably used. It should be noted that the diamine containing an alicyclic hydrocarbon structure usually has structural isomers, but the ratio of the cis form to the trans form is not limited.

[0131] The chain aliphatic diamine can be linear or branched, preferably having 5 to 16 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 7 to 12 carbon atoms. Additionally, if the carbon number of the chain portion is 5 to 16, an ether bond may be contained therein. As the chain aliphatic diamine, for example, 1,5-pentamethylenediamine, 2-methylpentane-1,5-diamine, 3-methylpentane-1,5-diamine, 1,6-hexamethylenediamine, 1,7-heptamethylenediamine, 1,8-octamethylenediamine, 1,9-nonamethylenediamine, 1,10-decamethylenediamine, 1,11-undecamethylenediamine, 1,12-dodecamethylenediamine, 1,13-tridecamethylenediamine, 1,14-tetradecamethylenediamine, 1,16-hexadecamethylenediamine, 2,2'-(ethylenedioxy)bis(ethylamine), etc. are preferred.

[0132] One kind or a mixture of multiple kinds of chain aliphatic diamines can be used. Among them, chain aliphatic diamines having 8 to 10 carbon atoms can be preferably used, and in particular, at least one selected from the group consisting of 1,8-octamethylenediamine and 1,10-decamethylenediamine can be preferably used.

[0133] When producing the polyimide resin (A), the input amount of the diamine containing at least one alicyclic hydrocarbon structure is preferably 20 to 70 mol% based on the total molar amount of the diamine containing at least one alicyclic hydrocarbon structure and the chain aliphatic diamine. This molar amount is preferably 25 mol% or more, more preferably 30 mol% or more, even more preferably 32 mol% or more, and from the viewpoint of exhibiting high crystallinity, it is preferably 60 mol% or less, more preferably 50 mol% or less, even more preferably less than 40 mol%, and even more preferably 35 mol% or less.

[0134] In addition, the above diamine component may contain a diamine containing at least one aromatic ring. The carbon number of the diamine containing at least one aromatic ring is preferably 6 to 22, and examples include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 1,2-diethynylbenzene diamine, 1,3-diethynylbenzene diamine, 1,4-diethynylbenzene diamine, 1,2-diaminobenzene, 1,3-diaminobenzene, 1,4-diaminobenzene, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl methane, α,α'-bis(4-aminophenyl)-1,4-diisopropylbenzene, α,α'-bis(3-aminophenyl)-1,4-diisopropylbenzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,6-diaminonaphthalene, 1,5-diaminonaphthalene, etc.

[0135] Among the above, the molar ratio of the input amount of the diamine containing at least 1 aromatic ring to the total amount of the diamine containing at least 1 alicyclic hydrocarbon structure and the linear aliphatic diamine is preferably 25 mol% or less. On the other hand, the lower limit is not particularly limited, and it may be higher than 0 mol%.

[0136] From the viewpoint of improving heat resistance, the above molar ratio is preferably 5 mol% or more, more preferably 10 mol% or more. On the other hand, from the viewpoint of maintaining crystallinity, it is preferably 20 mol% or less, more preferably 15 mol% or less.

[0137] In addition, from the viewpoint of reducing the coloring of the polyimide resin (A), the above molar ratio is preferably 12 mol% or less, more preferably 10 mol% or less, further preferably 5 mol% or less, and even more preferably 0 mol%.

[0138] When producing the polyimide resin (A), regarding the input amount ratio of the above tetracarboxylic acid component and the above diamine component, it is preferable that the diamine component is 0.9 to 1.1 moles relative to 1 mole of the tetracarboxylic acid component.

[0139] In addition, when producing the polyimide resin (A), in addition to the above tetracarboxylic acid component and the above diamine component, a capping agent may be mixed. As the capping agent, at least 1 selected from the group consisting of monoamines and dicarboxylic acids is preferable. The amount of the capping agent used is only required to be an amount capable of introducing a desired amount of end groups into the polyimide resin (A). Relative to 1 mole of the above tetracarboxylic acid and / or its derivative, it is preferably 0.0001 to 0.1 mole, more preferably 0.001 to 0.06 mole, and further preferably 0.002 to 0.035 mole.

[0140] Among them, as the capping agent, a monoamine capping agent is preferable. From the viewpoint of improving heat aging resistance by introducing the above linear aliphatic group having 5 to 14 carbon atoms at the end of the polyimide resin (A), a monoamine having a linear aliphatic group having 5 to 14 carbon atoms is more preferable, and a monoamine having a saturated linear aliphatic group having 5 to 14 carbon atoms is further preferable.

[0141] The capping agent is particularly preferably at least 1 selected from the group consisting of n-octylamine, isooctylamine, 2-ethylhexylamine, n-nonylamine, isononylamine, n-decylamine, and isodecylamine, more preferably at least 1 selected from the group consisting of n-octylamine, isooctylamine, 2-ethylhexylamine, n-nonylamine, and isononylamine, and most preferably at least 1 selected from the group consisting of n-octylamine, isooctylamine, and 2-ethylhexylamine.

[0142] As the polymerization method for producing the polyimide resin (A), a known polymerization method can be applied, and the method described in International Publication No. 2016 / 147996 can be used.

[0143] <The resin represented by the formula (5) or its acid-modified product (B)>

[0144] The resin composition of the present invention contains a polyimide resin (A) and a resin represented by the following formula (5) or its acid-modified product (B).

[0145]

[0146] (R 51 ~R 55 and R 61 ~R 64 are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 4 carbon atoms, and R 65 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is the number of repeating structural units and is a number of 10 or more.)

[0147] In the formula (5), R 51 ~R 55 and R 61 ~R 65 The alkyl group having 1 to 4 carbon atoms in may be either linear or branched, and examples thereof include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl. Among them, methyl, ethyl, n-propyl or isopropyl is preferred, and methyl is more preferred.

[0148] In the formula (5), R 51 、R 53 、R 61 and R 63 are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or methyl, and further preferably a hydrogen atom.

[0149] R 52 、R 54 、R 62 and R 64 are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or methyl, and further preferably methyl.

[0150] R 65 is preferably a hydrogen atom.

[0151] In the formula (5), n is a number of 10 or more, more preferably 20 or more.

[0152] As the resin represented by the above formula (5), a resin represented by the following formula (5-1), that is, poly(2,6-dimethyl-1,4-phenylene ether), is preferred.

[0153]

[0154] (In the formula, n is the same as above.)

[0155] As the acid-modified product of the resin represented by the formula (5), a resin obtained by modifying the resin represented by the formula (5) with a carboxylic acid or a carboxylic acid derivative can be mentioned. From the viewpoint of reactivity with the resin represented by the formula (5), the carboxylic acid or the carboxylic acid derivative is preferably an unsaturated carboxylic acid and its derivative.

[0156] Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, sorbic acid, mesaconic acid, angelic acid, etc. In addition, examples of the derivative of the unsaturated carboxylic acid include acid anhydride, ester, amide, imide, metal salt, etc., and acid anhydride is preferably used.

[0157] Among the above, from the viewpoints of obtaining low dielectric characteristics, improving thin film formability, and availability, the acid-modified product of the resin represented by the formula (5) is preferably a resin obtained by modifying the resin represented by the formula (5) with maleic acid or a maleic acid derivative (maleic acid-modified product of the resin represented by the formula (5)), and more preferably a resin obtained by modifying the resin represented by the formula (5) with maleic anhydride.

[0158] As the maleic acid-modified product of the resin represented by the formula (5), a resin having a structure represented by the following formula (5-2) and / or the following formula (5-3) can be mentioned.

[0159]

[0160] (In the formula, R 51 ~R 55 , R 61 , R 63 , R 64 , R 65 and n are the same as above.)

[0161] From the viewpoints of obtaining low dielectric characteristics, improving thin film formability, and availability, the acid modification rate in the acid-modified product of the resin represented by the formula (5) is preferably 0.01 to 5.0% by mass, more preferably 0.05 to 3.0% by mass, further preferably 0.1 to 2.0% by mass, and still more preferably 0.2 to 1.0% by mass. The acid modification rate here means the content (% by mass) of the structure derived from the acid in the acid-modified product. For example, when the acid-modified product of the resin represented by the formula (5) is a resin obtained by modifying the resin represented by the formula (5) with maleic anhydride, the acid modification rate means the content (% by mass) of the structure derived from maleic anhydride in the acid-modified product.

[0162] From the viewpoints of obtaining low dielectric properties, improving the film formability, and availability, component (B) is preferably the resin represented by the above formula (5) or its maleic acid-modified product, more preferably the resin represented by the above formula (5), and still more preferably the resin represented by the above formula (5-1), namely poly(2,6-dimethyl-1,4-phenylene ether).

[0163] From the viewpoints of obtaining low dielectric properties and improving the film formability, the intrinsic viscosity of component (B) measured in chloroform at 30 °C is preferably 0.20 to 0.60 dL / g, more preferably 0.30 to 0.50 dL / g, and still more preferably 0.30 to 0.45 dL / g.

[0164] As the resin represented by the above formula (5), commercially available products such as "PX100F" (poly(2,6-dimethyl-1,4-phenylene ether), Tg = 207 °C, intrinsic viscosity at 30 °C measured in chloroform = 0.37 dL / g) and "PX100L" (poly(2,6-dimethyl-1,4-phenylene ether), Tg = 210 °C, intrinsic viscosity at 30 °C measured in chloroform = 0.47 dL / g) manufactured by Polyxylenol Singapore Pte Ltd can also be used.

[0165] As commercially available products of the resin (maleic acid-modified product) obtained by modifying the resin represented by the above formula (5) with maleic anhydride, "Iupiace PME-80" (maleic anhydride modification rate 0.38 mass%) manufactured by Mitsubishi Engineering-Plastics Corporation, etc. can be cited.

[0166] <Content>

[0167] From the viewpoint of improving the film formability, the mass ratio of component (B) in the resin composition to the total mass of components (A) and (B) [(B) / {(A)+(B)}] is 0.50 or less, preferably 0.40 or less, more preferably 0.30 or less, still more preferably 0.20 or less, and even more preferably 0.15 or less. In addition, the lower limit is higher than 0, and from the viewpoint of obtaining low dielectric properties, it is preferably 0.005 or more, more preferably 0.01 or more, still more preferably 0.05 or more, and even more preferably 0.10 or more.

[0168] The content of component (A) in the resin composition is not particularly limited as long as the above [(B) / {(A)+(B)}] is 0.50 or less. From the viewpoints of obtaining low dielectric properties and improving film formability, it is preferably 50 to 99.9% by mass, more preferably 60 to 99.5% by mass, further preferably 70 to 99.5% by mass, still further preferably 80 to 99% by mass, still further preferably 80 to 98% by mass, and still further preferably 80 to 95% by mass.

[0169] The content of component (B) in the resin composition is not particularly limited as long as the above [(B) / {(A)+(B)}] is 0.50 or less. From the viewpoints of obtaining low dielectric properties and improving film formability, it is preferably 0.1 to 50% by mass, more preferably 0.5 to 40% by mass, further preferably 0.5 to 30% by mass, still further preferably 1 to 20% by mass, still further preferably 2 to 20% by mass, and still further preferably 5 to 20% by mass.

[0170] <Additive>

[0171] In the resin composition of the present invention, additives such as fillers, reinforcing fibers, matting agents, plasticizers, antistatic agents, anti-coloring agents, anti-gelation agents, coloring agents, sliding property improvers, antioxidants, conductive agents, resin modifiers, compatibilizers, etc. can be compounded as needed.

[0172] When using the above additives, the compounding amount thereof is not particularly limited. From the viewpoints of maintaining low dielectric properties and film formability and exhibiting the effects of the additives, in the resin composition, it is usually 50% by mass or less, preferably 0.0001 to 30% by mass, more preferably 0.001 to 15% by mass, and further preferably 0.01 to 10% by mass.

[0173] In addition, in the resin composition of the present invention, resins other than component (A) and component (B) can be compounded within a range that does not hinder its properties. As such resins, thermoplastic resins with high heat resistance are preferred, and examples thereof include polyamide resins, polyester resins, polyimide resins other than polyimide resin (A), polycarbonate resins, polyetherimide resins, polyamideimide resins, polyphenylene etherimide resins, polyphenylene sulfide resins, polysulfone resins, polyethersulfone resins, polyarylate resins, liquid crystal polymers, polyetheretherketone resins, polyetherketone resins, polyetherketoneketone resins, polyetheretherketoneketone resins, polybenzimidazole resins, fluorine-based resins, etc. As fluorine-based resins, examples include polytetrafluoroethylene, perfluoroalkyl vinyl ether copolymers, tetrafluoroethylene-ethylene copolymers, polyvinylidene fluoride, polytrifluorochloroethylene, etc.

[0174] Among them, from the viewpoints of heat resistance, moldability, strength, and solvent resistance, one or more selected from the group consisting of polyetherimide resin, polyphenylene sulfide resin, and polyether ether ketone resin are preferred. From the viewpoint of low water absorption, a liquid crystal polymer is preferred. From the viewpoint of obtaining high flame retardancy, one or more selected from the group consisting of polyphenylene sulfide resin, polytetrafluoroethylene, and perfluoroalkyl vinyl ether copolymer are preferred.

[0175] When resins other than component (A) and component (B) are used in combination, as long as it is within the range that does not hinder the properties of the resin composition, the compounding amount thereof is not particularly limited.

[0176] However, from the viewpoint of obtaining the effects of the present invention, the total content of component (A) and component (B) in the resin composition of the present invention is preferably 30% by mass or more, more preferably 40% by mass or more, further preferably 50% by mass or more, still further preferably 70% by mass or more, still further preferably 80% by mass or more, still further preferably 90% by mass or more, still further preferably 95% by mass or more, and 100% by mass or less.

[0177] From the viewpoint of forming into pellet form, the resin composition of the present invention preferably does not contain a solvent. Specifically, the content of the solvent in the resin composition is preferably 5% by mass or less, more preferably 1% by mass or less, and further preferably 0.1% by mass or less.

[0178] <Morphology of resin composition>

[0179] The resin composition of the present invention can be in any form. From the viewpoint of obtaining excellent low dielectric properties by forming the microphase separation structure described later, those obtained by melt-kneading at a temperature higher than the melting point of component (A) are preferred, and pellets obtained by melt-kneading at a temperature higher than the melting point of component (A) are more preferred. That is, it is preferred to apply a heat history to component (A) in the resin composition of the present invention, and this resin composition is different from the resin composition containing component (A) in powder form.

[0180] The resin composition of the present invention has thermoplasticity. Therefore, for example, after adding component (A), component (B), and various optional components as needed and performing dry blending, or feeding component (B) and optional components from different parts than the feeding of component (A) into the extruder, melt-kneading in the extruder and extruding a wire, and cutting the wire, pelletization can be performed. In addition, by introducing the pellets into various molding machines and performing thermoforming by the method described later, a molded body having a desired shape can be easily manufactured.

[0181] From the viewpoint of obtaining low dielectric properties, the pellets formed from the resin composition of the present invention and the molded article obtained by molding the resin composition preferably have a microphase separation structure. The microphase separation structure is a micron- to nanometer-scale phase separation structure formed by the phase separation of component (A) and component (B), and can be a sea-island structure or a co-continuous structure, preferably a sea-island structure. In the sea-island structure, depending on the mass ratio of component (A) and component (B) in the pellets, either component can form the "sea", but from the viewpoint of obtaining excellent film formability, it is preferred that component (A) forms the "sea".

[0182] Regarding whether the pellets or the molded article has a microphase separation structure, it can be determined by observing the surface or cross-section of the pellets or the molded article with a scanning transmission electron microscope (STEM).

[0183] From the viewpoints of improving crystallinity, improving film formability, and improving the reflow soldering resistance of the obtained molded article, etc., the heat of fusion (Hm) of the resin composition of the present invention is preferably 10 mJ / mg or more, more preferably 12 mJ / mg or more, further preferably 15 mJ / mg or more, and even more preferably 18 mJ / mg or more. The upper limit is not particularly limited and is usually 45.0 mJ / mg or less.

[0184] Specifically, the heat of fusion (Hm) can be measured by the method described in the examples.

[0185] [Molded article]

[0186] The present invention provides a molded article containing the above resin composition. The shape of the molded article is not particularly limited, and examples include sheets, films, wires, filaments, etc. They can be intermediate members of industrial products or final products.

[0187] From the viewpoint of effectively exerting the effects of the present invention, the molded article of the present invention is preferably a film. The thickness of the film is not particularly limited. As the thickness of the film produced by the extrusion molding method, it is usually 500 μm or less, preferably 200 μm or less, more preferably less than 100 μm, further preferably 80 μm or less, and even more preferably 60 μm or less. The lower limit of the film thickness is usually 5 μm or more, preferably 10 μm or more.

[0188] In this specification, the "thickness of the film" refers to the average value of the thickness of the film. In addition, in the molded article in the form of a film, in addition to the form of the resin film, it also includes the form of the resin layer constituting the multi-layer laminate and the form of the coating, etc.

[0189] The resin composition of the present invention is thermoplastic, and thus the molded article of the present invention can be easily manufactured by thermoforming. Examples of the thermoforming method include injection molding, extrusion molding, blow molding, blow extrusion molding, hot pressing molding, vacuum molding, pressure air molding, laser molding, welding, fusion welding, etc. Any method can be used for molding as long as it is a molding method that includes a hot melting process.

[0190] When manufacturing a molded article in the form of a film, extrusion molding is preferred. For example, it can be molded within a temperature range of 290 °C or higher and 400 °C or lower, preferably 290 °C or higher and 360 °C or lower.

[0191] As a method for manufacturing a molded article, for example, the following method can be cited: after drying the pellets produced by the above method, the pellets are introduced into various molding machines for thermoforming to manufacture a molded article having a desired shape.

[0192] <Low dielectric properties>

[0193] The resin composition and the molded article of the present invention have low dielectric properties. For example, a dielectric constant of 3.0 or less and a dielectric loss tangent of 0.005 or less can be achieved at a measurement frequency of 10 GHz. The dielectric constant is preferably 2.90 or less, more preferably 2.85 or less, further preferably 2.70 or less, still further preferably 2.50 or less, still further preferably 2.40 or less, and the dielectric loss tangent is preferably 0.004 or less, more preferably 0.003 or less. Specifically, the dielectric constant and the dielectric loss tangent can be measured by the method described in the examples.

[0194] <Coefficient of thermal expansion (CTE)>

[0195] The resin composition and the molded article of the present invention exhibit low CTE. For example, the absolute value of the coefficient of thermal expansion in the temperature range of 23 °C to 210 °C measured according to JIS K7197:2012 of the molded article formed from the resin composition is preferably 100 ppm / °C or less, more preferably 90 ppm / °C or less, further preferably 85 ppm / °C or less, still further preferably 80 ppm / °C or less, still further preferably 75 ppm / °C or less, still further preferably 70 ppm / °C or less.

[0196] It should be noted that for a molded article that has been stretched, the value of CTE changes. Therefore, the molded article used for CTE measurement is preferably an unstretched molded article, and more preferably an injection molded article.

[0197] In an injection molded article, there are also a flow direction (MD) and a direction (TD) orthogonal thereto, and sometimes the CTEs in the MD and TD are different. In this case, it is preferable that the average of the absolute values of the coefficient of thermal expansion in the MD and TD is within the above range. Here, the average of the absolute values of the coefficient of thermal expansion in the MD and TD means {(absolute value of the coefficient of thermal expansion in the MD) + (absolute value of the coefficient of thermal expansion in the TD)} / 2.

[0198] Furthermore, from the viewpoint of dimensional stability, the absolute value of the coefficient of thermal expansion in at least one of the MD or TD, preferably the absolute value of the coefficient of thermal expansion in the MD, is preferably 55 ppm / °C or less, more preferably 50 ppm / °C or less.

[0199] The coefficient of thermal expansion of the molded article is a value measured in a compression mode by thermomechanical analysis (TMA method), and specifically, it can be measured by the method described in the examples.

[0200] <Use>

[0201] The resin composition and the molded article of the present invention are preferably used for applications requiring a low dielectric constant and a low dielectric loss tangent, and can be applied to, for example, 5G, or components related to the sixth-generation mobile communication system (6G) using a frequency band of 70G to 300GHz (smartphones, flexible printed circuit boards, metal foil laminates such as copper-clad laminates, antennas, antenna substrates, etc.), various antennas other than the above (microwave antennas, millimeter-wave antennas, waveguide slot antennas, horn antennas, lens antennas, printed antennas, triplate antennas, microstrip antennas, patch antennas, etc.), various antenna substrates (antenna substrates for 77GHz automotive millimeter-wave radars, antenna substrates for terahertz radars, antenna substrates for aircraft radars, antenna substrates for tracked special vehicles, antenna substrates for WiGig, etc.), wire coating materials (low-dielectric wire coating materials, etc.), bonding sheets, insulating films, raw materials for carbon fiber reinforced plastics (CFRP), high-frequency circuit boards, printed wiring boards, chip-on-film (COF) flexible substrates, multi-layer laminates, LED-mounted substrates, industrial robot substrates, communication substrates for household robots, semiconductor element materials, wafers for high-frequency devices, Wi-fi chips, wireless communication devices, transmission lines (coaxial lines, strip lines, microstrip lines, coplanar lines, parallel lines, etc.), coatings for bearings, heat-insulating shafts, trays, various belts (seamless belts, etc.), heat-resistant low-dielectric belts, heat-resistant low-dielectric tubes, various sensors (contact sensors, etc.), various radars (automotive radars, aerospace radars, etc.), radomes, optical communication modules (TOSA / ROSA), cable mobile terminals or digital home appliances for 8k-TV (tablet terminals, notebook PCs, thin TVs, roll-up TVs, digital cameras, smart glasses, smart watches, etc.), base stations (macro cell base stations, small cell base stations, C-RAN base stations, etc.), unmanned aerial vehicles (commercial unmanned aerial vehicles, long-distance mobile unmanned aerial vehicles, etc.), surveillance cameras, indoor or outdoor servers, artificial satellites, communication equipment for space stations, etc.

[0202] Examples

[0203] Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In addition, various measurements and evaluations in each production example and example are carried out as follows.

[0204] <Infrared spectroscopic analysis (IR measurement)>

[0205] The IR measurement of the polyimide resin was carried out using "JIR-WINSPEC50" manufactured by JEOL Ltd.

[0206] <Logarithmic viscosity μ>

[0207] After drying the polyimide resin at 190 to 200 °C for 2 hours, a polyimide resin solution obtained by dissolving 0.100 g of the polyimide resin in 20 mL of concentrated sulfuric acid (96%, manufactured by Kanto Chemical Co., Inc.) was used as a measurement sample, and the measurement was carried out at 30 °C using a Cannon-Fenske viscometer. The logarithmic viscosity μ was calculated by the following formula.

[0208] μ = ln[(ts / t0) / C]

[0209] t0: Flow time of concentrated sulfuric acid

[0210] ts: Flow time of the polyimide resin solution

[0211] C: 0.5 g / dL

[0212] <Melting point, glass transition temperature, crystallization temperature, heat of fusion, heat of crystallization>

[0213] The melting point Tm, glass transition temperature Tg, crystallization temperature Tc, heat of fusion Hm, and heat of crystallization Hc of the resin used in each example alone or the resin composition obtained in each example were measured using a differential scanning calorimeter device ("DSC-25" manufactured by TA Instruments). In the measurement of the crystallization temperature Tc, resin powder was used for the polyimide resin, and pellets were used as the measurement sample for the crystalline thermoplastic resin composition.

[0214] Under a nitrogen atmosphere, a heat history under the following conditions was applied to the measurement sample. The conditions of the heat history were the first heating (heating rate: 10 °C / min), subsequent cooling (cooling rate: 20 °C / min), and subsequent second heating (heating rate: 10 °C / min).

[0215] Regarding the melting point Tm, it was determined by reading the peak top value of the endothermic peak observed during the second heating. The glass transition temperature Tg was determined by reading the value observed during the second heating. The crystallization temperature Tc was determined by reading the peak top value of the exothermic peak observed during cooling. It should be noted that regarding Tm, Tg, and Tc, in the case where multiple peaks were observed, the peak top values of each peak were read.

[0216] The heat of fusion Hm (mJ / mg) was calculated from the area of the heat of fusion peak (endothermic peak) near the melting point observed when the measurement sample was heated to a temperature above the melting point at a heating rate of 10 °C / min to melt it, then cooled at a cooling rate of 20 °C / min, and melted again at a heating rate of 10 °C / min. In addition, the heat of crystallization Hc (mJ / mg) was calculated from the area of the crystallization exothermic peak observed when the measurement sample was heated to a temperature above the melting point at a heating rate of 10 °C / min to melt it and then cooled at a cooling rate of 20 °C / min.

[0217] <Half-crystallization time>

[0218] The half-crystallization time of the polyimide resin was measured using a differential scanning calorimeter (DSC-6220 manufactured by SIINanoTechnologyInc.).

[0219] After maintaining the polyimide resin at 420 °C for 10 minutes in a nitrogen atmosphere to completely melt it, when performing a quenching operation at a cooling rate of 70 °C / minute, the time taken from the appearance of the observed crystallization peak to reaching the peak top was calculated. It should be noted that in Table 1, cases where the half-crystallization time is 20 seconds or less are denoted as "<20".

[0220] <Weight-average molecular weight>

[0221] The weight-average molecular weight (Mw) of the polyimide resin was measured using the gel permeation chromatography (GPC) measurement device "Shodex GPC-101" manufactured by Showa Denko K.K. under the following conditions.

[0222] Column: Shodex HFIP-806M

[0223] Mobile phase solvent: Hexafluoroisopropanol (HFIP) containing 2 mM sodium trifluoroacetate

[0224] Column temperature: 40 °C

[0225] Mobile phase flow rate: 1.0 mL / min

[0226] Sample concentration: Approximately 0.1 mass%

[0227] Detector: IR detector

[0228] Injection volume: 100 μm

[0229] Standard curve: Standard PMMA

[0230] <Heat distortion temperature (HDT)>

[0231] Using the resin used in each example alone or the resin composition obtained in each example, a molded body of 80 mm × 10 mm × thickness 4 mm was manufactured by the injection molding method described below for measurement.

[0232] The measurement was carried out in accordance with JIS K7191-1,2:2015, and a flatwise test was performed. Specifically, using an HDT test device "Auto-HDT3D-2" (manufactured by Toyo Seiki Seisaku-sho, Ltd.), the heat distortion temperature was measured under the conditions of a distance between supports of 64 mm, a load of 1.80 MPa, and a heating rate of 120 °C / hour.

[0233] <Film formability>

[0234] The resin used in each example alone or the pellets of the resin composition obtained in each example were put into a LABOPLASTMILL T-die extrusion forming device (manufactured by Toyo Seiki Seisaku-sho, Ltd., extruder Φ20 mm, L / D = 25, die width of the T-die 150 mm, die lip width 0.4 mm), and extrusion forming was carried out for about 15 minutes under the conditions of an extrusion temperature of 310 to 350 °C and a target thickness of 50 μm to produce a film. The film during extrusion forming was visually observed, and the film formability was evaluated according to the following criteria.

[0235] A: No protrusions or accumulations (eye varnish) were seen on the film surface.

[0236] B: Some protrusions and accumulations were seen on the film surface, but they were within the allowable range.

[0237] C: A large number of protrusions and accumulations were generated on the film surface.

[0238] <Dielectric constant, dielectric loss tangent>

[0239] Using the resin used in each example alone or the resin composition obtained in each example, a film with a thickness of 50 to 60 μm was manufactured by the method described in the "Film Formability" evaluation for measurement. Using a "PNA Network Analyzer N5222B" manufactured by Keysight Technologies and a cavity resonator "CP531" manufactured by Kanto Electronics Co., Ltd. Application Development, according to IEC 62810, the dielectric constant and dielectric loss tangent were measured by the cavity resonance perturbation method at a temperature of 23 °C, a humidity of 50%, and a measurement frequency of 10 GHz. The measured values were the average values for n = 2. After the film was conditioned at a temperature of 23 °C and a humidity of 50% for more than 24 hours, it was quickly used for measurement.

[0240] <Coefficient of thermal expansion (CTE)>

[0241] CTE was measured according to JIS K7197:2012. Using the resin used in each example alone or the pellets of the resin composition obtained in each example, an injection molded body of JIS K 7139:2009 multi-purpose test piece type A1 was produced by the method described below. A test piece with a size of 5 mm × 4 mm × 10 mm was cut out from the parallel part of the injection molded body for measurement.

[0242] Using the above test piece as a measurement sample, a thermomechanical analysis (TMA) measurement was performed using a thermomechanical analyzer "TMA7100C" manufactured by Hitachi High-Tech Science Corporation. In a nitrogen gas stream (150 mL / min), in compression mode, heating was carried out from 23 °C to 300 °C under the conditions of a load of 49 mN and a heating rate of 5 °C / min. TMA measurements were performed on the flow direction (MD) and the direction orthogonal thereto (TD) of the injection molded body, and the CTE was determined from the measured values at 23 °C to 210 °C. In addition, (CTE of MD + CTE of TD) / 2 was set as the average value of the CTEs of MD and TD.

[0243] Production Example 1 (Production of Polyimide Resin 1)

[0244] Into a 2 L separable flask equipped with a Dean-Stark apparatus, a Liebig condenser, a thermocouple, and 4 paddle blades, 500 g of 2-(2-methoxyethoxy)ethanol (manufactured by Nippon Emulsion Co., Ltd.) and 218.12 g (1.00 mol) of pyromellitic dianhydride (manufactured by Mitsubishi Gas Chemical Co., Inc.) were introduced. After purging with nitrogen, stirring was carried out at 150 rpm to form a uniform suspension solution. On the other hand, using a 500 mL beaker, 49.79 g (0.35 mol) of 1,3-bis(aminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Inc., cis / trans ratio = 7 / 3) and 93.77 g (0.65 mol) of 1,8-octamethylenediamine (manufactured by Kanto Chemical Co., Inc.) were dissolved in 250 g of 2-(2-methoxyethoxy)ethanol to prepare a mixed diamine solution. This mixed diamine solution was slowly added using a piston pump. Exotherm occurred due to the dropwise addition, but the internal temperature was adjusted to be 40 °C to 80 °C. The entire process of dropwise adding the mixed diamine solution was under a nitrogen purge state, and the stirring blade speed was 250 rpm. After the dropwise addition was completed, 130 g of 2-(2-methoxyethoxy)ethanol and 1.284 g (0.010 mol) of n-octylamine (manufactured by Kanto Chemical Co., Inc.) as a capping agent were added and further stirred. At this stage, a pale yellow polyamic acid solution was obtained. Then, after setting the stirring speed to 200 rpm, the polyamic acid solution in the 2 L separable flask was heated to 190 °C. During the heating process, precipitation of polyimide resin powder and dehydration accompanying imidization were confirmed between 120 and 140 °C of the liquid temperature. After holding at 190 °C for 30 minutes, it was cooled to room temperature and filtered. The obtained polyimide resin powder was washed with 300 g of 2-(2-methoxyethoxy)ethanol and 300 g of methanol, filtered, and then dried in a dryer at 180 °C for 10 hours to obtain 317 g of a crystalline thermoplastic polyimide resin 1 (hereinafter also simply referred to as "polyimide resin 1") powder.

[0245] The IR spectrum of polyimide resin 1 was measured, and characteristic absorptions of the imide ring were confirmed at ν(C=O) 1768 and 1697 (cm -1 ). The logarithmic viscosity was 1.30 dL / g, Tm was 323 °C, Tg was 184 °C, Tc was 266 °C, the heat of melting was 21.0 mJ / mg, the heat of crystallization was 20.3 mJ / mg, the half-crystallization time was 20 seconds or less, and Mw was 55,000.

[0246] Production Example 2 (Production of polyimide resin 2)

[0247] 769 g of 2-(2-methoxyethoxy)ethanol (manufactured by Nippon Emulsion Co., Ltd.) and 174.50 g (0.80 mol) of pyromellitic dianhydride (manufactured by Mitsubishi Gas Chemical Co., Ltd.) were introduced into a 2 L separable flask equipped with a Dean-Stark apparatus, a Liebig condenser, a thermocouple, and four-blade impellers. After purging with nitrogen, stirring was carried out at 150 rpm to form a homogeneous suspension. On the other hand, using a 500 mL beaker, 22.76 g (0.16 mol) of 1,3-bis(aminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd., cis / trans ratio = 7 / 3) and 92.33 g (0.64 mol) of 1,8-octamethylenediamine (manufactured by Kanto Chemical Co., Inc.) were dissolved in 250 g of 2-(2-methoxyethoxy)ethanol to prepare a mixed diamine solution. This mixed diamine solution was slowly added using a piston pump. Exotherm occurred during the dropwise addition, but the internal temperature was adjusted to be 40 °C to 80 °C. Nitrogen was flowing throughout the dropwise addition of the mixed diamine solution, and the stirring blade speed was 250 rpm. After the dropwise addition was completed, 10 g of 2-(2-methoxyethoxy)ethanol and 1.027 g (0.008 mol) of n-octylamine (manufactured by Kanto Chemical Co., Inc.) as a capping agent were added and further stirred. At this stage, a pale yellow polyamic acid solution was obtained. Then, after setting the stirring speed to 200 rpm, the polyamic acid solution in the 2 L separable flask was heated to 185 °C. During the heating process, precipitation of polyimide resin powder and dehydration accompanied by imidization were confirmed between 120 and 140 °C of the liquid temperature. After holding at 185 °C for 30 minutes, it was cooled to room temperature and filtered. The obtained polyimide resin powder was washed with 600 g of methanol, filtered, and then dried at 185 °C for 10 hours using a dryer to obtain 256 g of powder of crystalline thermoplastic polyimide resin 2 (hereinafter also simply referred to as "polyimide resin 2").

[0248] For polyimide resin 2, Tm was 344 °C, Tg was 166 °C, Tc was 299 °C, the heat of melting was 40 mJ / mg, the heat of crystallization was 35 mJ / mg, and Mw was 36,000.

[0249] The composition and evaluation results of the polyimide resins obtained in Production Examples 1 to 2 are shown in Table 1. It should be noted that the molar percentages of the tetracarboxylic acid component and the diamine component in Table 1 are values calculated from the input amounts of the respective components during the production of the polyimide resin.

[0250] [Table 1]

[0251] Table 1

[0252]

[0253] *1: Content ratio (mol%) of the repeating structural unit of formula (1) in the polyimide resin relative to the total of the repeating structural unit of formula (1) and the repeating structural unit of formula (2)

[0254] The abbreviations in Table 1 are as follows.

[0255] ·PMDA: Pyromellitic dianhydride

[0256] ·1,3-BAC: 1,3-Bis(aminomethyl)cyclohexane

[0257] ·OMDA: 1,8-Octamethylenediamine

[0258] ·n-OcA: n-Octylamine

[0259] Example 1 (Production and Evaluation of Resin Composition)

[0260] The powder of the polyimide resin 1 obtained in Production Example 1 and the powder of poly(2,6-dimethyl-1,4-phenylene ether) (manufactured by Polyxylenol Singapore Pte Ltd, "PX100F", Tg = 207°C, intrinsic viscosity at 30°C measured in chloroform = 0.37 dL / g) as component (B) were dry-blended at the ratios shown in Table 2, and then melt-kneaded and extruded using a co-rotating twin-screw kneading extruder (manufactured by PARKER CORPORATION, "HK-25D", screw diameter 25 mmΦ, L / D = 41) under the conditions of a barrel temperature of 330 to 340°C and a screw rotation speed of 120 rpm. The strand extruded from the extruder was air-cooled and then pelletized using a granulator (manufactured by Hoshi Plastics Co., Ltd., "Fan Cutter FC-Mini-4 / N"). The obtained pellets were dried at 80°C for 12 hours and then used for injection molding.

[0261] Using an injection molding machine (manufactured by FANUC CORPORATION, "Roboshotα-S30iA"), injection molding was carried out at a barrel temperature of 360°C, a mold temperature of 180°C, and a molding cycle of 67 seconds to produce an injection molded body of a specified shape for the above evaluation.

[0262] In addition, a thin film is produced by the method described in the above "thin film formability" evaluation.

[0263] Using the obtained pellets, injection molded articles, or thin films, various evaluations are performed by the above method. The results are shown in Table 2.

[0264] Examples 2 to 4, Comparative Examples 2 to 4

[0265] The powder of polyimide resin 1 obtained in Production Example 1 and the powder of poly(2,6-dimethyl-1,4-phenylene ether) "PX100F" are used in the proportions shown in Table 2, and injection molding is performed within the range of a molding cycle of 52 seconds to 77 seconds (Example 2: 52 seconds, Example 3: 65 seconds, Example 4: 67 seconds, Comparative Example 2: 67 seconds, Comparative Example 3: 72 seconds, Comparative Example 4: 77 seconds). Except for this, pellets, injection molded articles, and thin films are produced in the same manner as in Example 1, and various evaluations are performed. The results are shown in Table 2.

[0266] Comparative Example 1

[0267] The powder of polyimide resin 1 obtained in Production Example 1 is melt-kneaded and extruded using a LABO PLASTMILL (manufactured by Toyo Seiki Seisaku-sho, Ltd.) at a barrel temperature of 360°C and a screw rotation speed of 150 rpm. After the strand extruded from the extruder is air-cooled, it is pelletized using a granulator "Fan Cutter FC-Mini-4 / N" manufactured by Hoshi Plastics Co., Ltd. The obtained pellets are dried at 150°C for 12 hours and then used for injection molding.

[0268] Using an injection molding machine ("ROBOSHOTα-S30iA" manufactured by FANUC Corporation), injection molding is performed at a barrel temperature of 350°C, a mold temperature of 200°C, and a molding cycle of 50 seconds to produce an injection molded article of a specified shape for the above evaluation (HDT measurement).

[0269] In addition, a thin film is produced by the method described in the above "thin film formability" evaluation.

[0270] Using the obtained pellets, injection molded articles, or thin films, various evaluations are performed by the above method. The results are shown in Table 2.

[0271] [Table 2]

[0272] Table 2

[0273]

[0274] Example 5, Comparative Examples 5 to 7

[0275] In Example 1, “PX100L” manufactured by Polyxylenol Singapore Pte Ltd was used in the proportion shown in Table 3 to replace “PX100F” as poly(2,6-dimethyl-1,4-phenylene ether). Except for this, pellets, injection molded articles, and films were produced in the same manner as above, and various evaluations were carried out. The results are shown in Table 3.

[0276] Comparative Example 8

[0277] In Comparative Example 1, the polyimide resin 2 obtained in Production Example 2 was used instead of the polyimide resin 1, the barrel temperature during injection molding was changed to 360 °C, and the mold temperature was changed to 180 °C. Except for this, pellets, injection molded articles, and films were produced in the same manner as above, and various evaluations were carried out. The results are shown in Table 3.

[0278] Example 6

[0279] In Example 1, the polyimide resin 2 obtained in Production Example 2 and “PX100L” manufactured by Polyxylenol Singapore Pte Ltd as poly(2,6-dimethyl-1,4-phenylene ether) were used in the proportion shown in Table 3. Except for this, pellets, injection molded articles, and films were produced in the same manner as above, and various evaluations were carried out. The results are shown in Table 3.

[0280] Example 7

[0281] In Example 5, maleic anhydride-modified polyphenylene ether (Iupiace PME-80 manufactured by Mitsubishi Engineering-Plastics Corporation, maleic anhydride modification rate: 0.38% by mass) was used instead of “PX100L”, the barrel temperature during injection molding was changed to 360 °C, and the mold temperature was changed to 160 °C. Except for this, pellets, injection molded articles, and films were produced in the same manner as above, and various evaluations were carried out. The results are shown in Table 3.

[0282] [Table 3]

[0283] Table 3

[0284]

[0285] The details of each component shown in Tables 2 to 3 are as follows.

[0286] <Component (A)>

[0287] · Polyimide resin 1: Crystalline thermoplastic polyimide resin 1 obtained in Production Example 1

[0288] · Polyimide resin 2: Crystalline thermoplastic polyimide resin 2 obtained in Production Example 2

[0289] <Component (B)>

[0290] · PX100F: Poly(2,6-dimethyl-1,4-phenylene ether), "PX100F" manufactured by Polyxylenol Singapore Pte Ltd, Tg = 207 °C, intrinsic viscosity at 30 °C measured in chloroform = 0.37 dL / g

[0291] · PX100L: Poly(2,6-dimethyl-1,4-phenylene ether), "PX100L" manufactured by Polyxylenol Singapore Pte Ltd, Tg = 210 °C, intrinsic viscosity at 30 °C measured in chloroform = 0.47 dL / g

[0292] · PME80: Maleic anhydride modified polyphenylene ether, "Iupiace PME-80" manufactured by Mitsubishi Engineering-Plastics Corporation, maleic anhydride modification rate 0.38 mass%

[0293] As shown in Tables 2 to 3, the film formability of the resin compositions of this example is good. Furthermore, the molded articles formed from the resin compositions of Examples 1 to 5 and 7 exhibit lower dielectric properties and lower CTE than the molded article of Comparative Example 1 formed from Component (A), and particularly exhibit a low CTE in the MD direction. The molded article formed from the resin composition of Example 6 also exhibits lower dielectric properties than the molded article of Comparative Example 8 formed from Component (A).

[0294] It is also known that the heat of fusion Hm of the resin compositions of Examples 1 to 5 and 7 is higher than that of Comparative Examples 2 to 7, that is, they have high crystallinity.

[0295] Furthermore, the morphology of the pellets obtained in Example 5 was confirmed by the following method.

[0296] Using an ultramicrotome ("EM UC7" manufactured by Leica Microsystems), as Figure 1 shown, the pellets obtained in Example 5 were cut in a direction orthogonal to the flow direction (MD) of the pellets (i.e., in a manner to form a TD cross-section) to produce ultrathin sections. In Figure 1 , 1 is the pellet and 2 is the ultrathin section.

[0297] After staining the section in the gas phase of ruthenium tetroxide for 30 minutes, a field emission scanning transmission electron microscope (FE-STEM, "Gemini SEM500" manufactured by Carl Zeiss) was used at an acceleration voltage: 30 kV, column mode: Normal, aperture size: 20 μm, working distance: 3.6 mm, detection signal: aSTEM A, observation magnification: 10,000 times, and transmission observation was performed using a STEM detector ( Figure 2 ). InFigure 2 In the observed image, the dark part corresponds to the stained portion, and the bright part corresponds to the non-stained portion. In the observed image, the portion judged to have a deep color is composed of the resin (B) that is easily stained with ruthenium tetroxide.

[0298] From Figure 2 it can be seen that in the pellets obtained in Example 5, the polyimide resin (A) and the resin (B) form a sea-island structure. In addition, it is speculated that the polyimide resin (A) forms the sea portion and the resin (B) forms the island portion.

[0299] Examples 8 to 11

[0300] The powder of the polyimide resin 1 obtained in Production Example 1 and the powder of poly(2,6-dimethyl-1,4-phenylene ether) "PX100F" were used in the proportions shown in Table 4, and further, the amounts of additives shown in Table 4 were compounded, and injection molding was carried out with a molding cycle of 61 seconds to 88 seconds. Except for this, pellets, injection molded articles, and films were produced in the same manner as in Example 1, and various evaluations were performed. The results are shown in Table 4.

[0301] In addition, the oxygen index described in Table 4 was evaluated by the following method.

[0302] <Oxygen Index>

[0303] Using the resins used in each example alone and the resin compositions produced in each example, injection molded articles of 80 mm × 10 mm × thickness 4 mm were produced by the above method. This molded article was used as a test piece, and the oxygen index was measured using a candle-type combustion tester D type (manufactured by Toyo Seiki Seisaku-sho, Ltd.) by the method according to JIS K 7201:1995. The higher the oxygen index, the more excellent the flame retardancy.

[0304] [Table 4]

[0305] Table 4

[0306]

[0307] The details of each component shown in Table 4 are as follows.

[0308] <Component (A)>

[0309] · Polyimide resin 1: Crystalline thermoplastic polyimide resin 1 obtained in Production Example 1

[0310] <Component (B)>

[0311] · PX100F: Poly(2,6-dimethyl-1,4-phenylene ether), "PX100F" manufactured by Polyxylenol Singapore Pte Ltd, Tg = 207 °C, intrinsic viscosity at 30 °C measured in chloroform = 0.37 dL / g

[0312] <Additive>

[0313] · 201FF: "201FF Stabilizer" manufactured by PolyAd Services GmbH, antioxidant, KI / CuI / ZnStearate = 80 / 10 / 10 (mass ratio)

[0314] · Irganox 1010: Pentaerythritol tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], manufactured by BASF Japan Ltd., phenolic antioxidant

[0315] · SR-3000: manufactured by Daihachi Chemical Industry Co., Ltd., condensed phosphate-based flame retardant

[0316] As shown in Table 4, in resin compositions containing additives such as antioxidants and flame retardants, low dielectric properties and film formability can also be maintained. In particular, the resin compositions of Examples 10 and 11 containing flame retardants exhibit excellent low dielectric properties and flame retardancy.

[0317] Industrial Applicability

[0318] According to the present invention, it is possible to provide a resin composition having excellent low dielectric properties and good film formability, and a molded article containing the resin composition.

Claims

1. A resin composition, comprising: a polyimide resin (A) containing a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), and the content ratio of the repeating structural unit of formula (1) relative to the total of the repeating structural unit of formula (1) and the repeating structural unit of formula (2) is 20 to 70 mol%; and a resin represented by the following formula (5) or its acid-modified product (B), the content mass ratio of the component (B) relative to the total content mass of the component (A) and the component (B) [(B) / {(A)+(B)}] is 0.50 or less, R1 is a divalent group having 6 to 22 carbon atoms containing at least 1 alicyclic hydrocarbon structure; R2 is a divalent linear aliphatic group having 5 to 16 carbon atoms; X1 and X2 are each independently a tetravalent group having 6 to 22 carbon atoms containing at least 1 aromatic ring; R 51 ~R 55 and R 61 ~R 64 Each independently represents a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 4 carbon atoms, and R 65 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; n is the number of repeating structural units and is a number of 10 or more.

2. The resin composition according to claim 1, wherein, the total content of the component (A) and the component (B) in the resin composition is 50% by mass or more.

3. The resin composition according to claim 1 or 2, wherein, The intrinsic viscosity of the component (B) measured in chloroform at 30 °C is 0.20 to 0.60 dL / g.

4. The resin composition according to any one of claims 1 to 3, wherein The resin composition is obtained by melt-kneading at a temperature higher than the melting point of the component (A).

5. The resin composition according to any one of claims 1 to 4, wherein, The pellets formed from the resin composition have a microphase-separated structure.

6. The resin composition according to any one of claims 1 to 5, having a dielectric constant of 3.0 or less and a dielectric loss tangent of 0.005 or less at a measurement frequency of 10 GHz.

7. The resin composition according to any one of claims 1 to 6, wherein The absolute value of the coefficient of linear thermal expansion in the temperature range of 23 to 210 °C measured according to JIS K7197:2012 of the molded article formed from the resin composition is 100 ppm / °C or less.

8. A molded article comprising the resin composition according to any one of claims 1 to 7.

9. The shaped body according to claim 8, wherein, The molded article is a film.

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