Antenna substrate material and manufacturing method therefor

Abstract

The present disclosure relates to an antenna substrate material containing a block copolymer, wherein the block copolymer includes a polyimide block (BI) and a polyamide acid block (BA).

Description

Antenna substrate material and its manufacturing method

[0001] The present disclosure relates to an antenna substrate material, a method for producing an antenna substrate material, and an antenna substrate material composition.

[0002] 5G (5th Generation Mobile Communication System), which allows simultaneous connection of large volumes of data without delay, is expanding. Looking ahead to post-5G, an increase in the number of wireless slave stations and their high functionality are required to further increase the operating frequency. Radio units (RUs) included in wireless slave stations employ antennas such as patch antennas for transmitting and receiving radio waves. The patch antenna, for example, has a multilayer substrate including an insulating substrate and an antenna element mounted on the multilayer substrate (see Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2020-174114

[0004] In order to obtain good transmission characteristics, it is desirable that the organic material contained in the multilayer substrate has low dielectric constant and low thermal expansion coefficient. The present disclosure provides an antenna substrate material, an antenna substrate material composition, and a method for producing the antenna substrate material, which exhibit a low dielectric constant, a low dielectric loss tangent, and a low thermal expansion coefficient.

[0005] The present invention includes the following embodiments, but is not limited to the following embodiments.

[0006] One embodiment relates to a substrate material for an antenna containing a block copolymer, the block copolymer including a polyimide block (BI) and a polyamic acid block (BA).

[0007] Another embodiment contains a block copolymer, the block copolymer containing a polyimide block (BI) and a polyamic acid block (BA), and containing a structural unit represented by the following formula (I) and a structural unit represented by the following formula (A), and the block copolymer contains at least the following R Ａ and the following R Ｃ are different, or at least the following R Ｂ and the following R Ｄ The present invention relates to a substrate material for an antenna, which is different from the above. (In the formula, R Ａ and R Ｂ each independently represents an organic group. (In the formula, R Ｃ and R Ｄ each independently represents an organic group.

[0008] Another embodiment relates to an antenna substrate material containing a block copolymer, wherein the block copolymer includes a polyimide block (BI) and a polyamic acid block (BA), and has a structure derived from a diamine or a diisocyanate and a structure derived from a tetracarboxylic dianhydride.

[0009] Another embodiment relates to a method for producing an antenna substrate material containing a block copolymer, the method including obtaining a polyimide (PI) using a diamine or a diisocyanate and a tetracarboxylic dianhydride, obtaining a polyamic acid (PA) using a diamine and the tetracarboxylic dianhydride, and obtaining a block copolymer using the polyimide (PI) and the polyamic acid (PA).

[0010] Another embodiment relates to an antenna substrate material composition containing any of the antenna substrate materials described above and a solvent.

[0011] According to the present disclosure, it is possible to provide an antenna substrate material, an antenna substrate material composition, and a method for producing an antenna substrate material that exhibit a low dielectric constant, a low dielectric loss tangent, and a low thermal expansion coefficient.

[0012] Fig. 1 is a schematic diagram showing an example of an antenna substrate, and Fig. 2 is a schematic diagram showing an example of an antenna substrate.

[0013] The following describes embodiments of the present invention. The present invention is not limited to the following embodiments. The following embodiments can be implemented alone or in combination. Combinations of multiple embodiments are also included in the present invention.

[0014] In the numerical ranges described in stages in the present disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range. Furthermore, the upper or lower limit value of a numerical range described in the present disclosure may be replaced with a value shown in the Examples. A numerical value may be selected from the upper and lower limit values ​​described in stages in the present disclosure to form a stepped numerical range. Furthermore, the upper and lower limit values ​​described in the present disclosure may be replaced with values ​​shown in the Examples. In the present disclosure, each component may contain multiple corresponding substances. When multiple substances corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, each structure in the polymer may contain multiple corresponding structures. When multiple structures corresponding to each structure are present in the polymer, the content or amount of each structure means the total content or amount of the multiple structures present in the polymer, unless otherwise specified. In the present disclosure, the term "layer" includes not only a layer that is formed over the entire area when the area where the layer exists is observed, but also a layer that is formed only over a portion of the area. The same applies to "film."

[0015] <Antenna Substrate Material> In some embodiments, the antenna substrate material contains a block copolymer including a polyimide block (BI) and a polyamic acid block (BA). The antenna substrate material may further contain optional components. The antenna substrate material is a material used to form a substrate for an antenna. The antenna substrate is, for example, a substrate for mounting an antenna element such as a patch antenna, or a substrate for mounting an antenna device including an antenna element.

[0016] <Block Copolymer> The block copolymer contains a polyimide block (BI) and a polyamic acid block (BA). The block copolymer containing the polyimide block (BI) and the polyamic acid block (BA) contains an imide bond (also referred to as an "imide group") and an amic acid bond (also referred to as an "amic acid structure" or an "amic acid group") in the polymer chain. The polyamic acid block (BA) may be a block that becomes a polyimide block (BI-A) different from the polyimide block (BI) upon ring closure of the amic acid bond. The block copolymer may further contain an optional block different from the polyimide block (BI) and the polyamic acid block (BA). The block copolymer may contain one or more optional blocks.

[0017] In the present disclosure, whether blocks are the same or different can be distinguished by the structural units contained in the blocks. For example, if one block contains a structural unit that is not contained in the other block, the two blocks are different blocks. Examples of combinations of two different types of blocks include when block 1 contains structural unit 1 and block 2 contains structural unit 2; when block 1 contains structural unit 1 and block 2 contains structural unit 1 and structural unit 2; when block 1 contains structural unit 1 and structural unit 2 and block 2 contains structural unit 1 and structural unit 3; etc. The structural units 1, 2, and 3 used in the description here are different structural units. In the present disclosure, the number of types of structural units contained in each block is not limited to one or two, and may be three or more. In the present disclosure, the number of types of blocks contained in a block copolymer is not limited to two, and may be three or more.

[0018] In general, polyimides tend to exhibit lower dielectric constants and lower dielectric dissipation factors as the intramolecular free volume increases. The free volume can be increased by introducing bulky groups into the polyimide, providing substituents at appropriate positions to introduce a twisted structure into the skeleton, or providing linking groups such as ether bonds (oxy groups), carbonyl bonds (carbonyl groups), and sulfonyl bonds (sulfonyl groups) to the skeleton to introduce a bent structure into the skeleton. On the other hand, polyimides tend to exhibit lower thermal expansion coefficients as the molecule becomes more rigid. Polyimides that lack these groups and have benzene ring structures, biphenyl structures, etc., become more rigid molecules. Therefore, it is usually difficult to achieve both a low dielectric constant and low dielectric dissipation factor and a low thermal expansion coefficient. In contrast, the present disclosure provides a material containing a block copolymer that enables these two properties to be achieved. Note that the discussions, speculations, and other statements in this disclosure do not limit the present invention.

[0019] In some embodiments, the block copolymer includes a block with a large free volume and a rigid block. For example, the polyimide block (BI) and the polyamic acid block (BA) may be a combination of a block containing a structural unit that increases the free volume of the polyimide and a block containing a structural unit that increases the rigid structure of the polyimide. For example, the polyimide block (BI) and the polyamic acid block (BA) may be a combination of a block containing a structural unit containing a non-aromatic hydrocarbon group, a structural unit containing a linking group such as an oxy group or a carbonyl group in the skeleton, and a block that does not contain a structural unit containing a non-aromatic hydrocarbon group, a structural unit containing a linking group such as an oxy group or a carbonyl group in the skeleton, or a block that contains less of these structural units than the above blocks. For example, the polyimide block (BI) and the polyamic acid block (BA) may be a combination of a block exhibiting a dielectric constant A, a dielectric loss tangent B, and a coefficient of thermal expansion C, and a block exhibiting a dielectric constant a smaller than A, a dielectric loss tangent b smaller than B, and a coefficient of thermal expansion c larger than C. In the present disclosure, polyimides obtained from materials containing block copolymers have a low dielectric constant, a low dielectric loss tangent, and a low coefficient of thermal expansion.

[0020] [Block Copolymer Comprising Structural Unit (X)] In some embodiments, the block copolymer comprises a polyimide block (BI) and a polyamic acid block (BA), and comprises a structural unit (X) having a group (X) comprising at least one non-aromatic hydrocarbon group. In the present disclosure, the "group (X) comprising at least one non-aromatic hydrocarbon group" may be simply referred to as the "group (X)" or the "hydrocarbon group (X)." In the present disclosure, the "structural unit (X) having a group (X) comprising at least one non-aromatic hydrocarbon group" may be simply referred to as the "structural unit (X)." The hydrocarbon group (X) may be a pair of imide groups, an amic acid group, or a group located between an imide group and an amic acid group. The block copolymer may comprise one or more hydrocarbon groups (X). When the block copolymer comprises the hydrocarbon group (X), the polyimide tends to have a low dielectric constant and a low dielectric loss tangent.

[0021] The block copolymer may contain a structural unit other than the structural unit (X). Examples of structural units other than the structural unit (X) include the structural unit (Y) described below. The structural unit (Y) may be a structural unit having a group (Y) containing at least one aromatic ring group. In the present disclosure, the "group (Y) containing at least one aromatic ring group" may be simply referred to as the "group (Y)" or the "organic group (Y)." In the present disclosure, the "structural unit (Y) having a group (Y) containing at least one aromatic ring group" may be simply referred to as the "structural unit (Y)."

[0022] When the block copolymer contains the structural unit (X), only one of the polyimide block (BI) and the polyamic acid block (BA) may contain the structural unit (X), or both the polyimide block (BI) and the polyamic acid block (BA) may contain the structural unit (X). The polyimide block (BI) and the polyamic acid block (BA) may each independently contain one or more types of structural unit (X). For example, the block copolymer may be a block copolymer containing a polyimide block (BI) containing the structural unit (X) and a polyamic acid block (BA) containing a structural unit (X) different from the structural unit (X).

[0023] When the block copolymer contains the structural unit (Y), only one of the polyimide block (BI) and the polyamic acid block (BA) may contain the structural unit (Y), or both the polyimide block (BI) and the polyamic acid block (BA) may contain the structural unit (Y). The polyimide block (BI) and the polyamic acid block (BA) may each independently contain one or more types of structural unit (Y). For example, the block copolymer may be a block copolymer containing a polyimide block (BI) containing the structural unit (X) and a polyamic acid block (BA) containing the structural unit (Y), or a block copolymer containing a polyimide block (BI) containing the structural unit (Y) and a polyamic acid block (BA) containing the structural unit (X).

[0024] (Structural Unit (X)) The structural unit (X) at least contains a hydrocarbon group (X). The structural unit (X) may further contain at least one of an imide group and an amic acid group. The total number of carbon atoms in the "at least one non-aromatic hydrocarbon group" contained in the hydrocarbon group (X) is 1 or more. The number of carbon atoms contained in the imide group and the amic acid group is not included in the total number of carbon atoms in the at least one non-aromatic hydrocarbon group in the hydrocarbon group (X). For example, the structural unit (X) is a structural unit containing a hydrocarbon group (X) and an imide group or an amic acid group. The block copolymer may contain the hydrocarbon group (X) contained in the structural unit (X) and the imide group or the amic acid group in the polymer chain. The structural unit (X) may contain one or more types of hydrocarbon groups (X). The structural unit (X) may further contain an optional group other than the hydrocarbon group (X), the imide group, and the amic acid group. Examples of the optional group include organic groups such as an organic group (Y). In the present disclosure, an "organic group" is a group containing at least one carbon atom. The organic group (Y) may be a group between an imide group and an imide group, an amic acid group and an amic acid group, or a group located between an imide group and an amic acid group. The block copolymer may contain the organic group (Y) in the polymer chain.

[0025] (Hydrocarbon Group (X)) The hydrocarbon group (X) contains at least one non-aromatic hydrocarbon group. In the hydrocarbon group (X), the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 1 or more. When the hydrocarbon group (X) contains one non-aromatic hydrocarbon group, the total number of carbon atoms means the total number of carbon atoms contained in the one non-aromatic hydrocarbon group. When the hydrocarbon group (X) contains two or more non-aromatic hydrocarbon groups, the total number of carbon atoms means the total number of carbon atoms contained in the two or more non-aromatic hydrocarbon groups. When the hydrocarbon group (X) contains two or more non-aromatic hydrocarbon groups, the two or more non-aromatic hydrocarbon groups may be the same or different. The hydrocarbon group (X) may further contain any group other than a non-aromatic hydrocarbon group. The hydrocarbon group (X) is, for example, a monovalent to tetravalent group. The structural unit (X) preferably contains a divalent to tetravalent hydrocarbon group (X), more preferably contains a divalent or tetravalent hydrocarbon group (X), and even more preferably contains a divalent hydrocarbon group (X).

[0026] The non-aromatic hydrocarbon group is a non-aromatic hydrocarbon group that does not contain an aromatic ring. At least one non-aromatic hydrocarbon group is, for example, a saturated aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, an unsaturated alicyclic hydrocarbon group, or a group consisting of two or more selected from these. The saturated aliphatic hydrocarbon group may be linear or branched. The unsaturated aliphatic hydrocarbon group may be linear or branched.

[0027] Below are examples of hydrocarbon groups (X) and the total number of carbon atoms in at least one non-aromatic hydrocarbon group contained in the hydrocarbon group (X). Furthermore, as a reference example, below are examples of organic groups (Y) and the total number of carbon atoms in at least one non-aromatic hydrocarbon group contained in the organic group (Y). The number of carbon atoms contained in the —C(O)— group is not included in the total number of carbon atoms. The number of carbon atoms contained in a non-aromatic hydrocarbon group in which a hydrogen atom has been substituted with a halogen atom is included in the total number of carbon atoms. In the present disclosure, "*" in a formula indicates the bonding position to another atom. Groups 7 to 14 are examples of hydrocarbon groups (X), and groups 1 to 3 are examples of organic groups (Y). Groups 4 to 6 are examples of hydrocarbon groups (X) and also examples of organic groups (Y).

[0028]

[0029] The total number of carbon atoms in the at least one non-aromatic hydrocarbon group contained in the hydrocarbon group (X) may be 1 to 50. The carbon number is, for example, 2 or more, 3 or more, 6 or more, 9 or more, 12 or more, 16 or more, 20 or more, 24 or more, 28 or more, 32 or more, or 36 or more. The carbon number is, for example, 48 or less, 44 or less, 40 or less, or 36 or less. The carbon number is, for example, 6 to 50, 9 to 50, 12 to 48, 20 to 44, or 28 to 40. When the block copolymer contains a non-aromatic hydrocarbon group, it is believed that a polyimide having a low dielectric constant and a low dielectric loss tangent can be obtained due to reasons such as an increase in free volume and a decrease in polarity. When the total number of carbon atoms in the non-aromatic hydrocarbon group is 9 or more, these effects tend to be more easily achieved. When the total number of carbon atoms in the non-aromatic hydrocarbon group is 50 or less, good solubility in solvents can be maintained.

[0030] Examples of saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, unsaturated alicyclic hydrocarbon groups, and groups consisting of two or more selected from these that the hydrocarbon group (X) may contain are given below. The following examples can be applied to saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, unsaturated alicyclic hydrocarbon groups, and groups consisting of two or more selected from these in the present disclosure.

[0031] The number of carbon atoms in the saturated aliphatic hydrocarbon group is, for example, 1 to 50, 2 to 40, 3 to 30, 4 to 20, or 5 to 10. The saturated aliphatic hydrocarbon group is, for example, an atomic group formed by removing 1 to 4 hydrogen atoms from a linear or branched alkane. Examples of the alkane include methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, eicosane, heneicosane, docosane, tricosane, tetracosane, hexacosane, octacosane, triacontane, tetracontane, and pentacontane. When the hydrocarbon group (X) contains a saturated aliphatic hydrocarbon group having a small number of carbon atoms, such as 1, 2 or 3, the number of saturated aliphatic hydrocarbon groups in the hydrocarbon group (X) may be 2 or more.

[0032] The number of carbon atoms in the unsaturated aliphatic hydrocarbon group is, for example, 2 to 50, 2 to 40, 3 to 30, 4 to 20, or 5 to 10. The unsaturated aliphatic hydrocarbon group may contain one or more carbon-carbon unsaturated bonds, and may have, for example, 5 or less, 4 or less, 3 or less, or 2 or less. The unsaturated aliphatic hydrocarbon may be an alkene containing one carbon-carbon double bond or an alkyne containing one carbon-carbon triple bond. The unsaturated aliphatic hydrocarbon group is, for example, an atomic group obtained by removing 1 to 4 hydrogen atoms from a linear or branched alkene, or an atomic group obtained by removing 1 to 4 hydrogen atoms from a linear or branched alkyne. Examples of alkenes include ethene, propene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene, heneicosene, docosene, tricosene, tetracosene, pentacosene, hexacosene, heptacosene, octacosene, nonacosene, triacontene, tetracontene, and pentacontene. Examples of alkynes include ethyne, propyne, butyne, pentyne, hexyne, heptyne, octyne, nonyne, decyne, undecyne, dodecyne, tridecyne, tetradecyne, pentadecyne, hexadecyne, heptadecyne, octadecyne, nonadecyne, eicosine, heneicosine, docosine, tricosine, tetracosine, pentacosine, hexacosine, heptacosine, octacosine, nonacosine, triacontine, tetracontine, and pentacontine. When the hydrocarbon group (X) contains an unsaturated aliphatic hydrocarbon group having a small number of carbon atoms, for example, 1, 2, or 3 carbon atoms, the number of unsaturated aliphatic hydrocarbon groups in the hydrocarbon group (X) may be 2 or more.

[0033] The saturated alicyclic hydrocarbon group has, for example, 3 to 20, 4 to 16, 5 to 10, or 6 to 8 carbon atoms. The saturated alicyclic hydrocarbon group is, for example, an atomic group obtained by removing 1 to 4 hydrogen atoms from a cycloalkane. Examples of cycloalkanes include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, norbornane, decalin, bicyclobutane, bicyclohexane, bicyclooctane, spiropentane, spiroheptane, guadricyclane, and adamantane.

[0034] The number of carbon atoms in the unsaturated alicyclic hydrocarbon group is, for example, 4 to 20, 5 to 10, or 6 to 8. The unsaturated aliphatic hydrocarbon group may contain one or more carbon-carbon unsaturated bonds, and may have, for example, 5 or less, 4 or less, 3 or less, or 2 or less. The unsaturated aliphatic hydrocarbon may be a cycloalkene containing one carbon-carbon double bond or a cycloalkyne containing one carbon-carbon triple bond. The unsaturated alicyclic hydrocarbon group is, for example, an atomic group obtained by removing 1 to 4 hydrogen atoms from a cycloalkene, or an atomic group obtained by removing 1 to 4 hydrogen atoms from a cycloalkyne. Examples of unsaturated alicyclic hydrocarbons include cyclobutene, cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene, cycloheptene, norbornene, norbornadiene, and bicyclooctadiene.

[0035] The number of carbon atoms in the "group consisting of two or more selected from these" is, for example, 4 to 50, 9 to 50, 16 to 48, 24 to 44, or 32 to 40. The "group consisting of two or more selected from these" is a group consisting of two or more groups selected from the group consisting of saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, and unsaturated alicyclic hydrocarbon groups, wherein the two or more groups are bonded to each other. The "group consisting of two or more selected from these" includes, for example, at least one selected from the group consisting of a group consisting of a saturated aliphatic hydrocarbon group and a saturated alicyclic hydrocarbon group, a group consisting of a saturated aliphatic hydrocarbon group and an unsaturated alicyclic hydrocarbon group, a group consisting of an unsaturated aliphatic hydrocarbon group and a saturated alicyclic hydrocarbon group, and a group consisting of an unsaturated aliphatic hydrocarbon group and an unsaturated alicyclic hydrocarbon group.

[0036] Examples of optional groups that the hydrocarbon group (X) may contain include aromatic hydrocarbon groups, aromatic heterocyclic compound groups, and groups containing heteroatoms. Examples of aromatic hydrocarbon groups, aromatic heterocyclic compound groups, and groups containing heteroatoms that the hydrocarbon group (X) may contain are listed below. The following examples may be applied to the aromatic hydrocarbon groups, aromatic heterocyclic compound groups, and groups containing heteroatoms in the present disclosure. From the viewpoint of reducing polarity, the hydrocarbon group (X) may not contain an oxygen atom, and may also not contain a heteroatom.

[0037] The number of carbon atoms in the aromatic hydrocarbon group is, for example, 6 to 30, 6 to 20, or 6 to 10. The aromatic hydrocarbon group is, for example, an atomic group obtained by removing 1 to 4 hydrogen atoms from an aromatic hydrocarbon. Examples of aromatic hydrocarbons include benzene, naphthalene, anthracene, pyrene, and perylene. The number of carbon atoms in the aromatic heterocyclic compound group is, for example, 2 to 30, 4 to 20, or 5 to 10. The aromatic heterocyclic compound group is, for example, an atomic group obtained by removing 1 to 4 hydrogen atoms from an aromatic heterocyclic compound. Examples of aromatic heterocyclic compounds include pyridine, furan, benzofuran, thiophene, and benzothiophene.

[0038] Examples of groups containing a heteroatom include linking groups containing a heteroatom (excluding imide groups and amic acid groups) and substituents containing a heteroatom. Examples of linking groups containing a heteroatom include an oxy group, a thio group, a sulfonyl group, a sulfinyl group, a carbonyl group, a carbonyloxy group, and an imino group. Examples of substituents containing a heteroatom include a hydroxy group, a mercapto group, a sulfo group, a sulfino group, a carboxy group, a fluoro group, and a chloro group. In the present disclosure, the number of carbon atoms in the —C(O)— group contained in the group containing a heteroatom is not included in the total number of carbon atoms in the at least one non-aromatic hydrocarbon group.

[0039] The hydrocarbon group (X) is, for example, a non-aromatic hydrocarbon group having one or more carbon atoms. When the hydrocarbon group (X) is a non-aromatic hydrocarbon group having one or more carbon atoms, the hydrocarbon group (X) does not contain an aromatic hydrocarbon group, an aromatic heterocyclic compound group, or a group containing a heteroatom. The hydrocarbon group (X) is, for example, a saturated aliphatic hydrocarbon group; an unsaturated aliphatic hydrocarbon group; a saturated alicyclic hydrocarbon group; an unsaturated alicyclic hydrocarbon group; or a group consisting of two or more groups selected from saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, and unsaturated alicyclic hydrocarbon groups. The saturated aliphatic hydrocarbon group may be linear or branched. The unsaturated aliphatic hydrocarbon group may be linear or branched. When the hydrocarbon group (X) is a non-aromatic hydrocarbon group, the concentration of polar groups contained in the block copolymer is easily reduced.

[0040] The hydrocarbon group (X) is, for example, a non-aromatic hydrocarbon group having 9 or more carbon atoms. When the hydrocarbon group (X) is a non-aromatic hydrocarbon group, the hydrocarbon group (X) does not contain an aromatic hydrocarbon group, an aromatic heterocyclic compound group, or a group containing a heteroatom. The hydrocarbon group (X) is, for example, a saturated aliphatic hydrocarbon group having 9 or more carbon atoms; an unsaturated aliphatic hydrocarbon group having 9 or more carbon atoms; a saturated alicyclic hydrocarbon group having 9 or more carbon atoms; an unsaturated alicyclic hydrocarbon group having 9 or more carbon atoms; or a group having 9 or more carbon atoms and consisting of two or more selected from saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, and unsaturated alicyclic hydrocarbon groups. The saturated aliphatic hydrocarbon group may be linear or branched. The unsaturated aliphatic hydrocarbon group may be linear or branched. When the hydrocarbon group (X) is a non-aromatic hydrocarbon group having 9 or more carbon atoms, the concentration of polar groups contained in the block copolymer is easily reduced.

[0041] The hydrocarbon group (X) preferably contains at least one group selected from the group consisting of saturated alicyclic hydrocarbon groups and unsaturated alicyclic hydrocarbon groups, and more preferably contains a saturated alicyclic hydrocarbon group. The saturated alicyclic hydrocarbon group and the unsaturated alicyclic hydrocarbon group may have 3 or more, 5 or more, or 6 or more carbon atoms. The saturated alicyclic hydrocarbon group and the unsaturated alicyclic hydrocarbon group may have 20 or less, 10 or less, or 8 or less carbon atoms. When the block copolymer contains at least one of a saturated alicyclic hydrocarbon group and an unsaturated alicyclic hydrocarbon group, a polyimide with a lower dielectric constant tends to be obtained. This is presumably because the polyimide has an alicyclic structure, which increases the free volume.

[0042] The hydrocarbon group (X) preferably contains at least one group selected from the group consisting of linear saturated aliphatic hydrocarbon groups having 6 or more carbon atoms and linear unsaturated aliphatic hydrocarbon groups having 6 or more carbon atoms, and more preferably contains a linear saturated aliphatic hydrocarbon group having 6 or more carbon atoms. The linear saturated aliphatic hydrocarbon group and the linear unsaturated aliphatic hydrocarbon group may have 8 or more carbon atoms, 10 or more carbon atoms, or 12 or more carbon atoms. The linear saturated aliphatic hydrocarbon group and the linear unsaturated aliphatic hydrocarbon group may have 30 or less carbon atoms, 20 or less carbon atoms, or 16 or less carbon atoms. When the block copolymer contains at least one of a linear saturated aliphatic hydrocarbon group having 6 or more carbon atoms and a linear unsaturated aliphatic hydrocarbon group having 6 or more carbon atoms, a polyimide with a lower dielectric loss tangent tends to be obtained. This is presumably because the polyimide has a long chain structure, which reduces the concentration of imide groups in the polyimide, i.e., relatively reduces the number of polar groups in the polyimide.

[0043] The hydrocarbon group (X) preferably contains at least one group selected from the group consisting of saturated alicyclic hydrocarbon groups and unsaturated alicyclic hydrocarbon groups, and at least one group selected from the group consisting of linear saturated aliphatic hydrocarbon groups having 6 or more carbon atoms and linear unsaturated aliphatic hydrocarbon groups having 6 or more carbon atoms, and more preferably contains a saturated alicyclic hydrocarbon group and a linear saturated aliphatic hydrocarbon group having 6 or more carbon atoms.

[0044] In some embodiments, from the viewpoint of the balance between the dielectric constant and the dielectric loss tangent of the polyimide, the total number of carbon atoms of the saturated aliphatic hydrocarbon group and the unsaturated aliphatic hydrocarbon group contained in the hydrocarbon group (X) is greater than the total number of carbon atoms of the saturated alicyclic hydrocarbon group and the unsaturated alicyclic hydrocarbon group contained in the hydrocarbon group (X). In some embodiments, from the viewpoint of obtaining a low dielectric constant and a low dielectric loss tangent, the hydrocarbon group (X) does not contain an aromatic hydrocarbon group or an aromatic heterocyclic compound group.

[0045] The hydrocarbon group (X) preferably contains a group represented by the following formula (G1).

[0046]

[0047] In the formula, R ｘ represents a group (X) containing at least one non-aromatic hydrocarbon group.

[0048] The hydrocarbon group (X) more preferably contains at least one selected from the group consisting of groups represented by the following formulae (G2) to (G6), and groups represented by the following formulae (GA1) to (GA3b). The hydrocarbon group (X) further preferably contains at least one selected from the group consisting of groups represented by the following formulae (G2) to (G6). The hydrocarbon group (X) may contain at least one selected from the group consisting of groups represented by the following formulae (GA1) to (GA3b), instead of or in addition to the at least one selected from the group consisting of groups represented by the following formulae (G2) to (G6).

[0049]

[0050] In the formula, R ａ R each independently represents a linear or branched saturated aliphatic hydrocarbon group (having, for example, 1 or more, 6 or more, or 8 or more carbon atoms) or a linear or branched unsaturated aliphatic hydrocarbon group (having, for example, 1 or more, 6 or more, or 8 or more carbon atoms), and preferably represents a linear saturated aliphatic hydrocarbon group (having, for example, 1 or more, 6 or more, or 8 or more carbon atoms) or a linear unsaturated aliphatic hydrocarbon group (having, for example, 1 or more, 6 or more, or 8 or more carbon atoms). ｂR each independently represents a saturated alicyclic hydrocarbon group (having, for example, 4 or more, 6 or more, or 7 or more carbon atoms) or an unsaturated alicyclic hydrocarbon group (having, for example, 4 or more, 6 or more, or 7 or more carbon atoms), preferably a saturated alicyclic hydrocarbon group (having, for example, 6 (cyclohexane group) or 7 (norbornane group)). ａ and R ｂ may each independently have a substituent or may not have a substituent. Examples of the substituent include a substituent containing a heteroatom, and in the present disclosure, examples of the substituent containing a heteroatom are as described above. ａ and R ｂ The upper limit of the number of carbon atoms in R is, for example, 48 or less, 44 or less, 40 or less, or 36 or less. L represents a single bond or a linking group containing a heteroatom (excluding imide groups and amic acid groups). In the present disclosure, examples of linking groups containing a heteroatom represented by L are as described above. R ｅ R each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic compound group, preferably an aromatic hydrocarbon group, more preferably a benzene group. ｅ may each independently have a substituent or may not have a substituent. ｅ Examples of the substituent that R may have include a non-aromatic hydrocarbon group and a substituent containing a hetero atom. The non-aromatic hydrocarbon group is, for example, an alkyl group having 1 to 3 carbon atoms. ｆ represents a linear or branched saturated aliphatic hydrocarbon group, or a linear or branched unsaturated aliphatic hydrocarbon group. ｆ The number of carbon atoms in the group represented by formulae (GA1) to (GA3b) is, for example, 1 to 12, 2 to 8, or 3 to 6. However, the groups represented by formulae (GA1) to (GA3b) each include a substituent and R ｆ or both of which contain at least one non-aromatic hydrocarbon group (the total number of carbon atoms is, for example, 1 to 12, 2 to 8, or 3 to 6). For example, the block copolymer may contain a group represented by formula (GA3a) (where L is a single bond, R ｅ or one or both of which have a non-aromatic hydrocarbon group as a substituent) can introduce a rigid structure into the polyimide while increasing the free volume.

[0051] In some embodiments, when the hydrocarbon group (X) contains an aromatic ring group, the total number of carbon atoms in the non-aromatic hydrocarbon group may be greater than the total number of carbon atoms in the aromatic ring group, from the viewpoint of a low dielectric constant and a low dielectric loss tangent. The total number of carbon atoms in the aromatic ring group is, for example, 12 or less or 6 or less.

[0052] In some embodiments, when the hydrocarbon group (X) contains an unsaturated aliphatic hydrocarbon group having a small number of carbon atoms, such as 1, 2, or 3, and an aromatic ring group, the number of unsaturated aliphatic hydrocarbon groups may be 2 or more. In this case, the total number of carbon atoms in the non-aromatic hydrocarbon groups may be smaller than the total number of carbon atoms in the aromatic ring groups.

[0053] In some embodiments, the hydrocarbon group (X) includes at least one selected from the group consisting of a group represented by the following formula (G7), a group represented by the following formula (G8), and a group represented by the following formula (G9). These groups can be introduced into the block copolymer by using, for example, dimer diamine or dimer diisocyanate as a monomer for obtaining the block copolymer. The hydrocarbon group (X) preferably includes a group represented by formula (G8). When the structural unit (X) includes at least one selected from the group consisting of a group represented by formula (G7), a group represented by formula (G8), and a group represented by formula (G9), sufficient effects of low dielectric constant and low dielectric loss tangent tend to be easily obtained.

[0054]

[0055] In the formula, R ｃ each independently represents a linear alkylene group (having, for example, 6 or more, 8 or more, or 9 or more carbon atoms) or a linear alkenylene group (having, for example, 6 or more, 8 or more, or 9 or more carbon atoms); R ｄ R each independently represents a linear alkyl group (having, for example, 6 or more, 8 or more, or 9 or more carbon atoms) or a linear alkenyl group (having, for example, 6 or more, 8 or more, or 9 or more carbon atoms). ｃ and R ｄ may each independently have a substituent or may not have a substituent. ｃ and R ｄThe upper limit of the number of carbon atoms is, for example, 48 or less, 44 or less, 40 or less, or 36 or less.

[0056] In some embodiments, the hydrocarbon group (X) includes at least one selected from the group consisting of a group represented by the following formula (GA4) and a group represented by the following formula (GA5): The hydrocarbon group (X) preferably includes a group represented by formula (GA4): When the structural unit (X) includes at least one selected from the group consisting of a group represented by formula (GA4) and a group represented by formula (GA5), the effects of a low dielectric constant, a low dielectric loss tangent, and a low thermal expansion coefficient tend to be more easily obtained.

[0057]

[0058] In the formula, R ｄ R each independently represents a linear alkyl group (having, for example, 1 or more, 2 or more, or 3 or more carbon atoms) or a linear alkenyl group (having, for example, 2 or more, 3 or more, or 4 or more carbon atoms). ｄ may each independently have a substituent or may not have a substituent. ｄ The upper limit of the number of carbon atoms is, for example, 12 or less, 8 or less, or 6 or less.

[0059] (Organic Group (Y)) The structural unit (X) can contain an organic group (Y). The organic group (Y) is a group containing at least one aromatic ring group. Examples of the aromatic ring group include aromatic hydrocarbon groups and aromatic heterocyclic compound groups. The organic group (Y) is, for example, a group containing at least one selected from the group consisting of aromatic hydrocarbon groups, aromatic heterocyclic compound groups, and groups consisting of two or more selected from these. The organic group (Y) preferably contains an aromatic hydrocarbon group. The organic group (Y) may be an organic group that does not contain a non-aromatic hydrocarbon group. The organic group (Y) may further contain a non-aromatic hydrocarbon group, a linking group containing a heteroatom, a substituent containing a heteroatom, or the like. The organic group (Y) is, for example, a monovalent to tetravalent group. The structural unit (X) preferably contains a divalent to tetravalent organic group (Y), more preferably a divalent or tetravalent organic group (Y), and even more preferably a tetravalent organic group (Y).

[0060] The organic group (Y) preferably contains a group represented by the following formula (G11).

[0061]

[0062] In the formula, R ｙ represents an organic group (Y).

[0063] The organic group (Y) more preferably includes at least one selected from the group consisting of groups represented by the following formulae (G12) to (G14b):

[0064]

[0065] In the formula, R ｅ each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic compound group, preferably an aromatic hydrocarbon group, more preferably a benzene group. L represents a single bond or a linking group containing a hetero atom (excluding imide groups and amic acid groups). R ｅ may each independently have a substituent or may not have a substituent.

[0066] When the block copolymer has a group represented by formula (G12), the glass transition temperature of the polyimide tends to be improved. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G13) (L is a single bond) to a group represented by formula (G14b) (L is a single bond), a rigid structure can be introduced into the polyimide. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G13) (L is a linking group containing a heteroatom) to a group represented by formula (G14b) (L is a linking group containing a heteroatom), good solubility in solvents tends to be maintained. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G13) (L is an oxy group or a carbonyl group) to a group represented by formula (G14b) (L is an oxy group or a carbonyl group), an ether bond or a carbonyl bond can be introduced into the block chain, which tends to reduce the dielectric constant and dielectric loss tangent. The block copolymer may contain a group represented by formula (G14a) (L is an oxycarbonyl group) in place of or in addition to at least one selected from the group consisting of a group represented by formula (G13) (L is an oxy group or a carbonyl group) to a group represented by formula (G14b) (L is an oxy group or a carbonyl group).

[0067] Examples of the structural unit (X) include a structural unit represented by formula (XI) and a structural unit represented by formula (XA) described below. In a preferred embodiment, the structural unit (X) includes at least one selected from the group consisting of a structural unit represented by formula (XI) and a structural unit represented by formula (XA). Examples of the structural unit (X) include a structural unit (Xd) described below. In a preferred embodiment, the structural unit (X) includes the structural unit (Xd).

[0068] (Structural Unit (Y)) The block copolymer may contain a structural unit (Y). The structural unit (Y) is a structural unit different from the structural unit (X) contained in the block copolymer. The structural unit (Y) may have, for example, the above-mentioned organic group (Y). The structural unit (Y) may further contain at least one of an imide group and an amic acid group. For example, the structural unit (Y) is a structural unit containing an organic group (Y) and an imide group or an amic acid group. The block copolymer may contain the organic group (Y) contained in the structural unit (Y) and the imide group or the amic acid group in the polymer chain. The structural unit (Y) may contain one or more types of organic groups (Y).

[0069] In the structural unit (Y), the organic group (Y) preferably includes a group represented by the above formula (G11) and a group represented by the following formula (G15), and more preferably includes at least one selected from the group consisting of groups represented by the above formulas (G12) to (G14b) and at least one selected from the group consisting of groups represented by the following formulas (G16) to (G19):

[0070]

[0071] In the formula, R ｙ represents an organic group (Y). ｅ R each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic compound group, preferably an aromatic hydrocarbon group, more preferably a benzene group. ｅ may each independently have a substituent or may not have a substituent. ｅ Examples of the substituents that R may have include non-aromatic hydrocarbon groups and substituents containing heteroatoms. ｆ represents a linear or branched saturated aliphatic hydrocarbon group, or a linear or branched unsaturated aliphatic hydrocarbon group. ｆ The number of carbon atoms is, for example, 1 to 12, 2 to 8, or 3 to 6. L represents a single bond or a linking group containing a hetero atom (excluding imide groups and amic acid groups).

[0072] In some embodiments, when the organic group (Y) includes a non-aromatic hydrocarbon group, the total number of carbon atoms in the non-aromatic hydrocarbon group may be smaller than the total number of carbon atoms in the aromatic ring group, from the viewpoint of a low thermal expansion coefficient. The total number of carbon atoms in the non-aromatic hydrocarbon group is, for example, 8 or less, 6 or less, 4 or less, or 2 or less.

[0073] When the block copolymer has a group represented by formula (G16), the thermal expansion coefficient of the polyimide tends to be kept low. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G17) (L is a single bond) to a group represented by formula (G18b) (L is a single bond), a rigid structure can be introduced into the polyimide, and the thermal expansion coefficient tends to be small. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G17) (L is a linking group containing a heteroatom) to a group represented by formula (G18b) (L is a linking group containing a heteroatom), good solubility in solvents tends to be maintained. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G17) (L is an oxy group or a carbonyl group) to a group represented by formula (G18b) (L is an oxy group or a carbonyl group), an ether bond or a carbonyl bond can be introduced into the block chain. When the block copolymer has at least one group selected from the group consisting of a group represented by formula (G17) (L is a single bond, R ｅ or one or both of which have a non-aromatic hydrocarbon group as a substituent) can introduce a rigid structure into the polyimide while increasing the free volume.

[0074] Examples of the structural unit (Y) include a structural unit represented by the formula (YI) and a structural unit represented by the formula (YA) described below. In a preferred embodiment, the structural unit (Y) includes at least one selected from the group consisting of a structural unit represented by the formula (YI) and a structural unit represented by the formula (YA). Examples of the structural unit (Y) include a structural unit (Yd) described below. In a preferred embodiment, the structural unit (Y) includes the structural unit (Yd).

[0075] [Block Copolymer Comprising a Structural Unit Represented by Formula (I) and / or a Structural Unit Represented by Formula (A)] In some embodiments, the block copolymer comprises a polyimide block (BI) and a polyamic acid block (BA), and comprises a structural unit represented by the following formula (I) and a structural unit represented by the following formula (A), and has at least the following R Ａ and the following R Ｃ are different, or at least the following R Ｂ and the following R Ｄ is different from.

[0076] (Structural unit represented by formula (I))

[0077]

[0078] In the formula, R Ａ and R Ｂ each independently represents an organic group.

[0079] (Structural unit represented by formula (A))

[0080]

[0081] In the formula, R Ｃ and R Ｄ each independently represents an organic group.

[0082] Examples of the organic group include a hydrocarbon group (X) and an organic group (Y).

[0083] Examples of the structural unit represented by formula (I) include a structural unit represented by formula (XI) below and a structural unit represented by formula (YI) below. Examples of the structural unit represented by formula (A) include a structural unit represented by formula (XA) below and a structural unit represented by formula (YA) below. The polyimide block (BI) contains a structural unit represented by formula (I), and the polyamic acid block (BA) contains a structural unit represented by formula (A).

[0084] In some embodiments, the block copolymer comprises a polyimide block (BI) and a polyamic acid block (BA), and comprises at least one structural unit selected from the group consisting of a structural unit represented by the following formula (XI) and a structural unit represented by the following formula (XA): Examples of the block copolymer include a block copolymer in which the polyimide block (BI) comprises a structural unit represented by the formula (XI); a block copolymer in which the polyamic acid block (BA) comprises a structural unit represented by the formula (XA); and a block copolymer in which the polyimide block (BI) comprises a structural unit represented by the formula (XI) and the polyamic acid block (BA) comprises a structural unit represented by the formula (XA).

[0085] The block copolymer may contain a structural unit other than the structural unit represented by the following formula (XI) and the structural unit represented by the following formula (XA). Examples of structural units other than the structural unit represented by the following formula (XI) and the structural unit represented by the following formula (XA) include a structural unit represented by the formula (YI) and a structural unit represented by the formula (YA) described below. The block copolymer may contain at least one structural unit selected from the group consisting of a structural unit represented by the formula (YI) and a structural unit represented by the formula (YA). The structural unit represented by the formula (YI) and the structural unit represented by the formula (YA) may be a structural unit not having a hydrocarbon group (X).

[0086] The structural unit represented by formula (XI) and the structural unit represented by formula (XA) are structural units corresponding to the structural unit (X), and examples of the structural unit represented by formula (XI) and the structural unit represented by formula (XA) include the structural unit (Xd) described below. The structural unit represented by formula (YI) and the structural unit represented by formula (YA) are structural units corresponding to the structural unit (Y), and examples of the structural unit represented by formula (YI) and the structural unit represented by formula (YA) include the structural unit (Yd) described below.

[0087] (Structural unit represented by formula (XI))

[0088]

[0089] In the formula, R １ and R ２each independently represents an organic group; R １ and R ２ At least one of the groups is a hydrocarbon group (X).

[0090] Examples of the organic group include a hydrocarbon group (X) and an organic group (Y).

[0091] In the structural unit represented by formula (XI), for example, R １ is a hydrocarbon group (X), and R ２ is an organic group (Y); preferably, R １ is a group selected from the group consisting of groups represented by formula (G2) to groups represented by formula (G6), and R ２ is a group selected from the group consisting of groups represented by formula (G12) to groups represented by formula (G14b); more preferably, R １ is a group selected from the group consisting of a group represented by (G4) and a group represented by formula (G7) to a group represented by formula (G9), and R ２ is a group selected from the group consisting of groups represented by formula (G12) and groups represented by formula (G13); more preferably, R １ is a group represented by formula (G8), and R ２ is a group represented by formula (G13); particularly preferably, R １ is a group represented by formula (G8), and R ２ is a group represented by formula (G13) (for example, in the formula, R ｅ is a benzene group and L is a carbonyl group).

[0092] (Structural unit represented by formula (XA))

[0093]

[0094] In the formula, R ３ and R ４ each independently represents an organic group; R ３ and R ４ At least one of the groups is a hydrocarbon group (X).

[0095] Examples of the organic group include a hydrocarbon group (X) and an organic group (Y).

[0096] In the structural unit represented by formula (XA), for example, R３ is a hydrocarbon group (X), and R ４ is an organic group (Y); preferably, R ３ is a group selected from the group consisting of groups represented by formula (G2) to groups represented by formula (G6), and R ４ is a group selected from the group consisting of groups represented by formula (G12) to groups represented by formula (G14b); more preferably, R ３ is a group selected from the group consisting of a group represented by (G4) and a group represented by formula (G7) to a group represented by formula (G9), and R ４ is a group selected from the group consisting of groups represented by formula (G12) and groups represented by formula (G13); more preferably, R ３ is a group represented by formula (G8), and R ４ is a group represented by formula (G13); particularly preferably, R ３ is a group represented by formula (G8), and R ４ is a group represented by formula (G13) (for example, in the formula, R ｅ is a benzene group and L is a carbonyl group).

[0097] In the structural unit represented by formula (XA), for example, R ３ is a hydrocarbon group (X), and R ４ is an organic group (Y); preferably, R ３ is a group selected from the group consisting of groups represented by formulas (GA1) to (GA3b), and R ４ is a group selected from the group consisting of groups represented by formula (G12) to groups represented by formula (G14b); more preferably, R ３ is a group represented by (GA3a), and R ４ is a group selected from the group consisting of groups represented by formula (G13) and groups represented by formula (G14a); more preferably, R ３ is a group selected from the group consisting of groups represented by formula (GA4) and groups represented by formula (GA5), and R ４ is a group selected from the group consisting of groups represented by formula (G13) and groups represented by formula (G14a); particularly preferably, R ３ is a group represented by formula (GA4), and R ４ is a group represented by formula (G13) (for example, in the formula, Rｅ is a benzene group and L is a single bond) and a group represented by formula (G14a) (for example, in the formula, R ｅ is a benzene group, and L is a carbonyl group.

[0098] (Structural unit represented by formula (YI))

[0099]

[0100] In the formula, R ５ and R ６ each independently represents an organic group (Y).

[0101] In the structural unit represented by formula (YI), for example, R ５ is a group selected from the group consisting of groups represented by formula (G16) to groups represented by formula (G19), and R ６ is a group selected from the group consisting of groups represented by formula (G12) to groups represented by formula (G14b); preferably, R ５ is a group represented by formula (G16), a group represented by formula (G17), or a group represented by formula (G18), and R ６ is a group represented by formula (G12) or a group represented by formula (G13); more preferably, R ５ is a group represented by formula (G16) (for example, in the formula, R ｅ is a benzene group), a group represented by formula (G17) (for example, in the formula, R ｅ is a benzene group), or a group represented by formula (G18b) (for example, in the formula, R ｅ is a benzene group, and L is an oxy group, and R ６ is a group represented by formula (G12) (for example, in the formula, R ｅ is a benzene group) or a group represented by formula (G13) (for example, in the formula, R ｅ is a benzene group and L is a single bond).

[0102] (Structural unit represented by formula (YA))

[0103]

[0104] In the formula, R ７ and R ８each independently represents an organic group (Y).

[0105] In the structural unit represented by formula (YA), for example, R ７ is a group selected from the group consisting of groups represented by formula (G16) to groups represented by formula (G19), and R ８ is a group selected from the group consisting of groups represented by formula (G12) to groups represented by formula (G14b); preferably, R ７ is a group represented by formula (G16), a group represented by formula (G17), or a group represented by formula (G18a), and R ８ is a group represented by formula (G12) or a group represented by formula (G13); more preferably, R ７ is a group represented by formula (G16) (for example, in the formula, R ｅ is a benzene group), a group represented by formula (G17) (for example, in the formula, R ｅ is a benzene group), or a group represented by formula (G18b) (for example, in the formula, R ｅ is a benzene group, and L is an oxy group, and R ８ is a group represented by formula (G12) (for example, in the formula, R ｅ is a benzene group) or a group represented by formula (G13) (for example, in the formula, R ｅ is a benzene group and L is a single bond).

[0106] (Example of Block Copolymer) In a preferred embodiment, the block copolymer satisfies one or more of the following: The block copolymer contains a structural unit represented by formula (XI) (where R １ and R ２ is the group (X), and the at least one non-aromatic hydrocarbon group has a total carbon number of 9 or more. ３ and R ４ At least one of the structural units represented by formula (YI) (wherein R ５ and R ６are each independently a group containing an aromatic hydrocarbon group; and a structural unit represented by formula (YA) (wherein R ７ and R ８ are each independently a group containing an aromatic hydrocarbon group. １ is the group (X).) and a structural unit represented by formula (XA) (wherein R ３ is the group (X). ５ is a group containing an aromatic hydrocarbon group, and a structural unit represented by formula (YA) (wherein R ７ is a group containing an aromatic hydrocarbon group.) The block copolymer contains at least one structural unit represented by formula (XI) (wherein R １ is the group (X).) and a structural unit represented by formula (YA) (wherein R ７ is a group containing an aromatic hydrocarbon group.) The block copolymer contains a structural unit represented by formula (YI) (wherein R ５ is a group containing an aromatic hydrocarbon group, and a structural unit represented by formula (XA) (wherein R ３ is the group (X). The block copolymer contains a structural unit represented by formula (XI) (where R １ is the group (X).) and a structural unit represented by formula (XA) (wherein R ３ is the group (X). The polyimide block (BI) preferably contains a structural unit represented by formula (XI), and more preferably contains a structural unit represented by formula (XI) in which the hydrocarbon group (X) contains a saturated alicyclic hydrocarbon group. The polyamic acid block (BA) preferably contains a structural unit represented by formula (YA), and more preferably contains a structural unit represented by formula (YA) in which the organic group (Y) contains an aromatic hydrocarbon group.

[0107] (Content, etc.) In the polyimide block (BI), the content of the hydrocarbon group (X) is １ ~R ８ The content of the hydrocarbon group (X) is preferably 0 to 70 mass %, 10 to 60 mass %, or 20 to 50 mass % based on the total mass of the above. In particular, when the content of the hydrocarbon group (X) is 20 mass % or more, a polyimide having a low dielectric constant and a low dielectric loss tangent is likely to be obtained. In the polyimide block (BI), the content of the organic group (Y) is preferably 0 to 70 mass %, 10 to 60 mass %, or 20 to 50 mass % based on the total mass of the above. １ ~R ８ The content of the organic group (Y) containing an aromatic hydrocarbon group is preferably 0 to 60 mass %, 2 to 50 mass %, or 4 to 40 mass % based on the total mass of the blocks and polymers. In particular, when the content of the organic group (Y) containing an aromatic hydrocarbon group is 4 mass % or more, a polyimide having a low thermal expansion coefficient is likely to be obtained. In the present disclosure, depending on the structure contained in the block or polymer, １ ~R ８ R in "total mass" １ ~R ８ The mass of any one or more of the above may be zero.

[0108] In the polyamic acid block (BA), the content of the hydrocarbon group (X) is R １ ~R ８ In the polyamic acid block (BA), the content of the organic group (Y) is preferably 0 to 80 mass %, 0 to 50 mass %, or 0 to 30 mass % based on the total mass of R １ ~R ８ In particular, when the content of the organic group (Y) containing an aromatic hydrocarbon group is 40 mass % or more, a polyimide having a low thermal expansion coefficient is likely to be obtained.

[0109] In the block copolymer, the content of the hydrocarbon group (X) is R １ ~R ８The content of the hydrocarbon group (X) is preferably 5 to 70 mass %, 10 to 60 mass %, or 20 to 50 mass %, based on the total mass of the components (a) and (b). From the viewpoint of reducing the dielectric constant and the dielectric loss tangent, it is preferable that the content of the hydrocarbon group (X) is large. In particular, when the content of the hydrocarbon group (X) is 10 mass % or more, a polyimide having a low dielectric constant and a low dielectric loss tangent is likely to be obtained.

[0110] In the block copolymer, the content of the organic group (Y) is １ ~R ８ The content of the organic group (Y) is preferably 30 to 95 mass %, 40 to 90 mass %, or 50 to 80 mass %, based on the total mass of the components. From the viewpoint of obtaining a low coefficient of thermal expansion, the organic group (Y) preferably contains an aromatic hydrocarbon group, and the content of such organic group (Y) is preferably high. In particular, when the content of the organic group (Y) containing an aromatic hydrocarbon group is 50 mass % or more, a polyimide having a low coefficient of thermal expansion is likely to be obtained.

[0111] For example, R １ ~R ８ contains a group corresponding only to the hydrocarbon group (X) (e.g., group 14 in Table 1) and a group corresponding to both the hydrocarbon group (X) and the organic group (Y) (e.g., group 5 in Table 1), the content of the hydrocarbon group (X) can be used as the content of "groups corresponding only to the hydrocarbon group (X)", and the content of the organic group (Y) can be used as the content of "groups corresponding to both the hydrocarbon group (X) and the organic group (Y)". １ ~R ８contains a group corresponding to both the hydrocarbon group (X) and the organic group (Y) (e.g., group 5 in Table 1), and a group corresponding only to the organic group (Y) (e.g., group 1 in Table 1), the content of the hydrocarbon group (X) can be defined as the content of "groups corresponding to both the hydrocarbon group (X) and the organic group (Y)," and the content of the organic group (Y) can be defined as the content of "groups corresponding only to the organic group (Y)." Alternatively, for example, by distinguishing based on the number of carbon atoms in the non-aromatic hydrocarbon group, the content of the hydrocarbon group (X) can be defined as the content of "hydrocarbon groups (X) in which the total number of carbon atoms in the non-aromatic hydrocarbon groups is n or more (e.g., 9 or more)," and the content of the organic group (Y) can be defined as the content of "organic groups (Y) in which the total number of carbon atoms in the non-aromatic hydrocarbon groups is n-1 or less (e.g., 0 to 8)."

[0112] (Optional Structural Unit) The block copolymer may further contain other optional structural units in addition to the structural units represented by formula (I) and the structural units represented by formula (A). The content of the other optional structural units in the block copolymer is, for example, 0 to 10% by mass, or 0 to 5% by mass, based on the total mass of all structural units contained in the block copolymer. Examples of the other optional structural units include structural units containing a structure derived from a trifunctional or higher polyamine or a structure derived from a trifunctional or higher polyisocyanate, a structural unit having an amide bond (also referred to as an amide group), a structural unit having an imide group and an amide group, and a structural unit having an amic acid group and an amide group. These optional structural units may or may not contain a hydrocarbon group (X).

[0113] [Block Copolymer Comprising a Structure Derived from a Diamine or a Diisocyanate and a Structure Derived from a Tetracarboxylic Dianhydride] In some embodiments, the block copolymer comprises a polyimide block (BI) and a polyamic acid block (BA), and has a structure derived from a diamine or a diisocyanate and a structure derived from a tetracarboxylic dianhydride.

[0114] In some embodiments, at least one of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride includes a structure having a hydrocarbon group (X). Examples of the structure having a hydrocarbon group (X) include a structure derived from a diamine or diisocyanate having a hydrocarbon group (X) and a structure derived from a tetracarboxylic dianhydride having a hydrocarbon group (X). In the present disclosure, "diamine or diisocyanate" means "at least one compound selected from the group consisting of diamines and diisocyanates."

[0115] In some embodiments, the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride include a structure having an organic group (Y). Examples of the structure having an organic group (Y) include a structure derived from a diamine or diisocyanate having an organic group (Y) and a structure derived from a tetracarboxylic dianhydride having an organic group (Y).

[0116] In the present disclosure, a structural unit having a structure derived from a diamine or diisocyanate and a structure derived from a tetracarboxylic dianhydride, in which at least one of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride contains a structure having a hydrocarbon group (X), may be referred to as a "structural unit (Xd)".

[0117] (Diamine Having Hydrocarbon Group (X)) The diamine having a hydrocarbon group (X) can be represented by, for example, the following formula (Ax).

[0118]

[0119] In the formula, R ｘ represents a hydrocarbon group (X). ｘ Examples of the group include the groups represented by the above formulae (G2) to (G9) and the groups represented by the formulae (GA1) to (GA3b).

[0120] Specific examples of diamines having a hydrocarbon group (X) include the following: diamines having a saturated aliphatic hydrocarbon group, such as 1,2-ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,14-diaminotetradecane, and 1,16-diaminohexadecane; diamines having an unsaturated aliphatic hydrocarbon group, such as 1,9-diaminononene, 1,10-diaminodecene, 1,11-diaminoundecene, 1,12-diaminododecene, 1,14-diaminotetradecene, and 1,16-diaminohexadecane; Diamines having a saturated alicyclic hydrocarbon group, such as 1,4-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, isophoronediamine, bis(aminomethyl)norbornane, 1,3-diaminoadamantane, and 4,4'-diaminodicyclohexylmethane; Diamines having an unsaturated alicyclic hydrocarbon group, such as bis(aminomethyl)norbornene and 4,4'-diaminodicyclohexenylmethane; Monounsaturated fatty acids such as crotonic acid, myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, gadoleic acid, eicosenoic acid, erucic acid, and nervonic acid; diunsaturated fatty acids such as linoleic acid, eicosadienoic acid, and docosadienoic acid; and dimers of unsaturated fatty acids (also called dimer acids), such as triunsaturated fatty acids such as linolenic acid, pinolenic acid, eleostearic acid, mead acid, dihomo-γ-linolenic acid, and eicosatrienoic acid.and dimer diamines such as diamines which are compounds in which the carbon-carbon double bonds contained in the molecule of these diamines have been hydrogenated; diamines having a non-aromatic hydrocarbon group and an aromatic hydrocarbon group, such as 4,4'-diamino-2,2'-dimethylbiphenyl (m-tolidine), 4,4'-diamino-3,3'-dimethylbiphenyl, 4,4'-diamino-3,3'-dimethyldiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diaminodiphenylpropane, and 2,2-bis(4-(4-aminophenoxy)phenyl)propane.

[0121] Commercially available dimer diamine products include, for example, "PRIAMINE 1075" and "PRIAMINE 1074" manufactured by Croda Japan Co., Ltd.

[0122] (Diamine Having Organic Group (Y)) The diamine having the organic group (Y) can be represented by, for example, the following formula (Ay).

[0123]

[0124] In the formula, R ｙ represents an organic group (Y). ｙ Examples of the group include the groups represented by the above formulae (G16) to (G19).

[0125] Specific examples of diamines having an organic group (Y) include the following: Diamines having an aromatic hydrocarbon group but no non-aromatic hydrocarbon group, such as 1,4-phenylenediamine, 4,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, and 4,4'-bis(4-aminophenoxy)biphenyl; and diamines having a non-aromatic hydrocarbon group and an aromatic hydrocarbon group, such as those exemplified above.

[0126] (Diisocyanate Having Hydrocarbon Group (X)) The diisocyanate having a hydrocarbon group (X) can be represented, for example, by the following formula (Ix).

[0127]

[0128] In the formula, Rｘ represents a hydrocarbon group (X). ｘ Examples of the group include the groups represented by the above formulae (G2) to (G9) and the groups represented by the formulae (GA1) to (GA3b).

[0129] Specific examples of diisocyanates having a hydrocarbon group (X) include compounds having the same structure as the compounds shown as specific examples of the diamines above, except that the amino group is replaced with an isocyanate group.

[0130] (Diisocyanate Having Organic Group (Y)) The diisocyanate having the organic group (Y) can be represented by, for example, the following formula (Iy).

[0131]

[0132] In the formula, R ｙ represents an organic group (Y). ｙ Examples of the group include the groups represented by the above formulae (G16) to (G19).

[0133] Specific examples of diisocyanates having an organic group (Y) include compounds having the same structure as the compounds shown as specific examples of diamines above, except that the amino group is replaced with an isocyanate group.

[0134] (Tetracarboxylic acid dianhydride having hydrocarbon group (X)) The tetracarboxylic acid dianhydride having hydrocarbon group (X) can be represented by, for example, the following formula (Cx).

[0135]

[0136] In the formula, R ｘ represents a hydrocarbon group (X). Preferred examples of the hydrocarbon group (X) are as described above.

[0137] Specific examples of tetracarboxylic acid dianhydrides having a hydrocarbon group (X) include the following. When counting the number of carbon atoms in the hydrocarbon group (X) of a tetracarboxylic acid dianhydride, the "number of carbon atoms" does not include the number of carbon atoms contained in the carboxylic acid anhydride group. Tetracarboxylic acid dianhydrides having a saturated aliphatic hydrocarbon group, such as 1,2,3,4-butanetetracarboxylic acid dianhydride and 1,2,5,6-hexanetetracarboxylic acid dianhydride; Tetracarboxylic acid dianhydrides having an alicyclic hydrocarbon group, such as 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,3',4,4'-bicyclohexyltetracarboxylic acid dianhydride and 2,2-bis(3,4-dicarboxycyclohexyl)propane dianhydride; Tetracarboxylic acid dianhydrides having an aromatic hydrocarbon group and a non-aromatic hydrocarbon group, such as bis(2,3-dicarboxyphenyl)methane dianhydride and bis(3,4-dicarboxyphenyl)methane dianhydride.

[0138] (Tetracarboxylic acid dianhydride having organic group (Y)) The tetracarboxylic acid dianhydride having organic group (Y) can be represented by, for example, the following formula (Cy).

[0139]

[0140] In the formula, R ｙ represents an organic group (Y). ｙ Examples of the group include the groups represented by the above formulae (G12) to (G14b).

[0141] Specific examples of tetracarboxylic acid dianhydrides having an organic group (Y) include the following: tetracarboxylic acid dianhydrides having an aromatic hydrocarbon group but not a non-aromatic hydrocarbon group, such as pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 4,4'-oxydiphthalic anhydride, 3,4'-oxydiphthalic anhydride, bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid)1,4-phenylene; tetracarboxylic acid dianhydrides having an aromatic heterocyclic compound group but not a non-aromatic hydrocarbon group, such as pyridine tetracarboxylic acid dianhydride and thiophene tetracarboxylic acid dianhydride; and tetracarboxylic acid dianhydrides having an aromatic hydrocarbon group and a non-aromatic hydrocarbon group, such as those exemplified above.

[0142] (Examples of Block Copolymer) In a preferred embodiment, the block copolymer satisfies any one or more of the following: In the block copolymer, the structure derived from a diamine or diisocyanate preferably includes a structure derived from a diamine or diisocyanate having a hydrocarbon group (X); more preferably includes at least one selected from the group consisting of a structure derived from a diamine or diisocyanate having a saturated aliphatic hydrocarbon group, a structure derived from a diamine or diisocyanate having an unsaturated aliphatic hydrocarbon group, a structure derived from a diamine or diisocyanate having a saturated alicyclic hydrocarbon group, a structure derived from a diamine or diisocyanate having an unsaturated alicyclic hydrocarbon group, and a structure derived from dimer diamine or dimer diisocyanate; and even more preferably includes a structure derived from dimer diamine or dimer diisocyanate.

[0143] The block copolymer preferably includes a structure derived from a diamine or diisocyanate having a hydrocarbon group (X) derived from a diamine or diisocyanate having at least one non-aromatic hydrocarbon group with a total carbon number of 9 or more; more preferably includes at least one selected from the group consisting of a structure derived from a diamine or diisocyanate having a saturated aliphatic hydrocarbon group with 9 or more carbon atoms, a structure derived from a diamine or diisocyanate having an unsaturated aliphatic hydrocarbon group with 9 or more carbon atoms, a structure derived from a diamine or diisocyanate having a saturated alicyclic hydrocarbon group with 9 or more carbon atoms, a structure derived from a diamine or diisocyanate having an unsaturated alicyclic hydrocarbon group with 9 or more carbon atoms, and a structure derived from a dimer diamine or diisocyanate having 9 or more carbon atoms; and even more preferably includes a structure derived from a dimer diamine or diisocyanate having 9 or more carbon atoms. The diamine or diisocyanate-derived structure may include a structure derived from m-tolidine.

[0144] In the block copolymer, the structure derived from a diamine or diisocyanate preferably includes a structure derived from dimer diamine or dimer diisocyanate and a structure derived from a diamine or diisocyanate having a saturated aliphatic hydrocarbon group (excluding dimer diamine or dimer diisocyanate); more preferably, it includes a structure derived from a dimer diamine or dimer diisocyanate having 9 or more carbon atoms and a structure derived from m-tolidine.

[0145] In the block copolymer, the structure derived from a tetracarboxylic dianhydride preferably includes a structure derived from a tetracarboxylic dianhydride having an organic group (Y); more preferably includes a structure derived from a tetracarboxylic dianhydride having an aromatic hydrocarbon group; and even more preferably includes at least one structure selected from the group consisting of a structure derived from pyromellitic dianhydride, a structure derived from 3,3',4,4'-benzophenonetetracarboxylic dianhydride, and a structure derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride.

[0146] The block copolymer includes a structure in which at least one of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride has a group (X) containing at least one non-aromatic hydrocarbon group, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more. The block copolymer includes a structure in which the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride has a structure in which the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride has an organic group (Y) wherein the aromatic ring group is an aromatic hydrocarbon group.

[0147] In the block copolymer, for example, the structure derived from a diamine or diisocyanate contained in the polyimide block (BI) contains a structure having a group (X) containing at least one non-aromatic hydrocarbon group. In the block copolymer, for example, the structure derived from a diamine or diisocyanate contained in the polyamic acid block (BA) contains a structure derived from a diamine or diisocyanate having an organic group (Y). In the block copolymer, for example, both the structure derived from a diamine or diisocyanate contained in the polyimide block (BI) and the structure derived from a diamine or diisocyanate contained in the polyamic acid block (BA) contain a structure having a group (X) containing at least one non-aromatic hydrocarbon group.

[0148] The block copolymer includes at least a structure derived from a diamine or diisocyanate, which includes a structure derived from a diamine or diisocyanate having a hydrocarbon group (X) and a structure having an organic group (Y) in which the aromatic ring group is an aromatic hydrocarbon group. The block copolymer includes a structure derived from dimer diamine or dimer diisocyanate. The block copolymer includes a structure derived from m-tolidine. The block copolymer includes a structure derived from at least one selected from the group consisting of 4,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-diisocyanatodiphenyl ether, 1,4-bis(4-isocyanatophenoxy)benzene, and 4,4'-bis(4-isocyanatophenoxy)biphenyl.

[0149] (Content, etc.) In the polyimide block (BI), the content of the structure having a hydrocarbon group (X) is, for example, 0 to 95% by mass, preferably 40 to 95% by mass, 50 to 95% by mass, or 70 to 90% by mass, based on the total mass of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride. In particular, when the content of the structure having a hydrocarbon group (X) is 70% by mass or more, a polyimide having a low dielectric constant and a low dielectric dissipation factor is likely to be obtained. In the polyimide block (BI), the content of the structure having an organic group (Y) is, for example, 5 to 100% by mass, preferably 5 to 60% by mass, 5 to 50% by mass, or 10 to 30% by mass, based on the total mass of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride. In particular, when the content of the structure having an organic group (Y) containing an aromatic hydrocarbon group is 10% by mass or more, a polyimide having a low thermal expansion coefficient is likely to be obtained.

[0150] In the polyamic acid block (BA), the content of the structure having a hydrocarbon group (X) is preferably 0 to 60 mass%, 10 to 50 mass%, or 20 to 40 mass%, based on the total mass of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride. In particular, when the content of the structure having a hydrocarbon group (X) is 10 mass% or more, a polyimide having a low dielectric constant and a low dielectric dissipation factor is easily obtained. In the polyamic acid block (BA), the content of the structure having an organic group (Y) is preferably 30 to 100 mass%, 50 to 95 mass%, or 70 to 90 mass%, based on the total mass of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride. In particular, when the content of the structure having an organic group (Y) containing an aromatic hydrocarbon group is 70 mass% or more, a polyimide having a low thermal expansion coefficient is easily obtained.

[0151] In the block copolymer, the content of the structure having a hydrocarbon group (X) is preferably 3 to 60 mass%, 5 to 50 mass%, or 10 to 40 mass%, based on the total mass of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride. From the viewpoint of reducing the dielectric constant and the dielectric loss tangent, a large content of the structure having a hydrocarbon group (X) is preferred. In particular, when the content of the structure having a hydrocarbon group (X) is 5 mass% or more, a polyimide having a low dielectric constant and a low dielectric loss tangent is likely to be obtained.

[0152] In the block copolymer, the content of the structure having an organic group (Y) is preferably 40 to 97% by mass, 50 to 95% by mass, or 60 to 90% by mass, based on the total mass of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride. From the viewpoint of obtaining a low thermal expansion coefficient, the organic group (Y) preferably contains an aromatic hydrocarbon group, and the content of such a structure having an organic group (Y) is preferably high. In particular, when the content of the structure having an organic group (Y) containing an aromatic hydrocarbon group is 50% by mass or more, a polyimide having a low thermal expansion coefficient is likely to be obtained.

[0153] The content of the structure having the hydrocarbon group (X) and the content of the structure having the organic group (Y) are also determined by the formula R １ ~R ８ Similarly, the non-aromatic hydrocarbon groups may be classified into "a group corresponding only to the hydrocarbon group (X)," "a group corresponding to both the hydrocarbon group (X) and the organic group (Y)," "a group corresponding only to the organic group (Y)," or the like, or may be classified based on the number of carbon atoms in the non-aromatic hydrocarbon group and applied to the block copolymer.

[0154] (Optional Structure) The block copolymer may further contain another optional structure in addition to the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride. In the block copolymer, the content of the other optional structural unit is, for example, 0 to 10% by mass or 0 to 5% by mass based on the total mass of all structures contained in the block copolymer. The other optional structure may include an optional structure derived from a tri- or higher functional polyamine or polyisocyanate, a structure derived from a dicarboxylic acid compound, or a structure derived from a tricarboxylic acid compound. These optional structures may or may not contain a hydrocarbon group (X).

[0155] [Block Copolymer Obtained Using Diamine or Diisocyanate and Tetracarboxylic Acid Dianhydride] In some embodiments, the block copolymer is obtained using a polyimide (PI) obtained using a diamine or diisocyanate and a tetracarboxylic acid dianhydride, and a polyamic acid (PA) obtained using a diamine and a tetracarboxylic acid dianhydride. In some embodiments, at least one selected from the group consisting of the diamine or diisocyanate and the tetracarboxylic acid dianhydride used to obtain the polyimide (PI) and the diamine and the tetracarboxylic acid dianhydride used to obtain the polyamic acid (PA) may have a hydrocarbon group (X). Methods for obtaining the polyimide (PI), the polyamic acid (PA), and the block copolymer will be described later.

[0156] [Polyimide Block (BI)] When the block copolymer has the polyimide block (BI), it is possible to prevent an exchange reaction or crosslinking from occurring when the block copolymer is obtained or when the amide acid group is ring-closed.

[0157] In the present disclosure, the polyimide block (BI) has an imide group content relative to the total of imide groups and amic acid groups of, for example, more than 50 mol%, 80 mol% or more, or 90 mol% or more. The upper limit of the imide group content may be 100 mol%. In the present disclosure, the content can be measured by Fourier Transform Infrared Spectroscopy (FTIR).

[0158] The polyimide block (BI) may or may not contain the structural unit (X). For example, in a block copolymer, when the polyimide block (BI) does not contain the structural unit (X), the polyimide block (BI) contains the structural unit (Y). For example, in a block copolymer, when the polyimide block (BI) does not contain the structural unit (X), the polyamic acid block (BA) contains the structural unit (X).

[0159] The number average molecular weight of the polyimide block (BI) is, for example, 500 or more, 1,000 or more, 2,000 or more, or 3,000 or more. The number average molecular weight of the polyimide block (BI) is, for example, 10,000 or less, 8,000 or less, 7,000 or less, or 5,000 or less. A number average molecular weight of 500 or more tends to make it easier to obtain a polyimide with a low thermal expansion coefficient. A number average molecular weight of 10,000 or less tends to make it easier to ensure the solubility of the block copolymer in a solvent. The number average molecular weight of the polyimide block (BI) is, for example, 500 to 10,000, 1,000 to 8,000, 2,000 to 7,000, or 3,000 to 5,000. In the present disclosure, the number average molecular weight can be measured by gel permeation chromatography (GPC) using a calibration curve of standard polystyrene. Specifically, it can be determined by the method described in the Examples.

[0160] The polyimide block (BI) may be a linear polymer block or a branched polymer block, and is preferably a linear polymer block.

[0161] [Polyamic Acid Block (BA)] When the block copolymer contains a polyamic acid block, it tends to have good solubility in a solvent.

[0162] In the present disclosure, the polyamic acid block (BA) has a content of amic acid groups relative to the total of imide groups and amic acid groups of, for example, more than 50 mol%, 80 mol% or more, or 90 mol% or more. The upper limit of the content of amic acid groups may be 100 mol%. The content can be measured by FTIR.

[0163] The polyamic acid block (BA) may or may not contain the structural unit (X). For example, in a block copolymer, when the polyamic acid block (BA) does not contain the structural unit (X), the polyamic acid block (BA) contains the structural unit (Y). For example, in a block copolymer, when the polyamic acid block (BA) does not contain the structural unit (X), the polyimide block (BI) contains the structural unit (X).

[0164] The number average molecular weight of the polyamic acid block (BA) is, for example, 500 or more, 1,000 or more, 3,000 or more, or 4,000 or more. The number average molecular weight of the polyamic acid block (BA) is, for example, 30,000 or less, 25,000 or less, 20,000 or less, or 10,000 or less. A number average molecular weight of 500 or more tends to make it easier to obtain good film-forming properties. A number average molecular weight of 30,000 or less tends to make it easier to adjust the viscosity of a composition containing a block copolymer and a solvent to a level suitable for application. The number average molecular weight of the polyamic acid block (BA) is, for example, 500 to 30,000, 1,000 to 25,000, 3,000 to 20,000, or 4,000 to 10,000.

[0165] The polyamic acid block (BA) may be a linear polymer block or a branched polymer block, and is preferably a linear polymer block.

[0166] [Molecular Weight of Block Copolymer, Content of Structural Unit (X), etc.] When the block copolymer contains a polyimide block (BI) and a polyamic acid block (BA), it is easy to obtain a polyimide that has a low dielectric constant, a low dielectric loss tangent, and a low thermal expansion coefficient. This is thought to be because the block structure makes it easier for polyimide molecules to be oriented.

[0167] In the block copolymer, either one of the polyimide block (BI) or the polyamic acid block (BA) contains a hydrocarbon group (X), or both the polyimide block (BI) and the polyamic acid block (BA) contain a hydrocarbon group (X). The polyimide block (BI) and the polyamic acid block (BA) may each independently contain one or more types of hydrocarbon groups (X). In the block copolymer, either one of the polyimide block (BI) or the polyamic acid block (BA) contains an organic group (Y), or both the polyimide block (BI) and the polyamic acid block (BA) contain an organic group (Y). The polyimide block (BI) and the polyamic acid block (BA) may each independently contain one or more types of organic groups (Y).

[0168] In the block copolymer, the organic group (Y) may be a group different from the hydrocarbon group (X) contained in the block copolymer. Using the groups in Table 1 as an example, a block copolymer having any one group selected from Groups 7 to 14 and any one group selected from Groups 1 to 3 is a block copolymer having a hydrocarbon group (X) and an organic group (Y). A block copolymer having any one group selected from Groups 7 to 14 and any one group selected from Groups 4 to 6 is a block copolymer having a hydrocarbon group (X) and an organic group (Y). A block copolymer having any one group selected from Groups 4 to 6 and any one group selected from Groups 1 to 3 is a block copolymer having a hydrocarbon group (X) and an organic group (Y). A block copolymer having Groups 6 and 4 is a block copolymer having a hydrocarbon group (X) and an organic group (Y).

[0169] The number average molecular weight of the block copolymer is, for example, 5,000 or more, 10,000 or more, 20,000 or more, or 30,000 or more. The number average molecular weight of the block copolymer is, for example, 100,000 or less, 80,000 or less, 70,000 or less, or 60,000 or less. A number average molecular weight of 5,000 or more tends to make it easier to obtain good film-forming properties. A number average molecular weight of 100,000 or less tends to make it easier to adjust the viscosity of a composition containing the block copolymer and a solvent to a level suitable for application. The number average molecular weight of the block copolymer is, for example, 5,000 to 100,000, 10,000 to 80,000, 20,000 to 70,000, or 30,000 to 60,000.

[0170] The content of the polyimide block (BI) in the block copolymer is greater than 0% by mass and less than 100% by mass, based on the mass of the block copolymer. The content of the polyimide block (BI) is, for example, greater than 0% by mass, 30% by mass or more, 60% by mass or more, or 90% by mass or more. The content of the polyimide block (BI) is, for example, less than 100% by mass, 70% by mass or less, 40% by mass or less, or 10% by mass or less. The content of the polyimide block (BI) is, for example, greater than 0% by mass and 70% by mass or less, greater than 0% by mass and 40% by mass or less, 30% by mass or more and less than 100% by mass, or 60% by mass or more and less than 100% by mass. The content of the polyimide block (BI) may be, for example, 30 to 70% by mass or 35 to 65% by mass.

[0171] The content of the polyamic acid block (BA) in the block copolymer is greater than 0% by mass and less than 100% by mass, based on the mass of the block copolymer. The content of the polyamic acid block (BA) is, for example, greater than 0% by mass, 30% by mass or more, 60% by mass or more, or 90% by mass or more. The content of the polyamic acid block (BA) is, for example, less than 100% by mass, 70% by mass or less, 40% by mass or less, or 10% by mass or less. The content of the polyamic acid block (BA) is, for example, greater than 0% by mass and 70% by mass or less, greater than 0% by mass and 40% by mass or less, 30% by mass or more and less than 100% by mass, or 60% by mass or more and less than 100% by mass. The content of the polyamic acid block (BA) may be, for example, 30 to 70% by mass or 35 to 65% by mass.

[0172] The higher the content of the polyimide block (BI), the more effectively it is possible to prevent exchange reactions and crosslinking when obtaining a block copolymer or when ring-closing an amic acid group.On the other hand, the higher the content of the polyamic acid block (BA), the more easily the block copolymer dissolves in an organic solvent.

[0173] In the block copolymer, for example, the number average molecular weight of the polyimide block (BI) is smaller than that of the polyamic acid block (BA). Preferably, the block copolymer contains a polyimide block (BI) and a polyamic acid block (BA) having a number average molecular weight larger than that of the polyimide block (BI). When the number average molecular weight of the polyimide block (BI) is smaller than that of the polyamic acid block (BA), the block copolymer is easy to synthesize and the solubility of the block copolymer tends to be ensured. By including a polyamic acid block (BA) having a number average molecular weight larger than that of the polyimide block (BI), a block copolymer having a sufficient number average molecular weight tends to be easy to synthesize.

[0174] The block copolymer is preferably such that a polyimide film obtained using the block copolymer satisfies one or more of the dielectric constant, dielectric loss tangent, and thermal expansion coefficient described below. Particularly preferably, the block copolymer is such that a polyimide film obtained using the block copolymer satisfies the dielectric constant and dielectric loss tangent described below, or satisfies the dielectric constant, dielectric loss tangent, and thermal expansion coefficient described below.

[0175] [Optional Components] In some embodiments, the antenna substrate material may further contain optional components such as a thermoplastic resin, an organic filler, a flame retardant, a flame retardant aid, an ultraviolet absorber, a peroxide, an antioxidant, a photopolymerization initiator, a fluorescent brightener, or an adhesion improver.

[0176] [Characteristics, Applications, etc.] In some embodiments, a polyimide material having a low dielectric constant, a low dielectric loss tangent, and a low coefficient of thermal expansion can be obtained by using an antenna substrate material. It is preferable that a polyimide film obtained by using the antenna substrate material satisfies one or more of the dielectric constant, dielectric loss tangent, and coefficient of thermal expansion described below. It is particularly preferable that a polyimide film obtained by using the antenna substrate material satisfies the dielectric constant and dielectric loss tangent described below, or satisfies the dielectric constant, dielectric loss tangent, and coefficient of thermal expansion described below.

[0177] <Method for Producing Antenna Substrate Material> In some embodiments, a method for producing an antenna substrate material containing a block copolymer includes obtaining a polyimide (PI) using a diamine or diisocyanate and a tetracarboxylic dianhydride; obtaining a polyamic acid (PA) using the diamine and the tetracarboxylic dianhydride; and obtaining a block copolymer using the polyimide (PI) and the polyamic acid (PA). In some embodiments, at least one selected from the group consisting of the diamine or diisocyanate and the tetracarboxylic dianhydride used to obtain the polyimide (PI) and the diamine and the tetracarboxylic dianhydride used to obtain the polyamic acid (PA) may have a hydrocarbon group (X). This production method makes it possible to easily produce the antenna substrate material of the above-mentioned embodiment.

[0178] For the synthesis of polyimide (PI) and polyamic acid (PA), monomers such as the above-mentioned diamines, diisocyanates, tetracarboxylic dianhydrides, polyamines, polyisocyanates, dicarboxylic acid compounds, and tricarboxylic acid compounds can be used.

[0179] The reaction of the monomers can be carried out by solution polymerization. Examples of the solvent used in the reaction include polar solvents such as N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone (NEP), γ-butyrolactone (GBL), N,N'-dimethylacetamide, 3-methoxy-N,N-dimethylpropanamide (MPA), N,N'-dimethylformamide, N,N'-dimethylpropyleneurea [1,3-dimethyl-3,4,5,6-tetrahydropyridimine-2(1H)-one], dimethyl sulfoxide, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and sulfolane; aromatic hydrocarbon solvents such as cyclohexanone, xylene, and toluene; and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. The solvent preferably contains at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone (NEP), γ-butyrolactone (GBL), and 3-methoxy-N,N-dimethylpropanamide (MPA), and more preferably contains at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), and 3-methoxy-N,N-dimethylpropanamide (MPA).

[0180] The amount of solvent used is preferably 100 to 600 parts by mass, and more preferably 200 to 500 parts by mass, per 100 parts by mass of the total amount of monomers. When the amount of solvent used is 100 parts by mass or more, the respective monomers can be reacted homogeneously. When the amount of solvent used is 600 parts by mass or less, the polymerization reaction can be promoted. Furthermore, when the amount of solvent used is small, a polyimide (PI) or polyamic acid (PA)-containing liquid containing polyimide (PI) or polyamic acid (PA) at a high concentration can be obtained.

[0181] The reaction temperature when synthesizing polyamic acid using monomers is not particularly limited. The reaction temperature may be, for example, 10 to 50°C, or 20 to 40°C. The reaction time may be, for example, 30 minutes to 24 hours, 1 to 12 hours, or 3 to 6 hours. The reaction product may be sampled to measure the number average molecular weight, the concentration of residual amino groups or isocyanate groups, etc., and the reaction time may be adjusted so as to obtain the desired reaction product.

[0182] The temperature when obtaining a polyimide using a polyamic acid (i.e., when imidizing) is not particularly limited. The imidization temperature may be, for example, 120 to 200°C, or 160 to 180°C. The reaction time may be, for example, 30 minutes to 24 hours, 1 to 12 hours, or 3 to 6 hours. The reaction product may be sampled to measure the number average molecular weight, the concentration of remaining amic acid groups, etc., and the reaction time may be adjusted so as to obtain the desired reaction product.

[0183] In view of ease of synthesis, it is preferred that the polymer chain of the polyimide (PI) be terminated with a carboxylic acid anhydride group, and the polymer chain of the polyamic acid (PA) be terminated with an amino group. The ratio of the diamine or diisocyanate to the tetracarboxylic acid dianhydride used to obtain the polyimide (PI) is, for example, more than 1.00 mol%, 1.05 mol% or more, or 1.10 mol% or more, based on the diamine or diisocyanate. The ratio of the diamine to the tetracarboxylic acid dianhydride used to obtain the polyamic acid (PA) is, for example, less than 1.00 mol%, 0.98 mol% or less, or 0.97 mol% or less, based on the diamine.

[0184] A block copolymer is synthesized using polyimide (PI) and polyamic acid (PA). Any other polymer may also be used in the synthesis.

[0185] The reaction between polyimide (PI) and polyamic acid (PA) can be carried out by solution polymerization. As the solvent for the reaction, the above-mentioned solvents can be used.

[0186] The reaction temperature is not particularly limited. From the viewpoint of allowing the reaction to proceed sufficiently, the reaction temperature may be, for example, 20 to 100°C, 30 to 80°C, or 40 to 70°C. The reaction time is, for example, 30 minutes to 24 hours, 1 to 12 hours, or 3 to 6 hours. The reaction product is sampled to measure the number average molecular weight, the concentration of remaining amino groups or isocyanate groups, and the like, and the reaction time can be adjusted so that the desired reaction product is obtained.

[0187] <Antenna Substrate Material Composition> In some embodiments, an antenna substrate material composition contains the antenna substrate material of any of the above-described embodiments and a solvent. Examples of the solvent contained in the composition include the above-described reaction solvents that can be used in synthesizing the block copolymer. The solvent preferably contains at least one solvent selected from the group consisting of N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone (NEP), γ-butyrolactone (GBL), and 3-methoxy-N,N-dimethylpropanamide (MPA), and more preferably contains at least one solvent selected from the group consisting of N-ethyl-2-pyrrolidone (NEP), γ-butyrolactone (GBL), and 3-methoxy-N,N-dimethylpropanamide (MPA).

[0188] The composition may further contain optional components such as polyamide, polyethersulfone, acrylic polymer, epoxy compound, isocyanate compound, melamine compound, filler, defoamer, preservative, surfactant, etc. The composition can be produced, for example, by mixing and stirring a block copolymer, a solvent, and optional components as needed. The composition may be, for example, a composition that does not contain a photoacid generator, a composition that does not contain a crosslinking agent, a composition that does not contain a photosensitizer, a composition that does not contain a photopolymerization initiator, etc. The composition may be a thermosetting composition or a photosensitive composition. The composition may be a non-photosensitive composition, from the viewpoints of excellent storage stability and the ability to form a polyimide material in the form of a film, layer, membrane, etc., by a simple method. According to some embodiments, the composition may be a composition that does not contain at least one selected from the group consisting of a photoacid generator, a crosslinking agent, a photosensitizer, and a photopolymerization initiator.

[0189] The content of the block copolymer can be within a range suitable for the intended use of the composition, for example, 5 to 50 mass %, 8 to 40 mass %, or 10 to 30 mass %, based on the mass of the composition.

[0190] <Polyimide Material> In some embodiments, a polyimide material can be obtained using the antenna substrate material of any of the above-described embodiments or the composition of any of the above-described embodiments. For example, since the block copolymer contains a polyamic acid block (BA), a polyimide can be obtained by converting the amic acid group into an imide group through ring closure (this conversion may be referred to as "imidization" in the present disclosure). The imidization method is not particularly limited. A method of heating the block copolymer is preferably used because it is simple. The heating temperature is, for example, 250 to 400°C. The polyimide material contains polyimide and may further contain an optional component. The optional component may be, for example, any of the above-described optional components that can be contained in the antenna substrate material or composition.

[0191] The polyimide obtained from the block copolymer contains a polyimide block (BI) and a polyimide block (BI-A) which is a block obtained by imidizing a polyamic acid block (BA). The polyimide block (BI) and the polyimide block (BI-A) are different blocks. Due to the block structure, the polyimide exhibits a low coefficient of thermal expansion. When the polyimide has a hydrocarbon group (X), it tends to exhibit a low dielectric constant and a low dielectric loss tangent. Furthermore, when the polyimide has a hydrocarbon group (X), it tends to exhibit a low water absorption rate.

[0192] The dielectric constant of the polyimide material is, for example, 3.50 or less, 3.00 or less, 2.95 or less, 2.90 or less, 2.85 or less, or 2.80 or less at a frequency of 10 to 100 GHz or a frequency of 10 to 300 GHz, from the viewpoint of obtaining excellent insulation properties over a wide frequency band. The dielectric constant of the polyimide material is not particularly limited, but is, for example, 2.0 or more. The dielectric constant (Dk) of the polyimide material can be measured using a polyimide film (e.g., 100 μm thick) formed using an antenna substrate material or composition by a balanced disk resonance method at a measurement temperature of 25°C. The dielectric constant (Dk) may be a value obtained by measuring the polyimide film immediately after thoroughly drying it and leaving it to stand for 24 hours in an atmosphere at a temperature of 23°C and a relative humidity of 50%. The relative dielectric constant of the polyimide material preferably satisfies the above range at a frequency of 10 GHz, more preferably at frequencies of 10 GHz and 100 GHz, even more preferably at frequencies of 10 GHz, 30 GHz, 50 GHz, and 100 GHz, and particularly preferably at frequencies of 10 GHz, 30 GHz, 50 GHz, 100 GHz, and 300 GHz.

[0193] The dielectric dissipation factor of the polyimide material is, for example, 0.0100 or less, 0.0070 or less, 0.0050 or less, 0.0040 or less, 0.0030 or less, or 0.0020 or less at a frequency of 10 to 100 GHz or a frequency of 10 to 300 GHz, from the viewpoint of suppressing transmission loss over a wide frequency band. The dielectric dissipation factor of the polyimide material is not particularly limited, but is, for example, 0.0005 or more. The dielectric dissipation factor (Df) can be measured using a polyimide film (e.g., 100 μm thick) by a balanced disk resonance method at a measurement temperature of 25°C. The dielectric dissipation factor (Df) may be a value obtained by measuring the polyimide film immediately after thoroughly drying it and leaving it to stand for 24 hours in an atmosphere at a temperature of 23°C and a relative humidity of 50%. The dielectric loss tangent of the polyimide material preferably satisfies the above range at a frequency of 10 GHz, more preferably at frequencies of 10 GHz and 100 GHz, even more preferably at frequencies of 10 GHz, 30 GHz, 50 GHz, and 100 GHz, and particularly preferably at frequencies of 10 GHz, 30 GHz, 50 GHz, 100 GHz, and 300 GHz.

[0194] The coefficient of thermal expansion (CTE) of the polyimide material is, for example, 80 ppm / K or less, 50 ppm / K or less, or 20 ppm / K or less from the viewpoint of obtaining excellent heat resistance. The coefficient of thermal expansion of the polyimide material is, for example, -5 ppm / K or more, 0 ppm / K or more, 10 ppm / K or more, or 15 ppm / K or more, taking into consideration that the polyimide film will be attached to another material when used. The coefficient of thermal expansion (ppm / K) can be determined by converting the average linear thermal expansion coefficient (ppm / °C) from 30 to 200°C measured using a polyimide film (e.g., 25 μm thick) at a heating rate of 10°C / min using a thermomechanical analyzer.

[0195] The glass transition temperature (Tg) of the polyimide material is, for example, 200°C or higher, 250°C or higher, or 300°C or higher from the viewpoint of heat resistance. The glass transition temperature (Tg) of the polyimide material is not particularly limited, but is, for example, 600°C or lower. The glass transition temperature can be determined as the temperature (°C) corresponding to the inflection point in a linear thermal expansion coefficient curve from 30 to 200°C measured using a polyimide film (for example, 25 μm thick) at a heating rate of 10°C / min using a thermomechanical analyzer.

[0196] More specifically, the relative permittivity, dielectric loss tangent, coefficient of thermal expansion, and glass transition temperature of a polyimide material can be measured by preparing a polyimide film according to the method described in the Examples and using the prepared polyimide film according to the method described in the Examples.

[0197] <Metal-Clad Laminate> In some embodiments, a metal-clad laminate is obtained using the antenna substrate material or composition of any of the above-described embodiments. The metal-clad laminate is used to obtain an antenna substrate. The metal-clad laminate may be a flexible substrate or a rigid substrate. The metal-clad laminate has a polyimide material layer and a metal layer in contact with the polyimide material layer. The antenna substrate may have a metal layer on only one side of the polyimide material layer, or on both sides of the polyimide material layer. The polyimide material layer may consist of a single polyimide material layer, or may include multiple polyimide material layers. When the insulating substrate includes multiple polyimide material layers, the insulating substrate may have an adhesive layer between the polyimide material layers.

[0198] The material of the metal layer may be, for example, copper, aluminum, gold, silver, or an alloy thereof. The metal layer is preferably copper foil. The polyimide layer has high adhesion even to copper foil with a small surface roughness, such as non-roughened copper foil or low-roughness copper foil. Copper foil with a small surface roughness can reduce transmission loss. The copper foil has a surface roughness (ten-point average roughness: Rz 0.01) according to JIS B 0601:2001, for example. ＪＩＳ) is 3.0 μm or less, 2.0 μm or less, or 1.0 μm or less. The lower limit of the surface roughness is not particularly limited, but is, for example, 0.5 μm or more. An example of a metal-clad laminate is a flexible copper clad laminate (FCCL).

[0199] <Antenna Substrate> In some embodiments, an antenna substrate is obtained using the antenna substrate material, composition, or metal-clad laminate of any of the above-described embodiments. The antenna substrate may be a printed circuit board. Examples of printed circuit boards include flexible boards and rigid boards. Examples of printed circuit boards include single-sided boards, double-sided boards, and multilayer boards. For example, organic materials contained in printed circuit boards, such as insulating substrate materials, protective films, and insulating layers, are obtained using the antenna substrate material or composition. Organic materials contained in printed circuit boards, such as insulating substrate materials, protective films, and insulating layers, may include the polyimide material of the above-described embodiments.

[0200] The antenna substrate can be used in various frequency bands because the dielectric properties of the polyimide material change little over a wide frequency band (e.g., from millimeter waves to terahertz waves). The antenna substrate can also be used as a substrate for antennas that operate in multiple frequency bands. The polyimide material exhibits good adhesion to the conductive layer, allowing for a wide design margin, easy handling, and efficient manufacturing of the antenna substrate. The polyimide material has a small coefficient of thermal expansion and excellent dimensional stability, allowing for antennas with good antenna gain to be obtained and suitable for use in multiple frequency bands.

[0201] In some embodiments, the antenna substrate includes an insulating substrate and a conductive layer in contact with the insulating substrate. The antenna substrate may have a conductive layer on only one side of the insulating substrate, or on both sides of the insulating substrate. The insulating substrate includes one polyimide material layer or multiple polyimide material layers. The insulating substrate may have an insulating layer other than the polyimide material layer. The insulating layer may be, for example, an insulating film, an insulating sheet, a prepreg, or the like. When the insulating substrate includes multiple layers selected from polyimide material layers and insulating layers other than polyimide material layers, the insulating substrate may have a conductive layer, an adhesive layer, or the like between each layer. The antenna substrate may further include an interlayer conductive portion. The conductive layer may have the shape of, for example, a power supply pattern, a ground pattern, a wiring pattern, or the like. The material of the conductive layer and the interlayer conductive portion may be, for example, copper, aluminum, gold, silver, an alloy thereof, or the like.

[0202] The antenna substrate may be, for example, a printed wiring board on which a transmission line (such as a microstrip line, a slot line, or a coplanar line), a power supply circuit, through holes, vias, and the like are formed.

[0203] In some embodiments, the antenna substrate is used to mount a plurality of antenna elements on a substrate. In some embodiments, the antenna substrate is used to mount an antenna device on a substrate.

[0204] FIG. 1 shows an example of an antenna substrate. The antenna substrate 110 is a composite printed circuit board including a printed wiring board 120 and a printed wiring board 130. The printed wiring board 120 is a multilayer printed wiring board including multiple polyimide material layers. The polyimide material layers 120a, 120b, 120c, 120d, 120e, and 120f may have the same or different compositions. The printed wiring board 120 may include an adhesive layer between the polyimide material layers. The printed wiring board 120 includes a conductive layer 121 and an interlayer conductive portion 122. An antenna element is mounted on the surface of the printed wiring board 120 facing the polyimide material layer 120a. The printed wiring board 120 includes a conductive layer (not shown) on the surface of the polyimide material layer 120a. The conductive layer may include a conductive layer having a wiring pattern shape and a conductive layer having a pattern shape for connecting to the antenna element. The printed wiring board 120 may also have a conductive layer on the surface of the polyimide material layer 120f.

[0205] The printed wiring board 130 is a multilayer printed circuit board having multiple insulating layers. The insulating layers 130a, 130b, 130c, 130d, 130e, and 130f may have the same or different compositions. The insulating layers may be polyimide material layers or insulating layers other than polyimide material layers. The printed wiring board 130 may have an adhesive layer between the insulating layers. The printed wiring board 130 has an interlayer conductive portion 132 and a conductive layer 131. A semiconductor element is mounted on the surface of the printed wiring board 130 facing the insulating layer 130f. The printed wiring board 130 has a conductive layer on the surface of the insulating layer 130f. The conductive layer may include a conductive layer (not shown) having a wiring pattern shape and a conductive layer 133 having a pattern shape for connecting to the semiconductor element. The printed wiring board 130 may also have a conductive layer on the surface of the insulating layer 130a.

[0206] In the printed wiring board 120, at least some of the multiple polyimide material layers may be insulating layers other than polyimide material layers. In this case, at least the layer closest to the mounting portion of the antenna element (polyimide material layer 120a) may be a polyimide material layer. While FIG. 1 shows an example of the printed wiring board 120 having multiple polyimide material layers, other examples of the printed wiring board 120 include printed wiring boards having one polyimide material layer. While FIG. 1 shows an example of a composite printed wiring board having two printed wiring boards as the antenna substrate 110, other examples of the antenna substrate include antenna substrates having one or three or more printed wiring boards.

[0207] 2 shows an example of an antenna substrate. The antenna substrate 210 has one printed wiring board. The antenna substrate 210 has an insulating layer 220, an insulating layer 230, conductive layers 221, 241, and 233, and a via 232. A power amplifier is mounted on the surface of the conductive layer 221, and an antenna element is mounted on the side of the antenna substrate 210.

[0208] <Antenna Device> The antenna device includes the antenna substrate of the above-described embodiment and an antenna element located on one side of the substrate. The antenna element may be a patch antenna (also called a "microstrip antenna"). The antenna device may be an array antenna device having antenna elements located in an array. The array antenna device may be a phased array antenna device and may be used in beamforming technology.

[0209] In some embodiments, the antenna device is an antenna module including the antenna substrate of the above-described embodiment, an antenna located on one side of the substrate, and a radio frequency integrated circuit (RF-IC) located on the other side of the substrate. The antenna device may further include components included in a typical antenna device. Examples of the components include a switch, a power amplifier, a low-noise amplifier, an attenuator, a phase shifter, a signal combiner-demultiplexer, a mixer, an amplifier circuit, etc.

[0210] The antenna module includes one or more antennas. For example, the antenna module may be a module including only one set of array antennas, or a multi-array antenna module including multiple sets of array antennas. The antenna module may be a multi-band antenna module used in multiple frequency bands. When the antenna operates in multiple frequency bands, it is desirable that the organic material has small changes in dielectric properties and excellent dimensional stability over a wide frequency band. For example, a multi-band antenna module including only one set of array antennas can achieve a compact module.

[0211] Examples of the shape of the antenna device include AiB (Antenna in Board), AiP (Antenna in Package), etc. In any shape, from the viewpoint of keeping transmission loss low, it is desirable that the polyimide material contained in the antenna substrate has a small dielectric constant, a small dielectric loss tangent, and a small coefficient of thermal expansion.

[0212] <Radio Unit, Radio Substation> The antenna device can be used in, for example, a radio unit (RU), a radio substation, a base station, a user terminal, a communication device, a communication system, etc. According to some embodiments, there are provided an RU, a radio substation, a smartphone, an advanced driver-assistance system (ADAS), etc., that include the antenna device of the above-described embodiments.

[0213] <Examples of Embodiments> Examples of embodiments of the present invention are listed below. The present invention is not limited to the following embodiments. [1] An antenna substrate material containing a block copolymer, the block copolymer containing a polyimide block (BI) and a polyamic acid block (BA). [2] The antenna substrate material according to [1] above, wherein the block copolymer contains a structural unit (X) having a group (X) containing at least one non-aromatic hydrocarbon group. [3] The antenna substrate material according to [1] or [2] above, wherein the block copolymer contains a structural unit (Y) having a group (Y) containing at least one aromatic ring group. [4] An antenna substrate material according to [1] above, wherein the block copolymer contains a polyimide block (BI) and a polyamic acid block (BA), and contains a structural unit represented by the above formula (I) and a structural unit represented by the above formula (A), and wherein at least the R Ａ and the above R Ｃ are different, or at least the above R Ｂ and the above R Ｄ [5] The antenna substrate material according to the above [4], wherein the block copolymer contains at least one selected from the group consisting of a structural unit represented by the above formula (XI) and a structural unit represented by the above formula (XA). [6] The antenna substrate material according to the above [4] or [5], wherein the block copolymer contains at least one selected from the group consisting of a structural unit represented by the above formula (YI) and a structural unit represented by the above formula (YA). [7] The antenna substrate material according to the above [4] or [5], wherein the block copolymer contains at least one selected from the group consisting of a structural unit represented by the above formula (XI) (where R １ and R ２ is the group (X), and the at least one non-aromatic hydrocarbon group has a total carbon number of 9 or more. ３ and R ４ wherein at least one of the group (X) is a group in which the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more. [8] The block copolymer contains at least one structural unit represented by the formula (YI) (where R５ and R ６ are each independently a group containing an aromatic hydrocarbon group, and a structural unit represented by the above formula (YA) (wherein R ７ and R ８ are each independently a group containing an aromatic hydrocarbon group.) [9] The antenna substrate material according to any one of the above [4] to [7], wherein the polyimide block (BI) contains a structural unit represented by the above formula (XI).

[10] The antenna substrate material according to any one of the above [4] to [9], wherein the polyamic acid block (BA) contains a structural unit represented by the above formula (YA).

[11] The block copolymer according to any one of the above [4] to [9], wherein the block copolymer contains a structural unit represented by the above formula (XI) (where R １ is the group (X).) and a structural unit represented by the above formula (YA) (wherein R ７

[12] The antenna substrate material according to any one of the above [4] to

[10] , wherein the block copolymer contains a structural unit represented by the above formula (YI) (where R ５ is a group containing an aromatic hydrocarbon group, and a structural unit represented by the above formula (XA) (wherein R ３is the group (X).

[13] The antenna substrate material according to any one of [4] to

[11] above, comprising a block copolymer, the block copolymer comprising a polyimide block (BI) and a polyamic acid block (BA), and having a structure derived from a diamine or diisocyanate and a structure derived from a tetracarboxylic dianhydride.

[14] The antenna substrate material according to

[13] above, wherein at least one of the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride comprises a structure having a group (X) containing at least one non-aromatic hydrocarbon group.

[15] The antenna substrate material according to

[13] or

[14] above, wherein the structure derived from a diamine or diisocyanate and the structure derived from a tetracarboxylic dianhydride comprise a structure having a group (Y) containing at least one aromatic ring group.

[16] The antenna substrate material according to any one of

[13] to

[15] above, wherein at least one of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride comprises a group (X) containing at least one non-aromatic hydrocarbon group, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more.

[17] The antenna substrate material according to any one of

[13] to

[16] above, wherein the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride comprise a group (Y) containing at least one aromatic ring group, wherein the aromatic ring group has a group that is an aromatic hydrocarbon group.

[18] The antenna substrate material according to any one of

[13] to

[17] above, wherein the structure derived from the diamine or diisocyanate contained in the polyimide block (BI) comprises a structure derived from a diamine or diisocyanate having a group (X) containing at least one non-aromatic hydrocarbon group.

[19] The antenna substrate material according to any one of

[13] to

[18] , wherein the structure derived from a diamine or diisocyanate contained in the polyamic acid block (BA) includes a structure derived from a diamine or diisocyanate having a group (Y) containing at least one aromatic ring group.

[20] The antenna substrate material according to any one of

[13] to

[19] , wherein the diamine- or diisocyanate-derived structure comprises: a group (X) containing at least one non-aromatic hydrocarbon group, the group being derived from a diamine or diisocyanate and having a group in which the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more; and a group (Y) containing at least one aromatic ring group, the group being derived from a diamine or diisocyanate and having a group in which the aromatic ring group is an aromatic hydrocarbon group.

[21] The antenna substrate material according to any one of

[13] to

[20] , wherein the block copolymer comprises a structure derived from dimer diamine or dimer diisocyanate.

[22] The antenna substrate material according to any one of [1] to

[21] , wherein the at least one non-aromatic hydrocarbon group is a saturated aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, an unsaturated alicyclic hydrocarbon group, or a group consisting of two or more types selected from these.

[23] The antenna substrate material according to any one of [1] to

[22] , wherein the group (X) is a saturated aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, an unsaturated alicyclic hydrocarbon group, or a group consisting of two or more selected from saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, and unsaturated alicyclic hydrocarbon groups.

[24] The antenna substrate material according to any one of [1] to

[23] , wherein the total number of carbon atoms of the saturated aliphatic hydrocarbon group and the unsaturated aliphatic hydrocarbon group contained in the group (X) is greater than the total number of carbon atoms of the saturated alicyclic hydrocarbon group and the unsaturated alicyclic hydrocarbon group contained in the group (X).

[25] The antenna substrate material according to any one of [1] to

[24] , wherein the group (X) contains a saturated alicyclic hydrocarbon group.

[26] The antenna substrate material according to any one of [1] to

[25] , wherein the group (X) does not contain an aromatic ring group.

[27] The antenna substrate material according to any one of [1] to

[26] above, wherein the group (X) contains a linear saturated aliphatic hydrocarbon group having 6 or more carbon atoms.

[28] The antenna substrate material according to any one of [1] to

[27] above, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 16 or more.

[29] The antenna substrate material according to any one of [1] to

[28] above, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 28 or more.

[30] The antenna substrate material according to any one of [1] to

[29] above, which is for a multiband antenna.

[31] The antenna substrate material according to any one of [1] to

[30] above, which is for a patch antenna.

[32] The antenna substrate material according to any one of [1] to

[31] above, wherein, when a film is produced using the antenna substrate material and the relative dielectric constant, dielectric loss tangent, and thermal expansion coefficient of the film at a frequency of 10 GHz are measured, the relative dielectric constant is 3.5 or less, the dielectric loss tangent is 0.0100 or less, and the thermal expansion coefficient is 80 ppm / K or less.

[33] The antenna substrate material according to any one of [1] to

[32] , wherein when a film is produced using the antenna substrate material and the relative dielectric constant and dielectric dissipation factor of the film are measured at frequencies of 10 GHz and 100 GHz, the relative dielectric constant is 3.5 or less and the dielectric dissipation factor is 0.0100 or less in both cases.

[34] A method for producing the antenna substrate material according to any one of [1] to

[33] , comprising: obtaining a polyimide (PI) using a diamine or diisocyanate and a tetracarboxylic dianhydride; obtaining a polyamic acid (PA) using a diamine and a tetracarboxylic dianhydride; and obtaining a block copolymer using the polyimide (PI) and the polyamic acid (PA).

[35] An antenna substrate material composition comprising the antenna substrate material according to any one of [1] to

[33] , and a solvent.

[0214] The disclosure of this application is related to the subject matter described in PCT / JP2024 / 003168, filed on January 31, 2024, the entire disclosure of which is incorporated herein by reference.

[0215] The embodiments of the present invention will be described in more detail with reference to examples, but the embodiments of the present invention are not limited to the following examples.

[0216] <Synthesis of Polyimide (PI) and Polyamic Acid (PA)> [Polyimide (PI-1)] 35.5 g (0.066 mol) of dimer diamine ("PRIAMINE 1075", Croda Japan Co., Ltd., containing a dimer diamine represented by the following formula) (hereinafter referred to as "DDA") was dissolved in 205.6 g of N-methylpyrrolidone and 30.8 g of xylene to obtain a diamine solution. 28.5 g (0.088 mol) of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (hereinafter referred to as "BTDA") was added to the diamine solution, and the reaction was carried out until a uniform, transparent solution was obtained. The reaction was carried out by stirring the solution at 50°C or less for one hour or more. The transparent solution was then subjected to a dehydrothermal imidization reaction while stirring at 180°C for four hours or more, to obtain a solution (varnish) of polyimide (PI-1) having an acid anhydride structure derived from BTDA at its terminal. The number average molecular weight of the polyimide (PI-1) was 3,000.

[0217]

[0218] [Polyimides (PI-2) to (PI-6)] Solutions of polyimides (PI-2) to (PI-6) were obtained in the same manner as for polyimide (PI-1), except that the diamines and tetracarboxylic dianhydrides shown in Table 2 were used.

[0219] [Polyamic Acid (PA-1)] 57.3 g (0.155 mol) of 4,4'-bis(4-aminophenoxy)biphenyl (hereinafter referred to as "BODA") was dissolved in 235.6 g of N,N'-dimethylacetamide and 167.9 g of N-methylpyrrolidone to obtain a diamine solution. 38.7 g (0.132 mol) of 3,3',4,4'-biphenyltetracarboxylic dianhydride (hereinafter referred to as "BPDA") was added to the diamine solution and reacted to obtain a solution of polyamic acid (polyimide precursor) (PA-1) having BODA-derived amine structures at the terminals. The reaction was carried out by stirring the solution at 50°C or below for at least 8 hours. The number average molecular weight of the polyamic acid (PA-1) was 4,000.

[0220] [Polyamic Acids (PA-2) to (PA-6)] Solutions of polyamic acids (PA-2) to (PA-6) were obtained in the same manner as for polyamic acid (PA-1), except that the diamines and tetracarboxylic dianhydrides shown in Table 2 were used instead.

[0221] Synthesis of Block Copolymer (Block Polyamic Acid Imide) Example 1 300.4 g of a solution of polyimide (PI-1) and 499.6 g of a solution of polyamic acid (PA-1) were mixed and reacted to obtain a varnish of block polyamic acid imide 1. The reaction was carried out by stirring the solution at 100°C or less for 1 hour or more. The number average molecular weight of block polyamic acid imide 1 was 30,000. The concentration of block polyamic acid imide 1 was 20% by mass based on the mass of the varnish. The block copolymer (block polyamic acid imide) is a material for an antenna substrate, and the varnish is a composition containing the block copolymer and a solvent.

[0222] Examples 2 to 9 Varnishes of block polyamic acid imides 2 to 9 were obtained in the same manner as in Example 1, except that the polyimide and polyamic acid solutions shown in Table 2 were used.

[0223] <Synthesis of Polyamic Acid> [Comparative Example 1] 76.6 g (0.38 mol) of 4,4'-diaminodiphenyl ether (hereinafter referred to as "ODA") was dissolved in 640.0 g of N,N'-dimethylacetamide to obtain a diamine solution. 81.8 g (0.38 mol) of pyromellitic dianhydride (hereinafter referred to as "PMDA") was added to the diamine solution and reacted to obtain a varnish of polyamic acid 1 (polyimide precursor). The reaction was carried out by stirring the solution at 50°C or less for 8 hours or more.

[0224] Comparative Example 2 A varnish of polyamic acid 2 was obtained in the same manner as in Comparative Example 1, except that the diamine and tetracarboxylic dianhydride shown in Table 3 were used instead.

[0225] Tables 2 and 3 show the diamines and tetracarboxylic dianhydrides used in the synthesis of the polyimides and polyamic acids, and the types and amounts of the polyimides and polyamic acids used in the synthesis of the block polyamic acid imides. Tables 2 and 3 also show the number average molecular weights of the polyimides and polyamic acids. The number average molecular weights were measured according to the following method.

[0226] The meanings of the abbreviations in Tables 2 and 3 are as follows: BTDA: 3,3',4,4'-benzophenonetetracarboxylic dianhydride BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride PMDA: pyromellitic dianhydride TAHQ: bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid) 1,4-phenylene DDA: dimer diamine BODA: 4,4'-bis(4-aminophenoxy)biphenyl PPD: p-phenylenediamine ODA: 4,4'-diaminodiphenyl ether m-TB: m-tolidine (4,4'-diamino-2,2'-dimethylbiphenyl)

[0227]

[0228]

[0229] (Number Average Molecular Weight) The number average molecular weight (Mn) was measured by gel permeation chromatography (GPC) and converted using a calibration curve of standard polystyrene. The calibration curve was approximated by a cubic equation using a set of five standard polystyrene samples ("TSK Standard POLYSTYRENE", manufactured by Tosoh Corporation). The GPC conditions are as follows: GPC apparatus: High-speed GPC apparatus HLC-8320GPC (manufactured by Tosoh Corporation) Detector: Ultraviolet absorption detector UV-8320 (manufactured by Tosoh Corporation) Column: Gelpack GL-S300MDT-5 (total of 2 columns) (manufactured by Resonac Corporation) Eluent: THF / DMF = 1 / 1 (volume ratio) + LiBr (0.06 mol / L) + H ３ P.O. ４ (0.06 mol / L) Flow rate: 1 mL / min Column size: 8 mm ID x 300 mm Sample concentration: 5 mg / 1 mL Injection volume: 5 μL Measurement temperature: 40°C

[0230] <Film Preparation> [Example 1] A film was prepared using the obtained varnish (composition) according to the following method. The surface of a commercially available glass substrate was degreased with acetone, and a varnish of block polyamic acid imide 1 was applied using a film applicator with a film thickness adjustment function so that the film would have a thickness of 100 μm after imidization. The applied varnish was pre-dried using a hot plate at 80°C for 30 minutes to form a layer of block polyamic acid imide 1. Next, the layer of block polyamic acid imide 1 was heated in an inert gas oven in a nitrogen atmosphere at 350°C for 30 minutes to obtain a film of block polyimide 1. The glass substrate on which the film was formed was immersed in warm water for approximately 15 minutes, and then the film was peeled off from the glass substrate to prepare a film with a thickness of 100 μm. A film with a thickness of 25 μm was prepared in the same manner as above, except that the varnish of block polyamic acid imide 1 was applied so that the film would have a thickness of 25 μm after imidization.

[0231] [Examples 2 to 9 and Comparative Examples 1 and 2] Films were obtained in the same manner as above, except that the varnish of block polyamic acid imide 1 was changed to the varnishes of Examples 2 to 9 and Comparative Examples 1 and 2.

[0232] <Film Evaluation> According to the following methods, the properties of the films prepared using the varnishes of Examples 1 to 9 and Comparative Examples 1 and 2 were evaluated. Tables 2 and 3 show the evaluation results.

[0233] (Relative permittivity and dielectric loss tangent) A film (film thickness 100 μm) was cut into a size of 48 mm in diameter, dried at 125°C for 1 hour, and then left to stand for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%. Thereafter, the dielectric properties (relative permittivity Dk and dielectric loss tangent Df) of the film were measured using a balanced disk resonator (BCDR). For the measurement, a "PS-XSN-100" manufactured by Keysight Technologies was used. The conditions were a frequency of 10 to 100 GHz and a measurement temperature of 25°C.

[0234] (Linear thermal expansion coefficient (thermal expansion coefficient) and glass transition temperature) A film (film thickness 25 μm) was cut into a width of 4 mm and a length of 25 mm to prepare a test piece. For the measurement, a thermomechanical analyzer ("TMA7100" manufactured by Hitachi High-Tech Science Corporation) was used. The test piece was heated from room temperature to 350 ° C. at a rate of 10 ° C. / min using a tensile method with a chuck distance of 10 mm and a load of 10 g, and then cooled to 30 ° C. at a rate of 10 ° C. / min. The temperature was again raised at a rate of 10 ° C. / min, and the average linear thermal expansion coefficient (ppm / ° C.) from 30 ° C. to 200 ° C. was calculated, and the obtained value was taken as the linear thermal expansion coefficient (ppm / K). The temperature corresponding to the inflection point of the linear thermal expansion coefficient curve was taken as the glass transition temperature (° C.).

[0235] <Preparation of Flexible Copper Clad Laminate (FCCL)> [Example 1] A flexible copper clad laminate (FCCL) was prepared using the obtained varnish (composition) according to the following method. Surface roughness (Rz ＪＩＳ A varnish of block polyamic acid imide 1 was applied to the matte surface of a low-roughening copper foil having a thickness of 1.2 μm using a film applicator with a film thickness adjustment function so that the film thickness after imidization would be 25 μm. The applied varnish was pre-dried using a hot plate at 80° C. for 30 minutes to form a layer of block polyamic acid imide 1. Next, the copper foil on which the layer of block polyamic acid imide 1 was formed was heated in an inert gas oven in a nitrogen atmosphere at 350° C. for 30 minutes to obtain an FCCL having a layer of block polyimide 1.

[0236] [Examples 2 to 9 and Comparative Examples 1 and 2] FCCL was obtained in the same manner as above, except that the varnish of block polyamic acid imide 1 was changed to the varnishes of Examples 2 to 9 and Comparative Examples 1 and 2.

[0237] <Evaluation of FCCL> According to the following method, the adhesion of the block polyimide was evaluated using the FCCL prepared using the varnishes of Examples 1 to 9 and Comparative Examples 1 and 2. Tables 2 and 3 show the evaluation results.

[0238] (90° Peel Strength) The copper foil of FCCL was etched into a 5 mm wide straight line. The peel strength was measured when the copper foil processed into the straight line was peeled off in a 90° direction relative to the surface direction of the block polyimide layer using a materials testing machine (Shimadzu Corporation's "Small Tabletop Tester EZ-S50N"). The pulling speed was 50 mm / min.

[0239] REFERENCE SIGNS LIST 110 Antenna substrate, 120 Printed wiring board, 120a to 120f Polyimide material layer, 121 Conductive layer, 122 Interlayer conductive portion, 130 Printed wiring board, 130a to 130f Insulating layer, 131 Conductive layer, 132 Interlayer conductive portion, 133 Conductive layer, 140 Connection portion, 141 Insulating layer, 142 Conductive portion, 210 Antenna substrate, 220 Insulating layer, 221 Conductive layer, 222 Conductive portion, 230 Insulating layer, 232 Conductive portion, 233 Conductive layer, 241 Conductive layer

Claims

1. A substrate material for an antenna, comprising a block copolymer, the block copolymer comprising a polyimide block (BI) and a polyamic acid block (BA).

2. The substrate material for an antenna according to claim 1, wherein the block copolymer comprises a structural unit (X) having a group (X) containing at least one non-aromatic hydrocarbon group.

3. The antenna substrate material according to claim 2, wherein the block copolymer comprises a structural unit (Y) having a group (Y) containing at least one aromatic ring group.

4. A block copolymer is contained, the block copolymer containing a polyimide block (BI) and a polyamic acid block (BA), and containing a structural unit represented by the following formula (I) and a structural unit represented by the following formula (A), and the block copolymer is at least Ａ and the following R Ｃ are different, or at least the following R Ｂ and the following R Ｄ A substrate material for antennas that is different from the above. (In the formula, R Ａ and R Ｂ each independently represents an organic group. (In the formula, R Ｃ and R Ｄ each independently represents an organic group.

5. The antenna substrate material according to claim 4, wherein the block copolymer contains at least one selected from the group consisting of a structural unit represented by the following formula (XI) and a structural unit represented by the following formula (XA): (In the formula, R １ and R ２ each independently represents an organic group; R １ and R ２ At least one of the groups (X) contains at least one non-aromatic hydrocarbon group. (In the formula, R ３ and R ４ each independently represents an organic group; R ３ and R ４ At least one of the groups (X) contains at least one non-aromatic hydrocarbon group.

6. The antenna substrate material according to claim 5, wherein the block copolymer comprises at least one selected from the group consisting of a structural unit represented by the following formula (YI) and a structural unit represented by the following formula (YA): (In the formula, R ５ and R ６ each independently represents a group (Y) containing at least one aromatic ring group. (In the formula, R ７ and R ８ each independently represents a group (Y) containing at least one aromatic ring group.

7. The block copolymer has a structural unit represented by formula (XI) (where R １ and R ２ is the group (X), and the at least one non-aromatic hydrocarbon group has a total carbon number of 9 or more. ３ and R ４ wherein at least one of the non-aromatic hydrocarbon groups is the group (X), and the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more.

8. The block copolymer contains a structural unit represented by the formula (YI) (wherein R ５ and R ６ are each independently a group containing an aromatic hydrocarbon group, and a structural unit represented by the formula (YA) (wherein R ７ and R ８ and each independently represents a group containing an aromatic hydrocarbon group.

9. The antenna substrate material according to any one of claims 5 to 8, wherein the polyimide block (BI) contains a structural unit represented by formula (XI).

10. The antenna substrate material according to claim 6 or 8, wherein the polyamic acid block (BA) contains a structural unit represented by the formula (YA).

11. The block copolymer has a structural unit represented by formula (XI) (where R １ is the group (X).) and a structural unit represented by the formula (YA) (wherein R ７ is a group containing an aromatic hydrocarbon group.

12. The block copolymer contains a structural unit represented by the formula (YI) (wherein R ５ is a group containing an aromatic hydrocarbon group, and a structural unit represented by the formula (XA) (wherein R ３ is the group (X).

13. A substrate material for an antenna, comprising a block copolymer, the block copolymer including a polyimide block (BI) and a polyamic acid block (BA), and having a structure derived from a diamine or diisocyanate and a structure derived from a tetracarboxylic dianhydride.

14. The antenna substrate material according to claim 13, wherein at least one of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride includes a structure having a group (X) containing at least one non-aromatic hydrocarbon group.

15. The antenna substrate material according to claim 14, wherein the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride include a structure having a group (Y) containing at least one aromatic ring group.

16. The antenna substrate material according to any one of claims 13 to 15, wherein at least one of the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride comprises a group (X) containing at least one non-aromatic hydrocarbon group, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 9 or more.

17. The antenna substrate material according to claim 16, wherein the structure derived from the diamine or diisocyanate and the structure derived from the tetracarboxylic dianhydride include a structure having a group (Y) containing at least one aromatic ring group, wherein the aromatic ring group is an aromatic hydrocarbon group.

18. The antenna substrate material according to any one of claims 13 to 17, wherein the structure derived from a diamine or diisocyanate contained in the polyimide block (BI) includes a structure derived from a diamine or diisocyanate having a group (X) containing at least one non-aromatic hydrocarbon group.

19. The antenna substrate material according to claim 18, wherein the structure derived from a diamine or diisocyanate contained in the polyamic acid block (BA) includes a structure derived from a diamine or diisocyanate having a group (Y) containing at least one aromatic ring group.

20. The antenna substrate material according to any one of claims 13 to 19, wherein the structure derived from a diamine or diisocyanate comprises: a group (X) containing at least one non-aromatic hydrocarbon group, the at least one non-aromatic hydrocarbon group having a total carbon number of 9 or more; and a group (Y) containing at least one aromatic ring group, the aromatic ring group being an aromatic hydrocarbon group.

21. The antenna substrate material according to any one of claims 13 to 20, wherein the block copolymer contains a structure derived from dimer diamine or dimer diisocyanate.

22. The antenna substrate material according to any one of claims 2, 3, 5 to 12, and 14 to 20, wherein the at least one non-aromatic hydrocarbon group is a saturated aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, an unsaturated alicyclic hydrocarbon group, or a group consisting of two or more groups selected from these.

23. The antenna substrate material according to any one of claims 2, 3, 5 to 12, and 14 to 20, wherein the group (X) is a saturated aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, a saturated alicyclic hydrocarbon group, an unsaturated alicyclic hydrocarbon group, or a group consisting of two or more groups selected from saturated aliphatic hydrocarbon groups, unsaturated aliphatic hydrocarbon groups, saturated alicyclic hydrocarbon groups, and unsaturated alicyclic hydrocarbon groups.

24. The antenna substrate material according to any one of claims 2, 3, 5 to 12, and 14 to 20, wherein the total number of carbon atoms in the saturated aliphatic hydrocarbon group and the unsaturated aliphatic hydrocarbon group contained in said group (X) is greater than the total number of carbon atoms in the saturated alicyclic hydrocarbon group and the unsaturated alicyclic hydrocarbon group contained in said group (X).

25. The antenna substrate material according to any one of claims 2, 3, 5 to 12, 14 to 20, and 22 to 24, wherein the group (X) includes a saturated alicyclic hydrocarbon group.

26. The antenna substrate material according to any one of claims 2, 3, 5 to 12, 14 to 20, and 22 to 25, wherein the group (X) does not contain an aromatic ring group.

27. The antenna substrate material according to any one of claims 2, 3, 5 to 12, 14 to 20, and 22 to 26, wherein the group (X) contains a linear saturated aliphatic hydrocarbon group having 6 or more carbon atoms.

28. The antenna substrate material according to any one of claims 2, 3, 5 to 12, 14 to 20, and 22 to 26, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 16 or more.

29. The antenna substrate material according to any one of claims 2, 3, 5 to 12, 14 to 20, and 22 to 26, wherein the total number of carbon atoms in the at least one non-aromatic hydrocarbon group is 28 or more.

30. The antenna substrate material according to any one of claims 1 to 29, which is for a multi-band antenna.

31. The antenna substrate material according to any one of claims 1 to 30, which is used for a patch antenna.

32. The antenna substrate material according to any one of claims 1 to 31, wherein when a film is produced using the antenna substrate material and the relative dielectric constant, dielectric dissipation factor, and thermal expansion coefficient of the film are measured at a frequency of 10 GHz, the relative dielectric constant is 3.5 or less, the dielectric dissipation factor is 0.0100 or less, and the thermal expansion coefficient is 80 ppm / K or less.

33. The antenna substrate material according to any one of claims 1 to 32, wherein when a film is produced using said antenna substrate material and the relative dielectric constant and dielectric dissipation factor of said film are measured at frequencies of 10 GHz and 100 GHz, the relative dielectric constant is 3.5 or less and the dielectric dissipation factor is 0.0100 or less in both cases.

34. A method for producing an antenna substrate material according to any one of claims 1 to 33, comprising: obtaining a polyimide (PI) using a diamine or diisocyanate and a tetracarboxylic dianhydride; obtaining a polyamic acid (PA) using a diamine and a tetracarboxylic dianhydride; and obtaining a block copolymer using the polyimide (PI) and the polyamic acid (PA).

35. An antenna substrate material composition comprising the antenna substrate material according to any one of claims 1 to 33 and a solvent.

Images