JPH0426607B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to an addition-type imide resin composition used for manufacturing printed wiring boards or molded products. [Background technology] Addition-type imides have recently been used as manufacturing materials for printed wiring boards or molded products because they have a high degree of heat resistance, good workability, and excellent cost performance. Resins have come to be widely used in various fields. However, in the cutting-edge field of office automation equipment such as computers, copiers, and printers, the current situation is that conventional addition-type imide resins do not necessarily satisfy the requirements. This is thought to be due to the fact that the coefficient of thermal expansion of conventional addition-type imide resins is very small compared to other resins, but larger than the requirements in the cutting-edge field as described above. For example, multilayer printed wiring boards used in computers and the like have recently become more densely packaged and multilayered, and the following requirements have been made. In order to enable high-density mounting of leadless components etc. on the surface of the wiring board, the wiring board
It should have a low coefficient of thermal expansion in the direction. When increasing the number of layers, the board thickness increases and the through-hole diameter tends to become smaller (increasing the aspect ratio). It has a low coefficient of thermal expansion in the z direction (thickness direction). In addition, molded products used in office automation equipment such as copiers and printers need to operate at higher speeds and in higher temperature environments in order to make the equipment smaller and more sophisticated. Molded products are required to have a high degree of dimensional stability, that is, a low coefficient of thermal expansion. However, as mentioned above, conventional addition-type imide resins have not been able to achieve a low coefficient of thermal expansion in the various fields mentioned above. For example, polymaleimide resins, those made by reacting bismaleimide with diamines, triazines, aminophenols, and phenols, etc., those made by reacting nadzic anhydride with terminal amines, etc., which have been put into practical use to date, or When the inventors investigated imide oligomers having -C≡C at the end, all of them were 50 to 70 × 10 ^-6 ×K ^-1
It had a much larger coefficient of thermal expansion than the requirements in each of the above-mentioned fields. Therefore, it is desired to develop an addition type imide resin having a low coefficient of thermal expansion that satisfies the above requirements. [Object of the Invention] The present invention was made in view of the above circumstances, and it is an object of the present invention to provide an addition-type imide resin composition that can realize the low coefficient of thermal expansion required in cutting-edge fields. [Disclosure of the Invention] In order to achieve the above object, the inventors first studied the relationship between the structure of the resin and the coefficient of thermal expansion. As a result, in addition-type imide resins made by reacting unsaturated bisimide and diamine, the bonding positions and bonding distances of the unsaturated imide rings and amino groups, which are the functional groups of the raw materials, in other words, the structure between the functional groups are defined. It was discovered that the coefficient of thermal expansion could be made extremely low by doing so, and this invention was completed. That is, this invention relates to an unsaturated bisimide in which two moieties containing at least an unsaturated imide ring are bonded to one benzene nucleus in a meta-position to each other, and the following general formulas () and (). [However, if the hydrogen of the naphthalene nucleus in the structural unit represented by the above formula is substituted with at least one selected from the group consisting of an inert alkyl group, a perfluoroalkyl group, a halogen, and a functional group that does not participate in the resin formation reaction. may have been done. ] The gist is an addition-type imide resin composition in which at least one of the diamines represented by the following is blended as a resin component. This invention will be explained in detail below. The unsaturated bisimide used in this invention is represented by the following formula (A), and the diamine is represented by the following formulas () and (). [In the formula, D represents a divalent organic group having a carbon-carbon double bond, and m and n represent the same or different integers of 0 or more. That is,
This also includes cases where R ₁ and R ₂ are absent. [However, if the hydrogen of the naphthalene nucleus in the structural unit represented by the above formula is substituted with at least one selected from the group consisting of an inert alkyl group, a perfluoroalkyl group, a halogen, and a functional group that does not participate in the resin formation reaction. may have been done. ] In this invention, at least one of the compounds of the above formula () and formula () is used as the diamine component. The symbols R ₁ and R ₂ can be the same or different and represent the divalent groups shown below. −CH ₂ −,

[Formula] −SO ₂ −, −NH−,

[Formula] -CS- Also, in the above formula (A), at least one of the four hydrogen atoms bonded to the benzene nucleus is capable of forming a resin by an inert alkyl group, a perfluoroalkyl group, a halogen, etc. It may be substituted with a group that is not directly involved. The group D has the formula: derived from ethylene acid anhydrides, such as maleic anhydride, citraconic anhydride,
Products of the Diels-Alder reaction between tetrahydrophthalic anhydride, itaconic anhydride, and cyclodiene and one of these anhydrides, and hydrogen atoms of these purified products are substituted with alkyl groups, halogens, etc. Examples include derivatives represented by the following formulas, and groups represented by the following formulas. Preferred examples of the unsaturated bisimide represented by formula (A) include metaphenylene diamine, 2,4-diaminotoluene, 4,6-dimethylmetaphenylene diamine, 2,4-diaminomethylene, and 4-chlorometaphenylene. Diamine, 5-nitrometaphenylenediamine, 3,5-diaminobenzoic acid, metaaminobenzylamino, metaxylylenediamine, 2,6-dimethylmetaphenylenediamine,
Examples include those obtained by reacting diamines such as meta-aminobenzoic acid hydrazide and isophthalic acid dihydrazide, or diisocyanates derived therefrom with the compound represented by the above formula (). Preferred examples of diamines represented by formula () include the following. 1,3-naphthylene diamine, 1,4-naphthylene diamine, and derivatives thereof. Preferred examples of diamines represented by formula () include the following. 1,5-naphthylene diamine, 1,6-naphthylene diamine, 1,7-naphthylene diamine,
2,6-naphthylene diamine, 2,7-naphthylene diamine, and derivatives thereof. These unsaturated bisimides and diamines can be used alone or in combination of two or more. The addition type imide resin composition according to this invention is
It is obtained by blending the above unsaturated bisimide and diamine as resin components. The blending ratio of both is usually a molar ratio of unsaturated bisimide/unsaturated bisimide/
Diamine is preferably within the range of 0.5/1.0 to 10.0/1.0, more preferably within the range of 1.7/1.0 to 3.5/1.0, but may be outside this range depending on the application. . Further, in the addition-type imide resin composition according to the present invention, the unsaturated bisimide and diamine may be simply blended as resin components, but a portion of the unsaturated bisimide and diamine may be blended as resin components.
The so-called, which was preliminarily reacted at a temperature below ℃
It may also be supplied in prepolymer form. In that case, even if it is supplied in a solid form such as a powder, it may also be a so-called prepolymer obtained in the presence of a polar solvent such as N-methylpyrrolidone or N,N-dimethylacetamide. It does not matter if it is now supplied as a varnish. It goes without saying that the addition-type imide resin composition of the present invention also includes a state in which the unsaturated bisimide and diamine are completely reacted. In the addition-type imide resin composition according to the present invention as described above, the bending of the polymer main chain caused by the addition reaction of the amino group to the unsaturated bisimide ring occurs during resin formation. It is absorbed by the bonding structure of the benzene nucleus and naphthalene nucleus inside. In addition, in the unsaturated bisimide or diamine, most of the space between the functional groups at both ends is occupied by the benzene nucleus or naphthalene nucleus, so that the space between the functional groups at both ends does not shrink any more, so-called.
It stretches like a chain. Therefore, in the addition-type imide resin composition according to the present invention, the polymer main chain formed by resinization is extremely difficult to deform, and the coefficient of thermal expansion can be made extremely low. As described above, since the addition-type imide resin composition of the present invention has an extremely low coefficient of thermal expansion, it is suitable for molded products in fields related to multilayer printed wiring boards and OA equipment such as large computers as described above. Other possible applications include, for example, the following. Coil insulation materials, spacer materials for heavy electric motors,
Commutator insulation materials, mechanical parts for robots, other connectors for IC testing, automobile parts, paints, etc. In addition, in the field of printed wiring boards, insulating base materials for printed circuits formed on metal plates, cured powders are used as fillers for other resins, and Kevlar cloth, quartz cloth, etc. New applications such as composites with low thermal expansion fiber materials can be considered. In particular, in composites with the above-mentioned Kevlar cloth, quartz cloth, etc., by using the addition type imide resin composition according to the present invention, it is possible to reduce stress at the fiber-resin interface, and as a result, It is possible to prevent the occurrence of fine cracks at the interface, and it is possible to realize a composite with the above-mentioned low thermal expansion fiber material, which has not been possible with conventional resin compositions. As described above, the addition type imide resin composition according to the present invention can be applied to a wide range of fields. Next, examples of the present invention will be described together with comparative examples. Examples 1 to 6, Comparative Examples 1 to 3 After mixing unsaturated bisimide powder and diamine powder in the formulation shown in Table 1, about 5 g of this mixture was taken out and heated at 180 to 200°C. The mixture was placed in a mold (a three-cavity mold for obtaining a molded product with a diameter of 5 mm and a thickness of 30 mm) maintained at a temperature of 5 mm, and melted. Thereafter, after confirming that the viscosity increased due to the addition reaction, a pressure of 50 kg/cm ² was applied to the mold, and heating and pressurization was performed for 10 minutes. After 10 minutes, continue to apply pressure to 100~
The molded product was cooled to 150°C, then the pressure was stopped and the molded product was taken out. This product is placed in a nitrogen atmosphere to release the internal strain accumulated during molding.
After-cure was performed at 250°C for 2 hours. The obtained molded product was cut into a length of 20.00 mm, and this was
Using a thermal expansion coefficient measuring device manufactured by Rigaku Denki Co., Ltd., the compressive load was 2 g, the heating rate was 5°C/min, and the temperature range was from room temperature to
Measurement was performed under the condition of 350℃, and the coefficient of thermal expansion (40 to 250℃
average value) and glass transition temperature were measured. The results are shown in the lower column of Table 1. In addition, when measuring the coefficient of thermal expansion,
Measurements were carried out paying attention to the following points. This is because, if attention is not paid to the following points, there is a risk that the coefficient of thermal expansion will be measured to be smaller than it actually is. In other words, each compounded component was prevented from being mixed with moisture or foreign matter. In addition, during molding, conditions were selected to prevent the generation of voids, and after molding, sufficient after-cure was performed to remove residual strain. In addition, care was taken to prevent the molded product from being oxidized during this after-cure.

[Table] Examples 7 to 10, Comparative Examples 4 and 5 The unsaturated bisimide and diamine shown in Table 2 were weighed into a 2000 ml four-necked flask together with the polar solvent shown in the same table. Thereafter, a stirring rod, a thermometer, and a condenser were attached to the four-necked flask, and nitrogen gas was passed through the side port. After replacing the air in the flask with nitrogen, heating was performed using an oil bath. Stirring was started as the contents dissolved, and stirring was continued for the time shown in Table 2 while maintaining the temperature shown in Table 2. After that, the reactant was quickly cooled to room temperature. A prepolymer solution was obtained. The obtained prepolymer solution was transferred to a stainless steel vat, and a glass cloth (manufactured by Nittobo Co., Ltd.) was placed there.
WE-113) to impregnate it, then 150
Dry for 10 minutes at 49°C to remove resin content.
~50% prepreg was obtained. This thing is 200mm×
Cut 200mm pieces, stack 4 sheets, and coat both sides with copper foil (circuit oil made by Furukawa Electric Co., Ltd.).
TSTO, 1/2 oz) was placed to form a laminate. Thereafter, this was maintained at an actual pressure of 40 Kg/m ² and a temperature of 200°C. After 60 minutes, the laminate was cooled to room temperature while applying pressure, and then heated in nitrogen at 250℃ for 2 hours.
After curing for several hours, a double-sided copper foil-clad laminate was obtained. The characteristic values of the obtained laminate are shown in the lower column of Table 2. In addition, in the table, samples for measuring the coefficient of thermal expansion were created as follows. First, the copper foil on both sides of the laminate obtained in the above process was removed by etching. Next, this product was sufficiently washed with water and then dried at 70°C for 5 hours to obtain a laminate with a resin content of 42.5 to 43%. This is x x y = 20 x 5 (mm), x x y = 5 x 20 (mm),
Cut into pieces x x y = 5 x 5 (mm), heat at 200℃ for 20 minutes in a nitrogen atmosphere to completely remove residual strain, and then use them for measurement without absorbing moisture in the air. did. Note that the reason why the resin content is kept within a narrow range of 42.5 to 43% is that in such laminate samples, the measured values vary significantly depending on the difference in resin content. In addition, when measuring the coefficient of thermal expansion, the reason why the measurement was performed without absorbing moisture in the air was because plate-shaped samples are easily affected by moisture, and in some cases, moisture absorption may occur. Therefore, there is a possibility that the measured value may be lower by several percent to several tens of percent.

【table】

[Table] Examples 11 and 12, Comparative Examples 6 and 7 Powdered unsaturated bisimide and diamine were mixed with carbon black and carnauba wax in the proportions shown in Table 3, and then Fused silica treated with the amount of silane coupling agent indicated in Table 1 was added and mixed. Heat this at 130-150℃
A black sheet was created by melting and kneading with heated rolls, which were then pulverized to obtain a molding material. The obtained molding material was placed in a direct pressure mold heated and maintained at 180 to 200°C, and molded for 20 minutes under a pressure of 150 kg/cm ² to obtain a uniform molded product. This product was heated at 250° C. for 2 hours in a nitrogen atmosphere to obtain a final molded product. The characteristic values of the obtained molded product are shown in the lower column of Table 3.

〔Effect of the invention〕

Since the addition type imide resin composition of the present invention is as described above, it is possible to realize the low coefficient of thermal expansion required in the cutting-edge field.

Claims (1)

[Claims] 1. An unsaturated bisimide in which two moieties containing at least an unsaturated imide ring are bonded to one benzene nucleus in a meta-position to each other, and the following general formulas () and (). [However, if the hydrogen of the naphthalene nucleus in the structural unit represented by the above formula is substituted with at least one selected from the group consisting of an inert alkyl group, a perfluoroalkyl group, a halogen, and a functional group that does not participate in the resin formation reaction. may have been done. ] An addition-type imide resin composition containing at least one of the diamines represented by the following as a resin component.