JPH03185066A - Thermosetting resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (,) Industrial Fields of Use The present invention is applicable to heat-resistant materials used in the manufacture of printed wiring boards or molded products that have excellent heat resistance, good workability, and excellent electrical properties. The present invention relates to a curable resin composition.

(b) Conventional technology In recent years, the usage conditions for materials used in fields such as electrical and electronic equipment, parts, automobiles, and aircraft have become increasingly harsh.For example, printed wiring boards are becoming more multilayered and more densely packaged. It tends to improve heat resistance, dimensional stability,
Furthermore, a lower dielectric constant is required. Currently, it is particularly heat resistant,
As fatty materials with excellent moldability, addition-polymerizable aromatic maleimide-based O (fats) that do not produce volatile substances during curing have come to be widely used.

Various aromatic maleimide resins have been developed, and have been put into practical use by improving moldability, moisture resistance, strength, etc. by using maleimide alone or by modifying it with other thermosetting resins such as polyamines (for example, Kosho 46-232
Publication No. 50).

However, this device has poor operational reliability under high-temperature conditions, and the reality is that it cannot meet recent demands for higher density, higher multilayer, smaller size, and higher W1 performance of devices.

Therefore, as disclosed in Japanese Patent Publication No. 62-115754, at least the general formula [11 (where Ar+ and 1/A r 2 are , represents a single bond, or 0%C
H2, C(CH3)2, C(CF3)2.00%51
represents any group selected from SO2, both of which may be the same or different; Ar3 represents (here, X and Y are It has been proposed to coat a polyimide tea tree m composition having a repeating unit represented by ) in its molecular skeleton.

(c) Problems to be Solved by the Invention However, this material has a high dielectric constant, poor flexibility, and poor moldability.Also, it has a high water absorption wheel, low moisture resistance, and There are many issues to be solved, such as the low decomposition temperature, and it cannot be said that its application and development have been sufficiently carried out.

Also, as mentioned above, this product is suitable for electronic products such as heat resistance, moldability, and electrical properties! l! t, balance of properties required in the electrical equipment field such as dimensional stability (coefficient of linear expansion), thermal decomposition temperature, glass transition temperature, solvent resistance (triclean resistance), dielectric constant, and adhesive strength to metals. There are some things that are difficult to deal with.

In particular, in order to increase flexibility or improve moldability, selecting a mo/mer or mixing an epoxy resin, etc. lowers the glass transition temperature, increases the coefficient of linear expansion, and increases the dielectric constant. This has led to the problem that the desired high performance and high reliability of the applied products cannot always be sufficiently achieved.

The present invention was completed in order to solve the above technical problem, and includes a specific polyazomethine structural unit and a specific polyimide (or amic acid) structural unit contained in the molecular skeleton, or a combination of these. By modifying a specific polyazomethine by reacting a thermosetting resin m-acid containing a specific bismaleimide in its structural unit by heat curing, it is possible to improve heat resistance and dimensional stability, and to improve heat resistance and dimensional stability. It is an object of the present invention to provide a thermosetting resin composition that can increase the dielectric constant and thus enable high-multilayer and high-density packaging of electronic components.

(d) Means for Solving Problem i# In order to achieve the above object, the thermosetting resin composition of the present invention has the general formula [A] [A]+N=CH-R, -CIl=N- It is also possible to obtain even higher solubility by selecting 82-)- and general formula [B].

or higher soluble solvent or polymer film, tMIl
In 1, the photochromic reaction of spiropyrans proceeds as shown in the following equation.

The present invention provides a thermosetting resin composition containing a heat-stable repeating unit.

The thermosetting resin composition of the present invention can be obtained by the following method.

That is, the structural unit represented by the general formula [A] can be obtained by a method for synthesizing polyazomethine, for example, by reacting a dialdehyde with a diamine, and the structural unit represented by the general formula [B] can be obtained by a method for synthesizing polyimide, for example, by reacting a dialdehyde with a diamine. Obtained by reaction of acid anhydride and diamine.

As a method for obtaining the thermosetting resin composition of the present invention, the above-mentioned raw materials 7 amine, dialdehyde and tetracarboxylic acid anhydride are polar in solvent, acetic anhydride,
The polyschiff base structural unit represented by the general formula [AI and the polyamic acid structural unit which is the precursor of the general formula [B]] are reacted in the presence or absence of a dehydrating agent such as sulfuric acid or phosphoric acid, and a dehydration reaction accelerator. You can get DI.

By dehydrating and ring-closing this precursor, it is possible to obtain the thermosetting resin composition of the present invention having the corresponding polyimide structural unit [B] and direct structural unit [AI].

These synthesis methods are not particularly limited, and any known polyimide synthesis method may be employed as appropriate depending on the use and purpose.

For example, a dialdehyde, a tetracarboxylic anhydride, and diamines in an amount approximately equimolar to the total amount thereof are dissolved in an organic solvent at a concentration of about 10 to 40% by weight. By stirring at room temperature for several hours to several tens of hours, the precursor solution having the structural unit of the general formula [DI and the general formula [AI] is obtained as varnish 7. This varnish can be used as a printed circuit board or a molded product by coating, molding, and heat treatment to dehydrate and ring-close the thermosetting resin composition of the present invention.

Further, the thermosetting resin composition of the present invention, namely - general formula [A
When a composition having a structural unit represented by I and a structural unit represented by general formula [B] is soluble in a solvent (particularly in the case of the present invention, it is often soluble), the composition having a structural unit represented by general formula [DI] The thermosetting resin composition of the present invention can be obtained by dehydrating and ring-closing a precursor varnish containing a structural unit, for example, by Dean-Stark azeotropic dehydration method.

Examples of the solvent include N-methyl-2-pyrrolidone (N M P L trimethyl sulfoxide (DMSO)).
, N, N-trimethylacetamide (DMAc), N, N
-Aprotic polar solvents such as dimethylacetamide (DEAe) and N,N-dimethylformamide (DMF) are used, and depending on the composition, they may also be soluble in general-purpose nonpolar solvents such as toluene and xylene. be.

In the above general formula [AI, R and R2 represent a divalent aromatic group, such as -@-sO.(□, BetoS-@-, o o.

R2 may be the same but different etc., and You can leave it there.

However, in the present invention, it is preferable that at least one of the above R and R2 groups contains a perfluoroalkylene group or a 77-ken group. The reason for this is the low dielectric constant mentioned in iiq, and it is soluble in solvents, so there is no need for dehydration and ring closure.In other words, especially during molding, water does not come into contact with the soil, so foaming, cracks, etc. do not occur, and workability is improved. This is because it is good.

In addition, in the above general formula [BJ, R1 is the above R and R
It is the same as 2. Furthermore, in the above general formula [BJ, R represents a tetravalent aromatic group, for example, in the above general formula [BJ, at least one of Ro and R4 may contain a perfluoroalkylene group or a fluorine group. is preferable for the same reason as above.

The thermosetting resin composition of the present invention can be molded into any of fibers, films, and general resin moldings. It is also possible to pour the polymerization solution into a non-solvent such as water or methanol, wash and dry the polymer, and then mold it.

By the way, in the component ratio in the thermosetting resin composition of the present invention, [A]/([A]+[B])X 1
00=1-45 mol%, further 2-40 mol%, special 5-45 mol%
The content is preferably 35 mol%.

If 1 mol% is less than 6<i, curing will be insufficient, resulting in poor solvent resistance.On the other hand, if it exceeds 45 mol%, the dielectric constant will increase and flexibility will be low, leading to brittleness. This is not desirable because there is a tendency to

By the way, as a method for copolymerizing the components described in "U", each mo/mer component may be charged and polymerized at once, or the general formula [A
] and the general formula [BJ
When synthesizing the components constituting the structural unit represented by the formula [A
] or the other component of the general formula [BJ] may be added and polymerized, and then the remaining components may be added and polymerized.

In either method, heat resistance, which is the objective of the present invention,
It is possible to obtain a product with excellent solvent resistance, reduced #i expansion coefficient, and low dielectric property.

Next, the hardening treatment after molding in the present invention will be explained.

In the present invention, the curing treatment is a condition under which a crosslinking reaction of the thermosetting resin composition occurs. - A thermosetting resin composition molded into the shell can be hardened by heat treatment, preferably a copolymer resin composition containing bismaleimide (general formula [C1), which will be described later.

The heat treatment is performed at the glass transition temperature (T) of the thermosetting resin composition.
g) It is carried out at the above temperature, preferably (Tg - 20°C)
The temperature is above (Tg+150°C) or below.

In this way, when bismaleimide is included, the heat treatment temperature can be lowered, the curing reaction is also significantly promoted, and the heat treatment process can be simplified. In this case, although it depends on the type and amount of bismaleimide contained, the temperature can usually be relaxed to the above-mentioned Tg±100°C.

Next, the bismaleimide used in the present invention will be explained.

It is represented by the general formula [C] (Rs is the same as R, R2, and R4 above, and D represents an organic group having a divalent unsaturated bond). It is obtained by known methods and is obtained by reaction of an unsaturated nocarboxylic acid anhydride with a diamine.

Specific examples include the following.

obtained by the reaction of a derivative of and cyamine, (b)
(c) Nanotsuclic anhydride or derivatives thereof, such as methyl nadic anhydride, oxynadic anhydride, methyl Examples include reaction products of cyamine and oxynanodic anhydride, hexachloronadic anhydride, and the like.

for example Examples include.

In the present invention, a copolymer I having a structural unit represented by the general formula [A] and a structural unit represented by the general formula [B] (a combination of a rI'6 compound and an acid compound of a bismaleimide represented by the formula [C]) is used. The blending ratio is not particularly limited, but general formula [A]
The bismaleimide of [C] is contained in a range of 0.05 to 20 moles per mole of the structural unit represented by the formula, preferably 0.05 to 1 mole.
It is preferably 0 mol, particularly preferably in the range of 0.5 to 5 mol.

Bismaleimide represented by the general formula [C] is not particularly required unless there is a problem with high temperature and relatively long treatment in the curing process; however, it is usually treated with relatively low temperature and short time. Since it is more convenient if it can be carried out, it is usually preferable to mix 0.05 mol or more per 1 mol of the structural unit represented by the general formula [A]. On the other hand, if the amount exceeds 20 moles per mole of the structural unit represented by the general formula [A1], the resin becomes brittle after the curing reaction, the heat resistance deteriorates, and the dielectric constant and loss increase, which is undesirable.

Although the bismaleimide [C] acid component used in the present invention can be blended and supplied as is, the blended
It may be supplied in a so-called prepolymer state, which is pre-reacted at a temperature of 0° C. or lower.

In the case of the present invention, it has a sufficiently low coefficient of linear expansion in the curing reaction described below even without being made into a prepolymer, and has high strength and low dielectric properties.

In the present invention, the thermosetting resin composition can be supplied in the form of a so-called varnish, which has good storage stability at room temperature, that is, has a long pot life.

Examples of methods for curing the thermosetting resin composition of the present invention include DMSO, DMF, DMAc, NMPS nochloroethylene, tetrachlorethylene, cloflebzene,
A solution of the composition in a solvent such as dichlorobenzene, cyclohexanone, nooxane, or an alkylated aromatic hydrocarbon MIBK or MEK can be cast, the solvent can be evaporated, and the composition can be cured. At this time, a small amount of organic peroxide such as di-t-butyl peroxide, nolauryl peroxide, dicumyl peroxide, t-butylcumyl peroxide, t-butyl benzoate peroxide is added in an amount of 0.01 to 5% by weight based on the total amount. May be used in It is also possible to use curing accelerators other than organic peroxides or additives that favor curing.

The curing temperature is 10% in air or in an inert gas atmosphere.
By heating at 0 to 350'C for several minutes to several tens of hours, a network-bonded, insoluble and infusible cured product can be produced.

The reticulated, infusible, cured product can generally be formed into shaped rods, planar structures, laminates, or composites simultaneously with its manufacture. In this case, additives, fillers, plasticizers, etc. commonly used in the curable plastics industry are added to the thermosetting zero-fat composition.
Pigments, dyes, mold release agents, and flame retardants can be added.

As the filler mentioned above, for example, glass fiber, mica, quartz, kaolin, colloidal silicon dioxide or metal powder can be used, and as the mold release agent, for example potassium stearate can be used.

Molding is done in air or in an inert gas atmosphere with a weight of 1 to 200 kg.
/c1 pressure, 100-300"C1 especially 170~
This can be done by heating at 250°C for several minutes to several tens of hours. The molded image thus produced already has sufficient mechanical strength and can be completely hardened outside the press in an oven at 200 DEG -280 DEG C.

When a prepolymer is produced from a thermosetting resin composition, it can also be ground into a fine powder and used as a surface protection agent after the vortex sintering process.

Further, the thermosetting resin composition can be dissolved using an appropriate solvent and used for producing a laminate.

In this case, this resin solution is impregnated into a porous planar structure such as a woven fabric, fiber mat, fiber wreath, lath fiber mat or glass fiber weave, and the solvent is removed by a drying process. In a press, especially at 120-250°C, 5-20
Further curing is carried out at a pressure of 0 kg/cm". The laminate is precured in a press and the resulting product is cured in an oven at 200 kg/cm".
Post-processing curing is also possible at ~300°C until optimal use properties are achieved.

In the present invention, in particular, in a copolymer of a structural unit represented by general formula [A] and a structural unit represented by general formula [B], at least one group of each structural unit is a perfluoroalkylene group or a fluorine group. In particular, R,
At least one of R2 and at least one of R, and R4 contains a perfluoroalkylene group or a fluorine group, and furthermore, in the unsaturated bismaleimide represented by the general formula [C], the group R5 contains a perfluoroalkylene group or a fluorine group. or fluorine groups, the dielectric constant is particularly low, and even if it has a structural unit represented by the general formula [B], it is soluble in solvents, so it has good processability. It does not generate any by-products, so it has excellent cracking resistance during through-hole processing and hanging liquid immersion when used as a substrate, and has excellent adhesion to aluminum and copper, low water absorption, and good electrical properties. Useful.

Examples of such groups include (n: an integer of 1 to 6) for R, R2, R1 and R1.

(e) Effect The thermosetting resin composition of the present invention has the above structure, has good solubility of the resin composition, and can be easily impregnated into glass cloth, etc. By blending the compound, it is cured by heating at low temperatures and in a short period of time, and is also insolubilized, which has the effect of improving solvent resistance.

In addition, the cured product of this thermosetting resin composition has low hygroscopicity and good electrical properties, as well as good adhesive strength and excellent corrosion resistance and heat resistance. Furthermore, the thermosetting resin composition of the present invention has excellent characteristics as a polyimide, while also suppressing crosslinking and curing reactions (does not produce water as a by-product at the addition temperature) due to the structural unit represented by the general formula [A]. In particular, it has the effect of curing and insolubilizing solvent-soluble polyimide (not amic acid) by introducing fluorine groups.

(r) Examples Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

Example 1 Preparation of thermosetting resin composition (copolymer resin) solution ■ 0.02 mol of tele7talaldehyde [TPA is abbreviated as 1 ■ 2,2-bis(3,4-nocarpoxyphenyl) hexa Fluoropropanedioic anhydride [abbreviated as 6F D A] 0
．． 08 mol 2.2-bis(4-(4-amino/phenoxy)7enyl 1 hexafluoropropane 0.10 mol).

is N-methyl-2-pyrrolidone IN M P and approximately 120
Dissolve in 0g. Next, this mixture was slowly stirred under an N2 atmosphere, a small amount of toluene was added, the temperature was raised to 150° C., the water produced was removed by azeotropy, and the toluene was further removed to obtain an NMP solution of the copolymer resin.

Heat Treatment The obtained NMP solution of the copolymer resin was applied uniformly onto a lath plate, and heated at 120"C for 1 hour and at 170"C for 2 hours.
The film was dried by heating for 2 hours at 220"C, 14 hours at 270"C, and then 1 hour at 300C.

The resulting film had the following properties: lath transition temperature (Tg), coefficient of linear expansion (1.5% thermal decomposition temperature (Td), trichloride resistance and IOK, dielectric constant (ε) at Hz, tan δ, copper M adhesion strength) was measured.

The results are shown in Table 1.

Examples 2 and 3 Various monomers shown in Table #1J1 were reacted in the same manner as in Example 1 at the blending ratios shown in Table 1 to prepare films.

Table 1 shows the properties of the obtained film.

Examples 4 to 7 Various monomers shown in Table 1 were reacted in the mixing ratios shown in Table 1 in the same manner as in Example 1 to obtain NMP solutions of copolymer resins. Next, add BAPF-MI to this solution and add the first
They were contained in the proportions shown in the table.

Using the obtained solutions of thermosetting resin compositions, films were prepared by reacting in the same manner as in Example 1 (however, the final heat curing temperature was appropriately changed to Tg+20 or higher).

Table 1 shows the properties of the obtained film.

Comparative Examples 1 and 2 Films were prepared by reacting the various monomers shown in Table 1 in the same manner as in Example 1 at the mixing ratios shown in Table 1.

Table 1 shows the properties of the obtained film.

Comparative Example 3 Various monomers shown in Table 1 were reacted in the mixing ratios shown in Table 1 in the same manner as in Example 1 to obtain an NMP solution of a copolymer resin. Next, add BAPF-MI to this solution.
It was contained at a blending ratio of 25 mol per 1 mol of PAL.

Using the solutions of the obtained thermosetting resin compositions, each film was produced by reacting in the same manner as in Example 1.

Table 1 shows the properties of the obtained film.

Comparative example 4 In Example 2, TPAL ll did.

(Margin below) In Table 1, the copper foil adhesive strength was measured by the following method.

That is, each solution obtained was soaked in a glass cloth (WE-0 manufactured by Nittobo Co., Ltd.).
9-F 104) and dried at 170°C for 10 minutes to obtain a prepreg. tM on the top and bottom of these four prepreg sheets
M (Nikko Gould Co., Ltd. 1i! JTC-18μ) and 2
After heating and pressurizing at 00℃ for 120 minutes, heating for 30 minutes under normal pressure.
After curing at 0° C. for 60 minutes, a double-sided copper-clad laminate with a thickness of 0.6 mm was obtained. The peel strength between the copper foil and the lath cloth was measured using a tensile tester.

From the results shown in Table 1, the examples have better heat resistance and solvent resistance, lower coefficient of linear expansion, lower dielectric constant, and greater adhesive strength than comparative examples. One thing was recognized.

Furthermore, during molding, there was no by-product such as water during curing, so moldability was good, and no problems such as cracks were observed.

(g) Effect of the invention In the thermosetting resin composition of the invention, the general formula [A]
It is characterized by containing a structural unit represented by the following and a structural unit represented by the general formula [B], and by heating and curing these to react, it improves heat resistance and dimensional stability, and also improves the heat resistance and dimensional stability. Since it is possible to increase the dielectric constant, it has the effect of increasing the number of layers of electronic components and increasing the density of packaging.

Moreover, in the thermosetting resin composition of the present invention, the general formula [
When a specific bismaleimide is added to a resin composition containing a structural unit represented by A] and a structural unit represented by general formula [B], a curing reaction of the resin occurs at low temperature and in a short time. By curing it in this way, heat resistance and dimensional stability can be further improved, and the dielectric constant can be lowered.As a result, it is possible to achieve high multilayer and high density packaging of electronic components, etc. Extremely useful.

Furthermore, in the thermosetting resin composition of the present invention, the curing temperature and opening during curing can be adjusted by adjusting the blending amount of bismaleimide, so no special equipment or special techniques are required for molding, and it is extremely easy to mold. Useful.

Claims (3)

[Claims] (1) A thermosetting resin composition containing a structural unit represented by the general formula [A] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [B] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ In the above general formula, R_1, R_2, and R_4 have ▲ mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas, chemical formulas, tables, etc. ▼, ▲ mathematical formulas, chemical formulas, tables, etc. ▼, ▲
There are mathematical formulas, chemical formulas, tables, etc.▼ (X, Y are single bonds or O, CH_2, C(CH_3),
It represents any one of C (CF_3), CO, S, and SO_2, and both may be the same or different. Z each independently represents at least one of F, Cl, Br, a lower alkyl group of C_1 to C_4 or a fluorinated alkyl group, m
Each independently represents an integer of 0 to 4. ) In the above general formula, R_3 has ▲mathematical formula, chemical formula, table, etc.▼, ▲mathematical formula, chemical formula,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (X, Y, Z are the same as above. l is 0 to 2, n is 0
~3, m represents an integer from 0 to 4. ) (2) In the thermosetting resin composition of claim 1, [A]
A thermosetting resin composition in which /([A]+[B])×100 is 1 to 45 mol%. (3) The thermosetting resin composition of claim 1 or 2 has the general formula [C]▲mathematical formula, chemical formula, table, etc.▼ (However, R_5 represents a divalent aromatic organic group, and D represents an unsubstituted aromatic group. (representing an organic group having a saturated bond.) A thermosetting resin composition containing a compound represented by the following.