JPH0485331A - Heat-resistant compound for laminate material and production of laminate material by using said compound - Google Patents

Abstract

PURPOSE:To obtain a compound for a laminate material excellent in heat resistance, humidity resistance and storage stability and desirable for a copper-clad laminate by using an ester imide oligomer of a specified structural formula as the principal component. CONSTITUTION:A heat-resistant compound for a laminate material mainly consisting of a compound of formula I (wherein Ar1, Ar2 and Ar3 are each a bivalent organic group and they may be the same or different from each other; and m is an integer of 1-30). An example of Ar1 is a group of formula II, an example of Ar2 is a group of formula III, and an example of Ar3 is a group of formula IV. This compound is dissolved in an organic solvent to prepare a varnish resin composition and a reinforcement is impregnated with this composition and dried to a predetermined residual solvent concentration to prepare a prepreg. At least one prepreg is interposed between copper foils, and the assemblage is integrally molded under applied heat and pressure to prepare a doubly copper-clad laminate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a compound for heat-resistant laminate materials having excellent heat resistance, moisture resistance, and storage stability, and a heat-resistant laminate material using the same.

[Conventional technology and issues to be solved]

In recent years, the development of electronic devices has been remarkable, and copper-clad laminates have been used in a wide variety of ways, and those with excellent properties are required. In particular, as wiring becomes more dense, wiring boards become more multilayered and through-holes become smaller in diameter, there is a need for copper-clad laminates that have good workability, such as less smearing during drilling.

On the other hand, with the demand for improved productivity and lower costs, increasingly strict processing conditions are being added to the wiring board mounting process, such as hot air rehaler and flow soldering. Among these, copper-clad laminates serving as substrates are required to have better heat resistance and moisture resistance than ever before.

In recent years, in order to meet these demands, in place of epoxy resin, which is generally widely used for copper-clad laminates,
Addition-curing polyimide resins have come into use. When this polyimide resin is used for copper-clad laminates, it has the advantage of almost no smearing during drilling, and the heat resistance during processing and long-term tests is significantly improved. Are known. However, conventionally used addition-curing polyimide resins have had various problems as described below.

That is, a product obtained by reacting N,N'-bisimide, an unsaturated dicarboxylic acid, with diaminodiphenylmethane is excellent for use in laminates. There is a problem that the usage time is short. Furthermore, the toxicity of diaminodiphenylmethane to living organisms may pose a problem. In addition, products containing N,N'-bisimide, an unsaturated dicarboxylic acid, and diaminophenol as reaction components exhibit well-balanced properties and excellent processability for laminated boards, but are said to have poor moisture resistance. There are some problems, for example, for long-term storage of the obtained laminate, special attention must be paid to moisture absorption, and furthermore, unsaturated dicarboxylic acid N, N'-
Products reacted with bisimidoaminobenzoic acid are suitable for use in laminates, but they have poor solubility in low-boiling point solvents and have problems when applied to glass cloth, etc. when making prepregs. Furthermore, there were other problems such as the need to be careful in storing the resin solution.

[Means to solve the problem]

In view of the above circumstances, the present inventors have developed these technical gI
! The present invention was developed as a result of extensive research to solve the problem.

That is, the first aspect of the present invention is the general formula (I) (wherein Ar, Arz, and Ar:+ are divalent organic groups, and Ar, Art, and Arz may be the same or different. m may be an integer of 1 to 30.

) The second aspect of the present invention is to prepare a varnish-like resin composition by dissolving the compound in an organic solvent, and then reinforcing the compound. A prepreg is prepared by coating and impregnating the material with the varnish resin composition and then drying it to a predetermined residual solvent concentration.
Each content is a method of manufacturing a double-sided copper foil laminate, which is characterized by sandwiching one or more sheets of copper foil between two sheets of copper foil and integrally molding them by heating and pressing.

First, the method for producing the thermosetting compound of the present invention will be described.

The required amount of para-toluenesulfonic acid chloride C or TsCl in an inert gas atmosphere such as argon or tin
It is written as ) was weighed out and the reaction system was cooled to room temperature or lower, preferably 10°C or lower, more preferably water-cooled, and then pyridine was added dropwise from a syringe while being careful not to generate heat. After sufficient reaction, a calculated amount of trimellitic anhydride (hereinafter referred to as TMA) is dissolved in an aprotic polar solvent and then added. Thereafter, the diol [1] HOArz-OH (U) [1] represented by the general formula (It) (in the formula, Art represents a divalent organic group) was cooled with water and treated with the same abrogated polar solvent as above. Add after dissolving. In order to complete the reaction, the reaction is appropriately carried out at room temperature. Here, in order to obtain a copolymer, the general formula (I[[
) etc. It is also possible to add an organic tetracarboxylic dianhydride [2] ]111 [2] (wherein, Ar represents a tetravalent organic group). Next, the reaction system was ice-cooled again, and the general formula (IV
) diamine [3]HJ Ar+ NHz
(IV) [3] (In the formula, Ar+ represents a divalent organic group.) is added.

At this time, it is important to add a calculated amount of diamine in advance so as to obtain a telechelic oligoester amic acid solution terminated with amino groups at both ends. After the oligoester amic acid solution is sufficiently reacted, the reaction is continued while the reaction system is heated to 60°C.

Thereafter, the aromatic acid anhydride represented by the general formula (V) [4] [4] (where Ars represents a divalent organic group) is prepared by dissolving the terminal amino group in the same aprotic polar solvent as above. , ) terminated with oligoester amine citric acid represented by the general formula (Vl) (where Ar, , Arz are divalent organic groups, Ar3 is 1
Ar+, ^r, and Ar may be the same or different types, and m is an integer of 1 to 30. ).

Finally, in order to thermally ring-close and dehydrate the above amic acid solution, a non-solvent is added, and then the general formula (I
) into an ester imide oligomer.

Here, the nonsolvent to be used can be aromatic hydrocarbons such as xylene, toluene, and Hensen without any particular restriction, but Hensen is preferably used. In the reaction, water to be azeotropically distilled off is refluxed using a Dean-Stark reflux device until the stoichiometric amount of water for the reaction is collected. After the reaction, the polyimide solution is poured into water or an alcoholic solvent with vigorous stirring to precipitate the polyimide as a powder. The powder is collected by filtration and then dried at 80° C. under reduced pressure for 48 hours.

As the organic tetracarboxylic dianhydride used in the present invention, organic tetracarboxylic dianhydride having any structure can be used, but the Arn group in the above general formula (I) is a tetravalent organic group, Specific examples of the Δr4 group, which is preferably an aromatic group, include the following.

C.F.

CF,l These organic tetracarboxylic dianhydrides may be used alone or in combination of two or more. More specifically, from the viewpoint of balance of properties, at least one of the following may be used as the main component. suitable.

The diol used in the present invention has the general formula (II) HOA
rz O) I (II) [±] (In the formula, Ar2 is a divalent organic group), and Arz of the diol compound (earth) can essentially be any divalent organic group. Specifically, the diamine used in the present invention is represented by the general formula (IV) (wherein Ar is a divalent organic group), and ^r1 of the diamine compound [1] is a divalent organic group. Anything can be used, specifically, .

Examples include CF3, but aromatic groups are preferable, and specifically, it is preferable to have at least one or more of the following as the main component.

The aromatic acid anhydride used in the present invention for terminal termination has the general formula (V), etc., but in terms of cost and handling, it is particularly preferably represented by [4], and the aromatic acid anhydride is An example of the material [earth] Ar is as follows.

Examples of aprotic polar solvents used in the production reaction of polyamic acid solutions include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, N
, N'-dimethylformamide, N,N'-diethylformamide, and other formamide solvents; and N,N'-dimethylacetamide, N,N'-diethylacetamide, and other acetamide solvents. These solvents can be used alone or as a mixed solvent of two or more. Furthermore, it can also be used as a mixed solvent with a non-solvent for polyamic acid such as methanol, ethanol, isopropanol, Hensen's methyl cellosolve, etc., along with these aprotic polar solvents. Preferably, it is desirable to use dimethylformamide (hereinafter referred to as DMF) from the viewpoint of the color tone of the produced polymer, yield, etc.

Although the mechanism for producing a cured product with particularly high heat resistance from the reactive ester imide oligomer according to the present invention is not clear, the formation of a benzene skeleton by thermal curing (trimerization) of acetylene or the opening of a Nazick ring , is said to be an effect of thermal polymerization [for example, Takekushiriki, Polymer Processing, Vol. 37, No. 7, p. 347, 19
1988].

In addition, the number average degree of polymerization [DP; P, J, Floats, P
r1nciples of Polymer Chem
istry:CornellUniversity
Press: Ithaca, NY, 91 pages,
1953], the polymerization ratio n was set to 1.
~30, preferably 1-25, more preferably 1-2
0 is good. If it exceeds the above range, there will be a drawback that solubility in organic solvents will decrease. Moreover, if it is smaller than the above range, problems will arise in terms of mechanical strength.

When obtaining a cured product from the esterimide oligomer of the present invention, an epoxy resin, an epoxy resin curing agent, a curing accelerator, a filler, a flame retardant, a reinforcing agent, a surface treatment agent,
Pigments, various elastomers, etc. can be used in combination.

Epoxy resin is a compound having two or more epoxy (glycidyl) groups in the molecule, and examples include bisphenol A1 bisphenol F, hydroquinone, resorcinol, flurglycine, tris-(4-hydroxyphenyl)methane, .2. - Glycidyl ether compounds and phenols derived from divalent or trivalent or higher valent phenols such as tetrakis(4-hydroxyphenyl)ethane, or halogenated polyphenols such as novolak derived from tetrabromobisphenol A and brominated polyphenols. , novolac epoxy resin which is a reaction product of phenols such as orthocresol and formaldehyde, aniline, paraaminophenol,
meta-aminophenol, 4-amino-metacresol,
6-amino-metacresol, 4,4'-diaminodiphenylmethane, 8,8'-diaminodiphenylmethane,
4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 14-bis(3-aminophenoxy)benzene, 1゜3-bis(3-aminophenoxy) ) Benzene, 2゜2-bis(4-aminophenoxyphenyl)propane, paraphenylenediamine, metaphenylenediamine, 2.4-1-lyenediamine, 2,6-
Toluene diamine, baraxylylene diamine, metaxylylene diamine, 1,4-cyclohexane-bis(methylamine), 1,4-cyclohexane-bis(methylamine), 5-amino-1(4'-aminophenyl)-1 '
, 8.8-trimethylindane, 6-amino-1-(4
Amine-based epoxy resins derived from -aminophenyl)-1-,8,8-)limethylindane, glycidyl ester compounds derived from aromatic carboxylic acids such as paraoxybenzoic acid, terephthalic acid, isophthalic acid, etc. 5
, 5-dimethylhydantoin, etc., 2.2-bis(3,4-epoxycyclohexyl)propane, 2,2-bisC4-(2,3
-Alicyclic epoxy resins such as epoxypropyl)cyclohexyl]propane, vinylcyclohexene dioxide, 3,4-epoxycyclohexane carboxylate,
Others, triglycidyl isocyanurate, 2,4.6
-triglycidoxy-s-triazine and the like, which may be used alone or in combination of two or more.

Examples of epoxy curing agents include amine curing agents such as aromatic amines and aliphatic amines such as xylylene diamine, polyphenol compounds such as phenol novolak and cresol novolac, and hydrazide compounds.
It can be used as a species or in combination of two or more species.

As a curing accelerator, benzyldimethylamine, 2.4.
6-1-Lis(dimethylaminomethyl)phenol, 1
．． Amines such as 8-diazabicycloundecene, 2-
Examples include imidazole compounds such as ethyl-4-methylimidazole, boron trifluoride amine complexes, and these may be used alone or in combination of two or more.

Addition of elastomers to improve mechanical strength is also effective. Specifically, the elastomer can be exemplified by the following.

F (X+Y=3) R: -COOH(CTBN CTB) COOCH
zCHCHzOCOCH=CHt (νTBN)H The elastomer described above is 5ilastic (LS
-420), Sylgard (I84) from Dow Corning, Hiker ATBN (I300x1
6 etc.), CTB (2000X162), Cr8N
(I300x13.1300x8.1300x31)
, νTBN (I300X23) is from ■Ube Industries, 3
F is manufactured by Monsando.

Further, flame retardants and inorganic fillers may be appropriately blended to impart flame retardancy. The inorganic filler used is water-insoluble and insulating.

Examples include metal oxides such as silica, alumina zirconia, titanium dioxide, and zinc white; magnesium hydroxide;
Metal hydroxides such as aluminum hydroxide; natural minerals such as talc, kaolin, mica, wollastonite, and clay minerals; insoluble salts such as calcium carbonate, magnesium carbonate, barium sulfate, and calcium phosphate; these may be used singly or in combination. Used in combination of more than one species.

As reinforcing materials, woven fabrics made of carbon fiber, glass fiber, aramid fiber, liquid crystal polyester fiber such as Hectra, polybenzothiazole (PBT) fiber, alumina fiber, etc.
Examples include nonwoven fabric, cloak, paper, or a combination thereof. It is also effective to treat these reinforcing materials with a silane camping agent in order to impart adhesion.

Next, a typical coating process will be explained using an example.

A uniform varnish-like resin composition is obtained by dissolving and stirring the ester imide oligomer represented by the general formula (I) in a predetermined amount of an organic solvent to a predetermined resin concentration. After coating and impregnating the resin composition produced in this way on a reinforcing material such as glass cloth, glass nonwoven fabric, glass paper, etc., the resin composition is dried in a hot air circulation drying oven at 50 to 250°C, preferably 50 to 250°C.
A heat-resistant laminate prepreg is produced by setting and drying the furnace residence time within a temperature range of 0° C., more preferably 100 to 200° C., so as to achieve a predetermined residual solvent concentration.

Examples of the organic solvent used include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, N,N'-dimethylformamide, N,N'-
Formamide solvents such as diethylformamide, N, N
Examples include acetamide solvents such as '-dimethylacetamide and N,N'-diethylacetamide; ether solvents such as dimethyl ether, diethyl ether, and dioxane; and ketone solvents such as acetone and methyl ethyl ketone. These can also be used alone or as a mixed solvent of two or more. Furthermore, in addition to these organic polar solvents, it can also be used as a mixed solvent with alcoholic solvents such as methanol, ethanol, and isopropanol, Hensen, methyl cellosolve, and the like.

The resin concentration at the time of dissolution and dilution in an organic solvent is 5 to 75% by weight, preferably 15 to 75% by weight from the relationship with the resin concentration at the time of prepreg.
It is desirable to use it in an amount of 65% by weight, more preferably in a range of 35 to 65% by weight. The concentration of residual solvent in the prepreg is 1 to 20% by weight, preferably 1 to 1% by weight based on residual solvent/resin ratio calculation.
It is desirable to adjust the amount to 0% by weight, more preferably from 1 to 5% by weight. If it is larger than the above range, a problem arises in that the mechanical properties of the laminate after prepreg molding are low. Moreover, if it is smaller than the above range, the residual solvent will volatilize during prepreg molding, resulting in the inconvenience that voids will occur.

Next, a method for producing a double-sided copper-clad laminate using the heat-resistant prepreg obtained as described above will be described.

Adjust the number of copper foils and prepregs to achieve the desired thickness. A double-sided copper-clad laminate can be created by inserting a specified amount of copper foil or prepreg between two stainless steel plates with mirror-finished surfaces, and then heating and pressurizing the material for a specified period of time and under pressure. Further, it is also effective to use after-cure in combination to improve mechanical strength.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples in any way.

Example 1 A 1 liter 40 flask was equipped with a three-way stopcock, a Dane-Stark distiller, a Dimroth reflux condenser, and a syram cap. The reactor was dried under reduced pressure. 14.9g (
After adding 78 mmol of TsCl to the reaction system, the reaction system was sufficiently purged with argon. The reaction system was ice-cooled, and 30 milliliters of dry pyridine was added, being careful not to generate heat. 15g (
78 mmol) of TMA and 110 ml of dry D
After completely dissolving in MF, it was added for 30 minutes. After continued reaction at that temperature, 30 ml of dry DM
13.1 g (39 mmol) of aromatic diol dissolved in F was added dropwise while cooling with water. After 30 minutes, the ice bath was removed, and the reaction was continued at room temperature for 1 hour. After that, the reaction system was cooled on ice again, and then added to 50 milliliters of dry DMF for 26.
1 g (78.0 mmol) of aromatic diamine was added. After 30 minutes, the ice bath was removed, the reaction system was heated to 60°C in an oil bath, and the reaction was continued for another 30 minutes. 13 in 10ml dry DMF
．． 4 g (78.0 mmol) of aromatic acid anhydride was added and reacted for 2.6 hours. After that, add 200ml of dry benzene to 145℃ (bath salt).
1.4 milliliters (theoretical amount; 1.4 milliliters) of reaction water was distilled off azeotropically. After the reaction, methanol 10
00d! The reaction solution was poured into the container to precipitate the ester imide oligomer. The precipitated ester imide oligomer was filtered under reduced pressure and dried in vacuo at 80°C for 48 hours to obtain 56.0 g (yield: 97.1%) of a pale yellow powder.

165 g of the obtained ester imide oligomer was added to DMF.
It was dissolved in 200 g (resin concentration: 45% by weight/DMF). 20 x 20 CI11 glass cloth (10 to WEA-18
5F117i (manufactured by Nittobo) were impregnated with 16 sheets. Dry in a hot air circulation drying oven at 120°C for 85 minutes to achieve a resin concentration of 38.9% by weight (per glass cloth) and a residual solvent concentration of 4.
．． A 2% prepreg was prepared.

Electrolytic copper foil (35 μm
, 3EC, ■Made by Mitsui Kinzoku Kogyo) sandwiched between two sheets and heated to 180℃
- A double-sided copper-clad laminate with a thickness of 121 m was obtained by integral molding under heating and pressure under conditions of 2 hours and 25 kg/d.

Example 2 Aromatic diol 13.1 g (39 mmol) Aromatic diamine 22.9 g (78 mmol) Acid anhydride 12.8 g (
Using 78 mmol), the reaction was carried out under the same conditions as in Example 1, in which the reaction was carried out at 60''C for 3.5 hours, to obtain 42.1 g (yield: 94.4%) of ester imide oligomer.

Furthermore, a double-sided copper-clad laminate having a thickness of 911I11 was obtained using 165 g of the above esterimide oligomer under the same conditions as in Example 1.

Example 3 Using 9.75 g (39 mmol) of aromatic diol,
The reaction was carried out under the same conditions as in Example 1 except that the reaction was carried out at 60°C for 3.5 hours, and the ester imide oligomer was
．． 2g (yield: 91.3%) was obtained.

Furthermore, a double-sided copper-clad laminate having a thickness of 13 mm was obtained using 165 g of the above ester imide oligomer under the same conditions as in Example 1.

Example 4 6.16 g (39 mmol) of aromatic diol
OH Aromatic diamine 37.6 g (78 mmol) Aromatic diamine 19.3 g (78 m+J-r-l) Acid anhydride 13
．． The reaction was carried out under the same conditions as in Example 1, except that 4 g (78 mmol) of acid anhydride and 13.4 g (78 mmol) of acid anhydride were reacted at 60°C for 3.5 hours, and 65.2 g of ester imide oligomer was used. (Yield: 92.9%).

Furthermore, a double-sided copper-clad laminate having a thickness of 12+ nm was obtained using 165 g of the above ester imide oligomer under the same conditions as in Example 1.

Comparative Example 1 165 g of a commercially available imide oligomer was dissolved in 200 g of DMF (resin concentration: 45% by weight/DMF). 20X2
0c+n glass cloth (WEA-I B K105F11
7; ■Nittobo Co., Ltd.) 16 sheets were impregnated. Dry in a hot air circulation drying oven at 120°C for 85 minutes to a resin concentration of 31.2.
A prepreg with a residual solvent concentration of 9.4% by weight (per glass cloth) was produced.

Electrolytic copper foil (35 μm
, 3EC, ■Mitsui Kinzoku Kogyo) sandwiched between two pieces 220°
A double-sided copper-clad laminate having a thickness of 10 mm was obtained by integral molding under heating and pressure under the conditions of C, 2 hours, and 25 kg/c+11.

Table 1 shows the physical properties of the copper-clad laminates obtained in Examples 1 to 4 and Comparative Example 1.

Table 1 [Effects of the Invention] The compound for heat-resistant laminates of the present invention enables the production of heat-resistant laminate prepregs with high moisture resistance and excellent storage stability, and furthermore, the prepregs can be used industrially. high value,
It enables the production of laminates such as double-sided copper-clad laminates with excellent moisture resistance and heat resistance, and is extremely useful.

[Note] ml JI3-6481 Rate 2 ■Toyo Seiki type Rheolograph Solindo (DTMA)
Measurement rate 5 JIS method - blistering after soldering bath (260°C, 130 seconds) was observed.

○: Good (no blister), ×: Bad (with blister) 5
Pressure (Cuncates): 121°C 12 atm,
After 5 hours of treatment, blisters were observed after a solder bath (260°C, 130 seconds).

○: Good (no blisters), ×: Bad (with blisters) Patent applicant Kanebuchi Chemical Industry Co., Ltd.

Claims (1)

[Claims] 1. General formula (I) ▲Mathematical formula, chemical formula, table, etc.▼(I) (In the formula, Ar_1, Ar_2, Ar_3 are divalent organic groups, and Ar_1, Ar_2, Ar_3 are Each compound may be of the same kind or different kinds. m is an integer of 1 to 30. 2. The heat-resistant laminate compound according to claim 1, wherein Ar_1 is selected from the following groups; Compound for heat-resistant laminate materials; ▲ Includes mathematical formulas, chemical formulas, tables, etc. ▼ 4. Compound for heat-resistant laminate materials according to claim 1, in which Ar_3 is selected from the following groups; ▲ Includes mathematical formulas, chemical formulas, tables, etc. ▼ 5 , a varnish-like resin composition is prepared by dissolving the compounds described in items 1 to 4 in an organic solvent, and then a reinforcing material is coated and impregnated with the varnish resin composition, and then a predetermined residual solvent concentration is applied. Dry to create a prepreg, sandwich one or more sheets of the prepreg between two sheets of copper foil,
A method for manufacturing a double-sided copper foil laminate, which is characterized by integral molding by heating and pressing. 6. The manufacturing method according to claim 5, wherein the concentration of the varnish-like resin composition is 5 to 75% by weight. 7. The manufacturing method according to claim 5 or 6, wherein the residual solvent concentration of the prepreg is 1 to 20% by weight based on the resin.