WO2006021313A1

WO2006021313A1 - Polymer material for producing laminates and laminate for the printed board circuit industry

Info

Publication number: WO2006021313A1
Application number: PCT/EP2005/008459
Authority: WO
Inventors: Heinz-Gunter Reichwein; Andreas Palinsky; Jörg Scholten
Original assignee: Bakelite Ag
Priority date: 2004-08-24
Filing date: 2005-08-04
Publication date: 2006-03-02
Also published as: DE102004041129A1; TW200616790A

Abstract

The aim of the invention is to provide a polymer material which can be used as a polymer material for producing laminates for the circuit board industry, preferably for producing electrolaminates having only few dielectric losses. For this purpose, a polymer material, especially a polymer mixture is used which consists of a mixture of at least one hydrocarbon resin which is compatible with cyanate esters, at least one cyanate ester and optionally at least one epoxide resin.

Description

Polymer material for the production of laminates and laminate for the printed circuit board industry

The present invention relates to polymer material, in particular a polymer mixture, of a mixture of hydrocarbon resin with cyanate ester and optionally epoxy resin as polymer material for the production of laminates for the printed circuit board industry, preferably for the production of electrical laminates with low dielectric losses. The invention further relates to a laminate for the production of printed circuit boards of this polymer material.

The laminates used in the electrical industry are plastic sheets, which, in simple terms, consist of fabric layers which, in turn, have been coated, for example, with phenolic or epoxy resins. A distinction is made between non-laminated laminates, e.g. to be used as insulating materials, and laminated laminates coated with a metal foil, i.d.R. a copper foil have been pressed and the e.g. to be used as base materials for printed circuit board production.

At present, the materials used for laminate production can be divided into three material classes:

Resins, - Carriers,

Copper foils.

The resins used in the production of laminates are phenolic resins, polyester resins, epoxy resins, bismaleimide / triazine resins, cyanate resins, polyimide resins, but also teflon (polytetrafluoroethylene). The most common carrier systems

BESTÄTäGUNGSKOPlE this includes paper, nonwovens and woven fabrics made of glass or aramid, PTFE fabric and PTFE film. Depending on the application, copper foils made of electrodeposited copper or rolled copper are used for the production of laminates.

For high frequency applications, laminate materials with improved dielectric properties are needed, i. such materials have a low dielectric loss factor tan δ and a low dielectric constant DK.

It is known that polymer materials made of non-polar or poorly polar raw materials have very good dielectric properties. As is known, this is also the case with cyanate esters or blends of cyanate esters and epoxy resins. The disadvantage, however, is that such cyanate ester systems or mixtures thereof are sensitive to hydrolysis, and these

Hydrolysis sensitivity ultimately leads to problems in the processing of these systems and in the storage of intermediates produced therefrom. In addition, such polymer materials or polymer molding materials are very brittle, so that the surface condition of such laminates is often insufficient.

There is therefore still a need for polymer materials which do not have the aforementioned disadvantages, so that they are used as polymer materials for the production of laminates for the circuit board industry, preferably for the production of electrical laminates with low dielectric losses or

Laminates are suitable.

It is known that hydrocarbon resins are thermoplastic polymers which have a mean molecular weight below 2000 and soften over a wide temperature range. Depending on the provenance of

Hydrocarbon resins are usually distinguished between resins of petroleum, resins of coal tar and resins of terpene resins. Here, the petroleum or petroleum resins are the most important group of hydrocarbon resins. With regard to coal tar resins, reference should be made to coumarone-indene resins (also called indene coumarone resins), which are the main representatives of this group are and are the oldest synthetic thermoplastics ever to have found a variety of engineering applications.

In terms of physical properties, the range of hydrocarbon resins ranges from liquids at normal temperature to brittle hard solids, where the color of the resins can vary from almost colorless to dark brown. Due to the property profile of these resins, they may i.a. as binders, tackifiers, enhancers, extenders, film formers and dispersants in a variety of applications, especially in adhesives, rubbers and paints, etc. are used.

Furthermore, it is known that pure hydrocarbon resins have good insulating properties since the values of the dielectric constants are in the range of about 2.3 to 2.8. In addition, hydrocarbon resins are in aromatic and aliphatic solvents, higher ketones, esters, ethers and halogenated

Solvents soluble. In general, hydrocarbon resins are also compatible with a variety of materials, namely, drying oils, plasticizers, styrenes, polyethylene waxes and rubbers, so that such hydrocarbon resins could also find use as additives for reactive polymers. However, it is reported that hydrocarbon resins are not compatible with castor oils, cellulose ethers and esters, as well as epoxy resins and ketone resins (see Ulimann's Encyclopadie der technischen Chemie, 4th Edition, Vol. 12, 539, 540 right column.

It has now surprisingly been found that the object of the invention, namely to provide polymer material, as the polymer material for

Production of laminates for the printed circuit board industry, preferably suitable for the production of low dielectric loss electrical laminates, of polymer material, in particular a polymer mixture consisting of a mixture of at least one cyanate ester compatible hydrocarbon resin, at least one cyanate ester and optionally at least one epoxy resin can be solved. This was surprising inasmuch as it would have been expected that a combination or mixture of hydrocarbon resins with cyanate esters would lead to products which are not suitable for the production of laminates for the printed circuit board industry, since blends of epoxy resins with Hydrocarbon resins can not be used to make such laminates due to the lack of compatibility with each other and the low shelf life of these components and prepregs made therefrom. In contrast, polymer materials or molding materials based on Cyanatestem or blends of cyanate esters and epoxy resins are known as polymer materials for the production of laminate materials.

According to the invention, the polymer materials, in particular polymer mixtures as cyanate ester resins, may comprise at least one compound of the general formula I

R (OC≡N) _n

wherein R is a mononuclear or polynuclear aromatic or alkylaromatic substituted or unsubstituted radical and n is a number greater than 1.

Cyanate ester resins of the general formula II are particularly preferred

where Z = -CN or optionally hydrogen

X = a divalent organic radical, in particular a substituted or unsubstituted linear, cyclic or branched alkyl or benzyl radical having 1 to

10 carbon atoms, where X may be identical or different from each other,

R = inert organic radical, in particular an alkyl, halogen, an ether or

Ester residue m = a number from 0 to 4 a = a number from 0 to 10

The polymer materials according to the invention preferably have cyanate esters with Z = -CN, X = methylene, where a = 0 to 5.

These cyanate ester resins may also contain triazines. By way of example, reference is hereby made to EP 0 794 979 B1, in which such polyfunctional phenolocyanate / phenoltriazine copolymers have been described, to which reference is hereby expressly made. Thus, this document is now part of the description of the polymer blends of the invention. Cyanate ester resins, the

Triazines can be obtained from the company Lonza Ltd., Basel, Switzerland under the product name Primaset®. Products which can be used according to the invention are, for example, Primaset® PT-15, Primaset® PT-30, Primaset® PT-3OS, Primaset® PT-60, Primaset® PT-60S, Primaset® BA-230S, where the cyanate ester resin of the product Primaset® PT- 60 for the inventive

Polymer materials is particularly preferred.

According to the definition given in Elias, Makromolekule, 5th edition, Hüthig and Wepf Verlag, Basel, 1992, Vol. 2, page 606, the terminus technicus "compatibility" is an operative term for the behavior of

Polymer / polymer blends that are not in thermodynamic equilibrium, but which are e.g. behave in terms of mechanical properties as if they were.

Although the properties, in particular of polymer blends, essentially depend on whether the components are thermodynamically miscible or immiscible, the phenomenological concept of "compatibility" can not simply be equated with the thermodynamic concept of miscibility (see Elias, Macromolecules, 5. Edition, Hüthig and Wepf Verlag, Basel, 1990, Vol. 1, page 680). According to the invention is therefore under the term

Compatibility understood that the individual components that can be used for the polymer blends according to the invention, namely

a) Hydrocarbon resins b) Cyanate ester resins of the general formula I. c) optionally epoxy resins

behave in terms of their mechanical or performance properties so that they are suitable as polymer materials for the production of laminates for the printed circuit board industry, preferably for the production of electrical laminates with low dielectric losses.

For the polymer materials according to the invention, in particular polymer blends, it is possible to use all hydrocarbon resins which are compatible with the cyanate ester resins of the general formula IR (OC =N) _n, preferably of the general formula II, ie all known petroleum or petroleum resins, resins from coal tar, in particular the indene coumarone resins and terpene resins are used.

It is also possible with preference to use modified hydrocarbon resins.

Exemplary here are aliphatic and / or aromatic hydrocarbon resins which have been modified by copolymerization with phenol and / or styrene.

Particularly advantageous are thermoplastic hydrocarbon resins based on petro- and carbostämmiger raw materials, which can be obtained from the company RÜTGERS CHEMICALS AG, Duisburg, Germany under the name NOVARES®, preferably aromatic hydrocarbon resins, aliphatic modified, aromatic hydrocarbon resins, phenol-modified aromatic hydrocarbon resins and indene -Cumaron resins. Particular preference is given according to the invention to phenol-modified petroleum-derived hydrocarbon resins, in particular copolymers of unsaturated C9 / C10 aromatic hydrocarbon resins with phenol, which have a softening point (ring & ball) ASTM D3465 95 to 125 [ ⁰ C] and a color (Gardner scale) [50 % in toluene] ISO 4630 5 to 9 are marked and those of the company

RÜTGERS CHEMICALS AG are available under the product name NOVARES®.

In a particularly preferred embodiment, the polymer materials according to the invention, mixtures of at least one compatible with cyanate esters hydrocarbon resin, namely at least one phenol-modified petroleum hydrocarbon resin, in particular at least one copolymer of an unsaturated, aromatic C9- / C10-hydrocarbon resin with phenol, which has a softening point (ring & ball) ASTM D3465 95 to 125 [ ⁰ C] and a color (Gardner scale) [50%]. in toluene] ISO 4630 5 to 9 and under the name

NOVARES® TA 100 is available, with at least one liquid hydrocarbon resin, in particular a styrenated phenolic resin, which by a viscosity at 25 ° C from 400 to 1400 [mPas], an OH content of 7.0 to 7.6 [%] and a Color (Gardener scale) undiluted ISO 4630 of max. 6 is marked. Such liquid styrenated phenolic resins are also available from RÜTGERS CHEMICALS AG under the product name NOVARES® LS 500.

In view of the fact that the polymer materials according to the invention must be suitable as polymer materials for the production of laminates for the printed circuit board industry, preferably for the production of electrical laminates with low dielectric losses, it has been found that particularly good results can be achieved for this application, if the polymer materials according to the invention Hydrocarbon resins, a combination of a phenol-modified petroleum-derived hydrocarbon resin, in particular one

A copolymer of an unsaturated, aromatic C9 / C10 hydrocarbon resin with phenol is, preferably a NOVARES® TA 100 hydrocarbon resin, and a NOVARES® LS 500 styrenated phenolic resin.

In this case, it is advantageous if the weight ratio between the phenol-modified petroleum-derived hydrocarbon resin and the liquid hydrocarbon resin, preferably a styrenated phenolic resin, is in the range from 0.3 to 1.7 parts by weight to 1.7 to 0.3 parts by weight. Preferred is a weight ratio ranging from 0.75 to 1.25 to 1.25 to 0.75

Parts by weight, wherein a weight ratio in which the combination of the hydrocarbon resins consists of equal parts by weight, is particularly preferred. The polymer materials according to the invention, in particular polymer blends, may optionally comprise at least one epoxy resin. In particular, all epoxide compounds which contain more than one epoxide group, ie which are difunctional or polyfunctional, can be used as epoxide compounds. According to the invention, difunctional epoxide compounds are preferred. As higher-functional epoxy compounds, the polymer materials according to the invention may in particular comprise polyglycidyl ethers of novolaks.

Furthermore, the polymer materials according to the invention, in particular polymer blends, may contain further additives, such as e.g. Hardener, solvent, further compatible with the polymeric materials additional resins, accelerators or retarders.

The polymer materials according to the invention, in particular polymer blends, are outstandingly suitable as polymer materials for the production of laminates for the circuit board industry, preferably for the production of electrical laminates with low dielectric losses. In particular, hydrolysis-resistant laminates with low dielectric constants and dielectric loss factors can be produced therefrom, or else storage-stable, relatively moist, insensitive prepregs can be produced therefrom.

Example 1: Resin production

There are 110 kg semi-solid, Haiogenhaltiges epoxy resin based on tetrabromobisphenol-A (eg., Under the trade name "Bakelite® EPR 500" from Bakelite AG, Iserlohn-Lethmate available) as a melt in a stirred reactor with reflux condenser and placed under Stirring and reflux at 125 ⁰ C recorded in 80 kg of ethyl methyl ketone.

The boiling point is set to 110 ⁰ C at the end. At this temperature, 64 kg of phenol-modified, petroleum-derived hydrocarbon resin copolymer of unsaturated aromatic C ₉ / C ₁₀ hydrocarbon resins with phenol (eg that available under the trade name Novares® TA 100 from Rütgers Chemicals AG, Duisburg) are added and the raw material is dissolved in the resin one. Subsequently, 64 kg of styrene / phenol-modified petro-carbohedral hydrocarbon resin (eg that available under the trade name Novares LS 500 from Rütgers Chemicals AG, Duisburg) and 680 kg of cyanate ester are added and dissolved. Finally, the resin is cooled to room temperature.

Example 2: Prepreg Preparation

Support material is a type 7628 glass cloth having a gross weight of about 203 g / m ² . The fabric is conveyed at a rate of 0.8-1.4 m / min through the resin bath with impregnating varnish and through squeezing

Dosing rollers set to a coating weight of 350 g / m ² . The impregnating varnish is composed as follows:

Cyanate ester / hydrocarbon resin / epoxy mixture 133 parts by weight

Modifier (dissolved epoxy resin) 6.65 parts by weight

Catalyst 0.075 parts by weight

Ethyl methyl ketone as needed

The cyanate ester / hydrocarbon resin / epoxy resin blend is available under the trade name Bakelite® EPS 05353 from Bakelite AG, Iserlohn-Lethmate. The modifier is available under the trade name Bakelite® EPM 05352 and the catalyst under the trade name Bakelite® EPC 05126 from Bakelite AG, Iserlohn-Lethmate.

The impregnated fabric is dried by a multi-stage vertical dryer at 160 ⁰ C air temperature and 188 ° C / 189 ° C radiant heater temperature to the required characteristics of the prepreg out.

The finished prepreg is characterized as follows:

Surface dry and smooth

Painting weight 350 - 360 g / m ²

Resin content prepreg based on 42-44% resin flow at 170 ⁰ C 20 + 2% Prepreg residual gel time at 170 C ⁰ 75 ± 25 sec

Prepreg powder viscosity at 135 ° C 15 + 5 Pas

Prepreg rape content <1, 0%

Example 3 Production of a Copper-Laminated Laminate

The laminate is made up of 8 layers of prepreg and 2 layers of 35 μm copper foil, one of which forms the topmost layer and the other the bottommost laminate layer. The curing takes place at a rate 2-4 K / min, a lamination temperature of at least 200 to 220 ⁰ C for 1 hour and an effective pressing pressure 10-50 bar.

The finished laminate is characterized as follows:

Surface smooth / even

Thickness incl. Cu 1, 60 ± 0.08 mm

Dielectric constant e _r (1 GHz) <3.8

Dielectric loss factor δ (1 GHz) <0.005

Copper adhesion 35 μm Cu foil> 1.30 N / mm

Interlaminar adhesion> 1.20 N / mm

Soldering test at 288 ° C> 180 sec

Pressure cooker test at 260 ⁰ C> 20 sec

T-260 test (TMA)> 60 min

T-288 test (TMA)> 10 min

Water absorption <0.20%

Flammability class V-O

Glass transition temperature T ₉ (DMTA):

1. Hardened at 200 ° C / 1 hr. 210 ⁰ C

2. Hardened at 220 ° C / 1 h. 230 ⁰ C

Claims

claims

1. Polymer material, in particular polymer mixture consisting of a mixture of at least one compatible with cyanate esters hydrocarbon resin, at least one cyanate ester and optionally at least one epoxy resin as polymer materials for the production of laminates for the printed circuit board industry.

2. Polymer material, in particular polymer mixture, according to claim 1, characterized in that the mixture of cyanate ester resin of the general

Formula I

R (OC≡N) _n

3. Polymer material according to claim 1 or 2, characterized in that the mixture as Cyanatesterharz at least one compound of the general formula II

having,

Z = -CN or, if appropriate, hydrogen X = a divalent organic radical, in particular a substituted or unsubstituted linear, cyclic or branched alkyl or benzyl radical having 1 to 10 carbon atoms, where X may be identical or different from one another, R = inert organic radical, in particular an alkyl, halogen, an ether or ester radical m = a number from 0 to 4 a = a number from 0 to 10.

4. Polymer material according to claim 3, characterized in that the mixture as the cyanate ester resin at least one compound of the general formula II with Z = -CN, X = methylene, where a = 0 to 5 may be.

5. Polymer material according to one of claims 1 to 4, characterized in that the mixture comprises as cyanate ester resin, a polyfunctional phenol cyanate / phenol triazine copolymer.

6. Polymer material according to one of claims 1 to 5, characterized in that the mixture has as a hydrocarbon resin at least one resin which is compatible with Cyanatesterharzen the general formula IR (OC≡N) _n , wherein R is a mononuclear or polynuclear aromatic or alkylaromatic substituted or unsubstituted radical and n is a number greater than 1 and is selected from the group of petroleum or petroleum resins, coal tar resins and terpene resins.

7. Polymer material according to claim 6, characterized in that the mixture have as hydrocarbon resin at least one resin which has been modified by copolymerization with phenol and / or styrene.

8. Polymer material according to one of claims 1 to 7, characterized in that the mixture comprises, as hydrocarbon resin, a combination of a phenol-modified petroleum-derived hydrocarbon resin with a liquid styrenated phenolic resin.

9. Polymer material according to claim 8, characterized in that the weight ratio of the combination of phenol-modified petroleum petroleum hydrocarbon and liquid styrenated phenolic resin in the range of 0.3 to 1, 7 to 1, 7 to 0.3.

10. Laminate for the printed circuit board industry, made of polymer material, in particular a polymer mixture, according to one of claims 1 to 9.

11. Use of a polymer material according to any one of claims 1 to 9 for the production of printed circuit boards and laminates for the printed circuit board industry.