DD301287A7 - Class 2 ceramic dielectrics according to IEC (Solution 4) - Google Patents

Abstract

The invention relates to dielectrics for capacitors, in particular for multilayer and disk capacitors, and active substances for printed capacitors. According to the invention, ceramic materials of technically pure raw materials based on separately preformed components give Ba in m TiO ind 3 (Pb ind x Sr ind 1 x) ind n ((Mg in 1/3 Nb in 2/3) ind y Ti ind 1- y) O ind 3 (Pb ind z A ind 1- z) ind l (v ind 1 B ind 1 ... v ind i B ind i) O ind 3 and (Pb ind t D ind 1- t) ind p (Ti ind q Zr ind s (u ind 1 C ind 1 .. u ind j C ind j) ind 1-qs) O ind 3 and eutectic mixtures of lead oxide and the oxides of W, Sb, Nb, Ta , Cu, Cr, Mg, Mn, Zn, Fe, Sn, Co, La, Pr, Ce, Didym or Bi or of Co and Mn or of Bi and Zn at different sintering temperatures and Curie points of the preformed components, taking into account those for A , B, C and D usable elements and the in the description of the invention by l, m, n, p, q, s, t, u, v, x, y and z specified molar proportions and adhering to the stated proportions by weight of these components and preservation of Polyphase in the sintered material suitable board Class 2 R1 ktrika according to IEC with dielectric constant epsilon ind r> = 3 000.

Description

Field of application of the invention

The invention relates to the field of electrical engineering / electronics and relates to ceramic dielectrics for capacitors, in particular for multilayer and disk capacitors, and active substances for printed capacitors.

Characteristic of the known state of the art

Miniaturization of the capacitors and improvement of the material economy and labor productivity in the manufacture of these capacitors require an increase in the dielectric constant e, the effective dielectric while maintaining the lowest possible temperature dependence thereof, z. B. of max. ± 15% in the temperature range -55 ° C to + 125 ° C for class 2R1 according to IEC or X7R according to EIA standard.

It is generally known that the increase of the ε, by the use of ferroelectric ^ materials such. As BaTiO ₃ or mixed crystals, is reached, with increasing e, increasing dependencies of the same must be accepted by the temperature, and that surcharges to lower the sintering temperature T "in the conventional ceramic multilayer capacitors, especially to reduce the proportions of high-melting expensive precious metals Pd, Pt or Au can lead into lying between the dielectrically active layers electrode layers, the ε, lower.

In compliance with the temperature characteristics of class 2R1 and a sintering temperature T ₁ below 1140 ⁰ C, the solution according to DD-PS 258915 represents a technologically manageable and reproducible solution. With their compositions based on BdTiO ₃ and mixtures of bismuth layer compounds and other additives, however only ε, values reached around 2000.

Other known solutions, such as DD-PS 140871, DD-PS 268002, DE-OS 2923981, US-PS 3619220, DE-AS 1640168 and US-PS 3619744 reach the state of the solution according to DD-PS 258915 not by either lower ε, values result and / or the class 2R1 not enough.

Also known is a solution consisting of 2 components of BaTiO ₃ , of which at least 50% of the mass fraction used must be in the particle size range of 0.7 to 3.0 μm, and a complex lead piperite kit according to EP 257653.

However, the dielectrics corresponding to this solution, which satisfy class 2R1, only achieve ε, values of max. 2920 at

Sintering temperatures T "which are not lower than 1200 ° C. ₍

Another solution which, according to EP 205137, yields ε, values of 3205, while maintaining the temperature characteristic of class 2R1 in the most favorable case. In this case, one with Nb ₂ O ₆ or Ta ₂ O ₆ and Sm ₂ O ₃ or other oxides of the SE Elements of atomic numbers 57 to 62 added BaTiO ₃ and further separately supplied dopants of a mixture of MnO ₂ and NiO used.

Significant disadvantage of this solution containing a SintertemperaturT from 123o ⁰ requires C, and all the solutions according to EP 205137 A2 are the high demands on the main component of BaTiO. ₃

The high ε, values are achieved only when using a high-purity, very fine BaTiO ₃ : The solution requires particle sizes of <1 pm and total impurities of SiO ₂ , Al ₂ O ₃ and Fe ₂ O ₃ of less than 0.2 parts by mass in %. In the case of the usual large-scale production of BaTiO ₃ , this can only be achieved by using analytically pure, expensive raw materials and special, expensive grinding media. Furthermore, these materials are very sensitive to sintering. Even with minor deviations from the optimum sintering temperature, the temperature characteristic of class X7R is no longer complied with. In addition, gigantic grain growth occurs, which precludes use in ceramic multilayer capacitors in which sintered effective dielectric layers with thicknesses from 25 μm are already realized today.

Object of the invention

The aim of the invention is to find material compositions which, when using industrially produced BaTiO ₃ , enable a reproducible production and advantageous technical data in the case of ceramic dielectrics of class 2 according to IEC compared with the prior art.

Explanation of the practice of the invention

The invention has for its object to find compositions which, when using BaTiCb with a particle size d _M s3,5pm and a purity of 2: 0.98 parts by mass and other at least technically pure raw materials, including Soltenerden or mixtures thereof, at sintering temperatures T ₁ 1200 ° C and a possible sintering interval of at least 3OK ceramic dielectrics with dielectric constant ε, £ 3000 class 2R1 according to IEC revealed that also for use in ceramic multilayer capacitors with thicknesses of the sintered, dielectrically active layers & 25 μιτ. are suitable. According to the invention, this object is achieved by compositions of at least the three components K1, K2 and K4 of the preformed and subsequently defined components K1 to K4 and an addition of an oxidic eutectic E:

K 1 = Ba _1n TiO ₃

or Ba _1n TiO ₃ with up to 0.03 mass parts of the usual dopants, where im = 0.97 ... 1.00,

K 2 = (Pb »Sr, _,)" [{Mg, _n Nb "j) _y Ti, _ _v ] 0j

with χ = 0.75 ... 0.98 y "0.70 ... 0.95

and η = 0.98 ... 1.06, which at a sintering temperature of between 1150 and 125O ⁰ C ⁰ C dichtsintert and at 25 ⁰ C a dielectric constant ε, has> 4000,

K3 = (Pb ₁ A ₁ -IMViB ₁

of which at least 0.6, and a maximum of 0.95 mole fractions PDi [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ with A = Sr, Ca, Ba,

B, ... Bi & Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ , Co ²⁺ , Mn ²⁺ , Fe ³⁺ , Co ³⁺ , Mn ³⁺ , Sc ³ S Ti ⁴⁺ , Zr ⁴ \ Sn ⁴⁺ , Hf ⁴⁺ , Nb ⁶⁺ , Ta ⁶⁺ , Sb ⁶⁺ , W ⁶⁺ , where V ₁ ... Vi denote the corresponding mole fractions of Bi ... Bi that satisfy the Smolensky conditions For

j i

Perowskite £ vi = 1 and £ wjV | <= 4, 1

ζ = 0.80 ... 1.0 and i = 0.98 ... 1.06, the sintered at a sintering temperature between 93O ⁰ C and 1060X and thereby in the temperature range of -20 ⁰ C to +60 ⁰ C in a maximum has a dielectric constant ε,> 8000, and

K4 = (Pb ₁ D ₁ -OpITi ₁₁ ZMu ₁ C ₁ ... U ₁ C ₁ ), - _q -.] O ₃

with D & Sr, Ba, Ca, SE or Didym, C, ... Cj £ Selection as under B ₁ ... B ₁ , where U ₁ ... Uj the corresponding molar amounts of C ₁₁₁₁ C) and Wi ".Wjdie corresponding valences of C ₁₁₁₁ Cj mean that the Smolensky conditions for perovskites

j i

q + s + £ uj = 1 and4 (q + s) + Ew ₁ Uj = 4, 1

with q = 0.40 ... 0.60, s = 0.30 ... 0.55 and q + s> 0.80,

t = 0.80 ... 1.00 for D & Sr, Ca, Ba, or t = 0.93 ... 1,00fürDASEoderDidym and ρ = 0.98 ... 1.06, which at a sintering temperature 1150 ⁰ C Dichtsinterert whose dielectric constant ε, at 25 ° C> 2 300, has a maximum at> 15O ⁰ C and after negative temperatures slowly decreases, and E is 5 PbO WO ₃ or another eutectic mixture of lead oxide and the oxides of Sb , Nb, Ta, Cu, Cr, Mg, Mn, Zn, Fe, Sn, Co, La, Pr, Ce, Didym or Bi or from the oxides of Co and Mn or Bi with Zn. These oxidic eutectics are by calcination at a temperature in the range of 500 ⁰ C to 950 ° C, but at least 3OK preformed below the respective eutectic point.

The proportions by mass of the four preformed and comminuted components K1 to K4 and the addition of oxidic eutectics in known manner are:

K1 = 0.30 ... 0.67 parts by mass K2 = 0.10 ... 0.55 parts by mass

K4 = 0.05 ... 0.25 parts by mass and K3 + E = 0.002 ... 0.20 parts by mass

with E between 0.002 and 0.03 parts by weight,

where the indication of the price of the addition is K K = 1.0.

Addition of the additive E takes place during the last mixing operation of the preformed and comminuted components. Depending on the composition of the dense sintering of geformton from this mixture in a known manner the body at a sintering temperature T can be in the range of 115o C and ⁰ 1200 ⁰ C take place.

In compliance with all other requirements for a capacitor material class 2 according to IEC, the dielectric constant ε, reaches at 25 ⁰ C values of at least 3000, with their change in the operating temperature range of -55 ° C to + 125 ° C does not exceed ± 15% and thus the Class 2R1 corresponds. Exceeding or falling short of the stated limits for the mass fractions of the four components and the addition of oxidic eutectics have the following effects:

In the case of the component K1, they lead to: u no longer flat temperature profile of the ε ,. In addition, when exceeding the rises

required sintering temperature to well above 1200 ⁰ C. If the proportion K2 is exceeded, the ε, which is still high at low temperatures, falls too steeply after higher temperatures.

Underruns of the proportion lead at negative temperatures to eino.n ε, -Abfall of more than 15%.

If the claimed component of component K3 is exceeded, the dielectric losses rise to higher temperatures, the insulation resistance drops below values of 1Ο '° Ω. The claimed fraction facilitates dense sintering without an ε, -fall.

Increasing the proportion of the component K4, the permissible for the class 2R1 maximalo ε, -Slope of 15% at -55 ⁰ C and can not be complied with, at the upper limit of the temperature Turbo Reich, at +125 ⁰ C, which allowed ε is , Waste not exhausted. Accordingly, if the proportion for K4 falls below +125 ⁰ C, it can lead to a strong ε, -Abfall.

If the proportion of E is exceeded, a higher sintering temperature T, is required, if loss factor increases and insulation resistance reductions should not be tolerated. Exceeding decreases the ε, while increasing the dielectric losses.

embodiments

The invention will be explained in more detail below with reference to 8 exemplary embodiments in the form of two tables and the description of the process steps for producing the individual components K1 to K4, of the additive E and of the total material which are known in principle, identical in all exemplary embodiments, with reference to the composition according to embodiment 1.

Table 1 indicates the composition and applied sintering regime, characterized by sintering temperature T ₁ and holding time.

Table 2 shows the obtained technical characteristics of the selected specimen forms.

The starting point of the synthesis is the preparation of the four components and the addition of oxidic eutectics.

Component K1: BaTiO ₃

The component K1 is formed in a known manner from equal molar proportions BaCO ₃ and TiO ₂ in a two-hour solid state reaction at 1200 ⁰ C. A fine grinding in drum or vibratory mills follows. TiO ₂ excess of up to 0.03 mole fractions is not critical.

Component K2: (Pbo.e8Sro, i2) t (Mgi / ₃ Nb _2/3) o, 8TiO, _2] 0 ₃

First, MgNb ₂ O _{6 is} preformed from MgCO ₃ and Nb ₂ O ₆ by a three-hour solid-state reaction at 1100 ° C. An excess of 0.04 molar amounts of Mg in the offset is not only uncritical, but even favorable.

The preformed MgNb ₂ Oe is admixed with PbO or Pb ₃ O ₄ , SrCO ₃ and TiO ₂ according to the molar proportions given by the formula and this mixture is calcined at 1100 ° C / ₂ h. The product is then reduced to a grain size

d _M £ 5μΓΠ finely ground. An excess of up to 0.06 molar amounts of PbO or Pb ₃ O _{4 is} permitted.

The sintered at 1175 ° C / 2h component K2 has as a single component an ε,> 5000 at 25 ⁰ C. The ε, maximum, which is about 5O ⁰ C, has values of> 8000. The structure is perovskite with a low proportion of a pyrochlore residue phase.

Higher annealing of the component K2 is possible, but not advantageous, since the subsequent comminution is made more difficult and the required sintering temperature T _{1 of} the total material increases.

Component K3: Pbo

The preparation is carried out by direct synthesis from the raw materials Pb ₃ O ₄ or PbO, SrCO ₃ , Fe ₂ O ₃ , Nb ₂ O ₆ , WO ₃ , NiO and SnO ₂ , which are mixed according to the molar proportions given by the formula and at 800 ° C. / 2 h burned up. The subsequent fine grinding took place for 6 hours in an agate powdered iron. A shortening of the grinding time is possible, but d _M should be <Bumsein.

An excess of up to 0.06 Mengenmengenanteilei, PbO or PbjO ₄ is not critical.

As a single component, the material used here as component K3 on disk-shaped test specimens, which at 1020 ° C./2 hours of internal density, has the following values:

ε, at 25 ⁰ C «17000 ε, maximum at 29 ⁰ C.

Similar values are achieved when two subcomponents, one from the raw materials Pb ₃ O ₄ or PbO, Nb ₂ O ₆ and WO ₃ at 700 ° C / 2 h and the second from the remaining raw materials at 1000 ° C / 2 h, are preformed separately and the further treatment of the component K3 takes place with the proportions given by the formula.

Component K4: PblZr _0, 4eTio, <e (Ni | / 3Sb _2/3) o oel03

The preparation is carried out by direct synthesis from the raw materials Pb ₃ O ₄ or PbO, ZrO ₂ , TiO ₂ , NiO and Sb ₂ O ₃ by these are mixed according to the dürr 'ι the formula given molar proportions and the mixture of a solid state reaction at 85O ⁰ C. to 900 ° C with 2h holding time is subjected. It is followed by a fine comminution to a particle size of dso S 5μιη, for which in this case a 3-hour treatment in a Achatpulverisette sufficient.

The at 1280 ° C / 2h dichtsinternde component K4 as a single component at 25 ⁰ C has an ε of 2 500. The ε, -Maximum is about 280 ⁰ C.

Additions:

The Eutektika 5 PbO · Nb ₂ O ₆ , 5 PbO · Co ₂ O ₃ , 5 PbO · Sb ₂ O ₃ , 6 PbO · ZnO, 5 PbO Nd ₂ O ₃ , 5 PbO · NiO are prepared by direct synthesis from the raw materials PbO, Nb ₂ O ₆ , Co ₂ O ₃ , Sb ₂ O ₃ , ZnO, Nd ₂ O ₃ , NiO. The raw materials are mixed in the appropriate molar proportions and subjected to a holding time of 2 h of a solid-state reaction. The preforming temperatures are:

5PbO-Nb ₂ O ₆ 700 ⁰ C. 5PbO-Co ₂ O ₃ 700 ⁰ C. 5PbO-Sb ₂ O ₃ 600 ⁰ C. 6PbO ZnO 700 ° C 5PbO-Nd ₂ O ₃ 85O ⁰ C 5 PbO NiO 900 ⁰ C

The preparation of the Gesamttwerkstoffo of the embodiments of the invention takes place by the so or prepared in principle the same way components K1 to K4 mixed with the addition E of oxidic eutectics in the proportions shown in Table 1 and advantageously again burned at 1000 to 1050 ° C / 2h and be finely ground. This repeated homogenization and fine grinding, which serves for improved homogenization, can also be omitted. Common intermediate treatments of several preformed components are also possible. The addition of the additive E always takes place during the last mixing process of all the components involved.

The further processing of the powdered material according to the invention is carried out in a known manner by the product-specific shaping after prior plasticization and possibly further required process steps, such as metallization for multilayer capacitors, and sintering.

The holding time of the specimens of the embodiments was always 2 h.

Table 1 Composition and mass fractions of the components

Execution Ex.

Component 1

Component 2

Component 3

Proportions of substance

Component 4

T. CC)

BaTiO ₃

40%

30%

Pb [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ 86 Pb [Fe ₂ Z ₃ W _1n ] O ₃ 6 Pb [Ni _1n Nb _2n ] O ₃ 5 SrSnO ₃ 3 + 1Ma .-% Pb0 20%

Pb [Zr ₀₁₄₈ Ti _0-4

5PbO-Nb ₂ O ₅ 1170

+ 1.5%

2 BaTiO ₃ 40% (Pb ₀ J ₀ Sr ₀₁₂₀ ) [Mg _1n Nb _2n ) O ₁₈ Ti ₀₁₂ ] O ₃ 30% Pb [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ Pb [Fe ₂ Z ₃ W _1n ] O ₃ 15% 65 35 Pb [Zr _0-46 Ti _0l46 (Ni _1n Nb _2n ) O _-08 ] O ₃ 15% 5PbO-Co ₂ Os + 1.0% 1180 3 BaTiO ₃ 55% 26% Pb [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ Pb [Fe _2n W ₁ Z ₃ ] O ₃ Pb [Zn _1n Nb _2n ] O ₃ 9% 60 30 10 (Mg _1n Nb ₂ Z ₃ ) O ₁₁₀ ] O ₃ .10% 5PbO-Sb ₂ O ₅ + 3.0% 1160 4 BaTiO ₃ 40% (Pb ₀ JoSrO ₁₂₀ ) [Mg _1n Nb _2n UTi ₀₁₂ ] O ₃ 30% Pb [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ Pb [Fe ₂ Z ₃ W ₁ Z ₃ ] O ₃ 15% 65 35 Pb [Zr _0i46 Ti _0-46 (Ni _1n Nb _2n ) O ₁₀₈ ] O ₃ 15% 5PbO-ZnO + 2.0% 1160 5 BaTiO ₃ 40% 30% Pb [Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ Pb [Fe _2n W _1n ] O ₃ 15% 65 35 Pb [Zr ₀₁₄₆ TiO ₁₄₆ (Ni _1n Nb _2n ) O ₁₀₈ ] O ₃ 15% 5PbO-ZnO + 0.5% 1170 6 like 4 like 4 like 4 like 4 like 4 5PbO-Nd ₂ O ₃ + 2.0% 1160 7 BaTiO ₃ . 66.3% 25.5% Pb [Zr _0i46 Ti _0i46 (Ni _1n Sb _2n ) O ₁ O ₈ ] O ₃ 8.2% 5PbO-NiO + 2.0% 1180 8th BaTiO ₃ 35.7% (Pb ₀ J ₈ Sr ₀₁₁₂ ) [Mg _1n Nb ₂ Z ₃ ) OjTi _0-2 ] O ₃ 40.8% Pb [Zr _0i48 Ti ₀₄₆ (Ni _1n Sb ₂ Z ₃ ) O ₁ O ₈ ] O ₃ 23.5% 5PbO-Nb ₂ O ₅ + 2.0% 1160

table

Ausführungsbelsp.

design

1 measuring frequency: 1 kHz.

2 measured at 25 ^° C.

3 based on 25 ° C.

4 statement for R ₁ , · C.

e,

tanö ¹¹ · "(ΙΟ" ³ )

lsulationswiderstand Rl ²¹ IO) or Ri.-C ⁴¹ Is)

^Λε '

in% ³¹

Max. Deviation in the range of

-55 ⁰ C to +25 ⁰ C to

+25 ⁰ C '+125 ⁰ C

1a disc 4200 18 > 10 " -14 ± 8 1b Multilayer cond. 3950 20 > 1 OOO ⁴¹ -15 ± 10 2 disc 4000 16 > 10 ¹¹ -15 + 10 - 5 3 disc 3750 17 > 10 " -13 + 5 -10 4 disc 3900 15 > 10 " -13 + 8 - β 5 disc 3900 16 > 8 · 10 ¹⁰ -15 +10 - 5 β disc 4100 18 > 10 " -12 ± 6 7 disc 3400 11 > 5 x 10 " + 5 -13 ± 10 8th disc 3500 11 > 5O0 ¹² + 8-12 ± 9

Claims (4)

1. Class 2 ceramic dielectrics according to IEC on the basis of five different components essentially known in their basic composition, barium titanate, at least two out of three complex lead pervalskites and an addition of oxidic eutectics, characterized in that of the separately preformed components K1 to K4 have at least two different sintering temperatures, have at least two different Curie temperatures and that the components are in the range of the following composition: K 1 = Ba _1n TiO ₃ r ^{: t} m = 0.97 to 1.00, wherein the barium titanate may also contain up to 3 parts by mass in% of the usual dosages, K 2 = (Pb _x Sr ₁ -XU (MWD ₃ Nb ₂ Z ₃ VTi ₁ _ _y] O ₃ with χ = 0.75 ... 0.98 y = 0.70 ... 0.95 and η = 0.98 ... 1.06, of which at least 0.60, but max. 0.95 mole fractions Pb ^ Fe ₁ Z ₂ Nb ₁ Z ₂ ] O ₃ with A ^ Sr, Ca, Ba, B ₁ ... Bj ^ Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ , Co ²⁺ , Mn ²⁺ , Fe ³⁺ , Co ³⁺ , Mn ³⁺ , Sc ³ Mi ⁴⁺ , Zr ⁴⁺ , Sn ⁴⁺ , Hf ⁴⁺ , Nb ⁸⁺ , Ta ⁵⁺ , Sb ⁵⁺ , W ⁶⁺ , i i where £ Vj = 1 and £ wjV | = 4 must be if V ₁₁₁₁ Vi the corresponding 1 1 Substance proportions of B, ... Bj and W ₁ ... Wj denote the respective valences of these B ₁ ... Bj, ζ = 0.80 ... 1.0 and / = 0.98 ... 1.06, K 4 = (Pb ₁ D ₁ _, Jp (TIqZr ₈ (U ₁ C ₁ ... UjCj) ₁ _ _q _ _e ] O ₃ with D δ Sr, Ba, Ca, SE or Didym, C ₁ ... C ₁ & Mg ²⁺ , Ni ²⁺ , Zn ²⁺ , Fe ²⁺ , Co ²⁺ , Mn ²⁺ , Fe ³⁺ , Co ³⁺ , Mn ³⁺ , Sc ³⁺ , Ti ⁴⁺ , Zr ⁴⁺ , Sn ⁴⁺ , Hf ⁴⁺ , Nb ⁵⁺ , Ta ⁵⁺ , Sb ⁶⁺ , W ⁶⁺ , where q + s + £ uj = 1 and 4 (q + s) + LWjUj = 4, if U ₁ ... Ujdie corresponding molar amounts of C ₁ ... Cj and W ₁ ..Wj denote the respective valences of these C ₁ ... Cj, q = 0.40. ..0,60 s = 0,30 ... 0,55, where q + s> 0,80 t "= 0,80 ... 1,00for D £ Sr, Ca, Ba t = 0.93 to 1.00 for D ^ SE or Didym and p = 0.98 to 1.06, and E is a eutectic mixture of lead oxide and the oxides of W, Sb, Nb, Ta, Cu, Cr, Mg , Mn, Zn, Fe, Sn, Co, La, Pr, Ce, Didym or Bi or from the oxides of Co and Mn or Bi and Zn,
the one max. have eutectic point <98O ⁰ C, that they are in the mass fractions K1 = 0.30. ..0.67 K2 = ^ 0.10 ... 0.55 K4 = 0.05. ..0,25 4 and K3 + E = 0.002 ... 0.20 with E = 0.002 ... 0.03 relative to £ K = 1 in the offset of respective ceramic dielectric are contained, and that the sintered material according to the components is multi-phase. 2. Ceramic dielectrics according to claim 1, characterized in that the component K2 preferably at 25 ⁰ C has a dielectric constant ε,> 4000 and between 115O ⁰ C and 125O ⁰ C dense sintered. 3. Ceramic dielectrics according to claim 1 or 2, characterized in that the component K3 preferably between 93O ⁰ C and 1060 ⁰ C dense sintered and between -2O ⁰ C and + 60 ⁰ C has an ε, maximum> 8000. 4. Ceramic dielectrics according to claim 1,2 or 3, characterized in that the component K4 preferably at a sintering temperature> 115O ⁰ C dense sintered, at 25 ⁰ C has an ε,> 2300 and at> 15O ⁰ C an e _r maximum having.