DE2028747C3 - Process for the production of moldings from inorganic powders and epoxy resin - Google Patents

Description

as ceramic waste products, furthermore graphite, Re- After further mixing until it has cooled down

charcoal and similar substances can be used a compressible mass taken from the drum,

will. It is a free-flowing mass that is un-

It has been shown that the strength or the hardness can be processed indirectly after removal from the drum further molded parts according to the invention with a grain size of 5. The shaping can take place according to the pressing and extrusion-molding organic substances known in or the grain size distribution of the other ceramics used and the optionally used Ζυ- see process. As a result of their good trickle blows, the masses according to the invention are suitable for using grain size, which, in interaction with io, also for processing in automatic presses, for each composition of the ability and their excellent pressed grain intrinsic organic raw materials. The highest possible consolidation of the binder used is an advantage.
It can also be applied to the mouthpiece of a vacuum. In general, a grain size range of extrusion press or some other suitable press between 0.1 and 1 mm comes into consideration. Within the area used in each device, a metal mold with ventilation ducts, the widest possible spread, depending on the type of injection mold, is to be used and the grain size is advantageous. Press cold masses into these molds, the good ones

A further consolidation or increase in the hardness Slidability of the prepared according to the invention

is achieved when the relatively coarse material of the mass can be shaped without difficulty.

called grain size range 0.1 to 1 mm finest light. The nature of the masses makes a downtime in the

Material of the same basic material in amounts up to 20 Form as it has been used for similar compositions since then

50% is added, whereby the finest material had to be adhered to, superfluous.

Crushing and sieving to 75, 63 or 40μηη ge The masses described or the resulting from them

is won. Shaped bodies are made in several ways

A further increase in the quality of the molded parts can still be improved.

achieved by adding small amounts of pore-filling or lattice-removing or binding substances to the base material or the resin, namely substances from colloidal base material in the mixing drum or to the liquid daler fineness or substances similar to colloids, such as resin-hardener mixtures, can with the finished form silica, colloidal graphite or the like, but also SiO ₂ , have an extremely low water absorption. TiO ₂ or Al ₂ O ₃ , which are obtained from the vapor phase .

were, furthermore, substances that have a high proportion of micro- This can be achieved, for example, by silicon di-

like certain dolomite oxide from the vapor phase (hydrophilic »Aerosil«).

talke. From the latter comes a surcharge of up to 10 euros. Another improvement on the new one described

weight percent to the base batch in question, while masses can be achieved by adding the

the colloid-like additives up to 5 weight- 35 finished pellets - be it in the mixing drum

percent can be used (see example 1 to or in a separate appropriate process

11). direction - with a small amount of hydrophobic

Through a proportion of such additives, the hydrofluoric acid, z. B. one or more suitably

the ability of the mixture according to the invention so increased, chose aerosils or substances with a similar effect,

that the shape is also treated in the extrusion process in such a way that the mass grain is completely covered by one

can follow, with simultaneous deaeration of the mass, a very thin layer of these substances is enveloped. Here-

in a vacuum. By adding small amounts of the through, the flowability of the pressed grain becomes significant

Above-named highly dispersed substances to the new improved. In the case of the masses according to the invention

In addition, the notched impact strength of this process is offset by a new, surprisingly good one

finished molding increases. As a resin it is distributed.

As already mentioned, epoxy resin may be used, which is not inherent in the mixed color because otherwise the effect of the dye drum coming masses will be processed further immediately additives would be disturbed or reduced. so that storage is unnecessary. Should

The masses can also be lightfast in the mixer, however, once such is required, this may be the case organic or inorganic dyes, the former in the stored mass by the treatment described Quantities up to 0.5% can be added. treatment with hydrophobic silica or similar

In this case, a homogeneously thickened agent is obtained immediately again into a pressed grain of colored mass, from which colored shaped bodies of the highest quality are regenerated,
let put. The color can then be used in a similar way.After molding, the bodies can be used for color identification such as a suitable heating cabinet or in a decolorized glaze for conventional ceramic parts, speaking continuous furnace at temperatures up to, however, the maximum corresponding to the glazing 160 ⁰ C hardened. At this low tempe, operations are no longer necessary. the possibly added organic

The preparation of the mass is provided in such a way that dyes still have their full color effect,

taken that one first enables the 60 This low solidification temperature in a mixer

mineral component and possibly the accessories, together with the shaping of metal parts, armatures

hits of colloids and dyes in damp doors, solid semiconductors, magnetic bodies of all kinds,

mixed homogeneously in a condition-free state. Optionally molded parts made of carbon or graphite, electrical conductors

the mixer can be heated. ! In a heatable container or the like firmly in the molded body according to the invention

the resin is heated at the same time and embedded after 65.

A hardener is added in liquid form. After this process, composite bodies

Mix will be the homogeneous mixture of resin and be made. The characteristics of the new

Hardener sprayed into the running mixer drum. Moldings according to the invention are extreme in that

5 I 6

high proportion of inorganic filler has almost the following properties (cf. standard sheet DIN

finally through its specific properties 40 685):

true- accordingly, through suitable flexural strength 400kp / cm ²

Choice of inorganic anteUs also molded parts with notched impact strength 1.7 kp cm / cm *

higher dielectric constant, with a certain ohmic resistance to 5 leakage current Ka 3 c

see resistance or m ^: t intrinsic magnetic surface resistance [". '.'. 10» to 10 "Ω

shafts are made. Volume resistance ... ~ 10 ^{13 to ΙΟ 1} * Ω cm

The area of application of the moldings according to the density 2.0 kg / dm *

Invention is extremely versatile and is subject to temperature resistance. '. up to 200 ⁰ C practically no restrictions. Examples are the to

electrical insulation technology, parts for circuit 2. The following are mixed:

technology, magnetic and dielectric molded parts, calcite (0.1 to 0.8 mm grain size) 45

Potentiometer rings, parts for heat conduction and calcite (sieve material 10,000 meshes) ... 45

Thermal insulation young, etc. Epoxy resin 7.4

The economic and technical progress through the 15 hardeners 2.6

procedural measures according to the invention and form- 100.0

body is a significant one: to be admitted

By eliminating numerous work steps

the usual production method of technical ceramic dye - · - 0.3

parts results in a very economical manufacturing, and in 20 silica from the vapor phase .... 0,3 particular by reducing the manufacturing _{Miscnung This} has over that of the temperature to 160 ⁰ C (1200 ° C Example 1 größenordnungsmaßig improved flowability . The end of ceramics). By directly injecting f _{orn, en} and curing can be carried out as loud or through the fixed-joining of metal parts Example 1 and the final form of the body or other solid bodies with the shaped bodies after 25 _{wdsen then the} same strength and Widetder invention is equally another essential Verminde- _S tands data on how they are specified there, tion of operations given. A special feature of the new moldings is their extraordinary 3. There are mixed: high dimensional accuracy, which adheres to very small calcite (0.1 to 1 mm grain size) .. 40

Tolerances enabled, due to the elimination of 30 calcite (sieve material 6400 meshes) 40

any firing shrinkage. This means that soapstone 10

Ornate thin-walled moldings are produced, epoxy resin 7.4

without warping in the hardener 2.6 - as in ceramics

Brande and thus high rejects are feared 100.0

got to. This means a further increase in the host value

Harmfulness.

Furthermore, the moldings according to the invention have silica from the vapor phase,

compared to known parts made of plastics a hydrophobic 0.3

exceptionally high proportion of cheap inorganic

see components. In addition, there is the possibility of 40 On the shaped and then hardened cor-

production process known from ceramics, the following data were determined (see standard

to be used with a high number of pieces per unit of time. sheet DIN 40 685):

The economics of the new process will

further increased by the fact that characteristic flexural strength 395 kp / cm "

and / and processing-improving additives only in 45 notched impact strength 1.9 kp cm / cm *

small amounts are required. They are both tracking resistance ^Ka j3c

with the dye additives as well as with the use surface resistance 10 «U

of the hydrophobic aerosil below 0.5%. Volume resistance ~ 10 "Ω cm

The properties of the by means of the method according to density 2.0 kg / dm

Moldings produced according to the invention come with a temperature resistance of up to 200.degree

mechanical and electrical respect to those of a 4. The following are mixed:

Porcelain of the type KER 111 according to DIN 40 685 far- ' _{Kalkspat (0> 1 to} 0.9 mm grain size) 40

going near. Calcite (sieve material 6400 meshes) .... 40

_. . , Dolomittalkum (16,000 meshes,

^For P ^iele 55 alkali-free) 10

_. t _v j η · · 1 -jj-χί τ Epoxy resin 7.4

In the examples below, the compound hardeners are 2.6

compositions given in parts by weight.

1. Mix as described above: add

Calcite (0.1 to 1 mm grain size) .. 45 ° Highly dispersed silica 0.4

Calcite (sieve material 6400 meshes) 45

Epoxy resin 7.4 5. The following are mixed:

Hardener 2.6 calcite (0.1 to 1 mm grain size) .. 30

₁₀ QQ ₆ Kalkspat (sieve material 6400 meshes) 60

'' Epoxy resin 7.4

From this, moldings are created which directly hardener -2,6

subsequently hardened. You then have the 100.0

Admittedly

Silica from the vapor phase,
hydrophobic 0.6

6. The following are mixed:

Calcite (0.1 to 0.9 mm grain size) 30

Calcite (sieve material 6400 meshes) 50

Dolomittalkum (16,000 meshes) 13.25

Epoxy resin 5.0

Hardener 1.75

100.00 is added

Aluminum oxide from the vapor phase 0.5 highly disperse silica 0.5

7. The following are mixed:

Calcite (0.1 to 1 mm grain size) .. 30

Calcite (6400 mesh screenings) 60

Epoxy resin 7.4

Hardener 2.6

100.0 is added

Colloidal graphite 3.0

Silica from the vapor phase 0.5

8. The following are mixed:

Ferrites (0.1 to 1 mm grain size) 30

Ferrites (screenings 10,000 meshes) 60

Epoxy resin 7.4

Hardener 2.6

100.0 is added

Colloidal graphite 0.5

Silica from the vapor phase 0.7

9. The following are mixed:

Titanate (sieve material 6400 meshes) 60

Titanates (screenings, 10,000 meshes) ... 30

Epoxy resin "7.4

Hardener * 2.6

100.0 is added

Titanium dioxide from the vapor phase 0.5

10. The following are mixed:

Ferrites (0.1 to 0.2 mm grain size) .. 45

Ferrites (6400 mesh screenings) 45

Epoxy resin 7.4

Hardener 2.6

Admittedly
Carbonyl iron

11. The following are mixed:

Retort carbon (0.1 to 1 mm grain size)

Retort carbon (sieve material 6400 meshes)

Epoxy resin

² S hardener

100.0 1.0

45

45 7.4 2.6

Admittedly

Colloidal graphite

Silica from the vapor phase

100.0

1.0 0.3

The above bulk compositions are examples of the invention. The combinations of different substances can be varied as required in a meaningful way, depending on the intended use, which the new moldings are to serve. This is especially true for dielectrics and for shaped magnetic bodies, in which finer grains may have to predominate.

609682/13

Claims (6)

1 2 relevant substances fully apply, z. B. electrical claims: insulating properties, climate and heat resistant. ability, possibly also special dielectric or 1. Process for the production of shaped bodies with magnetic properties (e.g. titanate or ferrites), from a mixture of inorganic powders and 5 The ceramic working method brings compulsory epoxy resin, the mixture, if appropriate, also has certain disadvantages, including among others Embedding of mold body parts, deformed rem are conditioned by the duration and cost of the and a heat hardening with an increased temperature manufacturing process (in particular the sintering with temperature is subject to high temperatures) and the dimensional deviations that shows that the dry inorganic ausio is caused by the shrinkage during sintering gang powder that has a grain size with a very fine can. proportion not less than 0.04 mm and a rough portion Therefore, attempts have already been made does not exceed 1 mm, with a maximum of 10 Ge the substances in powder form by means of suitable organic weight percent epoxy resin and freshly added binder without sintering into molded parts, hardener sprayed and this mixture preferably - if necessary after heating at a moderate temperature, immediately afterwards by a press - temperatures only have those properties, possibly with the embedding of molds - which are necessary for the intended applications, body parts formed and preferably immediately - without the possible additional advantages bar after a curing at a maximum of 160 ⁰ C of the corresponding sintered materials,
is subjected. *> A practical example of this are the magnetic 2. The method according to claim 1, characterized in that see mass cores made of ferrite powders with binders records that as an inorganic substance mineral according to the German patent specification 756 383, p. 2, Calcite is used. Line 103 ff., Which are used to achieve magnetic effects 3. The method according to claim 1 or 2, thereby serving gene in high-frequency fields,
characterized that the inorganic substance in Colloidal graphite or from bodies has not found any practical use,
_{SiO 1} TiO ₂ obtained from the vapor phase and / or both of the above-mentioned processes are suitable A1, O "in amounts of up to 5% and optionally 30 namely only for the production of simply designed lightfast dyes in amounts of up to 0.5% beige molded parts, as they are as full cylinders, hollow cylinders or joins. Rings for ferrite cores or the like can be considered 4. The method according to any one of claims 1 to 3, men, but not for the production of molded parts characterized in that the raw batch entails a complicated shape, as is the case with the electrical are not required either in the mixing drum or after removing 35 insulating parts. is treated with colloid-like substances. The method according to the invention is a new the addition of substances does not exceed 1%. like working method for the production of molded parts 5. The method according to any one of claims 1 to 4, from inorganic powders without sintering, the characterized in that molded metal parts, described disadvantage of the restriction to molded fittings, electrical conductors and semiconductors, 4 ° parts are not subject to simple shapes and are non-magnetic Body of any kind, molded parts from the additional advantages brings with it the following Carbon or graphite, the properties of which are listed and explained by. The manufacturing process according to the invention is not the manufacturing process according to the invention can be changed in one operation in the already known mass marked by the association cold pressed in, whereby at Beaver with new, previously unknown process steps Use of automatic presses this with feeder and enables simple and economical Fertivorrichrungen for the solid bodies to be pressed in, the supply of molded parts from 90 and more weight samples are. cent inorganic powder, so with particularly low 6. The method according to any one of claims 1 to 5, proportions of organic binders, also with komditzt characterized in that body shapes placed on the mouthpiece 50. A crucial club suitable vacuum pressing or extrusion process is that the inorganic Set up metal molds with venting devices with components of the raw material in a mixing drum lines are placed so that in this a homogeneous mixture of a synthetic resin and Mass pressed in firmly and immediately cold-formed and sprayed with an associated hardener. Through this is, if necessary, incorporated into the molds, it is possible to obtain a raw mass which put metal fittings or other solid bodies from without the physical or otherwise for draining the pressed-in mass is at least partially press-closed for chemical processes will. forms and immediately after the shaping of a Curing at a maximum of 160 ⁰ C are subjected 60 can. Inorganic starting materials which have proven to be particularly suitable are those which are inherent in nature The subject of the present invention is a process or by previous ceramic or technical means for the production of molded parts from inorganic see processing have a crystalline structure. Such see powders and epoxy resin. Molded parts from such 6g substances are z. B. calcite, magnesite, natural or Materials are usually manufactured according to ceramic working synthetic ferrites, zircon sand, titanates and titanium. The sintered products bring dioxide, possibly after special manufacturing nhvsical and chemical characteristics of the process. Also silicates in mineral form or