JPS61102706A - Magnetic material to be treated and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve damp-proofing and dispersibility, and to ensure high quality by deionization washing-treating and lipophilic-treating the surfaces. CONSTITUTION:Magnetic material powder is deionized and treated, and lipophilic-treated. Magnetic material powder is charged into ion-exchanging water, agitated sufficiently, and separated from water through precipitation, centrifugal filtration, etc. Such pre-washing is executed, and a magnetic materials is deionized and treated. There are a cation exchange resin and an anion exchange resin in ion exchange resins, and the magnetic material to be deionized and treated is further lipophilic-treated. Accordingly, the surfaces are deionization washing-treated and lipophilic-treated, impurity ions which give hygroscopicity and weaken bonding power among the surfaces of the magnetic material and the resins are removed, and affinity with the resins is improved owing to lipophilic treatment, thus acquiring a magnetic toner, magnetic ink, magnetic paints, a magnetic tape, etc., damp-proofing and dispersibility thereof are enhanced and which have high quality.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a powdery magnetic material used in magnetic toner, magnetic ink, magnetic paint, magnetic tape, etc., and a method for producing the same.

[Prior Art] Conventionally, various magnetic powders have been used in magnetic toner, magnetic ink, magnetic paint, magnetic tape, and the like.

A representative example of this is 1, for example Fe30. or γ-Fe207
is synthesized from various starting materials. For example, in the case of acicular γ-Fe207, which is widely used as a magnetic material, a-Fe00H (Goethite) acicular crystals are dehydrated and reduced in a hydrogen stream to form Fe30Q. , is often produced by oxidizing it in air at a low temperature.

Iron ions F, 2+, Fe in these reaction processes
The reaction between 3+ solution etc. and alkaline solution is Fe (O
H) 2 and Fe (OH) 3 are produced, but these reactions are extremely complex when oxygen is dissolved, and there are still many points that are unclear about this type of reaction.

The raw material mentioned above, Goethite, is used in paints with yellow iron oxide (
Mars yellow) is widely used as a pigment (orange-yellow to yellow), and is produced by causing a seed reaction between an aqueous FaSOa solution and an aqueous NaOH solution in the presence of air to form α-Fe20. -H2
The usual manufacturing method is to first generate microcrystals of 0.0, then add an iron piece and an aqueous FeSO4 solution, carry out the main reaction while blowing air, wash with water, and then dry.

By the way, regarding the route for obtaining the raw material Fe5Oa, in Japan, a large amount of ferrous sulfate is currently produced as a by-product from Bickling waste liquid or titanium white manufacturing waste liquid, and this V
By appropriately combining reaction conditions from a tfftm-iron solution, the above-mentioned Goethite and black Fe30p iron oxide particles can be obtained.

The magnetic powder particles obtained through such a complicated route are
Various ions such as Na'', Mn'' are present on its surface.
, Cr'◆, Cr", Ni", Go"
, SO42-.

OH-, NO3-, 0-, Br-, and I- remain and are not completely removed by normal industrial cleaning.

The presence of such impurity ions tends to impede the purpose of obtaining high-quality and stable magnetic toner or magnetic tape.

For example, due to the presence of Ha 2 SO 4'', the surface of the magnetic powder tends to absorb moisture, which tends to deteriorate the quality of magnetic toner and magnetic tape products.

In addition, magnetic materials are used dispersed in a resin called a binder, and the presence of surface impurities tends to weaken the bonding force with the resin, resulting in the achievement and maintenance of a stable dispersion state. Therefore, it is easy to cause deterioration in quality.

[Problems to be solved by the invention] In the present invention, impurity ions on the surface are removed, and
This was done in order to provide powder-like treated magnetic material whose surface has been treated to make it oleophilic and which can be used to produce high-quality magnetic toners, magnetic inks, magnetic paints, magnetic tapes, etc., with improved moisture resistance and dispersibility. be.

[Means and effects for solving the problems] According to the present invention, (1) a powder-like treated magnetic material whose surface is subjected to a deionization cleaning treatment and a lipophilic treatment; ) A powdery magnetic substance containing impurity ions is dispersed in water together with a cation exchange resin and an anion exchange resin, and after stirring, the water and ion exchange resin are separated, and dried AVK,
A method for producing a treated magnetic material is provided, which comprises reacting the surface of the obtained magnetic material with a lipophilic coupling agent.

The present invention is constructed by subjecting the obtained magnetic powder to deionization treatment and then further lipophilization treatment.

In other words, deionization treatment involves putting magnetic powder into ion-exchanged water, thoroughly stirring it, separating it from the water by sedimentation, centrifugation, filtration, etc., performing pre-cleaning in this way, and then deionization treatment. It is preferable to carry out the deionization treatment by exchanging cations in ion-exchanged water or pure water. ! ! ! Add the magnetic powder together with the resin and anion exchange resin, stir thoroughly,
Next, water and ion exchange resin are separated, and this operation is repeated an appropriate number of times, followed by drying.

Ion exchange resins used in the present invention include cation exchange resins and anion exchange resins.
"Diaion" etc.

The lipophilic coupling agents used in the present invention include "Fuorenact J
TTS, 9S, 38S, 418. 46B,
There are varieties such as 55°1388 and 2388, and there is also A-1 (TP
T), B-1 (TOT), TOT, TST, T
AA, TAT, TLA, (Ti eclipse C).

Ding OG, TBSTA, A-10・(TPT polymer), B-2, B-4゜B-7, B-10 (more than TB
T polymer), TBSTA-400 (TBSTA polymer), TTS, TOA-30, TSDMA, T
T.A.B.

Examples include TTOP, and commercially available silane coupling agents can also be used.

Any commercially available magnetic material can be used as the magnetic material used in the present invention, such as rMAT 120 JrMAT manufactured by Toda Kogyo.
210 J rEPT 500 J rMAT
115 J rEPTloooJ, rMG-W manufactured by Mitsui Kinzoku Kogyo, Tokyo Denki Kagaku Kogyo type rcAP-I
JrcAP-2J etc. can all be used.

[Example] Next, the present invention will be explained with reference to Examples.

Example 1 Toda Kogyo rMAT 210 J 10k as magnetic material
g was added to 50 g of ion-exchanged water (electrical conductivity: 0.2μ5) and stirred for 20 minutes. The conductivity of this supernatant liquid was 85 μs.Next, the supernatant liquid was removed, and the above ion-exchanged water was added and stirred in the same manner. Therefore, the primary apparent amount is 32
"Diaion SA 10AJ (manufactured by Mitsubishi Chemical Industries) and "Diaion 5KIBJ (manufactured by Mitsubishi Chemical Industries, Ltd.)"
When the mixture was mixed with M) and stirred for 60 minutes, the elution conductivity was 8 gS. The deionized magnetic material was separated and then dried to obtain a deionized magnetic material.

This deionized magnetic material was further subjected to lipophilic treatment. 3 kg of dry deionized magnetic material
45 g was added and sufficiently stirred with a mixer to remove the isopropyl alcohol produced.

For 60 parts by weight of the magnetic material of the present invention treated in this way,
Polystyrene: Pico-Stick D-125 (Enso Standard Oil) 90ffif 1 part Polypropylene:
860P (Sanyo Kasei) 10 parts by weight was blended and kneaded for 1 hour at 150°C with a hot roll mill, cooled, coarsely ground with a cutter mill, and then finely ground with a jet mill to produce toner of 1 to 30 parts. Fine particles were obtained.

Using a wind classifier to separate the above toner into particles of 5 to 20 tiles? '
), the volume average particle diameter at that time was 14 pm.

A one-component magnetic toner prepared using the above-mentioned treated magnetic material of the present invention was compared with toner prepared using an untreated magnetic material and a magnetic material subjected to only deionization treatment.

Good particle size was obtained in the present invention and the deionized product, but on the other hand, in the untreated product, the particle size was coarse, and the volume average diameter was adjusted to t4g soda by classification.

Furthermore, for comparison, the moisture absorption rate of the toner was measured.

The moisture absorption rate was determined by increasing the weight of the toner sealed in a desiccator with water at 25°C, and it was 0.2% in 24 hours for the toner made of treated magnetic material.
It was 0.3% for toner made of magnetic material that was only deionized, and 0.6% for untreated toner.

Furthermore, the moisture resistance of the toner was compared by conducting an actual firing durability test using a copying machine. Canon electrophotographic copying machine PC-
20 was tested at a high temperature and high humidity of 35℃ and 85% RH, and the durability was 2,000 sheets.
The maximum image density on the sheet decreased to 0.35 with the toner made of untreated magnetic material and to 0.55 with the toner made with deionized magnetic material, whereas The toner maintained a high value of 0.85.

[Effects of the Invention] As described above, the surface of the magnetic body of the present invention has been subjected to deionization cleaning treatment and lipophilization treatment, and the impurity ions that impart hygroscopicity and weaken the bonding force between the magnetic body surface and the resin are removed. This is a high-quality magnetic toner with improved moisture resistance and dispersibility, as it has been treated to be lipophilic and has good affinity with resin.
magnetic ink.

Magnetic w p+ , magnetic tape, etc. can be provided. Further, in the manufacturing method of the present invention, a treated magnetic material having excellent physical properties as described above can be easily obtained.

Claims (2)

[Claims] (1) A powder-like treated magnetic material whose surface has been subjected to deionization cleaning treatment and lipophilic treatment. (2) A powdery magnetic material containing impurity ions is dispersed in water together with a cation exchange resin and an anion exchange resin, and after stirring, the water and ion exchange resin are separated, and after drying, the obtained magnetic material is A method for producing a treated magnetic material, characterized by reacting a lipophilic coupling agent on the surface.