JPS60106861A - Inorganic powder modified with organic phosphate compound - Google Patents

Abstract

PURPOSE:To provide an inorg. powder having good dispersibility and fillability in paints or resins, by coating the surface of the powder with a specified org. phosphate compd. CONSTITUTION:An org. phosphate compd. of formula I or II [wherein R, R' are each a 1-30C aliph. org. group, alicyclic org. group (which may be unsaturated or satd.); n is 2-3; m is 1-10] such as an ethylene oxide adduct of lauryl phosphate is used. An inorg. powder such as silica, dolomite or ferrite is suspended in at lease an equal volume of water or an alcohol. While vigorously stirring the mixture, 0.2-10wt% (based on the weight of inorg. powder) said compd. is added thereto. The solid component (cake) is recovered by filtration, dried and crushed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel inorganic powder surface-modified with an organic phosphate compound, and is applicable to rubber, plastics, conductive paints, conductive media, magnetic media, and magnetic recording media. The purpose is to develop inorganic powders useful for such applications as conventional synthetic resins. It is widely used for imparting flammability and other purposes. However, when inorganic powder is blended, the moldability of the synthetic resin generally deteriorates, which limits the amount of blending, and there are also drawbacks such as a decline in functionality due to poor dispersion of the inorganic powder and a decline in the mechanical strength of the molded product. there were.

In order to improve these drawbacks, many attempts have been made to make the surface of inorganic powder hydrophobic and to impart affinity with synthetic resins or organic reactivity, but none of them can be said to be satisfactory.

For example, silane coupling agents are known as modifiers for inorganic powders for the purpose of improving physical properties, but their use improves the rigidity of synthetic resin products, but improves processability, especially powder filling properties. There are few drawbacks such as improvement effects. In addition, processing agents aimed at improving processability include long chain fatty acids or their salts, titanium coupling agents, etc.
Although inorganic powder modified with such a modifier has some degree of affinity, the improvement effect described in (a) is still not sufficient.

Furthermore, the inorganic powder made from an organic phosphoric acid compound described in JP-A No. 11357-168954 is treated with a phosphoric acid ester compound and a phosphonic acid ester compound; 2 acidic ORs
The presence of groups increases the agglomeration of the powder during powder processing, and the free 0) I groups remaining on the powder surface cause gelation and curing of the resin, resulting in unsaturated polyester resins, epoxy resins, etc. When blended with a thermosetting resin, it has the disadvantage of causing a thickening phenomenon.

The present inventors have conducted various studies to improve the defects inherent in inorganic powder as described above, and have found that if the surface of inorganic powder is coated with a specific organic phosphate ester compound,
The present invention was completed after confirming that the dispersibility and filling properties in paints and resins were improved.

Organic phosphate ester compounds used in the present invention (however, B
, R/ are the same or different aliphatic or alicyclic organic groups having saturated, unsaturated or mercapto groups having 1 to 30 carbon atoms, n is 2 to 3, m 4''): t
~10(7) integer -r:hruo)Vc-c is an organic phosphoric acid ester compound.

The organic phosphoric acid ester compound can be synthesized by a known method, that is, by reacting phosphoric anhydride with an alcohol to form a mixture of monoester and diester, and then adding ethylene oxide or propylene oxide, or by adding ethylene oxide or propylene oxide. After the ester reaction between alcohol and alcohol, a highly pure modester or diester is produced through a purification step, and ethylene oxide or propylene oxide is added to the resulting mixture.

Examples of inorganic powders to be treated include silica, dolomite, mica, wollastonite, clay, Merck, calcium carbonate, magnesium carbonate, barium sulfate,
aluminum hydroxide, magnesium hydroxide, zinc oxide,
antimony trioxide, titanium oxide, iron oxide, ferrite,
There are wet treatment methods and dry treatment methods for modifying the surface of almost all inorganic powders such as iron, nickel, and copper. First, to explain the wet treatment method, inorganic powder is suspended in a slurry form in a solvent such as water or alcohol of the same volume or more, and 0.1 to 50% by weight, preferably 0.1% to 50% by weight, preferably 0% by weight, based on the surface of the inorganic powder, is stirred vigorously. .2～
Add io weight percent of treatment agent.

After thorough mixing, the mixture is filtered, and the resulting cake is dried and pulverized to obtain a modified inorganic powder.

Next, the dry processing method will be explained. The inorganic powder is placed in a Henschel type mixer capable of high-speed stirring and heating, and in the same manner as above, 0.1 to 50% by weight, preferably 0.2 to 10% by weight of the processing agent is mixed with an organic solvent 2 to 10 times. The diluted solution is added through the injection nozzle under high speed stirring. After thorough mixing, the temperature is gradually increased, and when the solvent is removed from the system, the mixture is stopped and cooled.

Although the treatment effect is almost the same whether the treatment is carried out by a wet treatment method or a dry treatment method, wet treatment is preferable in the case of metal powder due to the risk of explosion. In any case, an appropriate treatment method can be selected depending on the shape and type of the powder. When the inorganic powder modified with the organic phosphate ester compound used in the present invention is blended with various resins, Improvements in the organic phosphoric acid ester compounds used in the present invention, such as improved fluidity and dispersibility during processing of thermosetting resins, for example, viscosity-lowering effects in thermosetting resins and improvements in magnetic properties in magnetic recording media. The effects of quality medicines are always profound.

The present invention will be explained below using examples, but the present invention is not limited only to the examples.

Example 1 Put 100 parts by weight of aluminum oxide (H-32 manufactured by Showa Light Metal) into a high-speed mixer and add lθ% of 2.5 moles of ethylene oxide adduct of 1 red ester of sodium phosphate.
5 parts by weight of methanol solution was added, mixed under high speed stirring, and dried to obtain a modified inorganic powder.

Next, the obtained modified inorganic powder and untreated powder were each used as a filler of unsaturated polyester (Nippon Shokubai Kagaku S).
-355LT) 140 parts by weight per 100 parts by weight was mixed, and the viscosity when styrene was added was measured using a B-type viscometer. As a comparative example, a case using monolauryl phospade was also conducted.

The results are shown in Table 1. It can be seen that the single powder of the present invention exhibits a remarkable viscosity reducing effect compared to the untreated powder.

Table 1 Example 2 140 parts by weight of the modified inorganic powder obtained in Example 1 was blended with unsaturated polyester IQO1, and glass mat 4
Table 2 shows the results of an investigation of the bending strength retention at 70°C for a product manufactured under the conditions of 3 layers of #, ISO, and after-cure at 110°C for 2 hours.The modified inorganic powder according to the present invention It can be seen that the strength retention rate of the song is better than that of the untreated sample.

Table 2 (Note): The bending strength after molding was set to 100. .

Example 3 r -Fe20B was treated as an inorganic powder by a wet treatment method using 1 mole adduct of ethylene oxide of high purity didecyl phospade and 4 mole adduct of ethylene oxide of monodecyl phospade as treatment agents, each in 2 parts by weight. Make powder and -Fill! A magnetic coating material was produced according to the above method, and the magnetic recording medium was obtained by dispersing it on a polyester paste.The zero coercive force (Mc), degree of orientation, and electrical properties of the magnetic recording medium were measured by conventional methods, and the results are shown in Table 3. I got it.

Weight part Blend r-Fe203 to.

Thermoplastic polyurethane resin 16 Vinylidene chloride-acrylontrile copolymer 16th
3 Table.

(Note): As shown in Table 3, the electrical properties of a product treated with 1 mole of ethylene oxide adduct of didecylphospade were compared with the output properties at 10 Kfiz. is high, and on the other hand, the energy characteristics are also favorable on the high frequency side,
5 to 6 dB higher than untreated Example 4 Metallic iron magnetic powder was subjected to a wet processing method using 2 parts by weight of a 2.5 mol adduct of phosphoric acid stearyl ester with propylene oxide as a processing agent. A modified inorganic powder was prepared using the following composition as a magnetic coating material, and a magnetic tape was prepared by coating it on polyester. Table 4 shows the results of measuring the squareness ratio (B r /Bm) and #large maximum magnetic flux density CBm) using conventional methods.

Vinyl chloride vinegar Pea vinyl alcohol prepolymer 20 Acrylonitrile-butadiene copolymer 73 Functional polyisocyanate 3 Carbon black l. 4 Liquid paraffin 0.5 Methyl inbutyl ketone 100 Toluene 100 Table 4 It is well known that the dispersibility of magnetic powder has a large effect on the squareness ratio, packing property, and maximum magnetic flux density. The results also show that when a magnetic paint is prepared using the modified metal magnetic powder according to the present invention, the dispersibility of the magnetic powder in the binder and the filling property in the paint film are improved, resulting in excellent magnetic properties. It can be seen that a magnetic recording medium having the following characteristics can be provided.

Patent applicant: Daihachi Chemical Industry Co., Ltd.

Claims (1)

[Claims] (However, R and R' are the same or different carbon numbers 1 to 30.
(n is an integer of 2 to 3,
m is an integer from 1 to 10. ) An inorganic powder modified with an organic phosphorus ester compound.