PL198371B1 - Method for the modification of mineral pigments - Google Patents

Abstract

A method of modifying mineral pigments using a quaternary N-alkylammonium salt QAC, water glass SW and H2SO4, characterized in that to 5-10 volumes of a 50% aqueous solution of a quaternary N-alkylammonium salt QAC, preferably benzalkonium chloride, 10 volumes of 40% water glass SW and 5 to 10 volumes of water are added and mixed for 30 minutes, then while continuing mixing, a mineral pigment C, such as titanium dioxide, dolomite, bentonite, silica or others, is added to the solution in an amount of 10 to 15 kg per 20 liters of the aqueous solution QAC-SW, then 30 to 60 liters of water and 18% H2SO4 in an amount of 10 to 15 liters are slowly added and mixed for another 15 minutes, then the mixture is left for 2-3 hours, then it is filtered and the obtained product C(SiO2-QAC) washed with water and air-dried.

Description

The subject of the invention is a method of modifying mineral pigments by coating them with precipitates from a solution of fourth-order N-alkylammonium salt and water glass.

Mineral pigments, which are water-insoluble materials, such as titanium dioxide, dolomite, bentonite, silica and others, are used to produce paints, varnishes, mortars, etc. on plasters and other surfaces in construction. An extremely important issue, in addition to giving these materials the desired technical properties, is the protection of the obtained surfaces against the destructive action of microorganisms such as fungi, bacteria or algae. Typically, this is achieved by adding suitable biocides to paints or other building materials, which, however, penetrate into the ground with water, contaminating the environment. Therefore, in order to eliminate this type of risk, the construction industry should use biocidally effective materials insoluble in water.

From patent application P 357 356, biocide silica pigments are known which are combinations of the quaternary ammonium compound QAC (Quaternary Ammonium Compounds), preferably benzalkonium chloride with SW waterglass silica. These types of biocides can be used as additives to building materials. Their disadvantage, however, is their poor dispersibility with commercial resins used in the production of paints and varnishes, which limits the scope of their applications.

The QAC salt solution with the addition of SW water glass is dissolved in water in a limited concentration range. Adding more water causes the QAC-SW salt to slowly precipitate out of solution. It has been noticed that if any mineral pigment C is added to the aqueous QAC-SW salt solution with constant stirring and the amount of water is increased, the precipitated QAC-SW salt will coat the pigment C.

On the other hand, adding a certain amount of HSC to the solution stabilizes and fixes the layer that coats the pigment. After 20-30 minutes, this treatment produces a new mineral pigment C (SiO2-QAC) with biocide properties and insoluble in water.

The method of modifying the mineral pigments according to the invention consists in adding 10 volumes of 40% water glass SW and 5 to 10 volumes of water to 5-10 volumes of a 50% aqueous solution of the 4th grade N-alkylammonium salt QAC, preferably benzalkonium chloride, and mixing by 30 minutes, then, with continued stirring, the mineral pigment C, such as titanium dioxide, dolomite, bentonite, silica or others, is added to the solution in an amount of 10 to 15 kg per 20 liters of QAC-SW aqueous solution, then 30 to 60 liters of water are slowly added and 18% HSCU in an amount of 10 to 15 liters and stirring is continued for 15 minutes, then the mixture is left for 2-3 hours, then filtered and the obtained product C (SiO2-QAC) is washed with water and air dried.

The process according to the invention can be applied to any mineral pigment and the SiO2-QAC biocides can also be produced in fabrics.

The mineral pigments modified by the method according to the invention are characterized by the following properties:

- have biocidal properties,

- are insoluble in water,

- have a high dispersion ability with commercial resins used in the production of paints and varnishes,

- they show a strong affinity for anionic compounds, including acid dyes, which are a new type of color pigments, similarly to TiO2 absorb UV energy, synergism of UV effects, including biological ones, is expected in C (SiO2-QAC) materials with TiO2 admixture.

The use of mineral pigments C (SiO2-QAC) modified according to the invention in construction will bring a new quality to environmental protection, preventing its contamination. Fabrics made by saturation with QAC-SW salt and stabilized with H2SO4 can be used as antibacterial filters, dressings and more.

The following examples illustrate the invention without limiting its scope, and Examples I, II and III describe the preparation of aqueous QAC-SW salt solutions.

P r z k ł a d I

10 cm ^{3 of} a 50% aqueous benzalkonium chloride solution QAC (Bayer) was added a 20 cm ^{3 (40%)} beef ^{d g} o ne ^{SW (St} an ^d ar ^{d) and 20} cm ^{3 of} WO ^dy.

After stirring for 15 minutes, a completely clear QAC-SW solution was obtained.

PL 198 371 B1

P r z x l a d II

20 cm ³ of 50% aqueous benzalkonium chloride solution QAC (Bayer) was added with stirring cm ³ (4 ^{0%) kl} s and ^d ne wo ^g of SW (Standard) ^and 3 ⁰ cm ^{3 of} WO ^dy.

After stirring for 15 minutes, a completely clear QAC-SW solution was obtained.

P r x l a d III

To 10 cm3 of a 50% aqueous solution of Bardap 26 (Lariza) was added a 20 cm3 (40%) of the glass wo ^{d g} o ne ^{SW (St} an ^d ar ^{d) and 20} cm ^{3 of} WO ^dy.

After stirring for 15 minutes, a completely clear QAC-SW solution was obtained.

P r x l a d IV

To 20 cm3 of the QAC-SW solution obtained in example 1, 10 g of TiO2 was added with stirring and stirred for 15 minutes. Then, over 30 minutes, 60 cm 3 of water was slowly added with constant stirring and 18% H 2 SO 4 was added while stirring.

After stirring for 15 minutes, the mixture was left for 2 hours. At this time, the TiO2 product (SiO2-QAC) was filtered through a filter cloth, washed with water and air dried. No QAC was found in the filtrate

P r z k ł a d V

To 30 cm3 of the QAC-SW solution obtained in the example, 15 g of TiO2 was added while stirring and the procedure was continued as in Example IV.

The product TiO2 (SiO2-QAC) was obtained. No QAC was found in the filtrate.

P r x l a d VI

To 20 cm3 of the QAC-SW solution obtained in Example 1, 10 g of CaMg (CO3) 2 were added with stirring and the procedure was continued as in Example IV.

The product CaMg (CO3) 2 (SiO2-QAC) was obtained. No QAC was found in the filtrate.

Example VII

To 20 cm3 of the QAC-SW solution obtained in Example 1, 9 g of CaMg (CO3) 2 and 1 g of TiO2 were added while stirring, and the procedure was continued as in Example IV.

The product CaMg (CO3) 2TiO2 (SiO2-QAC) was obtained. No QAC was found in the filtrate.

P r x l a d VIII

To 20 cm3 of the QAC-SW solution obtained in Example III, 10 g of TiO2 was added while stirring, and the procedure was continued as in Example IV.

The product TiO2 (SiO2-QAC) was obtained, where QAC = Bardap 26. No Bardap 26 was detected in the filtrate.

The homogeneity of the pigments (uniformity of QAC bonding) was determined on the basis of their dyeing with acid dye Acid Green 25 (AG 25, Aldrich)

P r x l a d IX

0.5 g of dry product TiO2 (SiO2-QAC) prepared as in Example IV were mixed with 50 cm ^{3 of a 1%} beef ^{d g} o ne expansion form of ^{AG 25} ^ donation ¹ cm ^{3 of 10% H} 2 ^{SO 4.}

After 10 minutes, the dye was bound by the pigment which, after washing with water and air-drying, showed color uniformity.

Using the 2QAC-SW solution as in Example 2, the dye consumption in this example was twice as high to obtain a dry TiO2 product (SiO2-2QAC).

Claims (1)

A method of modifying mineral pigments using QAC IV N-alkylammonium salt, SW water glass and H2SO4, characterized in that to 5-10 volumes of a 50% aqueous solution of QAC IV N-alkylammonium salt, preferably benzalkonium chloride, is added 40% water glass SW and 5 to 10 volumes of water and mixed for 30 minutes, then, with continued stirring, a mineral pigment C such as titanium dioxide, dolomite, bentonite, silica or others is added to the solution in the amount of 10 to 15 kg per 20 liters of QAC-SW aqueous solution, then 30 to 60 liters of water and 18% H2SO4 in the amount of 10 to 15 liters are slowly added and stirred for another 15 minutes, then the mixture is left for 2-3 hours, then filtered, and the obtained product C (SiO2-QAC) is washed with water and air dried.