HU197339B - Process for producing bond accelerating and strengthening additive and powdered coating composition comprising same - Google Patents

Abstract

The present invention relates to a process for the production of a binder-accelerator and an additive which contains boric acid salt and clay mineral. According to the process of the present invention, an alkali borate, preferably borax and SiO -ban, in a weight ratio of 5: 2 to 1:10, is homogenized in anhydrous form by 35-70% Si-containing clay, preferably kaolin. The present invention also provides a powder coating material comprising from 2 to 10% by weight of the additive prepared according to the above process or from 2 to 5% by weight of borax and from 2 to 5% by weight of the above-mentioned clay minerals from 1 to 10% by weight of water-soluble cellulose derivatives. 95% by weight of pigment and / or filler and optionally other additives, preferably wetting agents, non-ionic surfactants, preservatives, water softeners and degreasing agents, perfumes and mold inhibitors. 197339 -1-

Description

The present invention relates to a process for the preparation of a bond accelerator and a bond enhancer comprising a boric acid salt and a clay mineral. In the process, the two starting components are mixed homogeneously on a powder mixer. The present invention relates to a powder coating composition comprising an additive prepared according to the above process, which is a mixture of boron and clay minerals having a weight ratio of 2-10 tX 5: 2 to 1:10 and expressed as SiO 2 in gX in anhydrous form, or 2-5 tX. in addition to tX borax and 2-5 tx Si-containing clay as above, 1-10 tx water-soluble cellulose derivative, 65-95% pigment and / or filler, and optionally other additives as required for 100 tX, preferably nonionic surfactant. , preservative, water softener and degreaser, fragrance and anti-mold.

Many disadvantages of conventional powder wall paints are known (Kovács: Pocket Book of Lacquer and Paint, Technical Publishing House, 1982, pp. 304-307):

Of the traditional powder-based wall paints, the preparation of lime-hydrate-based ones, due to their highly alkaline pH, can only be done with great care, and they have to be corroded with great care. The properties of the lime hydrate coating develop only after a very long time, after complete carbonation. Such a coating is virtually impossible to clean, has a low mechanical resistance and is easily dust-painted.

Preparation and use of another major group of conventional powder formulations, adhesives of vegetable and / or animal origin, require great skill and practice, since the properties of the coating are highly dependent on the manner in which the paint is prepared. Coatings with adhesive binders have poor coating properties, are non-waterproof and difficult to repaint. The adhesive binders are decomposable, the wall coating produced by their application (Especially in humid rooms and near thermal bridges) can be a medium for bacteria and fungi and there is a risk of mold.

To overcome these disadvantages, formulations containing polymeric dispersions have been developed. These state-of-the-art and widely used wall paints have several unavoidable disadvantages along with their many advantageous properties. These include:

- usually contain about 50 tx of water, which results in additional costs for transport, storage and packaging, and further frost hazard of the product;

- increase the vapor diffusion resistance of the coated surface and consequently the risk of condensation and fungus;

- although the paint itself can be thinned with water, dripping and dried paint stains can only be removed with aggressive, flammable solvents.

In addition to the development of dispersion wall paints, traditional powder coatings (mainly containing cellulose derivatives) have also been developed. The results obtained in this area are illustrated by the following examples:

The coating material described in Japanese Kokai Tokyo Koho 79 31 444 (08.03.1979 CA 91, P 58810 y) improves the lubricity of a conventional combination of Na-CM cellulose and pigment by the addition of clay. The applied silicate clay minerals (bentonite, attapulgite, montmorillonite) also have a beneficial effect on the stability of the aqueous dispersion of the powder.

Czechoslovakian Patent Application No. 181,400 discloses water-dispersible wall paint in powder form which contains 4.5-65.0 tX carboxymethylcellulose, 3.0-38.0 tX other water-soluble cellulose derivatives, 0.1-8.0 tx fungicidal material and 90 -20 tX contains inorganic or organic pigment. Fungicides include: 8-oxyquinoline and its salts, salicylanilide sodium salt, zinc stearate, sodium borate or perborate, sodium benzoate, p-sulfamide benzoate sodium salt, and the like. Inorganic pigments: micronized dolomite, clay minerals (canoline), whitish white, etc., organic pigments are dyes painted with organic dyes.

In order to eliminate the disadvantages of the known powder coating materials, we have endeavored to develop an indoor coating material, which can be produced using domestic raw materials as far as possible, which meets environmental protection requirements and does not cause occupational safety problems.

Surprisingly, it has been found that, when boric acid salt and clay minerals are used together as an additive, such additive is required to synergistically reduce the amount of suspending, film-forming and coating properties of water-soluble cellulose derivatives as film-forming agents.

It has been found that from a 5: 2 to 1:10 weight ratio of components, a mixture of boric acid salts (especially alkali borate, preferably borax, disodium tetraborate) and clay minerals (having a Si content of S1O2 in anhydrous form of 35-70 tX, preferably kaolin) contacting (preferably homogenizing on a powder mixer) yields an additive which, when applied, positively influences the properties of the powdery indoor coatings, increases the speed of bonding and strengthens the bond to the coated surface.

Further, it has been found that the 2-10% strength bonding and bond accelerating composition prepared in the above manner has a very favorable effect on the properties of the powder coating material: a synergistic effect has been found in anhydrous form 35-70% by weight of a mixture of leather and clay with an Si content of 35-70% or with 2-5% by weight of borax and 2-5% by weight of anhydrous soluble cellulose derivative, 1-10% by weight, -95% by weight of pigment and / or filler and optionally other additives of 100% by weight, preferably a nonionic surfactant, a preservative, a water softener and a grease remover, a fragrance and an anti-mold agent.

Preferably, the water-soluble cellulose derivative of the present invention is a sodium salt of methyl, hydroxyethyl, hydroxypropyl, and carboxymethylcellulose. Preferred pigments include titanium dioxide, lithopone, zinc white, iron oxide pigments, fillers include dolomite, limestone, alumina, talc, and barite. Among the preferred nonionic wetting agents, ethoxylated fatty alcohols and polyglycol esters of fatty acids are preferred for environmental reasons. Any preservative permitted by MSZ 20030-87 may be used as a preservative, and due to its availability, chloroacetamide is preferred. Sodium or potassium tripolyphosphate were used as water softening and degreasing components. Copper stearate, ethylene bis (dithiocarbamethyl) manganate polymer (trivially known as Maneb) or a zinc version of the same compound (Cineb) as an anti-mold agent; these mold inhibitors have very low animal toxicity: their LD50 in acute oral treatment is 6000-7000 mg / kg in rats. Because of the freshness of the fragrance of your choice, the fragrance of pine (pineoyl), lemon (for example, 80 073 K by Orissa Dressing GMBH, Hamburg Citronia) or apple (fragrance by Apfel 76 716 from the same company).

The process for the preparation of the binder accelerator and binder reinforcement according to the invention is illustrated by the following examples:

(t%) Homogenize on a mortar mixer for 30 minutes.

Example 3 (process)

100 parts by weight of borax and 100 parts by weight of kaolin (Si content 58% by weight as above) were homogenized by roller passage for 40 minutes.

The powder coating material of the present invention was prepared as follows:

The pre-ground components in the coating pan are homogenized for 40-60 minutes after weighing on a suitable powder mixer (Shutter mixer or Roller passage).

For the classification of powder coating materials, the usual (application-specific) methods used by ÉMI and KERMI were used:

Suspendability: 100 g of water is added to 100 g of water at 100C in a stirred vessel at 20 ° C and after 10 minutes of stirring, the resulting suspension is filtered through a 6000 mesh screen. 10 minutes after completion of the drip, the weight of the filtrate was determined and this was expressed as a percentage of the total weight of the starting materials; perfect suspendability equivalent to 100%.

Changes in abrasion resistance over time were used to demonstrate bond speed and bond strength increase. The resistance to abrasion was graded as follows: 100 g of the composition were suspended in 100 g of water and stirred for 4 hours to allow the system to rest. 200 g / m ² of the resulting slurry is applied to the asbestos cement board with a brush. 8, 24 and 168 hours drying! over time, qualify abrasion resistance by dragging a 5x5 cm black canvas over a 10 cm path at 100 g load. The abrasion resistance is scored from 0 to 5: 0 if there is no white discoloration on the black screen, 1 if traces of white discoloration and 5 if the whole surface is white.

The powder coating compositions of the present invention are illustrated by the following examples:

EXAMPLE 1 (Process) Homologated in parts by weight of borax and 170 parts by weight of kaolin (% SiO2 in SiO2) in anhydrous form in a 66% ball mill for 30 minutes.

Example 2 (process)

140 parts by weight of borax and 60 parts by weight of bacovite (Si content as above 4

Example 1

19.5% by weight of additive prepared according to Example 1 33.0% by weight dolomite 33.0% by weight limestone 4.0% by weight alumina

2.5% by weight of titanium dioxide

7.0% methylcellulose (2% aqueous solution at 20 ° C, 500 mPa.s)

-3197339

0.5 tX potassium tripolyphosphate

0.5 tX chloroacetamide

Suspensibility: 97 X; abrasion resistance after 8 hours 2, after 24 hours 0-1, after 168 hours 0; Capacity: 220 g / m ² applied in three coats 5 applied.

Example 2 ¹⁰

2.5 tX of the additive prepared in Example 2 of the method

30.8 tX Limestone Ground

30.8 tX Dolomite Ground

29.9 tX alumina powder 15

4.5 tX zinc white pigment

0.5 tX potassium tripolyphosphate

1.0 tX hydroxymethylcellulose (viscosity of a 2 tX aqueous solution at 3700 mPa.s at 20 ° C) 20

Suspendability: 95 X; abrasion resistance after 8 hours 1, 24 hours 1, 168 hours 0; Capacity: 180 g / m ² applied in three coats.

Example 3

2.5 tX borax

2.5 tX kaolin powder (Si content in 30 SiOr, calculated on an anhydrous basis at 66 tX)

2.5 tX alumina powder at 10.0 tX lithopone

78.0 tX Limestone Ground 35

4.0 tX carboxymethylcellulose sodium salt (2 tX aqueous solution has a viscosity of 50 mPa.s)

40 esters of 0.5 tX C12-C1S fatty acids with 6 glycol units of polyglycol

Suspensibility: 96 X; abrasion resistance:

1 hour after 24 hours, 0-1 after 24 hours, 0 after 168 hours; Capacity: 200 g / m ² applied in three coats. 45

Example 4

2.0 tX Borax 50

18.0 tX kaolin meal (as in Example 3)

10.0 tX Carboxymethylcellulose sodium salt (viscosity of a 2 tX aqueous solution at 50 ° C at 20 mPa.s) 55

40.0 tX limestone powder at 25.0 tX lithopone

0.5 tX Cu-Cis fatty alcohol ethoxylate (mean ethox number 15)

0.2 tX pineoil (odors) 60

0.3 tX Maneb (Mold Inhibitor)

3.5 tX sodium tripolyphosphate

Suspendable: 99X; abrasion resistance: 0 after 8 hours, 0 after 24 hours, 0 after 168 hours;

Capacity: 140 g / m ² applied in three coats.

Example 5

2.0 tX is the additive prepared according to the method of Example 1

1.0 tX methylcellulose (viscosity of an aqueous solution of 1.0 tX-οβ at 4200 mPa.s)

85.0 tX limestone powder 8.0 tX lithopone 4.0 tX titanium dioxide

Suspensibility: 92X; abrasion resistance: 2 after 8 hours, 1 after 24 hours, 0 after 168 hours; Capacity: 150 g / m ² applied in three coats.

Comparative Example: (Based on Czechoslovak Patent Application No. 181,400)

10.0 tX carboxymethylcellulose sodium salt (viscosity of a 2 tX aqueous solution at 50 ° C at 20 mPa.s)

9.0 tX dextrin (enzymatically degraded, gray dextrin)

0.5 tX triethylene glycol adipate (molecular weight: 480)

0.5% salicylic acid 0.1tX8-oxyquinoline

Uncle 40.0 tX

39.9 tX Limestone Ground

Suspensibility: 91 X; abrasion resistance:

3 hours after 24 hours, 2-3 after 24 hours, 2 after 168 hours; coating capacity: 280 g / m ² applied in three coats (according to Example 2 of the above patent).

comparative example / 2.

20.0 tX carboxymethylcellulose sodium salt (as above)

12.0 tX dextrin (as above)

2.0 tX Hydroxyethylcellulose (Viscosity of a 2 tX aqueous solution at 680 mPa.s at 20 ° C)

1.0 tX glycerol

0.5% stearin soap

0.1 tX salicylanilide sodium salt

0.5 tX borax

0.5 tX sodium benzoate 0.1 tX jasmine scent 26.0 tX kaolin 37.3 tX limestone flour

Suspensibility: 93X; abrasion resistance: 4 hours after 8 hours, 3 after 24 hours, 2 after 168 hours; coating capacity: 250 g / m ² applied in three coats (according to example 4 of the above patent).

Comparison of the formulations of the present invention with those of the comparative examples shows that significantly simpler formulations, less polymer use, achieved better abrasion resistance and higher coverage.

Claims (6)

PATENT CLAIMS A process for the preparation of a bond accelerator and a bond enhancer comprising:. to a powder mixture of alkali metal borate, preferably borax and clay, having a Si content of 10 S1O2 in tX, expressed in anhydrous weight of 35-70% by weight, preferably kaolin 5: 2-1: 10, preferably 1: 1-1: 6 in a known manner, homogeneous. 15 2. A powder coating composition comprising a mixture of borax and clay minerals containing 2 to 10% by weight, 5 to 2 to 1:10% by weight and 35% to 70% by weight of S1O2, based on Si anhydrous, or 2 to 5% by weight. 1% to 10% by weight of water-soluble cellulose derivative, 65 to 95% by weight of pigment and / or filler and, if necessary, other additives for 100% by weight preferably 25 as non-ionic surfactants, preservatives, water softeners and degreasers, fragrances and anti-mold agents as wetting agents. 3. The composition of claim 2, wherein the water-soluble cellulose derivative is methyl, hydroxyethyl, hydroxypropylcellulose or carboxymethylcellulose sodium. Composition according to claim 2, characterized in that the pigment is titanium dioxide, lithopone, zinc white, iron oxide or a mixture thereof. Composition according to claim 2, characterized in that the filler is dolomite, limestone, alumina, talc, barite or a mixture thereof. 6. The composition of claim 2, wherein the nonionic surfactant used as a wetting agent is an ethoxylated fatty alcohol or polyethylene glycol ester of a fatty acid, a preservative chloroacetamide, antifouling copper stearate, ethylene bis (dithiocarbamate) diphenyl carbamate or zinc polymer, the water softening and degreasing component being sodium or potassium tripolyphosphate.