Process for producing composite particles and insulation material for the production of insulating products for the building materials industry, and corresponding uses

Abstract

What are described are a process for producing an insulating product for the construction materials industry or an insulating material as intermediate for production of such a product, and a corresponding insulating material/insulating product. Also described are the use of a matrix encapsulation method for production of composite particles in the production of an insulating product for the construction materials industry or of an insulating material as intermediate for production of such a product, and the corresponding use of the composite particles producible by means of a matrix encapsulation method.

Claims

1. A process for producing fireproofing material, a thermal or sound insulating product, or an insulating material as intermediate for production of such a product, the method comprising the following steps: (a) producing composite particles having a grain size of less than 10 mm, determined by sieving, in a matrix encapsulation process having the following steps: (a1) producing droplets of a suspension composed of at least the following starting materials: as dispersed phases (i) one or more substances selected from the group consisting of sheet silicates and clays, (ii) additionally one or more density-reducing substances selected from the group consisting of lightweight fillers having a respective bulk density in the range from 10 to 350 g/L, blowing agents and pyrolyzable fillers and (iii) one or more nonrefractory solids for reducing the melting point of the composite particles in addition to constituents (i) and (ii), and as continuous phase (iv) a solidifiable liquid, (a2) solidifying the solidifiable liquid, such that the droplets harden to give hardened droplets, and the (i) substance(s) selected from the group consisting of sheet silicates and clays, the (ii) density-reducing substance(s) and the (iii) nonrefractory solid(s) are encapsulated in the solidifying continuous phase, (a3) treating the hardened droplets so as to result in said composite particles, the treating comprising a sintering of the hardened droplets, wherein the composite particles produced in step (a3) comprise a continuous solid phase that extends from center to outer surface of the composite particle; and (b) producing the fireproofing material, thermal or sound insulating product, or the insulating material as intermediate for production of such a product using the composite particles from step (a).

2. The process as claimed in claim 1, wherein the one or more nonrefractory solids for reducing the melting point of the composite particles that are used as additional starting material (iii) are inorganic materials selected from the group consisting of amorphous oxides, amorphous silicates, crystalline oxides and crystalline silicates and mixtures thereof, and/or having a melting point or softening temperature lower than 1350° C., and/or selected from the group consisting of glass flours, feldspar, boric acid and boron salts.

3. The process as claimed in claim 1, wherein the one or more nonrefractory solids for reducing the melting point of the composite particles that are used as additional starting material (iii) are inorganic materials selected from the group consisting of amorphous oxides, amorphous silicates, crystalline oxides and crystalline silicates and mixtures thereof, and having a melting point or softening temperature lower than 1350° C., and/or selected from the group consisting of glass flours, feldspar, boric acid and boron salts.

4. The process as claimed in claim 1 wherein the insulating product produced for the construction materials industry or the insulation material produced as intermediate for production of such a product is selected from the group consisting of: indoor and outdoor wall and roof linings, construction panels, and/or acoustic panels; indoor and outdoor render systems, render and drying mortar systems, tile adhesives, construction adhesives, leveling compounds, spackling compounds, sealing compounds, filling compounds, wall fillers and/or loam renders; emulsion paints and/or wallpapers, and resin systems for the construction materials industry.

5. The process as claimed in claim 1, wherein step (a1) further comprises adding a coloring agent for white color, wherein at least one of the following is true: the coloring agent is in constituent (i) and the coloring agent is one or more substances selected from the group consisting of sheet silicates and clays; the coloring agent is in constituent (iii) and the coloring agent is one or more nonrefractory solids for reducing the melting point of the composite particles; the coloring agent is an additional constituent used as one or more additional starting materials.

6. The process as claimed in claim 1, wherein the or at least one of the lightweight fillers used in step (a) as density-reducing substance of component (ii) is selected from the group consisting of: inorganic hollow beads, organic hollow beads, particles of porous and/or foamed material, rice husk ash, core-shell particles and calcined kieselguhr, and/or wherein the or at least one of the blowing agents used in step (a) as component (ii) is selected from the group consisting of: carbonates, hydrogencarbonates, oxalates, vegetable flours, selected from the group consisting of coconut shell flour, walnut shell flour, grape seed flour, olive kernel flour, wheat flour, corn flour, wood flour, sunflower husk flour and cork flour, starch, potato dextrin, sugars, plant seeds, and rice husk ash, and/or wherein the or at least one of the pyrolyzable fillers used in step (a) as component (ii) is selected from the group consisting of: polymer beads and styrofoam beads.

7. The process as claimed in claim 6, wherein the or at least one of the lightweight fillers used in step (a) as density-reducing substance of component (ii) has a grain size of less than 0.4 mm determined by sieving.

8. The process as claimed in claim 1, wherein one or more refractory solids are used in step (a1) as additional starting material for production of a further dispersed phase, wherein the or at least one of the refractory solids used additionally in step (a1) is selected from the group consisting of: oxides of one or more elements from the group consisting of Si, Al, Zr, Ti, Mg and Ca, and mixed oxides each comprising one or more elements from the group consisting of Si, Al, Zr, Ti, Mg and Ca.

9. The process as claimed in claim 8, wherein at least one of the refractory solids used additionally in step (a1) is selected from the group consisting of: aluminum oxide, zirconium oxide, titanium dioxide, silicon dioxide, magnesium oxide, calcium oxide, calcium silicate, sheet silicates, aluminum silicates, and magnesium aluminum silicate.

10. The process as claimed in claim 9, wherein the sheet silicates are mica.

11. The process as claimed in claim 1, wherein the or at least one of the substance(s) used in step (a1) as substance of component (i) is selected from the group consisting of sheet silicates and clays that do not melt in an incongruent manner below 1500° C. and/or is selected from the group consisting of the sheet silicates selected from the group consisting of kaolinite, montmorillonite and illite, and the clays selected from the group consisting of kaolin and bentonite and/or wherein said resultant composite particles in step (a3) have a bulk density <500 g/L, and/or wherein all or some of the resultant composite particles in step (a3) have a grain size of <1.5 mm, determined by sieving.

12. The process as claimed in claim 1, wherein component (ii) comprises, as density-reducing substance(s), one or more blowing agents and the treating in step (a3) is conducted in such a way that the one or more blowing agents expand and hence form cavities in the resultant composite particles and/or one or more pyrolyzable fillers and the treating in step (a3) is conducted in such a way that the one or more pyrolyzable fillers pyrolyze and hence form cavities in the resultant composite particles, and/or wherein component (i) in step (a1) comprises at least one clay, and/or wherein the treating in step (a3) comprises sintering at a temperature in the range from 900 to 980° C., forming a sintered composite comprising components (i), (ii) and (iii), and/or wherein the sintering in step (a3) does not exceed a temperature of 1000° C., and/or wherein the hardened droplets are sintered in step (a3) so as to result in solid particles as intermediate, and wherein a surface of these solid particles is subsequently sealed, so as to result in said composite particles.

13. The process as claimed in claim 1, wherein the resultant composite particles in step (a3) are characterized by (A) a whiteness W≥65, and/or (B) a thermal conductivity value at room temperature (20° C.) γR of ≤0.26 W/m*K, and/or (C) an alkali stability, determined as the weight loss in the course of storage in sodium hydroxide solution at pH 14 for 30 days, of ≤9% by mass, based on composite particles having a grain size in the range of 0.5-1.0 mm, and/or (D) a grain strength ≥1.5 N/mm2, determined to DIN EN 13055-1:2008-08, Annex A (Method 1, agitating for 2*30 s with amplitude 0.5), at a grain size in the range of 0.25-0.5 mm, and/or (E) a water absorption capacity, determined via water absorption according to Enslin, of ≤2.5 mL/g, and/or (F) a water solubility, determined as the weight loss in the course of storage in distilled water for 30 days, of ≤2% by mass, based on composite particles having a grain size in the range of 0.5 to 1.0 mm, and/or (G) a softening temperature ≥900° C., determined by heating microscopy.

14. The process of claim 1, wherein the hardened droplets are solid.

15. The process of claim 1, wherein droplets are provided in step (a1) by means of one or more nozzles, and/or wherein the solidifying of the solidifiable liquid in step (a2) is induced by cooling, drying or chemical reaction, and/or wherein the solidifiable liquid used in step (a1) is a liquid solidifiable by chemical reaction and in step (a2) the solidifying of the solidifiable liquid is induced by chemical reaction, and/or a liquid solidifiable by cation exchange reaction, and/or a liquid solidifiable by reaction with calcium ions, comprising one or more binders selected from the group consisting of alginate, PVA, chitosan and sulfoxyethyl cellulose, and/or an aqueous solution, wherein the solidifiable liquid is an aqueous alginate solution.

16. The process of claim 15, wherein the continuous solid phase is homogeneous.

17. The process of claim 1, wherein the continuous solid phase is homogeneous.

Description

FIGURES

(1) FIG. 1 shows inventive composite particles C19 after sintering (heating to 950° C. for 30 min., step (a3)). Light micrograph, 200-fold magnification.

(2) As can be seen in FIG. 1, a sintered composite within an (individual) composite particle was formed under the process conditions. Such a sintered composite is one cause of the exceptional mechanical stability of the composite particles of the invention.

(3) FIG. 2 depicts the shape of the sample cube (projection) pressed from the commercial expanded glass Liaver® (see example 2 for more details) before commencement of heating microscopy. The image is characterized by the following corresponding technical data:

(4) 18° C./00:00:00//area: 100%/form factor: 0.682//height: 100%/width: 100%//vertex angle on left: 78°/on right: 70°//wetting angle on left: 118°/on right: 84°

(5) FIG. 3 depicts the shape, altered by the effect of temperature, of the sample cube pressed from the commercial expanded glass Liaver® at a temperature of 1250° C. (projection). The image is characterized by the following corresponding technical data: 1250° C./00:23:51.

(6) It is readily apparent that, at a temperature of 1250° C., the original cube shape is lost and the expanded glass has completely melted. This indicates that the commercial expanded glass Liaver® does not have heat resistance to 1250° C.

(7) FIG. 4 depicts the shape of the sample cube (projection) pressed from the commercial foamed glass Forayer® (see example 2 for more details) before commencement of heating microscopy. The image is characterized by the following corresponding technical data:

(8) 22° C./00:00:00//area: 100%/form factor: 0.716//height: 100%/width: 100%//vertex angle on left: 82°/on right: 100°//wetting angle on left: 71°/on right: 81°

(9) FIG. 5 depicts the shape, altered by the effect of temperature, of the sample cube pressed from the commercial foamed glass Forayer® at a temperature of 1250° C. (projection). The image is characterized by the following corresponding technical data: 1250° C./00:22:13.

(10) It is readily apparent that, at a temperature of 1250° C., the original cube shape is lost and the foamed glass has completely melted. This indicates that the commercial foamed glass Forayer® does not have heat resistance to 1250° C.

(11) FIG. 6 depicts the shape of the sample cube (projection) pressed from C19 composite particles produced by the process of the invention before commencement of heating microscopy. The image is characterized by the following corresponding technical data:

(12) 20° C./00:00:00//area: 100%/form factor: 0.722//height: 100%/width: 100%//vertex angle on left: 95°/on right: 88°//wetting angle on left: 97°/on right: 76°

(13) FIG. 7 depicts the shape of the sample cube (projection) pressed from C19 composite particles produced by the process of the invention at a temperature of 1250° C. The image is characterized by the following corresponding technical data: 1250° C./00:23:49.

(14) It is readily apparent that, at a temperature of 1250° C., the original cube shape has been largely conserved; only the cube dimensions are reduced (sintering). This indicates that C19 composite particles produced by the process of the invention are heat-resistant at least to 1250° C.

EXAMPLES

(15) The present invention is elucidated in detail hereinafter by examples:

(16) Determination and Measurement Methods:

(17) 1. Grain Size Determination:

(18) The determination of the grain sizes of composite particles by sieving is effected in accordance with DIN 66165-2 (4.1987) using Method F specified therein (machine sieving with moving individual sieve or sieve set in gaseous static fluid). A vibratory sieving machine of the RETSCH AS 200 control type is used; the amplitude is set here to level 2; there is no interval sieving; the sieving time is 1 minute.

(19) The determination of the grain sizes of lightweight fillers used in step (a) as density-reducing substance of component (ii) is likewise effected in accordance with DIN 66165-2 (4.1987) using Method F specified therein (machine sieving with moving individual sieve or sieve set in gaseous static fluid). A vibratory sieving machine of the RETSCH AS 200 control type is likewise used; the amplitude is set here to level 2; there is no interval sieving; the sieving time is 1 minute.

(20) The determination of the grain sizes of refractory solids having a grain size of less than 0.1 mm is effected by sieving to DIN 66165-2 (4.1987) using Method D specified therein (machine sieving with a static individual sieve in gaseous moving fluid, with air jet sieve).

(21) 2. Determination of Bulk Density:

(22) The bulk density of each of the samples was determined to DIN EN ISO 60 2000-1.

(23) 3. Determination of Water Absorption Capacity:

(24) The determination of the water absorption capacity of the samples was determined by the Enslin method by means of an “Enslin apparatus”. A glass suction filter is connected here via a hose to a graduated pipette. The pipette was mounted horizontally such that it lay at exactly the same height as the glass frit. A water absorption of 1.5 mL/g thus corresponds to a water absorption of 1.5 mL of water per 1 g of composite particles. The evaluation was to DIN 18132:2012-04.

(25) 4. Determination of Chemical Composition and Morphology:

(26) The morphology was determined using a VisiScope ZTL 350 light microscope with a Visicam 3.0 camera.

(27) 5. Determination of Whiteness

(28) The whiteness was determined by the Tappi method (R457 whiteness), measured with a Minolta CM-2600 d spectrometer (see details from the manufacturer at its website at the address: https://www.konicaminolta.eu/de/messgeraete/produkte/farbmessung-glanzmessund/spektralphotometer-portabel/cm-2600 d-cm-2500d/technische-daten.html) with the following settings: mask average (MAV); measurement with and without specular component (SCI+SCE) and 0% UV component. The measurements are read out with the following specifications: standard illuminant C, observer angle 2° (C-2), without specular component and with 0% UV (SCE/0). The following “L*a*b values” are used: D65-10, SCI/0 (standard illuminant D65, observer angle 10° (D65-10) including specular component and 0% UV (SCI/0).

(29) 6. Determination of Thermal Conductivity Value

(30) The thermal conductivity values of the samples were determined in accordance with standard DIN EN 12667:2001-05, “Determination of thermal resistance by means of guarded hot plate and heat flow meter methods (Products of high and medium thermal resistance)”.

(31) 7. Determination of Alkali Stability

(32) The alkali stability of the samples (composite particles) was determined by the following method: 5 g of the composite particles to be examined were weighed out, covered completely with aqueous sodium hydroxide solution (pH 14) and thus left to stand under laboratory conditions (25° C., standard pressure) for 30 days. Subsequently, the composite particles were filtered out of the sodium hydroxide solution, washed to neutrality with water, dried (drying cabinet, 105° C.) and weighed. The weight loss after storage in the sodium hydroxide solution compared to the original starting weight of the composite particles was used as a measure of their alkali stability.

(33) 8. Determination of Water Solubility

(34) The water solubility of the samples (composite particles) was determined by the following method: 5 g of the composite particles to be examined were weighed out and covered completely with water by adding 100 mL aq. dist. and thus left to stand in a closed glass vessel under laboratory conditions (25° C., standard pressure) for 30 days. Subsequently, the composite particles were filtered off, dried (drying cabinet, 105° C.) and weighed. The weight loss after storage in water compared to the original starting weight of the composite particles was used as a measure of their water solubility.

(35) 9. Determination of the Softening Temperature of Composite Particles of the Invention

(36) The softening temperature of the samples was preferably determined by heating microscopy with an EM 301 (model M17) heating microscope from Hesse Instruments, Germany (see the relevant details on the website at the following address: http://www.hesse-instruments.de/content/products.php?Hllang=de) with selection of the following measurement conditions: 1st heating rate: 80 K/min until attainment of 700° C. (no hold time); 2nd heating rate: 50 K/min until attainment of 1500° C. (no hold time) and 3rd heating rate at 10 K/min until attainment of 1650° C. (hold time 5 s). The time of attainment of the softening temperature was determined to standard DIN 51730 (1998-4) (or ISO 540:1995-03).

Example 1: Production of Composite Particles by the Process of the Invention

(37) By step (a) of the process of the invention, composite particles (C01, C17, C19, C23, C27, C29 and C30) were produced with a grain size of less than 10 mm, preferably less than 2 mm (also referred to hereinafter as “composite particles of the invention”):

(38) (a1) Producing Droplets of a Suspension of Starting Materials:

(39) A 1% aqueous sodium alginate solution was produced (1% by weight of sodium alginate from Alpichem with CAS No. 9005-38-3, based on the total mass of the aqueous solution).

(40) The Sokalan® FTCP 5 dispersant from BASF was diluted with water to prepare a corresponding dispersion solution; the mass ratio of Sokalan® FTCP 5 to water was 1:2.

(41) The 1% aqueous sodium alginate solution prepared and the dispersion solution prepared were subsequently mixed in a mixing ratio according to table 1a or 1b, so as to give a solidifiable liquid (solidifiable liquid for use as continuous phase in the sense of constituent (iv) in step (a1)).

(42) While stirring, sheet silicates and/or clays (constituent (i) in step (a1)) and nonrefractory solids (constituent (iii) in step (a1)) selected according to table 1a or 1b below were then added to the solidifiable liquid until a creamy suspension was formed.

(43) While continuing to stir, density-reducing substances (constituent (ii) in step (a1), lightweight fillers, blowing agents or pyrolyzable substances, each according to table 1a or 1b) were then added in an amount according to table 1 below to the creamy suspension, followed by an amount of water according to table 1a or 1b.

(44) The result in each case was a diluted suspension.

(45) TABLE-US-00001 TABLE 1a Ingredients for production of composite particles of the invention and bulk densities resulting therefrom Composition of Ingredients the suspension Starling material Constituent Manufacturer (parts by weight) Sheet silicate (i) Kaolin Satintone ® W; BASF 15.5 15.5 10.6 10.6 or clay CAS RN 92704-41-1 [% by wt.] (i) Bentonit Volclay ® CAS Clariant 3.1 3.1 — — RN 1302-78-9 Nonrefractory (iii) Albit 45 (feldspar) CAS Ziegler & Co. — — 10.6 10.6 solid RN 68476-25-5 GmbH (iii) Poraver flour (glass flour) Dennert Poraver 15.5 15.5 14.2 16.0 CAS RN 65997- 17-3 GmbH (iii) Flat glass flour DIN 100, — — — — CASRN65997- 17-3 Lightweight (ii) Borosilicate glass beads 3M Deutschland 0.5 — — — filler CAS RN 65997- 17-3 and GmbH [% by wt.] 7631-86-9 Pyrolyzable (ii) Polymer beads PM 6550 Kish Company — — — — filler Inc. [% by wt.] (ii) Polymer beads Akzo Nobel — 0.5 0.8 0.8 Expancel ® 920 DE 80 CAS RN 38742-70-0 1% sodium (iv) Sodium alginate; Applichem 45.5 45.5 46.7 46.7 alginate CAS: 9005-38-3 solution [% by wt.] Dispersion (iv) Sokalan ® FT CP5 in BASF 2.8 1.8 1.9 1.9 solution water (1.2) [% by wt.] Water 18.2 18.2 14.3 12.5 [% by wt.] Resulting composite particles of the invention C01 C17 C19 C23 Resulting bulk density [g/L], based on grain sizes 0-1.5 mm 430 420 340 370

(46) TABLE-US-00002 TABLE 1b Ingredients for production of composite particles of the invention and bulk density resulting therefrom (continuation of table 1a) Composition of Ingredients the suspension Starting material Constituent Manufacturer (parts by weight) Sheet silicate (i) Kaolin Satintone ® W; BASF 10.6 10.0 10.5 or clay CAS RN 92704-41-1 [% by wt.] (i) Bentonit Volclay ® Clariant — — — CAS RN 1302-78-9 Nonrefractory (iii) Albit 45 (feldspar) Ziegler & Co. 10.6 10.0 10.5 solid CAS RN 68476-25-5 GmbH (iii) Poraver flour (glass flour) Dennert Poraver 14.2 — — CAS RN 65997-17-3 GmbH (iii) Flat glass flour DIN 100, — 20.0 18.0 CAS RN65997-17-3 Lightweight (ii) Borosilicate glass beads 3M Deutschland — — — filler CAS RN 65997-17-3 and GmbH [% by wt.] 7631-86-9 Pyrolyzable (ii) Polymer beads PM 6550 Kish Company 0.8 0.8 0.8 filler Inc. [% by wt.] (ii) Polymer beads Expancel ® Akzo Nobel — — — 920 DE 80 CAS RN 38742-70-0 1% sodium (iv) Sodium alginate; Applichem 46.7 45.0 45.0 alginate CAS: 9005-38-3 solution [% by wt.] Dispersion (iv) Sokalan ® FT CP5 BASF 1.9 1.9 1.9 solution in water (1.2) [% by wt.] Water 14.3 12.3 13.3 [% by wt.] Resulting composite particles of the invention C27 C29 C30 Resulting bulk density [g/L], based on grain sizes 0-1.5 mm 360 460 415

(47) Further details of the ingredients in table 1a and 1b (see above for the respective methods of determining the parameters): Kaolin Satintone® W: “Whitetex”, bulk density 500 g/L; D50=1.4 μm (manufacturer's figure) Bentonit Volclay®: bulk density 800-950 g/L; D50=4 μm (manufacturer's figure) Albit 45: D50=7 μm; whiteness R457 91.9% (manufacturer's figures) Poraver flour (glass flour): D50=45 μm (manufacturer's figure) Flat glass flour DIN 100: from ground flat glass shards, bulk density 1.2 g/L; whiteness R457 89%. The identifier “DIN 100” means that the flat glass flour is in the ground state, and the sieving of a sample of this constituent with an analytical sieve having a nominal mesh size of 100 μm (to DIN ISO 3310-1:2001-09) leaves a residue in the range from 1% to 10% by weight, based on the amount of sample used. Borosilicate glass beads: Product name: “3M Glass Bubbles K1”; bulk density of 125 g/L Polymer beads PM 6550 Sphere One Extendospheres®, bulk density of 50 g/L; grain size: 10-200 μm Polymer beads Expancel® 920 DE 80: bulk density of 27-33 g/L; D50=55-85 μm (manufacturer's figure)

(48) (a2) Solidifying the Solidifiable Liquid

(49) The diluted suspension was introduced in each case into plastic syringes and clamped into a syringe pump (LA-30 type). The feed rate was 12 to 15 mL/min. The diluted suspension in the syringes was then forced through a vibration nozzle, such that the diluted suspension dripped out of the vibration nozzle in uniform droplets. The droplets that dripped out of the vibration nozzle fell into an about 2% aqueous calcium chloride solution (CaCl.sub.2), product name “Calcium Chloride 2-hydrate powder for analysis ACS” from Applichem, CAS No. 10035-04-8, 2% by weight based on the total mass of the calcium chloride solution) and solidified, such that they hardened to give hardened droplets and the “sheet silicates or clays”, the “nonrefractory solids”, the “pyrolyzable fillers” and the “lightweight fillers” (according to table 1a or 1b) were encapsulated in the solidifying mixture (consisting of the 1% sodium alginate solution and the dispersion solution).

(50) Note: The size of the hardened droplets was dependent on the composition of the diluted suspension, the delivery rate of the pump and the vibration frequency of the nozzle.

(51) (a3) Treating the Hardened Droplets

(52) Subsequently, the hardened droplets were skimmed off and washed in water.

(53) Thereafter, the washed and hardened droplets were dried in a drying cabinet at 180° C. for 40 min. After the drying, the hardened droplets were free-flowing.

(54) Thereafter, the free-flowing hardened droplets were heated in a preheated muffle furnace at 950° C. for 30 minutes. The cooling resulted in composite particles produced in accordance with the invention with the bulk densities reported in table 1a or 1b.

(55) The composite particles produced in this way are excellent insulation materials of excellent suitability as intermediates for production of insulating products for the construction materials industry.

(56) As can be inferred from the last line of tables 1a and 1b, the measured bulk densities of the composite particles of the invention produced are below 500 g/L. By a suitable choice of the sheet silicates or clays, the nonrefractory solids and the density-reducing substances, it is possible to reduce the bulk density of resultant composite particles of the invention even down to below 350 g/L (cf. composite particles C19 in table 1a).

Example 2: Determination of Alkali Stability

(57) The alkali stabilities of composite particles produced in accordance with the invention as per example 1 and of prior art comparative materials of inorganic fillers or insulation materials were determined by the above-specified determination method No. 7. The results of these determinations are listed in table 2. Inventive composite particles “019” (cf. table 1a) were used.

(58) Comparative materials used were the following commercial materials: Liaver® expanded glass sintered, bulk density 250 g/L, grain size 0.5-1.0 mm Forayer® foamed glass, bulk density 270 g/L, grain size 0.5-1.0 mm Aerosilex® foamed glass (glass and siliceous earth), bulk density 125 g/L, grain size 0.5-1.0 mm

(59) TABLE-US-00003 TABLE 2 Determination of alkali stabilities of composite particles of the invention and comparative materials Sample Loss of mass [%] C19 composite particles of the invention 6 Liaver ® comparative material 7 Poraver ® comparative material 10 Aerosilex ® comparative material 100

(60) It can be seen from the results in table 2 that the composite particles of the invention examined had the highest alkali resistance (the lowest loss of mass) of all samples of inorganic fillers examined.

Example 3: Determination of Water Absorption Capacity

(61) Water absorption capacities of composite particles produced in accordance with the invention as per example 1 and of prior art comparative materials of inorganic fillers or insulation materials were determined by the above-specified determination method No. 3. The results of these determinations are listed in table 3. Inventive composite particles “C19” (cf. table 1a) were used.

(62) Comparative materials used were the commercial materials Liaver® expanded glass and Forayer® foamed glass specified above in example 2.

(63) TABLE-US-00004 TABLE 3 Determination of water absorption capacities of composite particles of the invention and comparative materials Sample Water absorption [mL/g] C19 composite particles of the invention 1.5 Liaver ® comparative material 1.5 Poraver ® comparative material 1.5

(64) It can be seen from the results in table 3 that the composite particles of the invention examined show a water absorption capacity in the region of the expanded and foamed glasses having low water absorption capacity.

Example 4: Determination of Softening Temperatures

(65) The softening temperature of each of the composite particles produced in accordance with the invention as per example 1 and of prior art comparative materials of inorganic fillers or insulation materials was determined by the above-specified determination method No. 9.

(66) The results of these determinations are listed in table 4. Inventive composite particles “C19” (cf. table 1a) were used.

(67) Comparative materials used were the commercial materials Liaver® expanded glass and Forayer® foamed glass specified above in example 2.

(68) TABLE-US-00005 TABLE 4 Determination of softening temperature in inventive composite particles produced and comparative materials C19 composite Liaver ® Poraver ® particles of the comparative comparative Measurement invention material material Softening 1250 741 753 temperature [° C.]

(69) It can be seen from the results in table 4 that the the composite particles produced in accordance with the invention that have been examined have a much higher softening temperature than the samples of prior art comparative materials of inorganic fillers or insulation materials that have been examined. This suggests significantly better thermal stability of the composite particles produced in accordance with the invention compared to the commercial inorganic fillers or insulation materials examined.

(70) The results of the determination of softening temperatures are also shown in graph form in FIGS. 2 to 7. For this purpose, the samples to be examined in each case were crushed with a mortar and pestle to give powders and mixed with a little ethanol. By means of a compression mold, cubes were then pressed from the samples thus prepared, which were examined as specified above by means of heating microscopy. The changes in shape of samples during the heating operation were recorded by photography in each case.

(71) The invention is summarized in aspects 1 to 31 specified below:

(72) 1. A process for producing an insulating product for the construction materials industry or an insulating material as intermediate for production of such a product, having the following steps:

(73) (a) producing composite particles having a grain size of less than 10 mm, preferably less than 2 mm, determined by sieving, in a matrix encapsulation process having the following steps: (a1) producing droplets of a suspension composed of at least the following starting materials: as dispersed phases (i) one or more substances selected from the group consisting of sheet silicates and clays, (ii) additionally one or more density-reducing substances selected from the group consisting of lightweight fillers having a respective bulk density in the range from 10 to 350 g/L, blowing agents and pyrolyzable fillers and (iii) one or more nonrefractory solids for reducing the melting point of the composite particles in addition to constituents (i) and (ii), and as continuous phase (iv) a solidifiable liquid, (a2) solidifying the solidifiable liquid, such that the droplets harden to give hardened droplets, and the (i) substance(s) selected from the group consisting of sheet silicates and clays, the (ii) density-reducing substance(s) and

(74) the (iii) nonrefractory solid(s)

(75) are encapsulated in the solidifying continuous phase,

(76) (a3) treating the hardened droplets so as to result in said composite particles, the treating comprising a sintering of the hardened droplets.

(77) 2. The process according to aspect 1, wherein the one or more nonrefractory solids for reducing the melting point of the composite particles that are used as additional starting material (iii) are inorganic materials

(78) selected from the group consisting of amorphous oxides, amorphous silicates, crystalline oxides and crystalline silicates and mixtures thereof, preferably selected from the group consisting of amorphous silicates and crystalline silicates,

(79) and/or (preferably “and”)

(80) having a melting point or softening temperature lower than 1350° C.

(81) 3. The process according to either of the preceding aspects, wherein the one or more nonrefractory solids for reducing the melting point of the composite particles that are used as additional starting material (iii) are selected from the group consisting of glass flours, feldspar, boric acid and boron salts such as sodium tetraborate and sodium perborate,

(82) where the one nonrefractory solid or at least one of the multiple nonrefractory solids for reducing the melting point of the composite particles is preferably selected from the group consisting of glass flours and albite,

(83) more preferably

(84) selected from the group consisting of the glass flours having a whiteness >80

(85) and/or

(86) selected from the group of the recycled glass flours.

(87) 4. The process according to any of the preceding aspects, wherein the coloring agent used for white color in step (a1)

(88) in constituent (i) is one or more substances selected from the group consisting of sheet silicates and clays,

(89) and/or

(90) in constituent (iii) is one or more nonrefractory solids for reducing the melting point of the composite particles, preferably glass flours and/or albite,

(91) and/or

(92) an additional constituent used is one or more additional starting materials, preferably selected from the group of the refractory solids, more preferably selected from the group consisting of titanium dioxide, cristobalite, aluminum oxide.

(93) 5. The process according to any of the preceding aspects, wherein

(94) in step (a1) droplets are provided by means of one or more nozzles, preferably vibration nozzles,

(95) and/or

(96) in step (a2) the solidifying of the solidifiable liquid is induced by cooling, drying or chemical reaction.

(97) 6. The process according to either of the preceding aspects, wherein the solidifiable liquid used in step (a1) is a liquid solidifiable by chemical reaction and the solidifying of the solidifiable liquid in step (a2) is induced by chemical reaction.

(98) 7. The process according to any of the preceding aspects, wherein the solidifiable liquid is a liquid solidifiable by cation exchange reaction, preferably a liquid solidifiable by reaction with calcium ions and/or barium ions and/or manganese ions, preferably by reaction with calcium ions.

(99) 8. The process according to any of the preceding aspects, wherein the solidifiable liquid is a liquid solidifiable by reaction with calcium ions,

(100) comprising one or more binders selected from the group consisting of alginate, PVA, chitosan and sulfoxyethyl cellulose,

(101) and/or

(102) an aqueous solution,

(103) wherein the solidifiable liquid is preferably an aqueous alginate solution.

(104) 9. The process according to any of the preceding aspects, wherein

(105) the or at least one of the lightweight fillers used in step (a) as density-reducing substance of component (ii), preferably having a grain size of less than 0.4 mm, more preferably less than 0.3 mm, most preferably less than 0.2 mm, determined by sieving, is selected from the group consisting of:

(106) inorganic hollow beads, preferably of borosilicate glass, organic hollow beads, particles of porous and/or foamed material, rice husk ash, core-shell particles and calcined kieselguhr

(107) and/or

(108) wherein the or at least one of the blowing agents used in step (a) as component (ii) is selected from the group consisting of: carbonates, hydrogencarbonates and oxalates vegetable flours, preferably selected from the group consisting of coconut shell flour, walnut shell flour, grape seed flour, olive kernel flour, wheat flour, corn flour, wood flour, sunflower husk flour and cork flour, starch, potato dextrin, sugars, plant seeds,

(109) and rice husk ash,

(110) and/or

(111) wherein the or at least one of the pyrolyzable fillers used in step (a) as component (ii) is selected from the group consisting of: polymer beads

(112) and styrofoam beads.

(113) 10. The process according to any of the preceding aspects, wherein one or more refractory solids are used in step (a1) as additional starting material for production of a further dispersed phase, preferably in a proportion of not more than 10% by weight, based on the total amount of the solid constituents of the suspension produced in step (a1), wherein the or at least one of the refractory solids used additionally in step (a1) is preferably selected from the group consisting of:  oxides of one or more elements from the group consisting of Si, Al, Zr, Ti, Mg and Ca,

(114) and  mixed oxides each comprising one or more elements from the group consisting of Si, Al, Zr, Ti, Mg and Ca,

(115) wherein the proportion of the total amount of the constituents from this group is preferably not more than 10% by weight, based on the total amount of the solid constituents of the suspension produced in step (a1), wherein the or at least one of the refractory solids used additionally in step (a1) is preferably selected from the group consisting of: aluminum oxide, zirconium oxide, titanium dioxide, silicon dioxide, magnesium oxide, calcium oxide, calcium silicate, sheet silicates, preferably mica, aluminum silicates, and magnesium aluminum silicate, preferably cordierite,

(116) wherein the proportion of the total amount of the constituents from this group is preferably not more than 10% by weight, based on the total amount of the solid constituents of the suspension produced in step (a1).

(117) 11. The process according to any of the preceding aspects, wherein the or at least one of the substance(s) used in step (a1) as substance of component (i)

(118) is selected from the group consisting of sheet silicates and clays that do not melt in an incongruent manner below 1500° C.

(119) and/or

(120) is selected from the group consisting of the sheet silicates kaolinite, montmorillonite and illite,

(121) and the clays kaolin and bentonite.

(122) 12. The process according to any of the preceding aspects, wherein the treating in step (a3) is conducted in such a way that the bulk density of the resultant composite particles in step (a3) is lower than the bulk density of the hardened droplets in the dried state

(123) and/or

(124) said resultant composite particles in step (a3) have a bulk density <500 g/L, preferably <400 g/L, more preferably <300 g/L.

(125) 13. The process according to any of the preceding aspects, wherein all or some of the resultant composite particles in step (a3) have a grain size of <1.5 mm, preferably at least some have a grain size in the range from 0.1 mm to 0.5 mm and more preferably at least some have a grain size in the range from 0.1 mm to 0.3 mm, determined by sieving.

(126) 14. The process according to any of the preceding aspects, wherein component (ii) comprises, as density-reducing substance(s),

(127) one or more blowing agents and the treating in step (a3) is conducted in such a way that the one or more blowing agents expand and hence form cavities in the resultant composite particle

(128) and/or

(129) one or more pyrolyzable fillers and the treating in step (a3) is conducted in such a way that the one or more pyrolyzable fillers pyrolyze and hence form cavities in the resultant composite particle.

(130) 15. The process according to any of the preceding aspects, wherein component (i) in step (a1) comprises at least one clay, preferably containing kaolinite and/or illite,

(131) and/or

(132) wherein the treating in step (a3) comprises sintering at a temperature in the range from 900 to 980° C., preferably forming a sintered composite comprising components (i), (ii) and (iii).

(133) 16. The process according to any of the preceding aspects, wherein the sintering in step (a3) does not exceed a temperature of 1000° C.

(134) 17. The process according to any of the preceding aspects, wherein the hardened droplets are sintered in step (a3) so as to result in solid particles as intermediate, and wherein the surface of these solid particles is subsequently sealed, preferably by means of an organic coating composition, so as to result in said composite particles.

(135) 18. The process according to any of the preceding aspects, wherein the resultant composite particles in step (a3) are characterized by

(136) (A) a whiteness W≥65, preferably W≥80, more preferably W≥90,

(137) and/or

(138) (B) a thermal conductivity value at room temperature (20° C.) γR of ≤0.26 W/m*K, preferably ≤0.10 W/m*K, more preferably ≤0.07 W/m*K,

(139) and/or

(140) (C) an alkali stability, determined as the weight loss in the course of storage in sodium hydroxide solution at pH 14 for 30 days, of ≤9% by mass, preferably ≤8% by mass, more preferably ≤7% by mass, based on composite particles having a grain size in the range of 0.5-1.0 mm,

(141) and/or

(142) (D) a grain strength ≥1.5 N/mm2, preferably ≥2.0 N/mm2, more preferably ≥4.0 N/mm2, determined to DIN EN 13055-1:2008-08, Annex A (Method 1, agitating for 2*30 s with amplitude 0.5), at a grain size in the range of 0.25-0.5 mm,

(143) and/or

(144) (E) a water absorption capacity, determined via water absorption according to Enslin, of ≤2.5 mL/g, preferably ≤2.0 mL/g and more preferably ≤1.7 mL/g,

(145) and/or

(146) (F) a water solubility, determined as the weight loss in the course of storage in distilled water for 30 days, of ≤2% by mass, preferably ≤1% by mass, more preferably ≤0.2% by mass, based on composite particles having a grain size in the range of 0.5 to 1.0 mm, and/or

(147) (G) a softening temperature 900° C., preferably 1000° C., more preferably 1200° C., determined by heating microscopy.

(148) 19. The use of a matrix encapsulation method, preferably using a nozzle, more preferably using a vibrating nozzle, for production of composite particles having a bulk density of <500 g/L, preferably <400 g/L, more preferably <300 g/L, in the production of an insulating product for the construction materials industry or an insulating material as intermediate for production of such a product.

(149) 20. The use of composite particles producible by means of a matrix encapsulation method as intermediate for production of an insulating product for the construction materials industry or as part of an insulating product for the construction materials industry,

(150) 21. The use according to aspect 20, wherein the composite particles are sealed composite particles, each consisting of a composite particle producible by means of a matrix encapsulation method and a shell of an organic coating composition that surrounds and seals the composite particle,

(151) 22. The use according to any of aspects 19 to 21, wherein the intermediate for production of an insulating product for the construction materials industry or the insulating product for the construction materials industry is used in indoor and outdoor wall and roof linings, indoor and outdoor thick-layer render systems, thin-layer systems and in resin systems for the construction materials industry.

(152) 23. An insulating product for the construction materials industry or insulating material for production of such a product, comprising a number of composite particles having a grain size of less than 10 mm, comprising sintered composite of particles of one or more nonrefractory solids, particles of one or more substances selected from the group consisting of sheet silicates and clays that have been embedded into the sintered composite,

(153) wherein the insulating product for the construction materials industry or the insulating material for production of such a product is producible by a process according to any of aspects 1 to 18

(154) and/or the composite particles are characterized by

(155) (D) a grain strength 1.5 N/mm2, preferably ≥2.0 N/mm2, more preferably ≥4.0 N/mm2, determined to DIN EN 13055-1:2008-08, Annex A (Method 1, agitating for 2*30 s with amplitude 0.5), at a grain size in the range of 0.25-0.5 mm,

(156) and

(157) (E) a water absorption capacity, determined via water absorption according to Enslin, of ≤2.5 mL/g, preferably ≤2.0 mL/g and more preferably ≤1.7 mL/g.

(158) 24. The insulating product for the construction materials industry or insulating material for production of such a product according to aspect 23,

(159) wherein the composite particles are additionally characterized by

(160) (A) a whiteness W≥65, preferably W≥80, more preferably W≥90.

(161) 25. The insulating product for the construction materials industry or insulating material for production of such a product according to aspect 23 or 24,

(162) wherein the composite particles are additionally characterized by

(163) (B) a thermal conductivity value at room temperature (20° C.) γR of ≤0.26 W/m*K, preferably ≤0.10 W/m*K, more preferably ≤0.07 W/m*K,

(164) and/or

(165) (C) an alkali stability, determined as the weight loss in the course of storage in sodium hydroxide solution at pH 14 for 30 days, of ≤9% by mass, preferably ≤8% by mass, more preferably ≤7% by mass, based on composite particles having a grain size in the range of 0.5-1.0 mm,

(166) and/or

(167) (F) a water solubility, determined as the weight loss in the course of storage in distilled water for 30 days, of ≤2% by mass, preferably ≤1% by mass, more preferably ≤0.2% by mass, based on composite particles having a grain size in the range of 0.5 to 1.0 mm,

(168) and/or

(169) (G) a softening temperature 900° C., preferably 1000° C., more preferably 1200° C., determined by heating microscopy.

(170) 26. The insulating product for the construction materials industry or insulating material for production of such a product according to any of aspects 23 to 25, wherein

(171) in the sintered composite of particles of one or more nonrefractory solids the one nonrefractory solid or at least one of the multiple nonrefractory solids

(172) is selected from the group consisting of amorphous oxides, amorphous silicates, crystalline oxides and crystalline silicates and mixtures thereof, preferably selected from the group consisting of amorphous silicates and crystalline silicates,

(173) and/or

(174) has a melting point or softening temperature lower than 1350° C.

(175) 27. The insulating product for the construction materials industry or insulating material for production of such a product according to any of aspects 23 to 26, wherein

(176) in the sintered composite of particles of one or more nonrefractory solids the one nonrefractory solid or at least one of the multiple nonrefractory solids

(177) is selected from the group consisting of glass flours, feldspar, boric acid and boron salts, such as sodium tetraborate and sodium perborate,

(178) where the one nonrefractory solid or at least one of the multiple nonrefractory solids is preferably selected from the group consisting of glass flours and albite,

(179) more preferably

(180) selected from the group consisting of the glass flours having a whiteness >80

(181) and/or

(182) selected from the group of the recycled glass flours.

(183) 28. The insulating product for the construction materials industry or insulating material for production of such a product according to any of aspects 23 to 27, wherein the composite particles comprise as coloring agent for white color one or more substances selected from the group consisting of sheet silicates and clays as particles embedded into the sintered composite

(184) and/or one or more nonrefractory solids, preferably albite, as a constituent of the sintered composite,

(185) and/or as additional constituent one or more additional starting materials, preferably selected from the group of the refractory solids, more preferably selected from the group consisting of titanium dioxide, cristobalite and aluminum oxide.

(186) 29. The insulating product for the construction materials industry or insulating material for production of such a product according to any of aspects 23 to 28,

(187) comprising, as lightweight fillers, organic hollow beads that have been embedded into the sintered composite and have a grain size of less than 0.4 mm, more preferably less than 0.3 mm, most preferably less than 0.2 mm, determined by sieving,

(188) 30. The insulating product for the construction materials industry or insulating material for production of such a product according to any of aspects 23 to 29, comprising particles of one or more substances selected from the group consisting of sheet silicates and clays that have been embedded into the sintered composite,

(189) that do not melt in a congruent manner below 1500° C.

(190) and/or

(191) are selected from the group consisting of the sheet silicates kaolinite, montmorillonite and illite,

(192) and the clays kaolin and bentonite.

(193) 31. The insulating product for the construction materials industry or insulation material for production of such a product according to any of aspects 23 to 30, comprising a number of composite particles having a grain size of <1.5 mm, preferably a grain size in the range from 0.1 mm to 0.5 mm, more preferably a grain size in the range from 0.1 mm to 0.3 mm, determined by sieving.