U.S. patent application number 10/886432 was filed with the patent office on 2005-01-06 for process for producing colouring pigment granulated materials.
This patent application is currently assigned to Rhein-Chemotechnik GmbH Gesellschaft Fur Chemisch-Technische Erzeugnisse. Invention is credited to Herrmann, Bernd, Noack, Bernd.
Application Number | 20050003084 10/886432 |
Document ID | / |
Family ID | 7926398 |
Filed Date | 2005-01-06 |
United States Patent
Application |
20050003084 |
Kind Code |
A1 |
Noack, Bernd ; et
al. |
January 6, 2005 |
Process for producing colouring pigment granulated materials
Abstract
A process for producing coloring pigment granulated materials
comprises producing binder-free granulated materials via a primary
granulator, immediately compacting the granulated materials,
feeding the compacted granulated materials to a classification that
separates a useful grain size fraction, and coating the useful
grain size fraction with a coating material.
Inventors: |
Noack, Bernd; (Saalfeld,
DE) ; Herrmann, Bernd; (Schleiz, DE) |
Correspondence
Address: |
WILLIAM COLLARD
COLLARD & ROE, P.C.
1077 NORTHERN BOULEVARD
ROSLYN
NY
11576
US
|
Assignee: |
Rhein-Chemotechnik GmbH
Gesellschaft Fur Chemisch-Technische Erzeugnisse
|
Family ID: |
7926398 |
Appl. No.: |
10/886432 |
Filed: |
July 7, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10886432 |
Jul 7, 2004 |
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10030925 |
Jan 4, 2002 |
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10030925 |
Jan 4, 2002 |
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PCT/DE00/03690 |
Oct 20, 2000 |
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Current U.S.
Class: |
427/212 ;
427/421.1 |
Current CPC
Class: |
C04B 18/02 20130101;
Y10T 428/2993 20150115; Y10T 428/2996 20150115; Y10T 428/2995
20150115; C04B 20/1018 20130101; C04B 2103/54 20130101; C04B
20/1055 20130101; Y10T 428/2991 20150115; C04B 2103/54 20130101;
C04B 18/02 20130101; C04B 18/02 20130101; Y10T 428/30 20150115;
Y10T 428/2998 20150115 |
Class at
Publication: |
427/212 ;
427/421.1 |
International
Class: |
B05D 007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 21, 1999 |
DE |
199 50 712.0 |
Claims
What is claimed is:
1. A process for producing colouring pigment granulated materials,
comprising: producing binder-free granulated materials via a
primary granulator, compacting said granulated materials
immediately after said step of producing; feeding said compacted
granulated materials to a classification that separates a useful
grain size fraction; and coating said useful grain size fraction
with a coating material.
2. The process as claimed in claim 1, wherein the coating material
is applied to the fraction in a dissolved form using spray nozzles,
and the coating is solidified by feeding in dry air.
3. The process as claimed in claim 1, wherein the coating is made
of a molten material that is applied to the useful fraction at a
fusion temperature of >60.degree. C. using spray nozzles, and
wherein the coating is solidified by cooling.
4. The process as claimed in claim 1, wherein granulation water
contained in the granulated material is expelled by a drying
process.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a divisional of U.S. patent application Ser. No.
10/030,925, filed on Jan. 4, 2002, which is a 371 of PCT/DE00/03690
filed on Oct. 20, 2000, which claims priority under 35 U.S.C. 119
of German Patent Application No. 199 50 712.0, filed on Oct. 21,
1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to colouring pigment granulated
materials for the colouring of building material, especially for
the colouring of concrete, and to a process for producing colouring
pigment granulated materials.
[0004] 2. The Prior Art
[0005] Usually, colouring powders for concrete colours are
granulated to obtain good dosing and transport properties, and to
reduce the formation of dust. Different granulated materials for
the colouring of concrete are known from Background Art, with the
granulated materials being made from a largely homogeneous mixture
of colouring powder and a binder to obtain a sufficient granulated
material strength. The drawback of these disclosed granulated
materials is the low dissolution speed caused by a largely
homogeneous binder distribution. Until now, an increase in
dissolution speed was obtained, e.g., by reducing granulated
material size, while this led to an increased formation of dust
during transportation and processing.
[0006] In addition, this requires the admixture of dispersing and
surface-active agents to the granulated material.
[0007] DE 196 38 042 A1 describes a process to produce inorganic
pressed or briquette granulated materials from inorganic pigments
using auxiliaries, in which one or more pigments are mixed with one
or more auxiliaries improving the working properties, this mix is
subjected to a pressing or briquetting step, this pressed or
briquetted product is comminuted, the comminuted product is
separated into two or more fractions, the fraction in which at
least 85% of the particles are bigger than 80 .mu.m, and preferably
bigger than 100 .mu.m, or are between 80 and 2000 .mu.m, and
preferably between 100 and 1000 .mu.m, are withdrawn as a product
and are rounded in an additional step if any, while the other
fraction or fractions exit the process or are recirculated into the
process.
[0008] EP 0 191 278 disclosed a colour preparation for the
colouring of building material using inorganic metal oxides, and
consisting of a pourable damp granulated material. The latter
document also provides for a powder which is to be scattered on the
granulate as a separating agent to keep the granulate pourable even
in large containers, so that the granulate only needs to be dried
in part. The drawback of this is the fact that a homogenous
distribution of the separating agent is not guaranteed in this
mixture of damp granulated material and separating agent, and that
flowability is restricted due to the granulated material's
shape.
[0009] Furthermore, DE 39 18 694 C 1 and DE 41 03 531 A 1 disclosed
processes to produce spray granulates using previously mixed in
inorganic binders. According to DE 41 03 531 A 1, it is possible in
this context to bond fine particles to the cores using an
additional build-up granulation. A drawback of both processes is
the high consumption of drying energy.
[0010] In the process described in DE 39 18 694 C 1, a pigment
suspension is sprayed in drop shape, and dried to obtain pigment
micro granulates in a flow of hot gas. The suspension is pulverized
using a centrifugal atomizer, a pressure nozzle, or a two-component
nozzle. The stability of the granulated materials is achieved by
inorganic binders blended into the aqueous pigment oxide suspension
beforehand. The drawback of this is the high dust content, and the
bad flow behaviour.
[0011] Another disadvantage is the fact that pigment oxides of the
granulated materials are mixed with inorganic binders which should
guarantee stability during transportation and storage.
[0012] Although the process proposed in DE 41 035 31 A 1 also
provides for spraying with aqueous solutions of inorganic binders
during a subsequent granulation, this rather corresponds to a
bonding of fine particles to the granulate core, and thus to a
granulation of the dust particles in the mix. This can also form an
external shell of particles and binders exposed to abrasion on the
granulate core.
[0013] According to a process described in DE 197 31 698 A 1,
pressed granulates are produced essentially by applying line forces
of >15 kN/cm, and they are comminuted in general, and rounded if
necessary. As in DE 196 38 042 A 1, the pigment powder is mixed
with binders too. Surface-active and/or blasting agents are also
introduced into the mix to dissolve adherence at a later time. It
cannot be excluded in this context that such substances have
adverse effects on the properties of the coloured building
materials.
SUMMARY OF THE INVENTION
[0014] It is the object of the invention to provide a granulate and
a process for the economic production of this granulate, which is
able to liberate itself at a high speed after its addition to a
building material to be coloured.
[0015] In the invention, the granulated materials consist of a core
without binder and of a shell. The shell adapts to the surface of
the granulated material, enclosing it completely, and generating
mechanical strength. No binders, emulsifying agents, surface-active
agents, dispersing agents, and preservatives are mixed into the
pigment oxide powder, while a pigment-water mixture is produced and
granulated. In contrast to the auxiliaries used according to
Background Art, the use of water presents the advantage that it can
be expelled again during the process. The physical properties of
the granulated materials, such as transport and storage stability,
are brought about by the shell characteristics, so that they are
reproducible and stable. An advantage for the manufacture of the
granulated materials is the opportunity to separate useful and
recycling grain sizes.
[0016] The granulate material cores have a grain size of preferably
0.1 through 8 mm. The coating layer is preferably made of a
destructible material, and the granulated material preferably
presents a moisture content of <30%. In an especially preferred
embodiment, the granulated materials have a grain size of 0.5
through 1.5 mm and a moisture content of <5%.
[0017] In another preferred embodiment, the coating layer consists
of organic matter, or a mixture of inorganic and organic
matter.
[0018] It is also possible to use the process according to the
invention to produce binder-free granulated materials, and to coat
them with a melting by spray deposition. The coating material must
have a fusion temperature of >60.degree. C., and it may consist,
e.g., of wax. It is an advantage in this context to obtain the
hardening of the shell by cooling it down using an air flow at a
regulable temperature.
[0019] At the time of transportation, the granulate according to
the invention will have a solid shell with an approximately uniform
nature and thickness. By classifying the grain size, and creating a
coating by drying the granulate if necessary, it is possible to
adjust compaction weight, remaining humidity, shell thickness and
grain size, thus adapting these values to the conditions desired in
the corresponding case. The granulate according to the invention is
characterized by a high compatibility with building materials.
[0020] By arranging a shell around the granulated material cores,
the colouring pigment will be present without any fixed bond in the
building material after adding the granulate and destroying the
shell, so that the disagglomeration of the granulated materials
will proceed at a very high speed because, as no binders were used
in the granulate material core, the granulated materials will only
present a very low adhesive force there. The high dissolving power
of the coated granulated materials allows the use of granulated
materials with higher grain diameters. Other advantages include the
low content of foreign matter in the colouring pigments of the
coated granulated materials, and the universal applicability of the
process according to the invention to produce the coating for all
granulation processes disclosed so far such as, e.g., press
granulation, fluid-bed granulation, spray granulation, or build-up
granulation.
BRIEF DESCRIPTION OF THE DRAWING
[0021] Other objects and features of the present invention will
become apparent from the following detailed description considered
in connection with the accompanying drawing. It is to be
understood, however, that the drawing is designed as an
illustration only and not as a definition of the limits of the
invention.
[0022] FIG. 1 is a diagrammatic view of the process used to produce
coated granulated materials.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] As shown in FIG. 1, powdered colouring pigments are
withdrawn from a colouring pigment hopper 1 using a dosing device,
and fed to a compulsory mixer. In this compulsory mixer 2, water is
added at a proportion of between 10% and 30% to form granulated
materials. The discharge of the mixer 2 is fed to a primary
granulator 3 which produces a primary granulate in the desired
grain size. This primary granulate is fed to a pelletizer disk 4
and compacted. A modifiable disk setting ensures that a useful
grain size of 0.5 mm to 1.5 mm is produced predominantly. The
discharge of disk 4 is fed to a shaking screen 5 on which oversize
particles with a grain size of more than 1.5 mm are separated. The
useful grain size fraction of 0.5 to 1.5 mm separated by the
shaking screen 5 is fed to a continuously working drum 6 in which
spray nozzles 6.1 are used to add polyvinyl alcohol in an aqueous
suspension, forming a coating material which is liquid at first. In
drum 6, continuous dry air 6.3 is fed in the area of a drying zone
6.2, thus reducing the water content of the sprayed granulated
materials to a value of less than 0.5%, and obtaining the
solidification of the coating material. By the dry air 6.3, fine
size portions of the colouring pigment material in drum 6 are
picked up, separated in a dust removal plant 8, and fed to the
mixer 2. The discharge of drum 6 is fed to and stored in the
finished material bin 7 as coated coloured granulates.
[0024] Accordingly, while only a few embodiments of the present
invention have been shown and described, it is obvious that many
changes and modifications may be made thereunto without departing
from the spirit and scope of the invention.
List of Reference Signs
[0025] 1 Colouring pigment hopper
[0026] 2 Mixer
[0027] 3 Primary granulator
[0028] 4 Pelletizer disk
[0029] 5 Shaking screen
[0030] 6 Drum
[0031] 6.1 Spray nozzles
[0032] 6.2 Drying zone
[0033] 6.3 Dry air
[0034] 7 Finished material bin
[0035] 8 Dust removal
* * * * *