Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/50—Mixing liquids with solids
  • B01F23/56—Mixing liquids with solids by introducing solids in liquids, e.g. dispersing or dissolving
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/45—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads
  • B01F25/452—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces
  • B01F25/4521—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube
  • B01F25/45212—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube the elements comprising means for adjusting the orifices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
  • B05B7/00—Spraying apparatus for discharge of liquids or other fluent materials from two or more sources, e.g. of liquid and air, of powder and gas
  • B05B7/02—Spray pistols; Apparatus for discharge
  • B05B7/04—Spray pistols; Apparatus for discharge with arrangements for mixing liquids or other fluent materials before discharge
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/45—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/45—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads
  • B01F25/452—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces
  • B01F25/4521—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube
  • B01F25/45211—Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads characterised by elements provided with orifices or interstitial spaces the components being pressed through orifices in elements, e.g. flat plates or cylinders, which obstruct the whole diameter of the tube the elements being cylinders or cones which obstruct the whole diameter of the tube, the flow changing from axial in radial and again in axial
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/40—Static mixers
  • B01F25/46—Homogenising or emulsifying nozzles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/06—Mixing of food ingredients
  • B01F2101/07—Mixing ingredients into milk or cream, e.g. aerating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/06—Mixing of food ingredients
  • B01F2101/14—Mixing of ingredients for non-alcoholic beverages; Dissolving sugar in water
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/21—Mixing of ingredients for cosmetic or perfume compositions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/22—Mixing of ingredients for pharmaceutical or medical compositions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/2805—Mixing plastics, polymer material ingredients, monomers or oligomers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/30—Mixing paints or paint ingredients, e.g. pigments, dyes, colours, lacquers or enamel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/40—Mixing liquids with liquids; Emulsifying
  • B01F23/41—Emulsifying
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/4238—With cleaner, lubrication added to fluid or liquid sealing at valve interface
  • Y10T137/4358—Liquid supplied at valve interface
  • Y10T137/4442—External pressure
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/4238—With cleaner, lubrication added to fluid or liquid sealing at valve interface
  • Y10T137/4358—Liquid supplied at valve interface
  • Y10T137/4449—Gravity or capillary feed
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/6851—With casing, support, protector or static constructional installations
  • Y10T137/7036—Jacketed
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8593—Systems
  • Y10T137/86493—Multi-way valve unit
  • Y10T137/86718—Dividing into parallel flow paths with recombining
  • Y10T137/86759—Reciprocating
  • Y10T137/86791—Piston

Definitions

• the invention relates to a dispersing nozzle with a variable throughput, in particular with a continuously variable throughput.
• a painting system and a spray gun with this dispersing nozzle is described.
• the dispersing device is based on the principle of a jet disperser and consists of at least one inlet for the material to be dispersed, a chamber with a multiplicity of openings or slots arranged in rows along the chamber wall, which open into an outlet chamber, and with an outlet for the finished one Dispersed material, a piston being displaceably arranged in the chamber which, depending on its position in the chamber, partially or completely shuts off a certain number of openings or slots for the passage of the flow of dispersed material.
• a number of different dispersing devices have become known for mixing and dispersing different compositions, for example of oil-water emulsions, which have the common principle of absorbing energy in a dispersing gap or in appropriately shaped bores in the devices.
• the dispersed material is usually under increased pressure by the
• 2-component polyurethane paints (2-component PUR paints) are only mixed shortly before application. Depending on the reactivity of the coating systems, this pot life can range from several minutes to hours. While such two-component systems were used in the past dissolved in organic solvents, a large number of water-dispersible two-component systems have recently been developed.
• the water-dispersible two-component systems regularly consist of a hydroxyl-containing resin component (binder, polyol) and a polyisocyanate component (hardener, crosslinker).
• the hydroxy-functional resin component is usually in the form of an aqueous dispersion
• the polyisocyanate component is in the form of an anhydrous 100% component or dissolved in a solvent.
• Such systems are known, for example, from EP-A 583 728.
• a disadvantage of these coating systems is that the coating quality known from the two-component systems based on purely organic solvents has not yet been achieved in some areas of application.
• Dispersion of the per se hydrophobic isocyanate component only takes place shortly before the lacquers are applied, since the polyisocyanate component reacts with water and therefore has only a limited storage stability in the presence of water.
• the dispersion of the per se hydrophobic polyisocyanate component in the aqueous hydroxy-functional resin dispersion by conventional static mixing devices presents considerable difficulties. The reason for this is that the isocyanate component is already stabilized during the emulsification of emulsion particles already formed on the surface, so that the superficial stabilization layer prevents further division.
• Aqueous two-component polyurethane coating emulsions therefore regularly have a bimodal particle size distribution with a first distribution maximum of a particle size that corresponds to the hydroxy-functional resin dispersion and a second distribution maximum with a particle size of above 10,000 nm (isocyanate component), with significant proportions with particle sizes of are present above 20,000 nm.
• Hydrophilized polyisocyanates and polyisocyanates containing external emulsifiers have also already been developed by chemical modification, which, although they enable significantly easier dispersion with static mixing devices to an average particle size of less than 1000 nm, result in hardened paint films with inadequate resistance properties for many areas of application.
• Paint films with good resistance properties can only be obtained by using hydrophobic polyisocyanate components.
• the European patent application EP 685 544 AI describes a process for the preparation of aqueous two-component polyurethane lacquer emulsions by mixing binder resins with polyisocyanates and water, in which the mixture is built up under a principle through a dispersing nozzle, based on the principle of a one- or multi-stage jet disperser Pressure of 1 to 30 MPa is pressed.
• special bimodal paint emulsions are created.
• a variant of the jet disperser is equipped with a large number of bores which can be covered in succession with the aid of a displaceable insert tube in order to
• the proposed design of the disperser proves to be very unfavorable, since the displaceable insert tube is fully immersed in the solution to be dispersed. As a result, it can e.g. with paint emulsions to undesirable
• the object of the invention is to develop a dispersing device which does not have the disadvantages mentioned above, and yet which, with the dispersing quality remaining the same, enables an, in particular continuous, change in the quantity throughput of dispersed material.
• a further object of the invention is therefore to provide a mixing apparatus for aqueous two-component polyurethane lacquers with a high lacquer quality, which continuously produces the same emulsion quality with fluctuating sales volumes.
• the state of the art today is spray guns, which, due to their complicated supply and mixing technology with paint systems with abrasive fillers, only have a very short service life and then have to be laboriously cleaned, so that they are practically unsuitable for fast-reacting two-component paint systems with fillers.
• the further object of the invention is therefore to enable direct processing of quickly reacting paint systems and to integrate the dispersing device in a paint spraying device (spray gun).
• the invention relates to a dispersing device with variable throughput of dispersed material based on a jet disperser, consisting at least of an inlet for the material to be dispersed, a chamber with a plurality of openings arranged in rows along the chamber wall, which open into an outlet chamber, and with a Outlet for the finished material to be dispersed, characterized in that a piston is arranged displaceably in the chamber and, depending on its position in the chamber, partially or completely blocks a certain number of openings for the passage of the flow of material to be dispersed.
• a preferred design of the dispersing device has at least two rows of openings arranged one behind the other, which are arranged axially (i.e. in the direction of the direction of movement of the piston) in the chamber wall.
• the invention also relates to a variant of the dispersing device comprising at least one inlet for the material to be dispersed, a chamber with one or more slot-shaped openings arranged along the chamber wall, which open into an outlet chamber, and with an outlet for the finished dispersed material, characterized in that that a piston is slidably arranged in the chamber, which, depending on its position in the chamber, partially or completely blocks the slots for the passage of the stream of dispersed material.
• This variant enables a continuous adjustment of the throughput of the dispersed material.
• a special embodiment of the devices is characterized in that at least one flushing hole with a larger cross section than the cross section of the openings or the slots is provided at one end of the chamber.
• the piston and the chamber have a circular cross section.
• a mixing nozzle e.g. for the polyisocyanate, with which a raw emulsion is produced by injecting the polyisocyanate into the polyol component.
• another mixing orifice Located downstream of this variant is another mixing orifice, which ensures a comparatively good quality of the raw emulsion and prevents coarse parts.
• dispersing device it is also possible, by using the dispersing device according to the invention, to considerably reduce the solvent content in the dispersion and, preferably, to dispense with hydrophilizing the polyisocyanate component.
• dispersions with a solvent content of less than 15% by weight can be readily prepared according to the invention.
• the pressure used in the dispersion the number of nozzle passages and the two-component system used, it is also possible to produce emulsions which are completely free of solvents and hydrophilizers.
• At least the piston and / or the wall of the chamber are made of ceramic or have a ceramic coating.
• Zirconium oxide or SiC is used in particular as the ceramic material. This makes it possible to process mixes containing abrasive fillers (eg SiC quartz sand) without problems over a longer period of time.
• the centerpiece of the preferred dispersing device is a ceramic sleeve with the homogenizing holes and the ceramic piston. It was found that the ceramic components had to be ground precisely to avoid leakage between the piston and the sleeve. It was found that components are made of
• the dispersing device according to the invention can be operated both from the inside out and from the outside in, i.e. that the inlet and outlet can also be interchanged without causing disadvantages in the dispersion.
• a flushing lantern can be installed to avoid a film of paint on the piston when it is at a standstill.
• the piston of the preferred device can be cleaned in a simple manner by means of a rinsing chamber which adjoins the chamber and is separate from this chamber.
• the inlet chamber may be sealed with additional ring seals from the wash cabinet.
• the piston of the device is preferably movable by means of an electric or pneumatic drive.
• pressure control for example via a pneumatic drive of the piston
• the dispersion device according to the invention can be adjusted in a fraction of a second, for example to switch on or off so many nozzles in the case of fluctuating throughput that the same homogenization pressure and thus the same emulsion quality is always ensured. If electrical stepper motors are used, adjustment in the ms range is also possible.
• Dispersing device allows.
• the device according to the invention can be used to produce two-component polyurethane lacquers of the highest quality and with a large control range.
• the geometry of the bores and slots should in particular be dimensioned such that an energy density of preferably 10 5 to 10 7 W / cm 3 , preferably 10 6 to 10 7 W / cm 3 is achieved in the dispersed material. This is achieved if so much material is removed in the area of the bore or the slots that the length of the bore is 1-3 times as long, particularly preferably 1-2 times as long, as the diameter of the
• bimodal aqueous two-component polyurethane coating emulsions based on hydroxy-functional resin dispersions and polyisocyanates are accessible which have a particle size distribution with a first distribution maximum at a particle size of less than 500 nm, preferably from 10 to 200 nm and a second distribution maximum with a particle size of 200 to 2000 nm, preferably from 300 to 1000 nm.
• the particle sizes of the distribution maxima differ in particular by a factor of 2.
• 99% by weight of the particles of such an emulsion have a particle size of less than 5000 nm, preferably less than 1000 nm.
• Suitable binder resins are e.g. Polyacrylates, polyesters, urethane-modified polyesters, polyethers, polycarbonates or polyurethanes having isocyanate-reactive groups, in particular those in the molecular weight range from 1,000 to 10,000 g / mol. Hydroxy groups are preferably used as isocyanate-reactive groups.
• the binder resins are generally used as aqueous dispersions.
• polyisocyanate component Any organic polyisocyanates with aliphatic, cycloaliphatic, araliphatic and / or aromatically bound free isocyanate groups are suitable as the polyisocyanate component.
• the polyisocyanate component should generally have a viscosity of 20 to 1,000 mPa.s, preferably below 500 mPa.s.
• higher-viscosity polyisocyanates can also be used if the viscosity of the polyisocyanate component is reduced by an appropriate solvent content.
• Particularly preferred polyisocyanates are those with exclusively aliphatic and / or cycloaliphatic isocyanate groups with an average NCO functionality between 2.2 and 5.0 and a viscosity of 50 to 500 mPa.s at 23 ° C. With a correspondingly low viscosity, dispersion according to the invention is successful with a sufficiently small particle size completely without addition of solvent. Furthermore, the usual ones known in paint chemistry
• Additives and modifiers are used.
• the field of application of the dispersing device according to the invention is not restricted to the use of component systems specially developed for water-dispersible coating systems, as described, for example, in the European publication mentioned at the beginning. Rather, it is possible to use a large number of the previously not water-dispersible two-component systems. However, when using two-component systems specially developed for dispersion in water, the amount of dispersion (ie the pressure to be applied) using the dispersion device according to the invention will be particularly favorable.
• Lacquer emulsions obtained with the dispersing device according to the invention are preferably used to produce high-quality coatings on a wide variety of substrates and materials such as wood, metals, plastics, etc. Such coating systems are preferably used for painting car bodies or body parts in original car painting.
• the dispersing device according to the invention can be used for a large number of fields of application and dispersing tasks.
• the invention also relates to the use of the dispersing device according to the invention for dispersing and mixing chemical products such as the aforementioned water-based paints, film emulsions, silicone emulsions and pharmaceutical and cosmetic products such as ointments, creams or care milk or for dispersing or homogenizing natural or food products, eg juices, mixed drinks or milk products, particularly preferably milk or cream.
• the dispersing device according to the invention also serves to regulate material flows and to carry out rapid chemical reactions.
• Another object of the invention is a painting system for the application of multi-component paint comprising at least one painting station with spraying units for the paint, feed lines and pumps for the paint components and one Mixing unit for the paint components, characterized in that the mixing unit has a dispersing device according to the invention.
• the described dispersing device according to the invention can also be used in a technically simplified and reduced-size version, for example in a spray gun for direct spraying (so-called airless spraying method) for the surface coating of large objects.
• Tanks in particular ballast tanks, ship hulls, pipes or structures, to mix two components (e.g. for two-component polyurethane paints). Only a few holes in the dispersing device are provided opposite or offset for each of the two components.
• the mixed material can then be applied directly from the outlet of the dispersing device, which is designed as a nozzle, or via an additional spray nozzle connected directly to the dispersing device.
• compressed air can also be supplied to the liquid components via the modified dispersion device by means of a separate air supply line to improve the spray pattern.
• the device is free from wear even when using abrasive fillers such as SiC or SiO 2 , 4. the simple construction, by which cleaning, which may be necessary, is considerably simplified, for example by pushing the piston in the spray gun up to the nozzle outlet,
• the invention enables the construction of a light and easy-to-handle spray gun for manual spraying, which can be used in places that are difficult to access mechanically (shipbuilding).
• a painting system is preferred in which a simple conventional nozzle mixer is connected upstream of the dispersing device.
• An additional buffer store is particularly advantageously provided between the mixing unit and the spraying units.
• FIG. 1 shows a cross section through a dispersing device according to the invention with an upstream mixing nozzle
• Figure 2 shows a cross section through a variant of the dispersing device according to
• FIG. 2a a schematic detailed illustration of the nozzle according to FIG. 2 (side view) to explain the nozzle geometry
• Figure 3 shows a cross section through a variant of the dispersing device according to
• FIG. 3a a schematic detailed illustration of the nozzle according to FIG. 3 (side view) to explain the nozzle geometry
• Figure 4 the scheme of a painting system with several according to the invention
• FIG. 5 a graph which shows the average particle size as a function of the homogenization pressure for various dispersing devices
• Figure 6 shows the longitudinal section through a spray gun with a modified
• Dispersing device as a mixing chamber and spray nozzle.
• a dispersing device has the following basic structure (FIG. 1):
• the ceramic sleeve 18 surrounds the chamber 3 of the dispersing device and has a multiplicity of bores 4, 4 ′ which open into the outlet chamber 14.
• the ceramic piston 5 is movably arranged in the chamber 3 and can be moved in the chamber 3 by means of the pneumatic drive 9, which is controlled by the pressure control 8. Depending on the position of the piston 5, the openings 4,
• the total throughput of the raw emulsion depends on the number of remaining free openings 4, 4 '.
• Fig. 2 shows a design of the dispersing device, in which the opposite straight rows of bores along the direction of movement of the piston 5 in the ceramic sleeve 18 are arranged slightly offset from one another, so that their cross sections, as in the diagram on the right (Fig. 2a) indicated, viewed from the right side, overlap each other.
• the distance A in Fig. 2 represents the length of the bore.
• FIG. 3 shows a dispersing device in which, instead of the opposite straight rows of bores along the direction of movement of the piston 5, slot nozzles 16, 16 ′ are arranged in the ceramic sleeve 18, in which the raw emulsion 12 is dispersed.
• the distance B in FIG. 3 shows the length of the slot 16.
• the distance C in FIG. 3a shows the depth of the slot 16 and the distance D in FIG. 3a shows the width of the slot 16.
• paraffin oil emulsion (model emulsion) was carried out on various dispersants using the following recipe:
• emulsifier Tween 80 / Arlacel 80 surfactant mixture, HLB 11.5 and
• FIG. 5 graphically shows the test results using a) an adjustable perforated nozzle according to FIG. 2 with 10 holes of 0.1 mm, b) a 0.1 mm wide slot nozzle with a depth of 6 mm and c) a jet disperser with fixed Dimensions and shown with 2 holes of 0.1 mm.
• the values (average particle size) for the smallest openings, a medium setting and the maximum opening are plotted from the adjustable nozzles.
• the graphic which shows the average particle size as a function of the homogenization pressure, shows a good agreement regarding the fineness of dispersion (particle size) over the entire throughput range and the good functioning of the adjustable jet dispersers compared to the disperser with a fixed opening cross section.
• Bayer AG hydroxy-functional polyacrylate dispersion, Bayer AG
• Bayhydrol VP LS 2231® 33.28% hydroxy-functional, urethane-modified polyester dispersion, Bayer AG
• Tinuvin 292® 50% in butyl diglycol acetate 0.92%
• the two components (agent component 23 and hardener 24) are mixed and emulsified in a painting installation according to FIG. 4 with adjustable dispersing nozzles 17 according to FIG. 1, each with an upstream mixer 1, 2, using 0.2 mm wide holes.
• the pumps 20, 21 produce the necessary differential pressure.
• the application takes place electrostatically via commercially available bells 22 with an upstream variable buffer volume 4 on galvanized steel sheets with a layer thickness of 40 ⁇ m.
• the paint film is flashed off at room temperature for 5 minutes, predried at 80 ° C. for 10 minutes and cured at 130 ° C. for 30 minutes.
• the paint film has the following application properties:
• Pendulum hardness according to König 23 ° C: 190s gloss 20 ° 88
• Pancreatin / sulfuric acid / caustic soda 2/1/0 scratch resistance:
• a spray gun 36 of conventional design with a dispersing nozzle with variable throughput for airless spraying is described.
• the spray gun has the following structure:
• a plurality of bores 30, 31 each lead through the nozzle body 34 for components A (bore 30) and B (bore 31).
• a plurality of slots can also be arranged in the longitudinal direction of the mixing chamber 38.
• the bores 30, 31 and 37 are connected to hose feed lines (not shown) which supply the paint components or compressed air (bore 37).
• the nozzle body 34 is made of ceramic (zirconium oxide).
• a nozzle needle 33 which is made of ceramic or hard metal (eg tungsten carbide), is moved in the chamber 38 like a piston.
• the nozzle needle 34 closes the bores 30, 31 or Slots for the passage of the dispersed material completely without the use of seals.
• the nozzle needle 34 removes all product residues from the chamber 38 when it is pierced, so that cleaning after use is only required in exceptional cases.
• the dispersed material 32 can be sprayed directly from the chamber 38 or via an additional spray nozzle 35. In order to improve the spray pattern, spray air 37 can also be supplied to the chamber.

Landscapes

• Chemical & Material Sciences (AREA)
• Dispersion Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Nozzles (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Paints Or Removers (AREA)
• Accessories For Mixers (AREA)
• Coating Apparatus (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7915052

Family Applications (1)

Country Status (9)

Families Citing this family (8)

Family Cites Families (17)

• 1999
  • 1999-07-16 DE DE19933440A patent/DE19933440A1/de not_active Withdrawn
• 2000
  • 2000-07-04 JP JP2001510593A patent/JP4781585B2/ja not_active Expired - Fee Related
  • 2000-07-04 KR KR1020027000558A patent/KR100677789B1/ko not_active IP Right Cessation
  • 2000-07-04 US US10/030,927 patent/US7007711B1/en not_active Expired - Fee Related
  • 2000-07-04 CA CA002379116A patent/CA2379116A1/en not_active Abandoned
  • 2000-07-04 EP EP00947926A patent/EP1202815A1/de not_active Ceased
  • 2000-07-04 MX MXPA02000534A patent/MXPA02000534A/es active IP Right Grant
  • 2000-07-04 AU AU61550/00A patent/AU6155000A/en not_active Abandoned
  • 2000-07-04 WO PCT/EP2000/006277 patent/WO2001005517A1/de not_active Application Discontinuation

Non-Patent Citations (1)

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